tafamidis and Amyloid-Neuropathies--Familial

This summary presents the results from an ongoing, long-term extension study that followed an earlier study called ATTR-ACT. People who took part in this extension study and ATTR-ACT have a type of heart disease known as transthyretin amyloid cardiomyopathy (ATTR-CM for short), which causes heart failure and death. In ATTR-ACT, people took either a medicine called tafamidis or a placebo (a pill that looks like the study drug but does not contain any active ingredients) for up to 2½ years. So far, in the long-term extension study, people have continued taking tafamidis, or switched from taking a placebo to tafamidis, for another 2½ years. Researchers looked at how many people died in ATTR-ACT and the extension study. The long-term extension study is expected to end in 2027, so these are interim (not final) results.. In the extension study of ATTR-ACT, the risk of dying was lower in people who took tafamidis continuously throughout ATTR-ACT and the extension study than in people who took placebo in ATTR-ACT and switched to tafamidis in the extension study.. Taking tafamidis increases how long people with ATTR-CM live. People with ATTR-CM who take tafamidis early and continuously are more likely to live longer than those who do not. These results highlight the importance of early detection and treatment in people with ATTR-CM.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Prealbumin

Tafamidis was associated with a reduction in cardiovascular hospitalizations and all-cause mortality in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) in the ATTR-ACT trial. However, real-world data on the efficacy of tafamidis are limited. We conducted a retrospective, observational cohort study using the TriNetX research network. Patients with wild-type TTR amyloidosis and heart failure (HF) were divided into 2 groups based on treatment with tafamidis. Propensity score matching (PSM) was performed, and rates of heart failure exacerbations (HFE) and all-cause mortality at 12 months were compared. After PSM, 421 patients were in each group (tafamidis vs nontafamidis). During the 12-month follow-up period, patients treated with tafamidis experienced significantly less HFE and all-cause mortality. A higher probability of event-free survival for HFE and all-cause mortality was noted with tafamidis. This real-world analysis supports that tafamidis use is associated with reduced HFE and all-cause mortality in patients with wild-type TTR amyloidosis and HF. Longer-term follow-up is needed to better understand the utility of tafamidis, given the increasing recognition of ATTR-CM and the high cost of tafamidis.

Topics: Amyloid Neuropathies, Familial; Cardiomyopathies; Heart Failure; Humans; Observational Studies as Topic; Prealbumin; Retrospective Studies

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an underdiagnosed cause of heart failure and arrhythmia. This differential diagnosis should particularly be considered in older patients with left ventricular hypertrophy (LVH) who are also suffering from heart failure with preserved ejection fraction (HFpEF) or aortic valve stenosis. ATTR-CM is caused either by a genetic variation or by aging processes. The extracellular accumulation of amyloid fibrils in the heart causes a restrictive cardiomyopathy, which leads to typical heart failure symptoms as well as cardiac conduction and repolarization disturbances. Extracardiac problems such as a carpal tunnel syndrome can also be indicative for ATTR-CM. The disease can be diagnosed either by a myocardial biopsy or alternatively by a positive bone scintigraphy with the simultaneous exclusion of monoclonal proteins in blood and urine. Besides a symptomatic treatment, the transthyretin (TTR) stabilizer tafamidis is now available, which can significantly delay the disease progress. In the coming years, the approval of further drugs for the treatment of ATTR-CM is to be expected.. Kardiale Transthyretin-Amyloidosen (ATTR-Amyloidosen) sind eine unterdiagnostizierte Ursache von Herzinsuffizienz und Arrhythmien. Insbesondere bei älteren Patienten mit einer linksventrikulären Hypertrophie (LVH), die gleichzeitig an einer Herzinsuffizienz mit erhaltener Ejektionsfraktion (HFpEF) oder Aortenklappenstenose leiden, sollte an diese Differenzialdiagnose gedacht werden. ATTR-Amyloidosen sind entweder genetisch bedingt oder entstehen durch Alterungsprozesse. Durch die extrazelluläre Akkumulation von Amyloidfibrillen im Herzen kommt es zu einer restriktiven Kardiomyopathie, die zu typischen Herzinsuffizienzsymptomen sowie Erregungsleitungs- und Erregungsrückbildungsstörungen führt. Auch extrakardiale Probleme wie ein Karpaltunnelsyndrom können auf eine kardiale ATTR-Amyloidose hindeuten. Die Erkrankung kann durch eine Myokardbiopsie oder alternativ durch eine positive Skelettszintigraphie bei gleichzeitigem Ausschluss monoklonaler Proteine im Blut und Urin diagnostiziert werden. Neben einer symptomatischen Therapie steht mittlerweile mit dem Transthyretin(TTR)-Stabilisator Tafamidis ein Medikament zur Verfügung, das den Krankheitsverlauf signifikant verlangsamen kann. In den nächsten Jahren ist mit der Zulassung weiterer Medikamente zur Behandlung der kardialen ATTR-Amyloidose zu rechnen.

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Heart Failure; Humans; Prealbumin; Stroke Volume; Tomography, X-Ray Computed

Cardiac amyloidosis is a rare and severe disease with worse prognosis than classic cardiac insufficiency. Transthyretin amyloïdosis is an underdiagnosed cause of amyloidosis. Technetium scintigraphy allows to confirm diagnosis of transthyretin amyloidosis with great specificity. A new hope is brought by tafamidis, a novel therapeutic option for this specific condition. This medication is the first one that proved a risk reduction in mortality among patients with cardiac amyloidosis in class NYHA I and II. In this article, we review across a clinical case the modalities for the diagnosis and treatment of transthyretin amyloidosis.. L’amyloïdose cardiaque est une maladie rare et sévère. En cas d’insuffisance cardiaque, le pronostic est pire que pour les autres étiologies. L’amyloïdose à transthyrétine est une des formes d’amyloïdose dont le diagnostic peut être posé avec une grande spécificité grâce à la scintigraphie au technétium. Une lueur d’espoir est apportée par l’arrivée du tafamidis, une nouvelle classe thérapeutique. Ce médicament est le premier à avoir démontré une réduction de mortalité parmi les patients en classe NYHA I et II. Dans cet article, nous décrivons, à partir d’un cas clinique, les démarches diagnostiques et thérapeutiques nécessaires à la prise en charge d’un patient présentant une insuffisance cardiaque sur amyloïdose à transthyrétine.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Therapies, Investigational

Tafamidis is the only therapy shown to improve survival in transthyretin cardiac amyloidosis (ATTR) based on randomized controlled trial data. We sought to evaluate the impact of tafamidis on survival in a real-world community-based cohort. This was a prospective observational cohort study that included consecutive patients with confirmed ATTR based on biopsy or TcPYP imaging. Baseline characteristics were compared between patients taking tafamidis vs not, and Kaplan-Meier survival analysis was performed to compare survival between these groups. We examined the reasons that ATTR patients were not on tafamidis. Of 107 ATTR patients, median age was 83.9 years, 79% were men, and 63 (59%) of them were on tafamidis. Demographics and baseline cardiovascular risk factors did not differ significantly between those on vs off tafamidis, although there was a higher proportion of NYHA Class III or IV heart failure in those off tafamidis (76% vs 57%, P < 0.01). The most common reasons patients were not on tafamidis included delays in obtaining the drug or financial barriers (59%) and NYHA Class IV heart failure (19.5%). Patients taking tafamidis had a significantly higher median survival compared to those not on tafamidis (median survival 6.70 vs 1.43 years, P < 0.0001). Our study demonstrates significantly improved survival in ATTR patients taking tafamidis. Barriers exist to tafamidis initiation including delayed access and affordability, and efforts should be made to improve patient access.

Topics: Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Female; Heart Failure; Humans; Male; Observational Studies as Topic; Prospective Studies

Transthyretin (ATTR) amyloidosis is a multisystem disease caused by organ deposition of amyloid fibrils derived from the misfolded transthyretin (TTR) protein. The purpose of this article is to provide an overview of current treatment regimens and summarize important considerations for each agent. A literature search was performed with the PubMed database for articles published through October 2020. Search criteria included therapies available on the market and investigational therapies used for ATTR amyloidosis treatment. Both prospective clinical trials and retrospective studies have been included in this review. Available therapies discussed in this review article are tafamidis, diflunisal, patisiran, and inotersen. Tafamidis is FDA approved for treatment of wild-type ATTR (ATTRwt) and hereditary ATTR (ATTRv) cardiomyopathy, and patisiran and inotersen are FDA approved for ATTRv polyneuropathy. Diflunisal does not have an FDA-labeled indication for amyloidosis but has been studied in ATTRv polyneuropathy and ATTRwt cardiomyopathy. Investigational therapies include a TTR stabilizer, AG10; 2 antifibril agents, PRX004 and doxycycline/tauroursodeoxycholic acid; and 2 gene silencers, vutrisiran and AKCEA-TTR-LRx; and clinical trials are ongoing. ATTR amyloidosis treatment selection is based on subtype and presence of cardiac or neurological manifestations. Additional considerations such as side effects, monitoring, and administration are outlined in this review.

Topics: Amyloid Neuropathies, Familial; Animals; Benzoxazoles; Cardiomyopathies; Cardiovascular Agents; Diflunisal; Genetic Predisposition to Disease; Humans; Mutation; Oligonucleotides; Phenotype; Prealbumin; RNA, Small Interfering; Treatment Outcome

Cardiac amyloidosis is an underrecognized cause of heart failure. We review clinical clues to the diagnoses, a rational approach to testing, and current and emerging therapies.. Advances in the diagnosis of amyloid cardiomyopathy include (1) use of

Topics: Amyloid Neuropathies, Familial; Amyloidosis; Benzoxazoles; Cardiomyopathies; Heart Failure; Humans; Immunoglobulin Light-chain Amyloidosis

Often considered a rare disease, cardiac amyloidosis is increasingly recognized by practicing clinicians. The increased rate of diagnosis is in part due the aging of the population and increasing incidence and prevalence of cardiac amyloidosis with advancing age, as well as the advent of noninvasive methods using nuclear scintigraphy to diagnose transthyretin cardiac amyloidosis due to either variant or wild type transthyretin without a biopsy. Perhaps the most important driver of the increased awareness is the elucidation of the biologic mechanisms underlying the pathogenesis of cardiac amyloidosis which have led to the development of several effective therapies with differing mechanisms of actions. In this review, the mechanisms underlying the pathogenesis of cardiac amyloidosis due to light chain (AL) or transthyretin (ATTR) amyloidosis are delineated as well as the rapidly evolving therapeutic landscape that has emerged from a better pathophysiologic understanding of disease development.

Topics: Aging; Alkylating Agents; Amyloid; Amyloid Neuropathies, Familial; Amyloidosis; Antibodies, Monoclonal; Benzoates; Benzoxazoles; Bridged Bicyclo Compounds, Heterocyclic; Cardiomyopathies; Catechol O-Methyltransferase Inhibitors; Heart Transplantation; Humans; Immunomodulating Agents; Oligonucleotides; Proteasome Inhibitors; Protein Folding; Pyrazoles; RNA, Small Interfering; Stem Cell Transplantation; Sulfonamides; Tolcapone

Amyloidosis is a group of diseases that includes Alzheimer's disease, prion diseases, transthyretin (ATTR) amyloidosis, and immunoglobulin light chain (AL) amyloidosis. The mechanism of organ dysfunction resulting from amyloidosis has been a topic of debate. This review focuses on the ultrastructure of tissue damage resulting from amyloid deposition and therapeutic insights based on the pathophysiology of amyloidosis. Studies of nerve biopsy or cardiac autopsy specimens from patients with ATTR and AL amyloidoses show atrophy of cells near amyloid fibril aggregates. In addition to the stress or toxicity attributable to amyloid fibrils themselves, the toxicity of non-fibrillar states of amyloidogenic proteins, particularly oligomers, may also participate in the mechanisms of tissue damage. The obscuration of the basement and cytoplasmic membranes of cells near amyloid fibrils attributable to an affinity of components constituting these membranes to those of amyloid fibrils may also play an important role in tissue damage. Possible major therapeutic strategies based on pathophysiology of amyloidosis consist of the following: (1) reducing or preventing the production of causative proteins; (2) preventing the causative proteins from participating in the process of amyloid fibril formation; and/or (3) eliminating already-deposited amyloid fibrils. As the development of novel disease-modifying therapies such as short interfering RNA, antisense oligonucleotide, and monoclonal antibodies is remarkable, early diagnosis and appropriate selection of treatment is becoming more and more important for patients with amyloidosis.

Topics: Alzheimer Disease; Amyloid; Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Humans; Immunoglobulin Light Chains; Immunoglobulin Light-chain Amyloidosis; Immunologic Factors; Myocardium; Neuroprotective Agents; Oligonucleotides; Peripheral Nerves; Prealbumin; Prion Diseases; RNA, Small Interfering

Cardiac amyloidosis (CA) is an infiltrative and restrictive cardiomyopathy that leads to heart failure, reduced quality of life, and death. The disease has two main subtypes, transthyretin cardiac amyloidosis (ATTR-CA) and immunoglobulin light chain cardiac amyloidosis (AL-CA), characterized by the nature of the infiltrating protein. ATTR-CA is further subdivided into wild-type (ATTRwt-CA) and variant (ATTRv-CA) based on the presence or absence of a mutation in the transthyretin gene. CA is significantly underdiagnosed and increasingly recognized as a cause of heart failure with preserved ejection fraction. Advances in diagnosis that employ nuclear scintigraphy to diagnose ATTR-CA without a biopsy and the emergence of effective treatments, including transthyretin stabilizers and silencers, have changed the landscape of this field and render early and accurate diagnosis critical. This review summarizes the epidemiology, pathophysiology, diagnosis, prognosis, and management of CA with an emphasis on the significance of recent developments and suggested future directions.

Topics: Amyloid Neuropathies, Familial; Amyloidosis; Arrhythmias, Cardiac; Benzoates; Benzoxazoles; Biopsy; Cardiac Pacing, Artificial; Cardiomyopathies; Diflunisal; Disease Progression; Early Diagnosis; Early Medical Intervention; Echocardiography; Electrocardiography; Heart Failure; Humans; Immunoglobulin Light-chain Amyloidosis; Immunologic Factors; Magnetic Resonance Imaging; Oligonucleotides; Prealbumin; Prognosis; Proteasome Inhibitors; Pyrazoles; Radionuclide Imaging; RNA, Small Interfering

Topics: Adult; Amyloid Neuropathies, Familial; Bayes Theorem; Benzoxazoles; Female; Humans; Male; Middle Aged; Network Meta-Analysis; Oligonucleotides; Polyneuropathies; RNA, Small Interfering

Disease-modifying pharmacological agents for transthyretin (TTR)-related familial amyloid polyneuropathy (FAP) have become available in the last decade, but evidence on their efficacy and safety is limited. This review focuses on disease-modifying pharmacological treatment for TTR-related and other FAPs, encompassing amyloid kinetic stabilisers, amyloid matrix solvents, and amyloid precursor inhibitors.. To assess and compare the efficacy, acceptability, and tolerability of disease-modifying pharmacological agents for familial amyloid polyneuropathies (FAPs).. On 18 November 2019, we searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase. We reviewed reference lists of articles and textbooks on peripheral neuropathies. We also contacted experts in the field. We searched clinical trials registries and manufacturers' websites.. We included randomised clinical trials (RCTs) or quasi-RCTs investigating any disease-modifying pharmacological agent in adults with FAPs. Disability due to FAP progression was the primary outcome. Secondary outcomes were severity of peripheral neuropathy, change in modified body mass index (mBMI), quality of life, severity of depression, mortality, and adverse events during the trial.. We followed standard Cochrane methodology.. The review included four RCTs involving 655 people with TTR-FAP. The manufacturers of the drugs under investigation funded three of the studies. The trials investigated different drugs versus placebo and we did not conduct a meta-analysis. One RCT compared tafamidis with placebo in early-stage TTR-FAP (128 randomised participants). The trial did not explore our predetermined disability outcome measures. After 18 months, tafamidis might reduce progression of peripheral neuropathy slightly more than placebo (Neuropathy Impairment Score (NIS) in the lower limbs; mean difference (MD) -3.21 points, 95% confidential interval (CI) -5.63 to -0.79; P = 0.009; low-certainty evidence). However, tafamidis might lead to little or no difference in the change of quality of life between groups (Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) total score; MD -4.50 points, 95% CI -11.27 to 2.27; P = 0.19; very low-certainty evidence). No clear between-group difference was found in the numbers of participants who died (risk ratio (RR) 0.65, 95% CI 0.11 to 3.74; P = 0.63; very low-certainty evidence), who dropped out due to adverse events (RR 1.29, 95% CI 0.30 to 5.54; P = 0.73; very low-certainty evidence), or who experienced at least one severe adverse event during the trial (RR 1.16, 95% CI 0.37 to 3.62; P = 0.79; very low-certainty evidence). One RCT compared diflunisal with placebo (130 randomised participants). At month 24, diflunisal might reduce progression of disability (Kumamoto Score; MD -4.90 points, 95% CI -7.89 to -1.91; P = 0.002; low-certainty evidence) and peripheral neuropathy (NIS plus 7 nerve tests; MD -18.10 points, 95% CI -26.03 to -10.17; P < 0.001; low-certainty evidence) more than placebo. After 24 months, changes from baseline in the quality of life measured by the 36-Item Short-Form Health Survey score showed no clear difference between groups for the physical component (MD 6.10 points, 95% CI 2.56 to 9.64; P = 0.001; very low-certainty evidence) and the mental component (MD 4.40 points, 95% CI -0.19 to 8.99; P = 0.063; very low-certainty evidence). There was no clear between-group difference in the number of people who died (RR 0.46, 95% CI 0.15 to 1.41; P = 0.17; very low-certainty evidence), in the number of dropouts due to adverse events (RR 2.06, 95% CI 0.39 to 10.87; P = 0.39; very low-certainty evidence), and in the number of people who experienced at least one severe adverse event (RR 0.77, 95% CI 0.18 to 3.32; P = 0.73; very l. Evidence on the pharmacological treatment of FAPs from RCTs is limited to TTR-FAP. No studies directly compare disease-modifying pharmacological treatments for TTR-FAP. Results from placebo-controlled trials indicate that tafamidis, diflunisal, patisiran, and inotersen may be beneficial in TTR-FAP, but further investigations are needed. Since direct comparative studies for TTR-FAP will be hampered by sample size and costs required to demonstrate superiority of one drug over another, long-term non-randomised open-label studies monitoring their efficacy and safety are needed.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Disease Progression; Humans; Oligonucleotides; Patient Dropouts; Quality of Life; Randomized Controlled Trials as Topic; RNA, Small Interfering

To carry out a systematic review of the literature to analyse the efficacy and safety of treatments available or under investigation for amyloidosis due to mutations in the transthyretin gene (ATTR).. A bibliographic search was carried out in the following electronic databases up to September 2017: PubMed, Cochrane Library and EMBASE. The inclusion criteria were: efficacy and/or safety studies conducted in humans, studies that included treatments, including treatments in the research phase, and studies that included 10 or more patients.. A total of 21 articles were included; 16 were clinical trials, eight of them (50%) phase III trials, and five were observational studies. Of the total number of studies selected, 11 were on tafamidis, four on diflunisal, two on liver transplantation, two on patisiran and two on other therapeutic alternatives. Of the 11 studies related to the drug, the pivotal trial, the results of its two extension studies and an additional post hoc analysis were selected. In addition, two phase III trials were included in specific populations, two phase II studies, one safety study and two observational studies. Regarding the four included studies related to the drug, one was the pivotal trial that gave the indication to diflunisal, another a safety summary of the pivotal trial, and the other two trials were carried out in specific populations, one in a Japanese population and another phase I trial in cardiac amyloidosis in the USA. As far as other alternatives are concerned, of the six studies included in this section, two were related to liver transplantation, two to patisiran and two to different therapeutic alternatives.. Sufficient evidence has not been found that demonstrates superiority among the available oral alternatives, diflunisal or tafamidis, in the treatment of ATTR. Direct comparisons between both drugs and pharmacoeconomic studies would be necessary to select the most efficient treatment.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Humans; Liver Transplantation; RNA, Small Interfering

Hereditary transthyretin amyloidosis (ATTRv) is a rare autosomal dominant, life-threatening disease. Until recently only early stages of ATTRv-PN (polyneuropathy) had access to disease-modifying therapy (DMT), whereas there was no specific treatment for ATTRv-CM (cardiomyopathy). This review updates our knowledge about results of three phase 3 clinical trials, expert's consensus for early diagnosis and emerging biomarkers.. Two phase 3 studies using RNAi and antisense oligonucleotides (ASO) were successful. Primary endpoints were progression of neuropathic score mNIS +7 and quality of Life (QOL) in a population of ATTRv-PN at different levels of severity. They knock downed circulating amyloidogenic mutant and wild-type TTR. Safety concerned ASO with a risk of thrombocytopenia. RNAi showed possible reversibility of the disease. Phase 3 ATTRACT trial-tested tafamidis versus placebo in patients with ATTRv-CM and ATTRwt-CM and showed a significant reduction of all-cause mortality and rates of cardiovascular-related hospitalizations. All three drugs obtained marketing authorization by European Medicines Agency (EMA) and Food and drug administration (FDA). Early diagnosis criteria for ATTRv-PN and ATTRv-CM are available. Ongoing clinical trials for ATTRv are presented. New biomarkers are plasma neurofilament light chain, intraepidermal nerve fiber density.. The majority of patients with ATTRv may have now access to a DMT. Criteria for early diagnosis are available.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Biomarkers; Clinical Trials as Topic; Disease Progression; Humans; Oligonucleotides, Antisense; Quality of Life

Transthyretin (TTR) cardiac amyloidosis results from the dissociation of the tetrameric, liver-synthetized transport protein, either because of a mutation (hereditary CA), or spontaneously due to ageing (wild type CA). Monomers self-associate into amyloid fibrils within the myocardium, causing heart failure, arrhythmias and conduction defects. This overlooked disease must be recognized in case of unexplained increased thickness of the myocardium, particularly in subjects of African descent, in patients with heart failure and preserved ejection fraction, and in those with aortic stenosis. Some extra-cardiac symptoms must also be considered as red flags: carpal tunnel syndrome, lumbar canal stenosis, recent deafness, peripheral neuropathy, or dysautonomia. Medical assessment includes an electrocardiogram, biological assessment including troponin, natriuretic peptide and monoclonal protein assay, echocardiography with 2-D strain study, MRI and bone scintigraphy. Once the diagnosis established, cardiologic management must avoid beta-blockers and other rate-slowing drugs, which are deleterious in restrictive cardiomyopathy, and restrain the use of renin-angiotensin system inhibitors, of little use and often poorly tolerated. Congestion must be treated with diuretics. Anticoagulants are often necessary due to the risk of arrhythmias and stroke. Pacemaker or defibrillator implantation should be determined in patients with high risk of sudden death. Until now, etiologic treatments were liver and/or heart transplantation in some rare cases. Tafamidis, a TTR stabilizer has recently been approved, and new therapeutic approaches targeting TTR at the transcriptional level are under investigation.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Echocardiography; Electrocardiography; Humans

Background The emergence of specific therapies for transthyretin cardiac amyloidosis (CA) warrants the need for a systematic review of the literature. Methods and Results A systematic review of the literature was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search was performed on MEDLINE, PubMed, and Embase databases on November 29, 2019. Studies were selected based on the following predefined eligibility criteria: English-language randomized controlled trials (RCTs), non-RCTs, or observational studies, which included adult patients with variant/wild-type transthyretin-CA, assessed specific therapies for transthyretin-CA, and reported cardiovascular outcomes. Relevant data were extracted to a predefined template. Quality assessment was based on National Institute for Health and Care Excellence recommendations (RCTs) or a checklist by Downs and Black (non-RCTs). From 1203 records, 24 publications were selected, describing 4 RCTs (6 publications) and 16 non-RCTs (18 publications). Tafamidis was shown to significantly improve all-cause mortality and cardiovascular hospitalizations and reduce worsening in 6-minute walk test, Kansas City Cardiomyopathy Questionnaire-Overall Summary score, and NT-proBNP (N-terminal pro-B-type natriuretic peptide) in variant/wild-type transthyretin-CA. Patisiran showed promising results in a subgroup analysis of patients with variant transthyretin-CA, which have to be confirmed in RCTs. Inotersen showed conflicting results on cardiac imaging parameters. The one study on AG10 had only a 1-month duration and cardiovascular end points were exploratory and limited to cardiac biomarkers. Limited evidence from noncomparative single-arm small non-RCTs existed for diflunisal, epigallocatechin-3-gallate (green tea extract), and doxycycline+tauroursodeoxycholic acid/ursodeoxycholic acid. Conclusions This systematic review of the literature supports the use of tafamidis in wild-type and variant transthyretin-CA. Novel therapeutic targets including transthyretin gene silencers are currently under investigation.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Cardiovascular Agents; Genetic Therapy; Humans

Autonomic dysfunction is a very common, early and distressing aspect of hereditary transthyretin (ATTR) amyloidosis leading to significant loss of quality of life and morbidity for patients. Although the clinical variability of ATTR has been well characterized as neuropathic, cardiac or mixed phenotype, the extent of autonomic involvement remains poorly understood. Despite the fact that the autonomic nervous system has not been specifically evaluated in any of the clinical trials of tafamidis, and that, for some primary and secondary endpoints used in these trials, the behavior cannot be separated from non-autonomic items, an attempt was made to use published material to indirectly access the efficacy of tafamidis in treating dysautonomia.. Literature review summarizing the results of primary and secondary endpoints related to the autonomic features used in the original tafamidis trials, the post hoc publications, and real-world data, on the effect of tafamidis on autonomic dysfunction in patients with ATTR amyloidosis.. There is some evidence that indirectly demonstrates that tafamidis is safe and could slow or arrest the progression of autonomic neuropathy in patients with ATTR amyloidosis, in addition to its well-described effects to ameliorate sensory-motor peripheral neuropathy.. Although the current evidence is scarce, tafamidis might be effective in arresting the progression of autonomic neuropathy in patients with ATTR amyloidosis. Tafamidis might be more effective at the early stage of the disease; however, individual responses must be monitored.

Topics: Amyloid Neuropathies, Familial; Autonomic Nervous System Diseases; Benzoxazoles; Humans; Polyneuropathies

Hereditary transthyretin-mediated amyloidosis (hATTR amyloidosis) is a progressive, life-threatening disease. Until recently, tafamidis was the only approved pharmacotherapy. Patisiran significantly improved polyneuropathy and quality of life (QoL) in the phase III APOLLO trial. In the absence of direct comparisons, this analysis aimed to evaluate the comparative efficacy of tafamidis and patisiran in hATTR amyloidosis with polyneuropathy.. Randomized controlled trial evidence for tafamidis was identified by systematic literature review. Indirect treatment comparisons were performed using the standard pairwise Bucher method for endpoints used in both APOLLO and the tafamidis Fx-005 trial: change from baseline in Neuropathy Impairment Score-lower limbs (NIS-LL), Norfolk QoL-Diabetic Neuropathy questionnaire (QoL-DN), NIS-LL response, and mBMI vs. placebo. Inter-trial population differences were assessed by sensitivity analysis.. The base-case analysis (FAP Stage 1 APOLLO patients vs. intent-to-treat Fx-005 population) suggested patisiran had a greater treatment effect vs. tafamidis for all endpoints, with significant improvements in mean change in NIS-LL (-5.49) and QoL-DN (-13.10) from baseline to Month 18. Similar trends were observed in all sensitivity analyses.. In the absence of direct comparisons, this analysis suggests patisiran has a greater treatment effect than tafamidis in patients with hATTR amyloidosis with polyneuropathy.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Polyneuropathies; Quality of Life; Randomized Controlled Trials as Topic; RNA, Small Interfering; Surveys and Questionnaires

Transthyretin (TTR) related cardiomyopathy is an underdiagnosed cause of heart failure but is increasingly recognized in various settings - from patients admitted with heart failure to symptomatic aortic stenosis - and is rapidly becoming the most frequent form of systemic amyloidosis. Following the recent publication of the landmark ATTR-ACT trial that showed tafamidis to be the first treatment to improve survival in patients with TTR-related cardiac amyloidosis and heart failure, we reviewed the drug's rationale, characteristics and evidence supporting its use in TTR amyloidosis.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Global Health; Heart Failure; Humans; Survival Rate

Amyloidosis is caused by extracellular deposition of insoluble abnormal fibrils constituted by misfolded proteins, which can modify tissue anatomy and hinder the function of multiple organs including the heart. Amyloidosis that can affect the heart includes mostly systemic amyloidosis (amyloid light chain, AL) and transthyretin amyloidosis (ATTR). The latter can be acquired in elderly patients (ATTRwt), or be inherited in younger individuals (ATTRm). The diagnosis is demanding given the high phenotypic heterogeneity of the disease. Therefore, "red flags," which are suggestive features giving support to diagnostic suspicion, are extremely valuable. However, the lack of broad awareness among clinicians represents a major obstacle for early diagnosis and treatment of ATTR. Furthermore, recent implementation of noninvasive diagnostic techniques has revisited the need for endomyocardial biopsy (EMB). In fact, unlike AL amyloidosis, which requires tissue confirmation and typing for diagnosis, ATTR can now be diagnosed noninvasively with the combination of bone scintigraphy and the absence of a monoclonal protein. Securing the correct diagnosis is pivotal for the newly available therapeutic options targeting both ATTRm and ATTRwt, and are directed to either stabilization of the abnormal protein or the reduction of the production of transthyretin. The purpose of this article is to review the contemporary aspects of diagnosis and management of transthyretin amyloidosis with cardiac involvement, summarizing also the recent therapeutic advances with tafamidis, patisiran, and inotersen.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Biomarkers; Cardiomyopathies; Diagnosis, Differential; Echocardiography; Electrocardiography; Humans; Magnetic Resonance Imaging; Oligonucleotides; Radionuclide Imaging; RNA, Small Interfering

There have now been randomized controlled trials of four different therapeutics for hereditary amyloid polyneuropathy related to transthyretin (TTR) deposition and one for amyloidotic cardiomyopathy of both genetic and sporadic origin. It is likely that in the next few months those not already approved by either the US Food and Drug Administration (FDA) and/or the European Medicines Authority (EMA) will receive similar approvals for treatment for all or particular groups of patients. This is a far cry from circumstances less than 10 years ago when the only available therapy was gene replacement by liver transplant. The randomized controlled trials have shown that all the treatments (tafamidis, diflunisal, patisiran, and inotersen) are effective in the context of a clinical trial. However, we have very little idea of whether individual patients will respond in an equally positive way to all the drugs or whether there will be some who respond better to one or another or not respond at all, nor do we know whether combinations will be additive or synergistic. We lack validated markers of clinical response. While the small molecule TTR stabilizers increase serum TTR levels, the RNA-based drugs lower serum TTR. In the latter case, it is not clear that the reduction in serum TTR is related to the clinical response in a 1:1 fashion. Pharmaceutical companies have made substantial investments in the development of these agents and will clearly attempt to recoup those investments quickly. It is incumbent upon those of us who care for these patients to develop ways to assess the effects of therapy in the shortest possible time at the lowest possible cost. The better we are able to accomplish this the more likely it is that we will be able to treat the most patients in the most clinically efficient fashion regardless of their economic status. We now have the drugs we just have to figure out who should get them and when.

Topics: Amyloid Neuropathies; Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Female; Humans; Male; Oligonucleotides; Prealbumin; Precision Medicine; Randomized Controlled Trials as Topic; RNA, Small Interfering; Treatment Outcome

Transthyretin amyloidosis with polyneuropathy (ATTR-PN), a rare and progressive hereditary disorder, results from mutations in the gene coding for the transthyretin (TTR) protein that destabilize the protein's tetrameric structure. In over 40 countries worldwide, tafamidis (Vyndaqel

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Clinical Trials as Topic; Disease Progression; Drug Approval; Humans; Mutation; Polyneuropathies; Prealbumin; Quality of Life

Transthyretin (TTR) is a tetrameric protein synthesized mostly by the liver. As a result of gene mutations or as an ageing-related phenomenon, TTR molecules may misfold and deposit in the heart and in other organs as amyloid fibrils. Cardiac involvement in TTR-related amyloidosis (ATTR) manifests typically as left ventricular pseudohypertrophy and/or heart failure with preserved ejection fraction. ATTR is an underdiagnosed disorder as well as a crucial determinant of morbidity and mortality, thus justifying the current quest for a safe and effective treatment. Therapies targeting cardiac damage and its direct consequences may yield limited benefit, mostly related to dyspnoea relief through diuretics. For many years, liver or combined heart and liver transplantation have been the only available treatments for patients with mutations causing ATTR, including those with cardiac involvement. The therapeutic options now include several pharmacological agents that inhibit hepatic synthesis of TTR, stabilize the tetramer, or disrupt fibrils. Following the positive results of a phase 3 trial on tafamidis, and preliminary findings on patisiran and inotersen in patients with ATTR-related neuropathy and cardiac involvement, we provide an update on this rapidly evolving field, together with practical recommendations on the management of cardiac involvement.

Topics: Amyloid; Amyloid Neuropathies; Amyloid Neuropathies, Familial; Benzoxazoles; Clinical Trials, Phase III as Topic; Combined Modality Therapy; Heart Failure; Heart Transplantation; Humans; Liver Transplantation; Mutation; Oligonucleotides; Prealbumin; RNA, Small Interfering; Stroke Volume

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a life-threatening, progressive, infiltrative disease caused by the deposition of transthyretin amyloid fibrils in the heart, and can often be overlooked as a common cause of heart failure. Delayed diagnosis due to lack of disease awareness and misdiagnosis results in a poorer prognosis. Early accurate diagnosis is therefore key to improving patient outcomes, particularly in the context of both the recent approval of tafamidis in some countries (including the United States) for the treatment of ATTR-CM, and of other promising therapies under development. With the availability of scintigraphy as an inexpensive, noninvasive diagnostic tool, the rationale to screen for ATTR-CM in high-risk populations of patients is increasingly warranted. Here the authors propose a framework of clinical scenarios in which screening for ATTR-CM is recommended, as well as diagnostic "red flags" that can assist in its diagnosis among the wider population of patients with heart failure.

Topics: Age Factors; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Delayed Diagnosis; Diagnostic Errors; Early Diagnosis; Early Medical Intervention; Heart Failure; Humans; Stroke Volume

Hereditary ATTR (ATTRm) amyloidosis (also called transthyretin-type familial amyloid polyneuropathy [ATTR-FAP]) is an autosomal-dominant, adult-onset, rare systemic disorder predominantly characterized by irreversible, progressive, and persistent peripheral nerve damage. TTR gene mutations (e.g. replacement of valine with methionine at position 30 [Val30Met (p.Val50Met)]) lead to destabilization and dissociation of TTR tetramers into variant TTR monomers, which form amyloid fibrils that deposit in peripheral nerves and various organs, giving rise to peripheral and autonomic neuropathy and several non-disease specific symptoms.Phenotypic and genetic variability and non-disease-specific symptoms often delay diagnosis and lead to misdiagnosis. Red-flag symptom clusters simplify diagnosis globally. However, in Japan, types of TTR variants, age of onset, penetrance, and clinical symptoms of Val30Met are more varied than in other countries. Hence, development of a Japan-specific red-flag symptom cluster is warranted. Presence of progressive peripheral sensory-motor polyneuropathy and ≥1 red-flag sign/symptom (e.g. family history, autonomic dysfunction, cardiac involvement, carpal tunnel syndrome, gastrointestinal disturbances, unexplained weight loss, and immunotherapy resistance) suggests ATTR-FAP. Outside of Japan, pharmacotherapeutic options are first-line therapy. However, because of positive outcomes (better life expectancy and higher survival rates) with living donor transplant in Japan, liver transplantation remains first-line treatment, necessitating a Japan-specific treatment algorithm.Herein, we present a consolidated review of the ATTR-FAP Val30Met landscape in Japan and summarize findings from a medical advisory board meeting held in Tokyo on 18th August 2016, at which a Japan-specific ATTR-FAP red-flag symptom cluster and treatment algorithm was developed. Beside liver transplantation, a TTR-stabilizing agent (e.g. tafamidis) is a treatment option. Early diagnosis and timely treatment using the Japan-specific red-flag symptom cluster and treatment algorithm might help guide clinicians regarding apt and judicious use of available treatment modalities.

Topics: Algorithms; Amyloid Neuropathies, Familial; Benzoxazoles; Carpal Tunnel Syndrome; Humans; Japan; Liver Transplantation; Methionine; Mutation; Valine

Transthyretin amyloidosis is a rare, life-threatening disease resulting from aggregation and deposition of transthyretin amyloid fibrils in various tissues. There are 2 predominate phenotypic presentations of the disease: transthyretin familial amyloid polyneuropathy, which primarily affects the peripheral nerves, and transthyretin cardiomyopathy (TTR-CM), which primarily affects the heart. However, there is a wide overlap with symptoms at presentation and disease course being highly variable and influenced by the underlying transthyretin mutation, age of the affected individual, sex, and geographic location. Treatment of transthyretin amyloidosis is typically focused on symptom management. Although tafamidis has been shown to delay neurologic progression of transthyretin familial amyloid polyneuropathy, there are no approved pharmacologic therapies shown to improve survival in TTR-CM. The natural history of TTR-CM is poorly characterized, which presents difficulties for the design of large-scale trials for new treatments. This review provides a brief overview of TTR-CM and the challenges of identifying clinically meaningful end points and study parameters to determine the efficacy of treatments for rare diseases. The design and rationale behind the ongoing phase 3 ATTR-ACT study (Tafamidis in Transthyretin Cardiomyopathy Clinical Trial), an international, multicenter, double-blind, placebo-controlled, randomized clinical trial, is also outlined. The ATTR-ACT study will provide important insight into the efficacy and safety of tafamidis for the treatment of TTR-CM.. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994889.

Topics: Administration, Oral; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Clinical Trials, Phase III as Topic; Disease Management; Disease Progression; Humans; Randomized Controlled Trials as Topic

Transthyretin Familial Amyloid Polyneuropathy (TTR-FAP) is a rare disease with autosomal dominant transmission due to a point mutation of the TTR gene. By removing the main source of systemic mutant TTR, liver transplantation (LT) has become the reference therapy of this severe and fatal polyneuropathy of adult-onset, stopping disease progression in subgroup of patients. Recently, new therapeutic strategies have emerged, which intend to stabilize TTR or to silence the TTR gene. Amongst them, the TTR kinetic stabilizer tafamidis is the first drug approved in the EU.. We shall review the natural history of TTR-FAP and the best indications for LT. Data on the efficacy, safety and tolerability of the TTR kinetic stabilizers, tafamidis and diflunisal, have been reviewed, from the pivotal Phase III clinical trials published in PubMed medical journals or presented at international meetings. We will review the ongoing phase III clinical trials of TTR gene silencing with RNAi therapeutics and ASO published in clinicaltrialgov.. Due to the data on efficacy, tolerability, safety, tafamidis and diflunisal became the first line anti-amyloid treatment in stage 1 TTR-FAP. Both drugs slow progression of the disease. Only tafamidis got marketing authorization. We are waiting for results of the 2 phase III clinical trials of TTR gene silencing in varied stages of the disease.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Clinical Trials, Phase III as Topic; Diflunisal; Disease Progression; Gene Silencing; Humans; Liver Transplantation; Prealbumin; Receptors, Albumin

Transthyretin-cardiac amyloidoses (ATTR-CA) are an underdiagnosed but increasingly recognized cause of heart failure. Extracellular deposition of fibrillary proteins into tissues due to a variety of inherited transthyretin mutations in ATTRm or due to advanced age in ATTRwt eventually leads to organ failure. In the heart, amyloid deposition causes diastolic dysfunction, restrictive cardiomyopathy with progressive loss of systolic function, arrhythmias, and heart failure. While traditional treatments have consisted of conventional heart failure management and supportive care for systemic symptoms, numerous disease-modifying therapies have emerged over the past decade. From organ transplantation to transthyretin stabilizers (diflunisal, tafamidis, AG-1), TTR silencers (ALN-ATTR02, ISIS-TTR(Rx)), and degraders of amyloid fibrils (doxycycline/TUDCA), the potential for effective transthyretin amyloid therapy is greater now than ever before. In light of these multiple agents under investigation in human clinical trials, clinicians should be familiar with the systemic cardiac amyloidoses, their differing pathophysiology, natural histories, and unique treatment strategies.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Biomarkers; Cardiomyopathies; Cyclooxygenase Inhibitors; Defibrillators, Implantable; Diflunisal; Doxycycline; Heart Failure; Humans; Oligonucleotides, Antisense; Organ Transplantation; Pacemaker, Artificial; RNA, Small Interfering

Transthyretin (ATTR) amyloidosis is a life-threatening, gain-of-toxic-function disease characterised by extracellular deposition of amyloid fibrils composed of transthyretin (TTR). TTR protein destabilised by TTR gene mutation is prone to dissociate from its native tetramer to monomer, and to then misfold and aggregate into amyloid fibrils, resulting in autosomal dominant hereditary amyloidosis, including familial amyloid polyneuropathy, familial amyloid cardiomyopathy and familial leptomeningeal amyloidosis. Analogous misfolding of wild-type TTR results in senile systemic amyloidosis, now termed wild-type ATTR amyloidosis, characterised by acquired amyloid disease in the elderly. With the availability of genetic, biochemical and immunohistochemical diagnostic tests, patients with ATTR amyloidosis have been found in many nations; however, misdiagnosis is still common and considerable time is required before correct diagnosis in many cases. The current standard first-line treatment for hereditary ATTR amyloidosis is liver transplantation, which allows suppression of the main source of variant TTR. However, large numbers of patients are not suitable transplant candidates. Recently, the clinical effects of TTR tetramer stabilisers, diflunisal and tafamidis, were demonstrated in randomised clinical trials, and tafamidis has been approved for treatment of hereditary ATTR amyloidosis in European countries and in Japan. Moreover, antisense oligonucleotides and small interfering RNAs for suppression of variant and wild-type TTR synthesis are promising therapeutic approaches to ameliorate ATTR amyloidosis and are currently in phase III clinical trials. These newly developed therapies are expected to be effective for not only hereditary ATTR amyloidosis but also wild-type ATTR amyloidosis.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Humans; Mutation; Prealbumin

There are two forms of transthyretin (TTR) amyloidosis: non-hereditary and hereditary. The non-hereditary form (ATTRwt) is caused by native or wild-type TTR and was previously referred to as senile systemic amyloidosis. The hereditary form (ATTRm) is caused by variant TTR which results from a genetic mutation of TTR. The predominant effect of ATTRwt amyloidosis is on the heart, with patients having a greater left ventricular wall thickness at presentation than the devastating form which is light chain (AL) amyloidosis. ATTRm amyloidosis is broadly split into two categories: a type that predominantly affects the nervous system (often called familial amyloid polyneuropathy (FAP)) and one with a predilection for the heart (often called familial amyloid cardiomyopathy (FAC)). Approximately half of all TTR mutations known to express a clinical phenotype cause a cardiomyopathy. Since the introduction of orthotopic liver transplantation for ATTRm amyloidosis in 1991, several additional therapies have been developed. These therapies aim to provide a reduction or elimination of TTR from the plasma (through genetic approaches), stabilisation of the TTR molecule (to prevent deposition) and dissolution of the amyloid matrix. We describe the latest developments in these approaches to management, many of which are also applicable to wild-type amyloidosis.

Topics: Amyloid Neuropathies, Familial; Anti-Inflammatory Agents, Non-Steroidal; Benzoxazoles; Doxycycline; Echocardiography; Humans; Liver Transplantation; Molecular Targeted Therapy; Prealbumin; Prognosis; RNA, Small Interfering; Taurochenodeoxycholic Acid

Transthyretin familial amyloid polyneuropathy (TTR-FAP) classically presents as a length dependent small fiber polyneuropathy in endemic countries like Portugal. In nonendemic countries, it may mimic a variety of chronic polyneuropathies, with several phenotypes: ataxic, upper limb onset neuropathy, or motor. In these cases, there is usually a late onset and no positive family history. TTR gene sequencing appears the most pertinent first-line test for diagnosis. Cardiac involvement of various severities is common in FAP. Liver transplantation remains the standard antiamyloid therapy with better results in Val30Met TTR-FAP of early onset. Antiamyloid medication has been developed. (1) TTR stabilizers: Tafamidis was the first drug approved in Europe in stage 1 (walking unaided) TTR-FAP to slow progression of the disease; diflunisal has been assessed in a phase 3 clinical trial; (2) TTR gene silencing is a new strategy to inhibit production of both mutant and nonmutant TTR with antisense oligonucleotides or SiRNA (2 ongoing phase 3 clinical trials).

Topics: Amyloid Neuropathies, Familial; Animals; Benzoxazoles; Gene Silencing; Humans; Liver Transplantation; Mutation; Prealbumin

Transthyretin (TTR) is a representative amyloidogenic protein in humans. Rate-limiting tetramer dissociation and rapid monomer misfolding and misassembly of variant TTR result in autosomal dominant familial amyloidosis. Analogous misfolding of wild-type TTR results in senile systemic amyloidosis (SSA) presenting as sporadic amyloid disease in the elderly. The objective of this review is to summarize recent progress in our understanding and treatment of TTR amyloidosis.. Literature searches were conducted on the topics of transthyretin, familial amyloid polyneuropathy and clinical trials, using PubMed, the United States clinical trials directory, pharmaceutical company websites and news reports. The information was collected, evaluated for relevance and quality, critically assessed and summarized.. The current standard first-line treatment of familial TTR amyloidosis is liver transplantation. However, large numbers of patients are not suitable transplant candidates. Recently, the clinical effects of TTR tetramer stabilizers, tafamidis and diflunisal, were demonstrated in randomized clinical trials, and tafamidis has been approved for the treatment of FAP in European countries and Japan. In addition, gene therapies with antisense oligonucleotides and small interfering RNAs are promising strategies to ameliorate TTR amyloidoses and are currently in clinical trials.. Liver transplantation to treat the familial TTR amyloidosis will likely be replaced by other less invasive therapies, such as TTR tetramer stabilizers and possibly gene therapy approaches. These newly developed therapies are expected to be effective for not only familial TTR amyloidosis but also SSA, based on their mechanisms of action.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Genetic Therapy; Humans; Liver Transplantation; Oligonucleotides, Antisense; Prealbumin; RNA, Small Interfering

Oral tafamidis (Vyndaqel(®)) is indicated in the EU for the treatment of transthyretin (TTR) amyloidosis in adult patients with early stage symptomatic polyneuropathy to delay peripheral neurologic impairment and, in Argentina, Japan and Mexico, for delaying the peripheral neurological impairment of TTR familial amyloid polyneuropathy (TTR-FAP). It is the first disease-modifying pharmacotherapy to be approved for use in adult patients with early-stage TTR-FAP. The drug acts to kinetically stabilize the variant TTR tetramer and thereby prevent tetramer dissociation, the rate-limiting step in TTR misfolding and amyloidogenesis. In the 18-month Fx-005 study in adult patients with early-stage V30M TTR-FAP, there were no statistically significant differences between tafamidis and placebo recipients for the coprimary endpoints, the Neuropathy Impairment Score-Lower Limb (NIS-LL) response rate (increase in NIS-LL score of <2) and the least-square mean change in Norfolk Quality-of-Life (QOL) Diabetic-Neuropathy Questionnaire total scores at 18 months, based on modified intent-to-treat analyses. However, in prespecified per-protocol analyses of efficacy evaluable patients, tafamidis recipients experienced significantly better outcomes in terms of these coprimary endpoints, with most (98%) tafamidis recipients showing stabilization of TTR tetramers at study end. Secondary endpoint outcomes also favoured tafamidis treatment over placebo. The beneficial effects of tafamidis in slowing deterioration of neurological function and health-related-QOL were maintained in long-term extension studies (up to 66 months). Tafamidis also stabilized TTR tetramers in patients with non-V30M TTR-FAP. Tafamidis was generally well tolerated, with most treatment-emergent adverse events being of mild to moderate intensity and very few patients discontinuing treatment because of these events. No new safety signals have emerged during long-term extension studies and post-marketing experience.

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Humans

Hereditary amyloid neuropathy includes hereditary ATTR, hereditary AGel, hereditary AApoAI, and hereditary Aβ2M amyloidosis. Among these diseases, hereditary ATTR is the most common type of amyloidosis caused by mutation in the transthyretin (TTR) gene. Hereditary ATTR amyloidosis is a life-threatening, multi-symptom, gain-of-toxic-function disease that may present with peripheral neuropathy, autonomic neuropathy, cardiomyopathy, ophthalmopathy, and/or leptomeningeal amyloidosis. In addition to the clinical symptoms described above, proven amyloid deposition in biopsy specimens and identification of disease-causing mutations in the TTR gene are necessary to establish the diagnosis. Deposition of amyloid in tissue can be demonstrated by Congo red staining of biopsy materials. Liver transplantation has been shown to be an effective therapeutic strategy for ameliorating hereditary ATTR amyloidosis, however, large numbers of patients are not suitable transplant candidates because of their age and/or advanced disease status. Recently, the clinical effects of TTR tetramer stabilizers, tafamidis and diflunisal, were demonstrated in randomised clinical trials, and tafamidis has been approved for the treatment of hereditary ATTR amyloidosis in European countries and in Japan. With the availability of disease-modifying therapies, early diagnosis and therapy become increasingly important in ATTR amyloidosis.

Topics: Adult; Age of Onset; Aged; Aged, 80 and over; Amyloid; Amyloid Neuropathies, Familial; Benzoxazoles; Diagnosis, Differential; Diflunisal; Early Diagnosis; Female; Genes, Dominant; Humans; Liver Transplantation; Male; Middle Aged; Mutation; Prealbumin

Patients with familial amyloidpolyneuropathies (FAP) require multidisciplinary neurologic and cardiologic management, including specific treatments to control the progression of systemic amyloidogenesis, symptomatic treatment of peripheral and autonomic neuropathies, and management of severe organ involvement (heart, eyes, kidneys). The first-line specific treatment of choice for met30 TTR-FAP is liver transplantation (LT) which suppresses the main source of mutant TTR, halts the progression of neuropathy in 70% of cases, and doubles the median survival time. Dual kidney-liver or heart-liver transplantation may be appropriate for patients with severe renal or cardiac failure. Tafamidis (Vyndaqel(R), Pfizer), a novel stabilizer of tetrameric TTR, has shown short-term effectiveness in slowing the progression of peripheral neuropathy in very early stages of met30 TTR-FAP This drug should thus be proposed for stage 1 symptomatic polyneuropathy. Other innovative medicines (RNA interference, antisense oligonucleotides) have been developed to block hepatic production of both mutant and wildtype TTR (noxious in late-onset forms of NAH after age 50 years), and to remove amyloid deposits (monoclonal anti-SAP). Clinical trials should first include patients with late-onset FAP or non-met30 TTR-FAP who are less responsive to LT7 and patients in whom Vyndaqel(R) is ineffective or inappropriate. Initial and periodic cardiac assessment is necessary, as cardiac impairment is inevitable and largely responsible for mortality. Symptomatic treatment is crucial to improve these patients' quality of life. Familial screening for carriers of the TTR gene mutation and regular clinical examination are essential to detect disease onset and to start specific therapy in a timely manner.

Topics: Amyloid Neuropathies, Familial; Antibodies, Monoclonal; Benzoxazoles; Clinical Trials as Topic; Diflunisal; Disease Progression; Doxycycline; Drug Therapy, Combination; Genetic Therapy; Heart Failure; Heart Transplantation; Humans; Kidney Failure, Chronic; Kidney Transplantation; Liver Transplantation; Myocardium; Oligonucleotides, Antisense; Renal Dialysis; RNA Interference; Serum Amyloid P-Component; Taurochenodeoxycholic Acid

Tafamidis meglumine (Vyndaqel®, Pfizer) is a novel, first-in-class drug for the treatment of transthyretin familial amyloid polyneuropathy (TTR-FAP), a rare neurodegenerative disorder characterized by progressive sensory, motor and autonomic impairment that is ultimately fatal. Pathogenic mutations in the transthyretin (TTR) protein lead to destabilization of its tetrameric structure and subsequent formation of amyloid aggregates. Tafamidis is a small-molecule inhibitor that binds selectively to TTR in human plasma and kinetically stabilizes the tetrameric structure of both wild-type TTR and a number of different mutants. Clinical trials indicate that tafamidis slows disease progression in patients with TTR-FAP and reduces the burden of disease, demonstrating improvement in small and large nerve fiber function, modified body mass index and lower extremity neurological examination. Tafamidis has been granted marketing authorization by the European Commission for the treatment of TTR-FAP and the U.S. Food and Drug Administration is currently reviewing this drug for the same indication.

Topics: Amyloid Neuropathies, Familial; Animals; Benzoxazoles; Genotype; Humans; Mutation; Neuroprotective Agents; Prealbumin; Randomized Controlled Trials as Topic

Patients with transthyretin amyloid cardiomyopathy (ATTR-CM) experience infiltrative cardiomyopathy and heart failure symptoms requiring costly hospitalizations. The Transthyretin Amyloidosis Cardiomyopathy Clinical Trial (ATTR-ACT) demonstrated the efficacy of tafamidis on the frequency of cardiovascular (CV)-related hospitalizations in patients with ATTR-CM.. As length of stay can affect the total hospitalization burden, our study aimed to better understand the impact of tafamidis on the number of CV-related hospital days avoided in the management of ATTR-CM patients.. Data from ATTR-ACT were used to calculate the total burden of CV-related hospitalization (days) by treatment arm in this post hoc analysis.. In the total trial population, patients receiving tafamidis had significantly fewer CV-related hospitalizations per year (relative risk reduction [RRR] 0.68; 0.4750 vs. 0.7025, p < 0.0001) and a shorter mean length of stay per CV-related hospitalization event (8.6250 vs. 9.5625 days) than patients receiving placebo. Taken together, tafamidis prevented 2.62 CV-related hospitalization days per patient per year. A subgroup analysis showed that with earlier treatment initiation of tafamidis, the annual number of CV-related hospitalizations was significantly lowered by 52% compared with placebo (RRR 0.48; 0.3378 vs. 0.7091, p < 0.0001). With 1.14 fewer days per hospitalization, tafamidis reduced the annual number of CV-related hospitalization days by 3.96 days per New York Heart Association class I/II patient.. In patients with ATTR-CM, tafamidis was associated with a lower rate of CV-related hospitalizations and shorter length of hospital stay. Timely diagnosis and treatment with tafamidis could further decrease the total number of CV-related hospitalization days per year.. NCT01994889.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Hospitalization; Humans; Prealbumin

The Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT) demonstrated the effectiveness of tafamidis for the treatment of patients with transthyretin amyloid cardiomyopathy (ATTR-CM). Tafamidis reduced mortality in all subgroups of patients studied. Tafamidis also reduced observed frequency of cardiovascular (CV)-related hospitalizations in all subgroups except those who were New York Heart Association (NYHA) class III at baseline who, paradoxically, had a higher frequency of CV-related hospitalizations than placebo. Given the greater mortality rate with placebo, this analysis assessed the impact of the confounding effect of death on the frequency of CV-related hospitalization in ATTR-ACT.. In ATTR-ACT, patients with ATTR-CM were randomized to tafamidis (n = 264) or placebo (n = 177) for 30 months. Post hoc analyses first defined and compared the effect of tafamidis treatment in the subset of NYHA class III patients from each treatment arm alive at month 30. The impact of a potential survivor bias was then adjusted for using principal stratification, estimating the frequency of CV-related hospitalization in NYHA class III patients who would have survived regardless of assigned treatment group (defined as the survivor average causal effect [SACE]).. In the subset of NYHA class III patients alive at month 30, tafamidis reduced the relative risk of CV-related hospitalization versus placebo (relative risk: 0.95 [95% CI: 0.55-1.65]). In the principal stratification analyses of those patients who would survive to 30 months regardless of treatment, tafamidis treatment was associated with a 24% lower risk of CV-related hospitalization (relative risk: 0.76 [95% CI: 0.45-1.24]). Similarly, there was a larger reduction in CV-related hospitalization frequency with tafamidis in NYHA class I or II patients in the SACE than was initially observed in ATTR-ACT.. Initial data from ATTR-ACT likely underestimated the effect of tafamidis on CV-related hospitalizations due to the confounding effect of death. When SACE was used to adjust for survivor bias, there was a 24% reduction in the frequency of CV-related hospitalization in NYHA class III patients treated with tafamidis.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Hospitalization; Humans; Prealbumin

The Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT) showed that tafamidis reduced all-cause mortality and cardiovascular-related hospitalizations in patients with transthyretin amyloid cardiomyopathy (ATTR-CM). This study aimed to estimate the impact of tafamidis on survival and quality-adjusted life-years (QALYs).. A multi-state, cohort, Markov model was developed to simulate the disease course of ATTR-CM throughout a lifetime. For survival extrapolation, survival curves were fitted by treatment arm and New York Heart Association (NYHA) Class I/II (68% of patients) and NYHA Class III (32% of patients) cohorts using the individual patient-level data from both the ATTR-ACT and the corresponding long-term extension study. Univariate and multivariate sensitivity analyses were conducted. The predicted mean survival for the total population (NYHA Class I/II + III) was 6.73 years for tafamidis and 2.85 years for the standard of care (SoC), resulting in an incremental mean survival of 3.88 years [95% confidence interval (CI) 1.32-5.66]. Of the 6.73 life-years, patients on tafamidis spend, on average, 4.82 years in NYHA Class I/II, while patients on SoC spend an average of 1.60 life-years in these classes. The combination of longer survival in lower NYHA classes produced a QALY gain of 5.39 for tafamidis and 2.11 for SoC, resulting in 3.29 incremental QALYs (95% CI 1.21-4.74) in favour of tafamidis.. Based on the disease simulation model results, tafamidis is expected to more than double the life expectancy and QALYs of ATTR-CM patients compared to SoC. Longer-term follow-up data from the ATTR-ACT extension study will further inform these findings.. NCT01994889 (date of registration: 26 November 2013).

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Prealbumin

Tafamidis is an effective treatment for transthyretin amyloid cardiomyopathy (ATTR-CM) in the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT). While ATTR-ACT was not designed for a dose-specific assessment, further analysis from ATTR-ACT and its long-term extension study (LTE) can guide determination of the optimal dose.. In ATTR-ACT, patients were randomized (2:1:2) to tafamidis 80 mg, 20 mg, or placebo for 30 months. Patients completing ATTR-ACT could enrol in the LTE (with placebo-treated patients randomized to tafamidis 80 or 20 mg; 2:1) and all patients were subsequently switched to high-dose tafamidis. All-cause mortality was assessed in ATTR-ACT combined with the LTE (median follow-up 51 months). In ATTR-ACT, the combination of all-cause mortality and cardiovascular-related hospitalizations over 30 months was significantly reduced with tafamidis 80 mg (P = 0.0030) and 20 mg (P = 0.0048) vs. placebo. All-cause mortality vs. placebo was reduced with tafamidis 80 mg [Cox hazards model (95% confidence interval): 0.690 (0.487-0.979), P = 0.0378] and 20 mg [0.715 (0.450-1.137), P = 0.1564]. The mean (standard error) change in N-terminal pro-B-type natriuretic peptide from baseline to Month 30 was -1170.51 (587.31) (P = 0.0468) with tafamidis 80 vs. 20 mg. In ATTR-ACT combined with the LTE there was a significantly greater survival benefit with tafamidis 80 vs. 20 mg [0.700 (0.501-0.979), P = 0.0374]. Incidence of adverse events in both tafamidis doses were comparable to placebo.. Tafamidis, both 80 and 20 mg, effectively reduced mortality and cardiovascular-related hospitalizations in patients with ATTR-CM. The longer-term survival data and the lack of dose-related safety concerns support tafamidis 80 mg as the optimal dose.. ClinicalTrials.gov NCT01994889; NCT02791230.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Heart Failure; Humans; Prealbumin

In the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial, tafamidis significantly reduced all-cause mortality and cardiovascular-related hospitalizations in patients with transthyretin amyloid cardiomyopathy (ATTR-CM). ATTR-CM is associated with a significant burden of disease; further analysis of patient-reported quality of life will provide additional data on the efficacy of tafamidis. In the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial, 441 adult patients with ATTR-CM were randomized (2:1:2) to tafamidis 80 mg, tafamidis 20 mg, or placebo for 30 months, with pooled tafamidis (80 mg and 20 mg) compared with placebo. Change in Kansas City Cardiomyopathy Questionnaire Overall Summary (KCCQ-OS) domain scores, EQ-5D-3L scores, and patient global assessment, were prespecified exploratory end points. A greater proportion of patients improved KCCQ-OS score at month 30 with tafamidis (41.8%) versus placebo (21.4%). Tafamidis significantly reduced the decline in all 4 KCCQ-OS domains (p <0.0001 for all), and in EQ-5D-3L utility (0.09 [confidence interval 0.05 to 0.12]; p <0.0001) and EQ visual analog scale (9.11 [confidence interval 5.39 to 12.83]; p <0.0001) scores at month 30 versus placebo. A larger proportion of tafamidis-treated patients reported their patient global assessment improved at month 30 (42.3% vs 23.8% with placebo). In conclusion, tafamidis effectively reduced the decline in patient-reported outcomes, providing further insight into its efficacy in health-related quality of life in patients with ATTR-CM.

Topics: Activities of Daily Living; Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Cost of Illness; Female; Humans; Male; Patient Reported Outcome Measures; Quality of Life; Self Efficacy; Social Participation

In the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT), tafamidis significantly reduced mortality and cardiovascular (CV)-related hospitalizations compared with placebo in patients with transthyretin amyloid cardiomyopathy (ATTR-CM). This analysis aimed to assess the causes of CV-related death and hospitalization in ATTR-ACT to provide further insight into the progression of ATTR-CM and efficacy of tafamidis. ATTR-ACT was an international, double-blind, placebo-controlled, and randomized study. Patients with hereditary or wild-type ATTR-CM were randomized to tafamidis (n = 264) or placebo (n = 177) for 30 months. The independent Endpoint Adjudication Committee determined whether certain investigator-reported events met the definition of disease-related efficacy endpoints using predefined criteria. Cause-specific reasons for CV-related deaths (heart failure [HF], arrhythmia, myocardial infarction, sudden death, stroke, and other CV causes) and hospitalizations (HF, arrhythmia, myocardial infarction, transient ischemic attack/stroke, and other CV causes) were assessed. Total CV-related deaths was 53 (20.1%) with tafamidis and 50 (28.2%) with placebo, with HF (15.5% tafamidis, 22.6% placebo), followed by sudden death (2.7% tafamidis, 5.1% placebo), the most common causes. The number of patients with a CV-related hospitalization was 138 (52.3%) with tafamidis and 107 (60.5%) with placebo; with HF the most common cause (43.2% tafamidis, 50.3% placebo). All predefined causes of CV-related death or hospitalization were less frequent with tafamidis than placebo. In conclusion, these data provide further insight into CV disease progression in patients with ATTR-CM, with HF the most common adjudicated cause of CV-related hospitalization or death in ATTR-ACT. Clinical trial registration ClinicalTrials.gov: NCT01994889.

Topics: Aged; Amyloid Neuropathies, Familial; Amyloidosis; Arrhythmias, Cardiac; Benzoxazoles; Cardiomyopathies; Cardiovascular Diseases; Cause of Death; Death, Sudden, Cardiac; Double-Blind Method; Female; Heart Failure; Hospitalization; Humans; Ischemic Attack, Transient; Male; Myocardial Infarction; Prealbumin; Proportional Hazards Models; Stroke

Tafamidis, a non-nonsteroidal anti-inflammatory benzoxazole derivative, acts as a transthyretin (TTR) stabilizer to slow progression of TTR amyloidosis (ATTR). Tafamidis meglumine, available as 20-mg capsules, is approved in more than 40 countries worldwide for the treatment of adults with early-stage symptomatic ATTR polyneuropathy. This agent, administered as an 80-mg, once-daily dose (4 × 20-mg capsules), is approved in the United States, Japan, Canada, and Brazil for the treatment of hereditary and wild-type ATTR cardiomyopathy in adults. An alternative single solid oral dosage formulation (tafamidis 61-mg free acid capsules) was developed and introduced for patient convenience (approved in the United States, United Arab Emirates, and European Union). In this single-center, open-label, randomized, 2-period, 2-sequence, crossover, multiple-dose phase 1 study, the rate and extent of absorption were compared between tafamidis 61-mg free acid capsules (test) and tafamidis meglumine 80-mg (4 × 20-mg) capsules (reference) after 7 days of repeated oral dosing under fasted conditions in 30 healthy volunteers. Ratios of adjusted geometric means (90%CI) for the test/reference formulations were 102.3 (98.0-106.8) for area under the concentration-time profile over the dosing interval and 94.1 (89.1-99.4) for the maximum observed concentration, satisfying prespecified bioequivalence acceptance criteria (90%CI, 80-125). Both tafamidis regimens had an acceptable safety/tolerability profile in this population.

Topics: Administration, Oral; Adult; Amyloid Neuropathies; Amyloid Neuropathies, Familial; Benzoxazoles; Brazil; Canada; Cardiomyopathies; Cross-Over Studies; Disease Progression; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Compounding; Fasting; Female; Healthy Volunteers; Humans; Japan; Male; Middle Aged; Prealbumin; Safety; Therapeutic Equivalency; United States

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Female; Humans; Male; Middle Aged; Quality of Life; RNA, Small Interfering; Surveys and Questionnaires

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Case-Control Studies; Echocardiography; Hospitalization; Humans; Mutation; Placebos; Prealbumin; Survival Analysis

To better characterize the effects of tafamidis in non-Val30Met patients with transthyretin familial amyloid polyneuropathy, this post hoc analysis compared the neurological results from a 12-month, open-label study of non-Val30Met versus Val30Met patients at month 12 from the 18-month, double-blind, placebo-controlled registration study. A baseline covariate adjusted analysis was used to control for differences in baseline neurological severity.. Neurological function was assessed using the Neuropathy Impairment Score - Lower Limbs (NIS-LL) in three cohorts: Val30Met tafamidis (n = 64), Val30Met placebo (n = 61) and non-Val30Met tafamidis (n = 21). The change in NIS-LL from baseline to month 12 for Val30Met and non-Val30Met tafamidis-treated patients was compared with the change from baseline at month 12 for Val30Met placebo-treated patients using a mixed-effects model for repeated measures (MMRM).. The baseline adjusted mean (standard error) change in NIS-LL values at month 12 was similar for Val30Met [1.60 (0.78)] and non-Val30Met [1.62 (1.43)] tafamidis-treated patients and less than that observed in the Val30Met placebo-treated group [4.72 (0.77); P = 0.0055 for Val30Met and P = 0.0592 for non-Val30Met]. Based on the MMRM, the magnitude of change in both tafamidis-treated cohorts was similar across the range of observed baseline NIS-LL values, and was consistently less than that observed in the Val30Met placebo-treated group at month 12.. This baseline-adjusted analysis demonstrated that tafamidis treatment delayed neurological progression comparably in Val30Met and non-Val30Met patients across a range of baseline NIS-LL values. Neurological progression in these two genotype groups may be more similar than previously considered.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Double-Blind Method; Female; Genotype; Humans; Lower Extremity; Male; Middle Aged; Mutation; Treatment Outcome

Transthyretin amyloid cardiomyopathy is caused by the deposition of transthyretin amyloid fibrils in the myocardium. The deposition occurs when wild-type or variant transthyretin becomes unstable and misfolds. Tafamidis binds to transthyretin, preventing tetramer dissociation and amyloidogenesis.. In a multicenter, international, double-blind, placebo-controlled, phase 3 trial, we randomly assigned 441 patients with transthyretin amyloid cardiomyopathy in a 2:1:2 ratio to receive 80 mg of tafamidis, 20 mg of tafamidis, or placebo for 30 months. In the primary analysis, we hierarchically assessed all-cause mortality, followed by frequency of cardiovascular-related hospitalizations according to the Finkelstein-Schoenfeld method. Key secondary end points were the change from baseline to month 30 for the 6-minute walk test and the score on the Kansas City Cardiomyopathy Questionnaire-Overall Summary (KCCQ-OS), in which higher scores indicate better health status.. In the primary analysis, all-cause mortality and rates of cardiovascular-related hospitalizations were lower among the 264 patients who received tafamidis than among the 177 patients who received placebo (P<0.001). Tafamidis was associated with lower all-cause mortality than placebo (78 of 264 [29.5%] vs. 76 of 177 [42.9%]; hazard ratio, 0.70; 95% confidence interval [CI], 0.51 to 0.96) and a lower rate of cardiovascular-related hospitalizations, with a relative risk ratio of 0.68 (0.48 per year vs. 0.70 per year; 95% CI, 0.56 to 0.81). At month 30, tafamidis was also associated with a lower rate of decline in distance for the 6-minute walk test (P<0.001) and a lower rate of decline in KCCQ-OS score (P<0.001). The incidence and types of adverse events were similar in the two groups.. In patients with transthyretin amyloid cardiomyopathy, tafamidis was associated with reductions in all-cause mortality and cardiovascular-related hospitalizations and reduced the decline in functional capacity and quality of life as compared with placebo. (Funded by Pfizer; ATTR-ACT ClinicalTrials.gov number, NCT01994889 .).

Topics: Administration, Oral; Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Disease Progression; Double-Blind Method; Female; Heart Failure; Hospitalization; Humans; Male; Middle Aged; Prealbumin; Quality of Life; Survival Analysis; Walk Test

Tafamidis, a non-NSAID highly specific transthyretin stabilizer, delayed neurologic disease progression as measured by Neuropathy Impairment Score-Lower Limbs (NIS-LL) in an 18-month, double-blind, placebo-controlled randomized trial in 128 patients with early-stage transthyretin V30M familial amyloid polyneuropathy (ATTRV30M-FAP). The current post hoc analyses aimed to further evaluate the effects of tafamidis in delaying ATTRV30M-FAP progression in this trial.. Pre-specified, repeated-measures analysis of change from baseline in NIS-LL in this trial (ClinicalTrials.gov NCT00409175) was repeated with addition of baseline as covariate and multiple imputation analysis for missing data by treatment group. Change in NIS-LL plus three small-fiber nerve tests (NIS-LL + Σ3) and NIS-LL plus seven nerve tests (NIS-LL + Σ7) were assessed without baseline as covariate. Treatment outcomes over the NIS-LL, Σ3, Σ7, modified body mass index and Norfolk Quality of Life-Diabetic Neuropathy Total Quality of Life Score were also examined using multivariate analysis techniques.. Neuropathy progression based on NIS-LL change from baseline to Month 18 remained significantly reduced for tafamidis versus placebo in the baseline-adjusted and multiple imputation analyses. NIS-LL + Σ3 and NIS-LL + Σ7 captured significant treatment group differences. Multivariate analyses provided strong statistical evidence for a superior tafamidis treatment effect.. These supportive analyses confirm that tafamidis delays neurologic progression in early-stage ATTRV30M-FAP.. NCT00409175.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Female; Humans; Male; Middle Aged; Polyneuropathies; Prealbumin; Treatment Outcome

Topics: Adult; Amyloid; Amyloid Neuropathies, Familial; Benzoxazoles; Biomarkers; Creatinine; Cystatin C; Drug Administration Schedule; Female; Gene Expression; Glomerular Filtration Rate; Humans; Kidney; Male; Middle Aged; Mutation; Nephritis; Prealbumin; Prospective Studies; Proteinuria

The objective of the present study was to evaluate the long-term safety and efficacy of tafamidis in treating hereditary transthyretin amyloid polyneuropathy.. A prospectively planned interim analysis was conducted on an on-going, phase III, open-label extension study following an 18-month, randomized, controlled study and 12-month, open-label extension study in ATTRV30M patients and a single-arm, open-label study in non-ATTRV30M patients. Thirty-seven ATTRV30M patients received placebo for 18 months, then switched to tafamidis and 38 ATTRV30M patients and 18 non-ATTRV30M patients continuously received tafamidis from day 1, up to 6 years.. Long-term tafamidis was associated with a favourable safety/tolerability profile, without any unexpected adverse events. Patients initiating tafamidis at the start of the randomized study had less polyneuropathy progression versus those switching to tafamidis following 18 months of placebo and were less likely to progress to the next ambulatory stage after up to 6 years follow-up. In the patients who switched from placebo to tafamidis, polyneuropathy progression and deterioration in quality of life slowed significantly during long-term tafamidis treatment as compared with the previous placebo treatment. In non-ATTRV30M patients, some polyneuropathy progression was observed across all efficacy measures.. These data provide evidence for the long-term (up to 6 years) safety and efficacy of tafamidis.ClinicalTrials.gov: NCT00925002.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Female; Humans; Longitudinal Studies; Male; Middle Aged; Quality of Life

The efficacy and safety of tafamidis in transthyretin (TTR) familial amyloid polyneuropathy (TTR-FAP) were evaluated in this open-label study.. Japanese TTR-FAP patients (n=10; mean age 60.1 years) received tafamidis meglumine (20mg daily; median treatment duration 713.5 days). The primary endpoint was TTR stabilization at Week 8. Secondary endpoints included Neuropathy Impairment Score-Lower Limb (NIS-LL), Norfolk QOL-DN total quality of life (TQOL), and modified body mass index (mBMI).. TTR stabilization was achieved in all patients at Weeks 8 and 26, 9 out of 10 patients at Week 52, and 8 out of 10 patients at Week 78. The percentage (95% CI) of NIS-LL responders (increase from baseline in NIS-LL<2) was 80.0% (44.4, 97.5), 60.0% (26.2, 87.8), and 40.0% (12.2, 73.8) and mean(SD) NIS-LL change from baseline was 2.1 (5.6), 3.6 (4.4), and 3.3 (4.7), at Weeks 26, 52, and 78, respectively. Mean (SD) changes from baseline in TQOL and mBMI at Weeks 26, 52, and 78 were 11.8 (20.0), 9.1 (12.5), and 10.8 (13.7) for TQOL, and 26.6 (61.9), 64.9 (80.0), and 53.7 (81.4) for mBMI, respectively. Ambulation status was preserved in 4 out of 8 patients at Week 78. Most adverse events (AEs) were mild/moderate, with no discontinuations due to AEs.. Tafamidis stabilized TTR, was safe and well-tolerated, and was effective over 1.5 years in slowing neurologic progression and maintaining TQOL and nutrition status in TTR-FAP.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Body Mass Index; Echocardiography; Female; Follow-Up Studies; Humans; Japan; Male; Methionine; Middle Aged; Pharmacogenetics; Prealbumin; Valine; Young Adult

ClincalTrials.gov Identifier: NCT00409175, NCT00791492, and NCT00925002.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Anti-Inflammatory Agents, Non-Steroidal; Benzoxazoles; Double-Blind Method; Drug Administration Schedule; Female; Humans; Male; Middle Aged; Prospective Studies; Secondary Prevention

A phase 2, open-label study in 21 patients with non-Val30Met and non-Val122Ile hereditary transthyretin amyloidosis showed that tafamidis (20 mg daily for 12 months) stabilized these transthyretin variants. We assessed cardiac amyloid infiltration and cardiac abnormalities in this same study population. At baseline, median age was 64.3 years, 11 patients were in NYHA class II, 13 had conduction abnormalities, 14 N-terminal pro-hormone brain natriuretic peptide concentrations >300 pg/ml, and 17 interventricular septal thickness >12 mm. Mean (SD) left ventricular ejection fraction was 60.3% (9.96). Patients with normal heart rate variability increased from 4/19 at baseline to 8/19 at month 12 (p < 0.05). Cardiac biomarkers remained stable. Although four patients had increases in interventricular septal thickness ≥ 2 mm, the remainder had stable septal wall thickness. There were no clinically relevant changes in mean echocardiographic/electrocardiographic variables and no safety concerns.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Europe; Female; Fibrosis; Genetic Predisposition to Disease; Heart Failure; Humans; Male; Middle Aged; Mutation; Myocardium; Phenotype; Prealbumin; Risk Factors; Time Factors; Treatment Outcome; United States

Transthyretin (TTR) amyloidosis is a progressive systemic disorder caused by misfolded TTR monomers that cumulatively deposit in the heart and systemically as amyloid.. This phase 2 open-label trial evaluated the stabilization of TTR tetramers using 20 mg of tafamidis daily at week 6 (primary end point), month 6, and month 12, as well as safety of tafamidis treatment and efficacy with respect to progression of TTR amyloid cardiomyopathy. Thirty-one wild-type patients (median age, 76.7 years; 93.5% men) with a median disease duration of 55.6 months and mild to moderate heart failure (96.8%; New York Heart Association, classes I-II) were enrolled. Thirty of 31 patients (96.8%) achieved TTR stabilization after 6 weeks and 25 of 28 patients (89.3%) after 12 months. After 12 months of treatment, 3 patients discontinued prematurely, 2 patients died, 7 patients were hospitalized because of cardiovascular events, 20 of 28 patients demonstrated preserved New York Heart Association classification status, but 15 of 31 (48.4%) patients had clinical progression (eg, admission for cardiac failure, atrial fibrillation, and syncope). N-terminal prohormone brain natriuretic peptide levels did not increase significantly over time, troponin I and troponin T increased moderately, and no consistent clinically relevant changes were seen in echocardiographic cardiac assessments. Tafamidis treatment was generally well tolerated although 7 of 31 patients had bouts of diarrhea.. Tafamidis treatment effectively achieved and maintained TTR stabilization and was well tolerated. The absence of significant changes in most biochemical and echocardiographic parameters suggests that further evaluation of tafamidis in TTR amyloid cardiomyopathy is warranted.. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00694161.

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Disease Progression; Drug Administration Schedule; Female; Humans; Male; Mutation; Myocardium; Prealbumin; Protein Folding; Protein Multimerization; Protein Stability; Protein Structure, Quaternary; Time Factors; Treatment Outcome; United States

The aim of this study was to assess the effect of Tafamidis, which slows the progression of early stages of Met30 transthyretin (TTR) familial amyloidosis polyneuropathy (FAP) in more advanced cases.. The study was a prospective, non-randomized controlled trial carried out at the French national reference centre for FAP with follow-up at 1 year. Thirty-seven consecutive Met30-TTR-FAP patients were enrolled between December 2009 and July 2011, with NIS-LL (Neuropathy Impairment Score-lower limbs) > 10 and Karnofsky score > 60. Their mean (SD) age was 56.4 (19) years. Seventy-seven per cent of patients had a walking disability. Seven patients (19%) were withdrawn for adverse effects. The primary study outcome measurements, planned before data collection began, were NIS-LL and NIS-UL (upper limbs) scores and disability scores.. Of the 37 patients entered into the study, 29 were evaluated at 6 months and 13 at 12 months. During the first 6 months of treatment, the mean progression of NIS-LL score was 4.8 and was similar to that during the period before treatment. Among the 45% of patients without NIS-LL progression, the NIS-UL score worsened in 55%. During the first year, 55% deteriorated with respect to disability and 38% with respect to NIS only; only two patients (7%) remained stable. Four (out of 20; 20%) patients who were previously stage 1 reached stage 2 (walking with aid) after this period. Two out of nine patients who were initially normotensive developed orthostatic hypotension. There were a total of 19 adverse events, including four febrile urinary tract infections and three severe diarrhoeas, with faecal incontinence in two.. In most patients with advanced Met30 TTR-FAP, Tafamidis is not able to stop disease progression, in respect of both NIS-LL and disability. Other anti-amyloid medicines should be assessed in this context.

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Humans; Middle Aged

Tafamidis, a transthyretin (TTR) kinetic stabilizer, delayed neuropathic progression in patients with Val30Met TTR familial amyloid polyneuropathy (TTR-FAP) in an 18-month randomized controlled trial (study Fx-005). This 12-month, open-label extension study evaluated the long-term safety, tolerability, and efficacy of tafamidis 20 mg once daily in 86 patients who earlier received blinded treatment with tafamidis or placebo. Efficacy measures included the Neuropathy Impairment Score in the Lower Limbs (NIS-LL), Norfolk Quality of Life-Diabetic Neuropathy total quality of life (TQOL) score, and changes in neurologic function and nutritional status. We quantified the monthly rates of change in efficacy measures, and TTR stabilization, and monitored adverse events (AEs). Patients who continued on tafamidis had stable rates of change in NIS-LL (from 0.08 to 0.11/month; p = 0.60) and TQOL (from -0.03 to 0.25; p = 0.16). In patients switched from placebo, the monthly rate of change in NIS-LL declined (from 0.34 to 0.16/month; p = 0.01), as did TQOL score (from 0.61 to -0.16; p < 0.001). Patients treated with tafamidis for 30 months had 55.9 % greater preservation of neurologic function as measured by the NIS-LL than patients in whom tafamidis was initiated later. Plasma TTR was stabilized in 94.1 % of patients treated with tafamidis for 30 months. AEs were similar between groups; no patients discontinued because of an AE. Long-term tafamidis was well tolerated, with the reduced rate of neurologic deterioration sustained over 30 months. Tafamidis also slowed neurologic impairment in patients previously given placebo, but treatment benefits were greater when tafamidis was begun earlier.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Drug Administration Schedule; Female; Follow-Up Studies; Humans; International Cooperation; Male; Methionine; Middle Aged; Mutation; Prealbumin; Quality of Life; Time Factors; Valine; Young Adult

This phase II, open-label, single-treatment arm study evaluated the pharmacodynamics, efficacy, and safety of tafamidis in patients with non-Val30Met transthyretin (TTR) amyloidosis. Twenty-one patients with eight different non-Val30Met mutations received 20 mg QD of tafamidis meglumine for 12 months. The primary outcome, TTR stabilization at Week 6, was achieved in 18 (94.7%) of 19 patients with evaluable data. TTR was stabilized in 100% of patients with non-missing data at Months 6 (n = 18) and 12 (n = 17). Exploratory efficacy measures demonstrated some worsening of neurological function. However, health-related quality of life, cardiac biomarker N-terminal pro-hormone brain natriuretic peptide, echocardiographic parameters, and modified body mass index did not demonstrate clinically relevant worsening during the 12 months of treatment. Tafamidis was well tolerated. In conclusion, our findings suggest that tafamidis 20 mg QD effectively stabilized TTR associated with several non-Val30Met variants.

Topics: Adult; Aged; Amyloid; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Europe; Female; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Mutation; Phenotype; Prealbumin; Time Factors; Treatment Outcome; United States

To evaluate the efficacy and safety of 18 months of tafamidis treatment in patients with early-stage V30M transthyretin familial amyloid polyneuropathy (TTR-FAP).. In this randomized, double-blind trial, patients received tafamidis 20 mg QD or placebo. Coprimary endpoints were the Neuropathy Impairment Score-Lower Limbs (NIS-LL) responder analysis (<2-point worsening) and treatment-group difference in the mean change from baseline in Norfolk Quality of Life-Diabetic Neuropathy total score (TQOL) in the intent-to-treat (ITT) population (n = 125). These endpoints were also evaluated in the efficacy-evaluable (EE; n = 87) population. Secondary endpoints, including changes in neurologic function, nutritional status, and TTR stabilization, were analyzed in the ITT population.. There was a higher-than-anticipated liver transplantation dropout rate. No differences were observed between the tafamidis and placebo groups for the coprimary endpoints, NIS-LL responder analysis (45.3% vs 29.5% responders; p = 0.068) and change in TQOL (2.0 vs 7.2; p = 0.116) in the ITT population. In the EE population, significantly more tafamidis patients than placebo patients were NIS-LL responders (60.0% vs 38.1%; p = 0.041), and tafamidis patients had better-preserved TQOL (0.1 vs 8.9; p = 0.045). Significant differences in most secondary endpoints favored tafamidis. TTR was stabilized in 98% of tafamidis and 0% of placebo patients (p < 0.0001). Adverse events were similar between groups.. Although the coprimary endpoints were not met in the ITT population, tafamidis was associated with no trend toward more NIS-LL responders and a significant reduction in worsening of most neurologic variables, supporting the hypothesis that preventing TTR dissociation can delay peripheral neurologic impairment.. This study provides Class II evidence that 20 mg tafamidis QD was associated with no difference in clinical progression in patients with TTR-FAP, as measured by the NIS-LL and the Norfolk QOL-DN score. Secondary outcomes demonstrated a significant delay in peripheral neurologic impairment with tafamidis, which was well tolerated over 18 months.

Topics: Adolescent; Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Double-Blind Method; Humans; Male; Middle Aged; Neuroprotective Agents; Polymorphism, Single Nucleotide; Prealbumin; Quality of Life; Severity of Illness Index

The purpose of this study was to carefully analyse the therapeutic benefit of tafamidis in patients with wild-type transthyretin amyloidosis (ATTRwt) and cardiomyopathy (ATTRwt-CM) after one year of therapy based on serial multi-parametric cardiovascular magnetic resonance (CMR) imaging.. Non-sponsored data based on multi-parametric CMR regarding the effect of tafamidis on the cardiac phenotype of patients with ATTRwt-CM are not available so far.. The present study comprised N = 40 patients with ATTRwt-CM who underwent two serial multi-parametric CMR studies within a follow-up period of 12 ± 3 months. Baseline (BL) clinical parameters, serum biomarkers and CMR findings were compared to follow-up (FU) values in patients treated "with" tafamidis 61 mg daily (n = 20, group A) and those "without" tafamidis therapy (n = 20, group B). CMR studies were performed on a 1.5-T system and comprised cine-imaging, pre- and post-contrast T1-mapping and additional calculation of extracellular volume fraction (ECV) values.. While left ventricular ejection fraction (LV-EF), left ventricular mass index (LVMi), left ventricular wall thickness (LVWT), native T1- and ECV values remained unchanged in the tafamidis group A, a slight reduction in LV-EF (p = 0.003) as well as a subtle increase in LVMi (p = 0.034), in LVWT (p = 0.001), in native T1- (p = 0.038) and ECV-values (p = 0.017) were observed in the untreated group B. Serum NT-proBNP levels showed an overall increase in both groups, however, with the untreated group B showing a relatively higher increase compared to the treated group A. Assessment of NYHA class did not result in significant intra-group differences when BL were compared with FU, but a trend to improvement in the treated group A compared to a worsening trend in the untreated group B (∆p = 0.005).. As expected, tafamidis does not improve cardiac phenotype in patients with ATTRwt-CM after one year of therapy. However, tafamidis seems to slow down cardiac disease progression in patients with ATTRwt-CM compared to those without tafamidis therapy based on multi-parametric CMR data already after one year of therapy.

Topics: Amyloid Neuropathies, Familial; Cardiomyopathies; Humans; Magnetic Resonance Imaging; Magnetic Resonance Imaging, Cine; Magnetic Resonance Spectroscopy; Myocardium; Predictive Value of Tests; Stroke Volume; Ventricular Function, Left

TTR aggregation causes hereditary transthyretin (TTR) polyneuropathy (ATTRv-PN) in individuals with destabilised TTR variants. ATTRv-PN can be treated with ligands that bind TTR and prevent aggregation. One such ligand, tafamidis, is widely approved to treat ATTRv-PN. We explore how TTR stabilisation markers relate to clinical efficacy in 210 ATTRv-PN patients taking tafamidis.. TTR concentration in patient plasma was measured before and after tafamidis treatment using assays for native or combined native + non-native TTR. TTR tetramer dissociation kinetics, which are slowed by tafamidis binding, were also measured.. Native TTR levels increased by 56.8% while combined native + non-native TTR levels increased by 3.1% after 24 months of tafamidis treatment, implying that non-native TTR decreased. Accordingly, the fraction of native TTR increased from 0.54 to 0.71 with tafamidis administration. Changes in native and non-native TTR levels were uncorrelated with clinical response to tafamidis. TTR tetramer dissociation generally slowed to an extent consistent with ∼40% of TTR being tafamidis-bound. Male non-responders had a lower extent of binding.. Native and non-native TTR concentration changes cannot be used as surrogate measures for therapeutic efficacy. Also, successful tafamidis therapy requires only moderate TTR stabilisation. Male patients may benefit from higher tafamidis doses.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Male; Polyneuropathies; Prealbumin

Tafamidis inhibits progression of transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) by binding TTR tetramer and inhibiting dissociation to monomers capable of denaturation and deposition in cardiac tissue. While the phase 3 ATTR-ACT trial demonstrated the efficacy of tafamidis, the degree to which the approved dose captures the full potential of the mechanism has yet to be assessed.. We developed a model of dynamic TTR concentrations in plasma to relate TTR occupancy by tafamidis to TTR stabilisation. We then developed population pharmacokinetic-pharmacodynamic models to characterise the relationship between stabilisation and measures of disease progression.. Modelling individual patient data of tafamidis exposure and increased plasma TTR confirmed that single-site binding provides complete tetramer stabilisation. These findings support the value of TTR stabilisation as a clinically beneficial treatment option in ATTR-CM and the ability of tafamidis to realise nearly the full therapeutic benefit of this mechanism.. NCT01994889.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Disease Progression; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Amyloidosis; Cardiomyopathies; Diphosphates; Heart Failure; Humans; Prealbumin; Radionuclide Imaging; Radiopharmaceuticals; Technetium

A recently published expert consensus document recommended a multiparametric tool to monitor cardiac disease progression in patients with transthyretin cardiac amyloidosis (ATTR-CA). We aimed to evaluate the effect of the transthyretin stabiliser drug, tafamidis, by applying this integrative tool.. We retrospectively applied a multiparametric tool in a group of ATTR-CA patients who were given tafamidis between the years 2019-2021 and were followed in a dedicated clinic. We used three pre-specified follow-up timepoints: at 6, 12 and 18 months.. Based on a multiparametric tool, the use of tafamidis promoted disease stabilisation in the majority of patients at 18-month follow-up. Further study should focus on monitoring disease improvement in patients with ATTR-CA.

Topics: Amyloid Neuropathies, Familial; Cardiomyopathies; Consensus; Disease Progression; Humans; Prealbumin; Retrospective Studies

Hereditary transthyretin (TTR) amyloidosis (ATTRv) initially presents as a polyneuropathy and/or a cardiomyopathy. Central nervous system (CNS) pathology in ATTRv amyloidosis, including focal neurological episodes, dementia, cerebrovascular bleeding, and seizures, appears around a decade later. Wild-type (WT) TTR amyloidosis (ATTRwt) causes a cardiomyopathy. CNS pathology risk likely also increases in these patients as cardiomyopathy progresses. Herein, we study tafamidis-mediated TTR kinetic stabilisation in cerebrospinal fluid (CSF).. Varying tafamidis concentrations (50-1000 nM) were added to CSF from healthy donors or ATTRv patients, and TTR stabilisation was measured. Tafamidis meglumine (Vyndaqel) can be dosed at 20 or 80 mg QD. The latter dose is bioequivalent to a 61 mg QD dose of tafamidis free acid (Vyndamax). The tafamidis CSF concentration in ATTRv patients on 20 mg Vyndaqel is ∼125 nM. By linear extrapolation, we expect a CSF concentration of ∼500 nM at the higher dose. When tafamidis is added to healthy donor CSF at 125 or 500 nM, the WT TTR dissociation rate decreases by 42% or 87%, respectively.. Tafamidis stabilises TTR in CSF to what is likely a clinically meaningful extent at CSF concentrations achieved by the normal tafamidis dosing regimen.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Prealbumin

By stabilizing transthyretin, tafamidis delays progression of amyloidosis due to transthyretin variant (ATTRv) and replaced liver transplantation (LT) as the first-line therapy. No study compared these two therapeutic strategies.. In a monocentric retrospective cohort analysis, patients with ATTRv amyloidosis treated with either tafamidis or LT were compared using a propensity score and a competing risk analysis for three endpoints: all-cause mortality, cardiac worsening (heart failure or cardiovascular death) and neurological worsening (worsening in PolyNeuropathy Disability score).. 345 patients treated with tafamidis (. ATTRv amyloidosis patients treated with tafamidis would present a better survival but also a faster deterioration of their cardiac and neurological statuses as compared with LT. Further studies are needed to clarify the therapeutic strategy in ATTRv amyloidosis.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Liver Transplantation; Middle Aged; Prealbumin; Retrospective Studies

The efficacy of a therapy for patients with transthyretin amyloid cardiomyopathy (ATTR-CM) has not been proven, but tafamidis has been associated with favorable outcomes. However, echocardiographic details of the association of tafamidis with cardiac morphology remain undetermined. Moreover, whether the efficacy of tafamidis varies with the degree of cardiac involvement remains unknown. Using echocardiography, this study investigated the impact of tafamidis on the cardiac morphology of patients with ATTR-CM.Methods and Results: Of 52 consecutive patients with biopsy-proven ATTR-CM at Kobe University Hospital, we included 41 for whom details of follow-up echocardiographic examinations after the administration of tafamidis were available. All patients underwent standard and speckle-tracking echocardiography before and a mean (±SD) of 16±8 months after the administration of tafamidis. No significant changes were observed in any representative echocardiographic parameters after the administration of tafamidis. Furthermore, there were no significant changes observed in subgroup analyses (e.g., left ventricular [LV] ejection fraction ≥50% vs. <50%; LV mass index <150 vs. ≥150 g/m. Tafamidis may prevent worsening of various representative echocardiographic parameters of patients with ATTR-CM. This effect is also seen in patients with relatively advanced disease and in those who are elderly.

Topics: Aged; Amyloid Neuropathies, Familial; Cardiomyopathies; Echocardiography; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Amyloidosis; Cardiomyopathies; Diphosphates; Humans; Prealbumin; Predictive Value of Tests

Tafamidis treatment positively affects left ventricular (LV) structure and function and improves outcomes in patients with transthyretin amyloid cardiomyopathy (ATTR-CM). We aimed to investigate the relationship between treatment response and cardiac amyloid burden identified by serial quantitative 99mTc-DPD SPECT/CT. We furthermore aimed to identify nuclear imaging biomarkers that could be used to quantify and monitor response to tafamidis therapy.. Forty wild-type ATTR-CM patients who underwent 99mTc-DPD scintigraphy and SPECT/CT imaging at baseline and after treatment with tafamidis 61 mg once daily [median, 9.0 months (interquartile range 7.0-10.0)] were divided into two cohorts based on the median (-32.3%) of the longitudinal percent change in standardized uptake value (SUV) retention index. ATTR-CM patients with a reduction greater than or equal to the median (n = 20) had a significant decrease in SUV retention index (P < 0.001) at follow-up, which translated into significant benefits in serum N-terminal prohormone of brain natriuretic peptide levels (P = 0.006), left atrial volume index (P = 0.038), as well as LV [LV global longitudinal strain: P = 0.028, LV ejection fraction (EF): P = 0.027, LV cardiac index (CI): P = 0.034] and right ventricular (RV) [RVEF: P = 0.025, RVCI: P = 0.048] functions compared with patients with a decrease less than the median (n = 20).. Treatment with tafamidis in ATTR-CM patients results in a significant reduction in SUV retention index, associated with significant benefits for LV and RV function and cardiac biomarkers. Serial quantitative 99mTc-DPD SPECT/CT imaging with SUV may be a valid tool to quantify and monitor response to tafamidis treatment in affected patients.. 99mTc-DPD SPECT/CT imaging with determination of SUV retention index as part of a routine annual examination can provide evidence of treatment response in ATTR-CM patients receiving disease-modifying therapy. Further long-term studies with 99mTc-DPD SPECT/CT imaging may help to evaluate the relationship between tafamidis-induced reduction in SUV retention index and outcome in patients with ATTR-CM and will demonstrate whether highly disease-specific 99mTc-DPD SPECT/CT imaging is more sensitive than routine diagnostic monitoring.

Topics: Amyloid Neuropathies, Familial; Amyloidosis; Cardiomyopathies; Humans; Prealbumin; Single Photon Emission Computed Tomography Computed Tomography

Cardiac transthyretin amyloidosis is an infiltrative cardiomyopathy with high mortality. To date, there are no specific biomarkers to directly assess disease activity and response to specific treatments. Our aim was to evaluate scintigraphic changes after treatment with the transthyretin stabilizer tafamidis.

Topics: Amyloid Neuropathies, Familial; Cardiomyopathies; Humans; Organotechnetium Compounds; Prealbumin

The transthyretin kinetic stabilizer tafamidis, used as a first-line therapy of amyloidosis patients, binds selectively to the transthyretin protein structure and thus prevents its dissociation. The limited information regarding tafamidis application in Glu89Gln amyloidosis patients imposed our research team to determine and evaluate its individual mean plasma levels and their biological variation.. The present cohort study investigated Bulgarian amyloidosis patients, grouped by gender, age, and therapy duration. A total of sixty patients aged 40-75 years and therapy duration up to 9 years were included. A precise and accurate high-performance liquid chromatography method with ultraviolet detection was used for plasma concentration measurement.. Mean plasma concentrations were 5.13 ± 2.64 µmol/L and showed low intra-individual (18.50%) and high inter-individual variability (51.43%). No significant difference was observed between tafamidis plasma levels and therapy duration with p = 0.5941 (p < 0.05 considered significant), but a significant positive correlation was found between plasma concentration, gender, and age with obtained results about p-value 0.0001 and 0.0235, respectively.. The summary results of the study showed differences that may be based on some specific clinical features of the Glu89Gln mutation.

Topics: Amyloid Neuropathies, Familial; Cohort Studies; Humans; Mutation; Prealbumin

Under certain conditions, numerous soluble proteins possess an inherent tendency to convert into insoluble amyloid aggregates, which are associated with several sporadic and genetic human diseases. Transthyretin (TTR) is one of the more than 30 human amyloidogenic proteins involved in conditions such as senile systemic amyloidosis, familial amyloid polyneuropathy, and familial amyloid cardiomyopathy. Considerable effort has been focused on identifying the native tetrameric TTR stabilizers to inhibit rate-limiting tetramer dissociation and, consequently, ameliorate TTR amyloidogenesis. Here, we describe the design and synthesis of quinolin-2(1H)-one derivatives that could be structurally complementary to the thyroxine-binding site within tetrameric TTR. Among these quinolin-2(1H)-one derivatives, compound 7a allowed 16.7% of V30M-TTR (3.6 μM) fibril formation at the same concentration and 49.6% at a concentration of 1.8 μM. Compound 7a exhibited much greater potency in complex biological samples like human plasma than that observed with tafamidis, the drug approved for the treatment of TTR amyloid cardiomyopathy for wild-type or hereditary TTR-mediated amyloidosis. Furthermore, the unique spectral properties of compound 7a demonstrated its high potential for TTR quantification, imaging sensors, and fluorescent tools to study the mechanism of TTR amyloidogenesis.

Topics: Amyloid Neuropathies, Familial; Animals; Crystallography, X-Ray; Dose-Response Relationship, Drug; Fluorescence; Humans; Molecular Docking Simulation; Molecular Structure; Quinolones; Rats; Spectrometry, Fluorescence; Structure-Activity Relationship

This plain language summary describes the results of a study called ATTR-ACT, which was published in the

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Heart Failure; Humans; Language; Prealbumin; Quality of Life

Tafamidis is approved in many countries for the treatment of transthyretin amyloid cardiomyopathy. This study reports data on the long-term efficacy of tafamidis from an ongoing long-term extension (LTE) to the pivotal ATTR-ACT (Tafamidis in Transthyretin Cardiomyopathy Clinical Trial).. Patients with transthyretin amyloid cardiomyopathy who completed ATTR-ACT could enroll in an LTE, continuing with the same tafamidis dose or, if previously treated with placebo, randomized (2:1) to tafamidis meglumine 80 or 20 mg. All patients in the LTE transitioned to tafamidis free acid 61 mg (bioequivalent to tafamidis meglumine 80 mg) following a protocol amendment. In this interim analysis, all-cause mortality was assessed in patients treated with tafamidis meglumine 80 mg in ATTR-ACT continuing in the LTE, compared with those receiving placebo in ATTR-ACT transitioning to tafamidis in the LTE.. In the LTE, patients initially treated with tafamidis in ATTR-ACT had substantially better survival than those first treated with placebo, highlighting the importance of early diagnosis and treatment in transthyretin amyloid cardiomyopathy. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01994889 and NCT02791230.

Topics: Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Female; Heart Failure; Hospitalization; Humans; Male; Middle Aged; Prealbumin; Proportional Hazards Models; Time

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Liver Transplantation; Prealbumin; RNA, Small Interfering

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Myocardium; Prealbumin

Tafamidis has emerged as an effective treatment for patients with wild-type transthyretin cardiac amyloidosis (ATTRwt CA). The early experience of tafamidis treatment for Japanese patients with ATTRwt CA is reported here.Methods and Results: Over the past 2 years, in 82 patients with ATTRwt CA (mean age of 81.7±6.0 years), tafamidis treatment was initiated for 38 patients. The remaining 44 patients were not administered tafamidis. The most frequent reason for non-administration of tafamidis was advanced heart failure and the second most reason was the patient's frailty. In patients who received tafamidis treatment, there was no discontinuation of tafamidis due to adverse events, the rate of cardiovascular-related hospitalizations per year was 0.19, and the 1-year survival rate was 92%. In the patients who continued tafamidis for 12-18 months, there was no significant deterioration from baseline for high-sensitivity cardiac troponin T level, plasma B-type natriuretic peptide level, left ventricular ejection fraction, inter-ventricular septum wall thickness, or value of left ventricular longitudinal strain.. Tafamidis treatment was introduced for approximately half of the study patients with ATTRwt CA in real-world practice. Tafamidis is likely to be safe and may maintain the status of disease severity in the short-term in selected Japanese patients with ATTRwt CA. Further research is needed to determine appropriate patient selection for tafamidis treatment and efficacy of tafamidis in the long term.

Topics: Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Japan; Prealbumin; Stroke Volume; Ventricular Function, Left

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Heart Failure; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Heart Failure; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Heart Failure; Humans; Prealbumin; Prognosis

Transthyretin cardiomyopathy (ATTR-CM) is an under-recognized cause of heart failure, but it has received increasing attention due to the availability of treatment options. We present a case of hereditary transthyretin cardiomyopathy (A97S, an under-represented variant in current clinical studies) who presented with heart failure. Timely diagnosis and intervention with tafamidis demonstrated reversed cardiac remodelling via multiple imaging techniques (echocardiography, cardiac magnetic resonance imaging and technetium-99m pyrophosphate scintigraphy). The echocardiography and cardiac magnetic resonance imaging demonstrated improved global strain. Cardiac magnetic resonance imaging showed decreased extracellular volume. The technetium-99m pyrophosphate scintigraphy demonstrated decreased heart-to-contralateral ratio. This case highlights the potential reversible effect of tafamidis on A97S amyloidosis cardiomyopathy.

Topics: Amyloid Neuropathies, Familial; Cardiomyopathies; Diphosphates; Heart Failure; Humans; Prealbumin; Technetium; Ventricular Remodeling

Transthyretin amyloidosis (ATTR) variant is a life-threatening hereditary disease predominantly affecting the peripheral nervous system and heart. Tafamidis, which prevents the deposition of amyloid by stabilizing transthyretin, is available for the treatment of neuropathy and cardiomyopathy of ATTR. However, whether tafamidis could eliminate established amyloid deposits and improve cardiac function remains unknown. We reported a case of regression of left ventricular hypertrophy after tafamidis therapy in a patient with an ATTR variant. J. Med. Invest. 69 : 320-322, August, 2022.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Hypertrophy, Left Ventricular; Prealbumin

Dissociation of transthyretin (TTR) tetramers may lead to misfolding and aggregation of proamyloidogenic monomers, which underlies TTR amyloidosis (ATTR) pathophysiology. ATTR is a progressive disease resulting from the deposition of toxic fibrils in tissues that predominantly presents clinically as amyloid cardiomyopathy and peripheral polyneuropathy. Ligands that bind to and kinetically stabilize TTR tetramers prohibit their dissociation and may prevent ATTR onset. Drawing from clinically investigated AG10, we designed a constrained congener (

Topics: Amyloid Neuropathies, Familial; Animals; Dose-Response Relationship, Drug; Kinetics; Mice; Mice, Inbred BALB C; Mice, Knockout; Molecular Structure; Prealbumin; Retinol-Binding Proteins, Plasma; Structure-Activity Relationship

Transthyretin is a tetrameric protein which functions as a transporter of thyroxine and retinol-binding protein. Misfolding and amyloid aggregation of transthyretin are known to cause wild-type and hereditary transthyretin amyloidosis. Stabilization of the transthyretin tetramer by low molecular weight compounds is an efficacious strategy to inhibit the aggregation pathway in the amyloidosis. Here, we investigated the inhibitory activities of anthraquinone and xanthone derivatives against amyloid aggregation, and found that xanthone-2-carboxylic acid with one chlorine or methyl group has strong inhibitory activity comparable with that of diflunisal, which is one of the best known stabilizers of transthyretin. X-ray crystallographic structures of transthyretin in complex with the compounds revealed that the introduction of chlorine, which is buried in a hydrophobic region, is important for the strong inhibitory effect of the stabilizer against amyloidogenesis. An in vitro absorption, distribution, metabolism and elimination (ADME) study and in vivo pharmacokinetic study demonstrated that the compounds have drug-like features, suggesting that they have potential as therapeutic agents to stabilize transthyretin.

Topics: Amyloid Neuropathies, Familial; Anthraquinones; Crystallography, X-Ray; Dose-Response Relationship, Drug; Humans; Models, Molecular; Molecular Structure; Structure-Activity Relationship; Xanthones

Transthyretin (TTR) is a causative protein of TTR amyloidosis (ATTR amyloidosis), a general term for diseases characterized by deposition of TTR amyloid fibrils in specific organs. ATTR amyloidosis can be ameliorated by stabilization of the TTR tetramer through the binding of small molecules. Here, we show that the clinical anthelmintic drugs bithionol (

Topics: Amyloid Neuropathies, Familial; Anthelmintics; Bithionol; Crystallography, X-Ray; Drug Repositioning; Humans; Prealbumin; Thermodynamics; Triclabendazole

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathy, Restrictive; Compassionate Use Trials; Drug Approval; Drugs, Investigational; Heart Failure; Humans; Magnetic Resonance Imaging, Cine; Myocardial Perfusion Imaging; Treatment Outcome

Transthyretin (TTR) tetramer dissociation is rate limiting for aggregation and subunit exchange. Slowing of TTR tetramer dissociation

Topics: Amyloid; Amyloid Neuropathies, Familial; Benzoates; Benzoxazoles; Cardiomyopathies; Diflunisal; Humans; Kinetics; Prealbumin; Protein Aggregates; Protein Binding; Protein Multimerization; Protein Subunits; Pyrazoles; Tolcapone

Hereditary (ATTRv) and wild-type (ATTRwt) transthyretin amyloidosis are severe and fatal systemic diseases, characterised by amyloid fibrillar accumulation principally in the heart or peripheral nerves (or both). Since 2012, tafamidis has been used in France to treat patients with ATTRv with neuropathy (alone or combined with cardiomyopathy). Recently, the Phase III ATTR-ACT trial showed that tafamidis decreased the relative risk of mortality in ATTR amyloidosis with cardiomyopathy. The aims of this study were to assess the clinical characteristics of ATTR amyloidosis in a real-life population in comparison to the population included in the ATTR-ACT trial and to assess the impact of tafamidis treatment on major cardiovascular outcome (MCO)-free survival time without cardiac decompensation, heart transplant, or death.. From June 2008 to November 2018, 648 patients with ATTR amyloidosis (423 ATTRwt and 225 ATTRv) consecutively referred to the French Referral Center for cardiac amyloidosis were included. A total of 467 (72%) patients matched the inclusion criteria of the ATTR-ACT trial. For the 631 patients with cardiomyopathy, tafamidis treatment was associated with a longer median MCO-free survival time (n = 98): 1565 (1010-2400) days vs. 771 (686-895) days without treatment (log-rank P < 0.001). This association was confirmed after considering confounding factors (age at inclusion, N-terminal pro-B-type natriuretic peptide and amyloidosis type) with a propensity score (hazard ratio 0.546; P = 0.0132).. In a large cohort of ATTRwt and ATTRv patients, representative of the inclusion criteria of the ATTR-ACT trial, the present results show an association between tafamidis treatment and a lower occurrence of cardiovascular outcomes in a real-life population.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; France; Heart Failure; Humans

Since the first approval for transthyretin amyloid polyneuropathy patients, new formulations and different strength of tafamidis have been developed and tested in a different population (transthyretin amyloid cardiomyopathy). The objective of this analysis was to develop a unified population pharmacokinetic (PK) model of tafamidis, which can describe the PK of various different formulations in healthy subjects as well as patients with TTR amyloidosis, and to understand effects of intrinsic and extrinsic factors on the PK variability.. Pooled data from 23 clinical studies (17 Phase 1 and 6 Phase 2/3 studies) were used for the analysis. The plasma concentration-time data were analysed using a nonlinear mixed effects modelling methodology. Covariate analysis was performed using a stepwise covariate model building procedure.. The final model was a 2-compartment model with first-order absorption and elimination coupled with an absorption lag time for nonsolution formations. Body weight, food and tafamidis formulations were incorporated as structural covariates on PK parameters. Covariate analysis further identified age ≥65 years (14.5% decrease) and moderate hepatic impairment effects (57.6% increase) on apparent clearance and transthyretin amyloid polyneuropathy effect (17.3% decrease) on F. However, model-based clinical trial simulation results indicated that tafamidis steady-state exposure changes were not clinically meaningful under the tested conditions.. The unified population PK model of tafamidis was developed based on 23 studies. Subsequent clinical trial simulations indicated that no significant changes in tafamidis exposure necessitating a dose modification are expected due to either extrinsic or intrinsic factors. The model was used to support labelling statements for dose recommendations in special populations.

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Healthy Volunteers; Humans

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cost of Illness; Drug Costs; Health Care Costs; Hospitalization; Humans; Oligonucleotides; RNA, Small Interfering; Spain

ATTR-ACT (Tafamidis in Transthyretin Cardiomyopathy Clinical Trial) demonstrated the efficacy and safety of tafamidis in transthyretin amyloid cardiomyopathy (ATTR-CM). Model-based analyses from ATTR-ACT can examine predictor effects on dose-response/exposure-response relationships.. Parametric hazard distributions were developed for all-cause mortality and frequency of cardiovascular-related hospitalization. Time-to-event models were fitted to survival data, and repeated time-to-event models were fitted to hospitalization data. Disease-specific characteristics were assessed as baseline predictors of event hazards.. There were 441 patients in this analysis. At month 30, 70.5% (tafamidis) and 57.1% (placebo) of patients were alive, with 154/441 deaths reported; 495 cardiovascular-related hospitalizations occurred. The cumulative risk of death was 42.1% (95% confidence interval [CI] 24.2-58.0) lower with tafamidis than with placebo, regardless of New York Heart Association (NYHA) class; significant predictors of decreased risk were genotype (wild-type), greater 6-Minute Walk Test (6MWT) distance, higher left ventricular ejection fraction (LVEF), and lower blood urea nitrogen (BUN) and N-terminal pro-B-type natriuretic peptide concentrations. The average cumulative risk of cardiovascular-related hospitalization up to 30 months was 40.8% (95% CI 31.0-49.7) lower with tafamidis in NYHA class I/II patients. Significant predictors of reduced risk were greater 6MWT distance, higher LVEF, and lower BUN and troponin I concentrations.. Tafamidis reduced cumulative mortality and hospitalization risk versus placebo in patients with ATTR-CM. Baseline predictors of outcome were consistent with the cardiovascular nature of the disease and suggested that earlier treatment may improve outcomes. CLINICAL TRIALS.. NCT01994889 (date of registration: November 26, 2013).

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Hospitalization; Humans; Models, Statistical; Survival Analysis

氯苯唑酸是转甲状腺素蛋白稳定剂，用于治疗转甲状腺素蛋白淀粉样变多发性神经病以及转甲状腺素蛋白心脏淀粉样变（ATTR-CA）。该文对氯苯唑酸的作用机制及其治疗ATTR-CA的有效性、安全性的研究进行了较为全面的复习与分析，发现氯苯唑酸能够降低ATTR-CA患者全因死亡风险和住院率，且不良事件较少、较轻。提示氯苯唑酸治疗成人ATTR-CA安全、有效。.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Predictive Value of Tests; Prescriptions; Technetium Tc 99m Pyrophosphate

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cost-Benefit Analysis; Drug Approval; Health Policy; Humans; Randomized Controlled Trials as Topic; United States

Hereditary transthyretin amyloidosis is a rare progressive systemic disease. We describe a physically active 46-year-old man who presented with dyspnoea on exertion. An echocardiogram showed increased left ventricular wall thickness and diastolic dysfunction, but normal systolic function. The QRS voltage on ECG was normal. The patient was diagnosed with hypertrophic cardiomyopathy, and several years passed before establishment of the accurate diagnosis of hereditary transthyretin amyloidosis caused by the rare mutation ATTR Phe33Leu, previously described in only five case reports. Further investigation revealed neuropathy and nephropathy, and the patient developed severe heart failure. The patient is treated with tafamidis, has undergone heart transplantation and is currently planned for liver transplant. Hereditary transthyretin amyloidosis is likely underdiagnosed, especially in patients presenting with cardiomyopathy. A discrepancy between the left ventricular mass indicated by echocardiogram and that on ECG is an important indicator of amyloidosis, as is involvement of multiple organs.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Combined Modality Therapy; Diagnosis, Differential; Heart Transplantation; Humans; Leucine; Male; Middle Aged; Mutation; Phenylalanine; Prealbumin

In patients with transthyretin amyloid cardiomyopathy, tafamidis reduces all-cause mortality and cardiovascular hospitalizations and slows decline in quality of life compared with placebo. In May 2019, tafamidis received expedited approval from the US Food and Drug Administration as a breakthrough drug for a rare disease. However, at $225 000 per year, it is the most expensive cardiovascular drug ever launched in the United States, and its long-term cost-effectiveness and budget impact are uncertain. We therefore aimed to estimate the cost-effectiveness of tafamidis and its potential effect on US health care spending.. We developed a Markov model of patients with wild-type or variant transthyretin amyloid cardiomyopathy and heart failure (mean age, 74.5 years) using inputs from the ATTR-ACT trial (Transthyretin Amyloidosis Cardiomyopathy Clinical Trial), published literature, US Food and Drug Administration review documents, healthcare claims, and national survey data. We compared no disease-specific treatment ("usual care") with tafamidis therapy. The model reproduced 30-month survival, quality of life, and cardiovascular hospitalization rates observed in ATTR-ACT; future projections used a parametric survival model in the control arm, with constant hazards reduction in the tafamidis arm. We discounted future costs and quality-adjusted life-years by 3% annually and examined key parameter uncertainty using deterministic and probabilistic sensitivity analyses. The main outcomes were lifetime incremental cost-effectiveness ratio and annual budget impact, assessed from the US healthcare sector perspective. This study was independent of the ATTR-ACT trial sponsor.. Compared with usual care, tafamidis was projected to add 1.29 (95% uncertainty interval, 0.47-1.75) quality-adjusted life-years at an incremental cost of $1 135 000 (872 000-1 377 000), resulting in an incremental cost-effectiveness ratio of $880 000 (697 000-1 564 000) per quality-adjusted life-year gained. Assuming a threshold of $100 000 per quality-adjusted life-year gained and current drug price, tafamidis was cost-effective in 0% of 10 000 probabilistic simulations. A 92.6% price reduction from $225 000 to $16 563 would be necessary to make tafamidis cost-effective at $100 000/quality-adjusted life-year. Results were sensitive to assumptions related to long-term effectiveness of tafamidis. Treating all eligible patients with transthyretin amyloid cardiomyopathy in the United States with tafamidis (n=120 000) was estimated to increase annual healthcare spending by $32.3 billion.. Treatment with tafamidis is projected to produce substantial clinical benefit but would greatly exceed conventional cost-effectiveness thresholds at the current US list price. On the basis of recent US experience with high-cost cardiovascular medications, access to and uptake of this effective therapy may be limited unless there is a large reduction in drug costs.

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Cost-Benefit Analysis; Female; Humans; Male; Quality of Life

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans

Transthyretin amyloidosis (ATTR) is a threatening and severe genetic disease characterized by damages to organs and systems caused by a pathological protein transthyretin produced in the liver. Clinical manifestations of this disease vary from injuries of the nervous system to injuries of the cardiovascular system. Prognosis for ATTR-amyloidosis remains unfavorable. The absence of pathognomonic symptoms complicates diagnostics of this disease, which tends to simulate other conditions. At present, medicines exist, which are pathogenetic in the treatment of ATTR-amyloidosis. The article describes a clinical case of ATTR-amyloidosis with primary heart injury complicated with functional class III chronic heart failure during the tafamidis treatment.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Prealbumin

To test motor fiber excitability in early affected patients with transthyretin (TTR)-type familial amyloid polyneuropathy (TTR-FAP) before and during tafamidis treatment.. We examined the left median nerve of 21 healthy-matched controls and 10 early affected TTR-FAP patients using the automated threshold-tracking program, QTRAC. TTR-FAP patients were tested one day before the initiation of tafamidis treatment, 3 and 6 months later.. The drug was well-tolerated in all patients; there was no drop-out. No statistical difference was found between healthy controls and TTR-FAP patients at study entry. On treatment, both stimulus intensity for 50% of the maximal motor response and rheobase increased significantly from entry to the last evaluation at 6 months (P<0.05). Strength duration time constant decreased significantly from the 3rd to the 6th month of evaluation (P<0.05). There was also a "fanning-out" effect on the late depolarization phase (TEd 90-100ms) as well as a shortened relative refractory period from study entry to the 6th month of evaluation.. Threshold-tracking of median nerve motor fibers is not a helpful technique for the early diagnosis of TTR-FAP patients. Tafamidis was well-tolerated. We observed possible membrane hyperpolarization during treatment. Threshold tracking can contribute to documenting the action of new drugs to treat neuropathies. Tafamidis may change nerve electrical properties by reducing the burden of amyloid fibrils.

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Female; Humans; Male; Median Nerve; Nerve Fibers; Neural Conduction; Neuroprotective Agents; Treatment Outcome

An all-case, single-arm, observational, postmarketing surveillance is underway to assess the safety of tafamidis in patients with hereditary transthyretin (ATTRv) amyloidosis with peripheral polyneuropathy, also called transthyretin-type familial amyloid polyneuropathy, in Japan. Results from an interim analysis (data cutoff date, May 15, 2018) are presented in this preliminary report.. Patients were registered and treated with tafamidis meglumine 20 mg/d in routine clinical practice (observation period, 156 weeks). Data on patient demographic and clinical characteristics and adverse drug reactions (ADRs) were captured using case-report forms.. Of 219 patients included (mean age, 59.7 years; patients with age at disease onset ≥50 years, 61.2%; mean treatment duration, 95.5 weeks), 143 (65.3%) were male, 126 (57.5%) had a family history of ATTRv amyloidosis, and 149 (68.0%) originated from nonendemic areas. The most common ADRs were diarrhea (1.4%) and hematuria (0.9%). Six serious ADRs (pneumonia, bacteremia, malignant melanoma, pancreatic carcinoma, hematuria, and hereditary neuropathic amyloidosis [primary disease exacerbation]) were reported; no ADRs leading to death were recorded.. This interim analysis successfully provided comprehensive, nationwide epidemiologic data from 219 Japanese patients with ATTRv amyloidosis. The safety profile of tafamidis was largely consistent with that obtained from previous research. No new safety concerns were identified to date. Data presented in this interim analysis are subject to change following completion of the study, and we will continue to assess the safety and effectiveness of tafamidis throughout the study. ClinicalTrials.gov identifier: NCT02146378.

Topics: Adolescent; Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Female; Humans; Japan; Male; Middle Aged; Young Adult

Amyloid transthyretin (ATTR) amyloidosis is a widespread and fatal systemic amyloidosis characterized by the misfolding and amyloid aggregation of transthyretin (TTR). Studies suggest that dissociation of the TTR tetramer is the key step for its misfolding. Because of the importance of tetramer dissociation on ATTR amyloidosis, many TTR stabilizers have been discovered to stabilize the tetramer structure. This paper describes the application conventional molecular dynamics and metadynamics simulations to investigate the binding and unbinding mechanisms of two TTR stabilizers, including AG10 and tafamidis. AG10 has been granted an orphan drug designation by the U.S. Food and Drug Administration (FDA), and tafamidis was the first FDA-approved treatment for ATTR cardiomyopathy. The conventional molecular dynamics simulations reveal that both AG10 and tafamidis can stabilize the TTR tetramer through different mechanisms. AG10 stabilizes TTR tetramer by forming H-bonds with S117 to mimic the protective effect of T119M. Tafamidis stabilizes the tetramer by forming H-bond with S52 in the flexible CD loop to increase its structural stability. Despite the strong binding affinity of tafamidis, the free-energy surface constructed from metadynamics simulation suggests that tafamidis unbinds more readily than AG10 with lower free-energy barriers between the binding state and other intermediates. Finally, by performing pharmacophore analysis, we found two common important moieties of the studied compounds for their binding on the pockets, which can provide valuable guidance for future lead compounds' optimization in designing drugs for ATTR amyloidosis.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Molecular Dynamics Simulation; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Cost-Benefit Analysis; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Cost-Benefit Analysis; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Heart Diseases; Humans

Ala97Ser (A97S) is the major transthyretin (TTR) mutation in Taiwanese patients of familial amyloid polyneuropathy (FAP), characterized by a late-onset but rapidly deteriorated neuropathy. Tafamidis can restore the stability of some mutant TTR tetramers and slow down the progression of TTR-FAP. However, there is little understanding of the biophysical features of A97S-TTR mutant and the pharmacological modulation effect of tafamidis on it. This study aims to delineate the biophysical characteristics of A97S-TTR and the pharmacological modulation effect of tafamidis on this mutant.. The stability of TTR tetramers was assessed by urea denaturation and differential scanning calorimetry. Isothermal titration calorimetry (ITC) was used to measure the binding constant of tafamidis to TTR. Nuclear magnetic resonance spectroscopy (NMR) titration experiment was used to map out the tafamidis binding site.. Chemical and thermal denaturation confirmed the destabilization effect of A97S. Consistent with other the amyloidogenic mutant, A97S-TTR has slightly lower conformational stability. NMR revealed the binding site of A97S-TTR with tafamidis is at the thyroxine binding pocket. The ITC experiments documented the high affinity of the binding which can effectively stabilize the A97S-TTR tetramer.. This study confirmed the structural modulation effect of tafamidis on A97S-TTR and implied the potential therapeutic benefit of tafamidis for A97S TTR-FAP. This approach can be applied to investigate the modulation effect of tafamidis on other rare TTR variants and help to make individualized choices of available treatments for FAP patients.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Binding Sites; Biophysical Phenomena; Calorimetry; Humans; Magnetic Resonance Spectroscopy; Mutation; Prealbumin

Transthyretin amyloidosis (ATTR) is a rare, progressive, life-threatening, hereditary disorder caused by mutations in the transthyretin gene. Due to the phenotypic heterogeneity, ATTR is difficult to recognize and it is often diagnosed very late. In ATTR gastrointestinal (GI) disorders play an important role in the patients' morbidity and mortality. In some cases, GI symptoms are present even before the onset of the peripheral polyneuropathy. However, the complaints are various and it is really difficult to differentiate them from other GI disorders. We present a 61-year old male referred for diarrhea, unintentional weight loss and early satiety. He had hypotension after longstanding hypertension, numbness and tingling in the feet. We considered a broad differential diagnosis spectrum of chronic diarrhea syndrome and performed numerous laboratory, biochemical, imaging, endoscopic, histological and genetic tests. Transthyretin amyloidosis with a Glu89Gln mutation was diagnosed. Transthyretin amyloidosis is frequently misdiagnosed, representing a diagnostic challenge in GI practice. The presence of certain clinical combinations could help gastroenterologists to include ATTR in their diagnostic work-up.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Chronic Disease; Diagnosis, Differential; Diarrhea; DNA Mutational Analysis; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Mutation; Prealbumin; Predictive Value of Tests

Transthyretin cardiac amyloidosis is a progressive and life-threating disease that is significantly underdiagnosed, and the actual number of patients with the disease is presently unknown. Accumulation of wild-type transthyretin-derived amyloid in the heart is a common finding in very elderly patients. Recent clinical trials demonstrated that tafamidis reduced all-cause death and the number of cardiovascular hospitalizations when compared with placebo. The Japanese Ministry of Health, Labour and Welfare approved tafamidis (Vyndaqel

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Prealbumin

Plasma protein transthyretin (TTR) can undergo conformational change resulting in the formation of amyloid fibrils that can then cause amyloidosis. This can occur spontaneously in individuals over the age of 70-80 resulting in wild-type transthyretin amyloidosis (ATTR) (with cardiomyopathy). This then progresses to fatal cardiac failure. TTR can also undergo conformational change in individuals who have a genetic abnormality in the structure of TTR resulting in hereditary ATTR amyloidosis. This is usually first manifested as polyneuropathy but can progress to cardiomyopathy with time. Until recently, there has been no specific treatment for these conditions. However, a detailed search for compounds that stabilize TTR resulted in the discovery of tafamidis. This compound stabilizes TTR and has been found to significantly reduce the progression of both wild-type ATTR amyloidosis and hereditary ATTR amyloidosis.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Prealbumin

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Heart; Humans; Magnetic Resonance Angiography; Male; Treatment Outcome

Tafamidis meglumine, a transthyretin (TTR) stabilizer, is effective in delaying the progression of neuropathy in TTR amyloidosis with Val30Met mutations. However, its efficacy in TTR amyloid cardiomyopathy is not fully elucidated. Herein, we report a 73-year-old Japanese man with a diagnosis of TTR amyloid cardiomyopathy with Val30Met mutation treated with tafamidis. To evaluate treatment response, cardiac magnetic resonance imaging was performed before and after 12 months of tafamidis treatment. Native T1, extracellular volume, and left ventricular mass showed no obvious worsening, and findings of other diagnostic studies also supported the efficacy of tafamidis to delay the progression of amyloid cardiomyopathy. Our case suggests that serial native T1 and extracellular volume may be novel non-invasive imaging methods to monitor the treatment response to TTR stabilizers in cardiac amyloidosis and also that tafamidis may be effective in suppressing cardiac progression in TTR amyloid cardiomyopathy with Val30Met mutation.

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Biopsy; Cardiomyopathies; Electrocardiography; Follow-Up Studies; Humans; Magnetic Resonance Imaging, Cine; Male; Myocardium

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Humans; Prealbumin

Ocular abnormalities have been known to occur in hereditary amyloidotic polyneuropathy since the 1950s. While vitreous opacities and scalloped pupils were described early it has become evident that every component of the eye from the conjunctiva to the retinal vasculature can be involved. Reports from the major centres in Japan, Portugal and Sweden, which primarily treat patients with ATTRV30M, have indicated that with the increased longevity seen in patients treated with liver transplantation the frequency of the more severe eye findings, notably vitreous opacities and subsequent glaucoma, are being detected more frequently.. In an attempt to confirm that the experience was similar in a broader range of locales we performed a survey of ten treatment centres in eight countries to determine the frequency of severe ocular abnormalities (vitreous opacities and glaucoma) in 804 patients with V30M disease and whether there was any relationship to treatment with liver transplantation or the transthyretin stabilizer tafamidis.. The data indicate that the frequency of these abnormalities increases with increasing duration of disease. In patients broadly matched for duration of disease the frequency was higher in subjects who had undergone liver transplantation than in those who were untreated.. Retrospective surveys are subject to a number of potential biases. In this case, the major potential confounders were defining the time of disease onset and physician bias in choice of therapy, particularly regarding the choice of patients and the time in their course when they should undergo liver transplantation, and when and whether they should receive tafamidis. Nonetheless it appears that the incidence of severe ocular abnormalities in V30M subjects from centres around the world is similar to those found in centres in the areas endemic for this variant protein. The incidence increased with duration of disease regardless of therapy with the highest frequencies seen in patients more than ten years after diagnosis who had undergone liver transplantation.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Eye Diseases; Humans; Mutation, Missense; Prealbumin; Protein Aggregation, Pathological

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Male; Middle Aged; Mutation, Missense; Prealbumin; Proteinuria; Treatment Outcome

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Polyneuropathies; Prealbumin; RNA, Small Interfering

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Polyneuropathies; Prealbumin; RNA, Small Interfering

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Multicenter Studies as Topic; Randomized Controlled Trials as Topic

BACKGROUNDThe hereditary transthyretin (TTR) amyloidoses are a group of diseases for which several disease-modifying treatments are now available. Long-term effectiveness of these therapies is not yet fully known. Moreover, the existence of alternative therapies has resulted in an urgent need to identify patient characteristics that predict response to each therapy.METHODSWe carried out a retrospective cohort study of 210 patients with hereditary TTR amyloidosis treated with the kinetic stabilizer tafamidis (20 mg qd). These patients were followed for a period of 18-66 months, after which they were classified by an expert as responders, partial responders, or nonresponders. Correlations between baseline demographic and clinical characteristics, as well as plasma biomarkers and response to therapy, were investigated.RESULTS34% of patients exhibited an almost complete arrest of disease progression (classified by an expert as responders); 36% had a partial to complete arrest in progression of some but not all disease components (partial responders); whereas the remaining 30% continued progressing despite therapy (nonresponders). We determined that disease severity, sex, and native TTR concentration at the outset of treatment were the most relevant predictors of response to tafamidis. Plasma tafamidis concentration after 12 months of therapy was also a predictor of response for male patients. Using these variables, we built a model to predict responsiveness to tafamidis.CONCLUSIONOur study indicates long-term effectiveness for tafamidis, a kinetic stabilizer approved for the treatment of hereditary TTR amyloidosis. Moreover, we created a predictive model that can be potentially used in the clinical setting to inform patients and clinicians in their therapeutic decisions.

Topics: Adult; Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Biomarkers; Cohort Studies; Demography; Female; Humans; Longitudinal Studies; Male; Middle Aged; Models, Biological; Prealbumin; Sex Factors; Treatment Outcome; Young Adult

Topics: Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Angiotensin-Converting Enzyme Inhibitors; Benzoxazoles; Cardiomyopathies; Cardiovascular Agents; Clinical Trials as Topic; Diuretics; Female; Humans; Male; Rare Diseases

Transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) is a fatal disease with no available disease-modifying therapies. While pathogenic TTR mutations (TTRm) destabilize TTR tetramers, the T119M variant stabilizes TTRm and prevents disease. A comparison of potency for leading TTR stabilizers in clinic and structural features important for effective TTR stabilization is lacking. Here, we found that molecular interactions reflected in better binding enthalpy may be critical for development of TTR stabilizers with improved potency and selectivity. Our studies provide mechanistic insights into the unique binding mode of the TTR stabilizer, AG10, which could be attributed to mimicking the stabilizing T119M variant. Because of the lack of animal models for ATTR-CM, we developed an in vivo system in dogs which proved appropriate for assessing the pharmacokinetics-pharmacodynamics profile of TTR stabilizers. In addition to stabilizing TTR, we hypothesize that optimizing the binding enthalpy could have implications for designing therapeutic agents for other amyloid diseases.

Topics: Administration, Oral; Amyloid Neuropathies, Familial; Animals; Benzoates; Biomimetics; Dogs; Entropy; Female; Humans; Male; Models, Molecular; Mutation; Prealbumin; Protein Conformation; Protein Stability; Pyrazoles; Serum Albumin, Human; Thermodynamics

Topics: Amyloid Neuropathies, Familial; Animals; Benzoxazoles; Brain; Caco-2 Cells; Humans; Liver; Male; Microsomes, Liver; Organ Specificity; Rats; Rats, Sprague-Dawley

Background This retrospective longitudinal study was performed to determine whether tafamidis treatment leads to improvements in commonly used blood data for transthyretin familial amyloid polyneuropathy (TTR-FAP). Methods Commonly used blood data (complete blood count [including a haemogram], total protein, albumin, blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, γ-glutamyl transpeptidase, total bilirubin [T-Bil], creatine kinase, choline esterase, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, estimated glomerular filtration rate [eGFR], serum amyloid A protein, TTR, haemoglobin A1c, free triiodothyronine [FT3] and free thyroxine [FT4]) were investigated in 33 TTR-FAP patients. These values included longitudinal data at three time points: six months before or after tafamidis treatment and one year after tafamidis treatment. Longitudinal changes in each blood item were examined using a linear mixed model, adjusting for age at starting tafamidis, sex, TTR-FAP stage and value before tafamidis treatment. Results Our results show elevated TTR concentrations after tafamidis treatment. In contrast, haemoglobin, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, mean platelet volume, platelet distribution width, T-Bil, eGFR, FT3 and FT4, gradually decreased through a reference range. There were no characteristic observations in any other items. TTR binds to thyroid hormone; therefore, FT3 and FT4 decreased in inverse proportion to increased TTR concentrations. Conclusion Unfortunately, progression to anaemia may occur regardless of tafamidis treatment. Because anaemia is sometimes present in TTR-FAP, attention should be paid to longitudinal changes in commonly used blood data, irrespective of tafamidis treatment.

Topics: Amyloid Neuropathies, Familial; Anemia; Benzoxazoles; Blood Chemical Analysis; Disease Progression; Female; Humans; Longitudinal Studies; Male; Middle Aged; Retrospective Studies

Oculomeningovascular amyloidosis is a variant of transthyretin (TTR) amyloidotic polyneuropathy, which is associated with blindness and brain ischemia, microhemorrages, and siderosis due to prominent production of the abnormal TTR in the eye and in the choroid plexuses. Tafamidis is a TTR stabilizer that is orally administered and, by interfering with amyloid fibril formation and deposition, is capable of slowing progression of TTR polyneuropathy and of early-stage cardiomyopathy. However, the ocular manifestations of amyloid deposition progressed despite tafamidis therapy in Val30Met TTR amyloidosis, and the effects of tafamidis on meningovascular amyloidosis are unknown. We observed failure of tafamidis to halt progression of oculomeningovascular amyloid deposition in a patient with familial Ala36Pro TTR amyloidosis. She received molecular diagnosis at age 24 and presented at age 26 with paresthesias of the lower limbs and bowel dysfunction. Echography showed minimal amyloid opacities in the corpus vitreum. Treatment with tafamidis meglumine was started. Sixteen months later, she complained of severe headache followed by left hemiparesthesias and numbness lasting 20 minutes. Magnetic resonance imaging showed multiple focal and diffuse hemosiderin deposits compatible with microbleeds and early siderosis. Echography showed a marked increase of "vitreal opacities." Our observation confirms that tafamidis fails in halting increase of vitreal amyloid deposits and indicates that it is presumably ineffective in preventing clinical onset due to progression of meningovascular amyloidosis. These failures may be due to the incapability of tafamidis to cross the blood-retina and blood-brain barriers. Therapeutic options targeting oculomeningovascular TTR amyloidoses in humans are required.

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Blindness; Brain Ischemia; Cerebrovascular Disorders; Disease Progression; Eye Diseases; Female; Genetic Predisposition to Disease; Humans; Intracranial Hemorrhages; Magnetic Resonance Imaging; Mutation; Phenotype; Prealbumin; Siderosis; Treatment Failure; Ultrasonography

Hereditary amyloidosis related to transthyretin V30M (hATTR V30M) is a progressive length-dependent sensorimotor axonal neuropathy. We aimed to compare the disease progression of treated [liver transplantation (LT) or tafamidis] versus untreated patients with hATTR V30M.. A total of 81 patients with hATTR V30M were included: 27 untreated, 25 treated with LT and 29 undergoing tafamidis treatment. Neuropathy was assessed at baseline, 12, 24 and 36 months after study entry. We evaluated disease stage, modified polyneuropathy disability (mPND) score and a composite neurophysiological score comprised of sensory and motor conduction parameters. The effect of treatment on disease progression was analysed using linear mixed-effects modelling.. At baseline, patients from the untreated group were older (P < 0.01) and those in the LT group had longer disease duration than those in the tafamidis group (P < 0.05). Gender, mPND and motor scores at study entry were equal in the three groups; however, the untreated group had lower sensory scores compared with the tafamidis group (P < 0.01). During the 3-year follow-up period, progression to stage II of the disease was seen only in the untreated group. The progression on mPND, sensory and motor scores was significantly higher in the untreated patients. When treated groups were compared, the LT group had lower rates of composite neurophysiological score progression. However, the sensory score outcome was similar between tafamidis responders and LT patients.. Both LT and tafamidis therapy modified the natural history of hATTR V30M by reducing neuropathy progression.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Female; Humans; Liver Transplantation; Male; Middle Aged; Neural Conduction; Polyneuropathies; Time Factors; Treatment Outcome

Hereditary transthyretin (TTR) amyloidosis associated with the TTRV30M (p.TTRV50M) mutation presents predominantly as an axonal polyneuropathy, with variable involvement of other organs. Serious central nervous system (CNS) and eye manifestations, including stroke, dementia, vitreous opacities and glaucoma, have been reported in untreated V30M TTR amyloidosis patients, and in these patients after treatment with liver transplantation (LT). Distinct therapies for V30M TTR amyloidosis developed during the last decade exhibit promising results in slowing the peripheral and autonomic nervous system pathology. However, the effect of these therapies on the CNS and eye manifestations of V30M TTR amyloidosis is not known. Herein, we show that in a small cohort of patients taking tafamidis orally (20 mg tafamidis meglumine daily) we could detect this small molecule in the cerebrospinal fluid (CSF) and the vitreous body. In the CSF, the ratio of TTR tetramer to tafamidis was ≈2:1, leading to a moderate kinetic stabilization of TTR in the CSF of these patients. Our data suggest that tafamidis can cross the CSF-blood and eye-blood barriers. Future studies comparing CNS and eye manifestations in patients treated with LT, kinetic stabilizers or TTR lowering drugs are essential to understand the clinical effect of our observations.

Topics: Administration, Oral; Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Cerebrospinal Fluid; Chromatography, High Pressure Liquid; Female; Humans; Liver Transplantation; Male; Mutation; Prealbumin; Vitreous Body

Transthyretin is a transport protein for thyroxine and retinol-binding protein, which is mainly produced in the liver. Hereditary transthyretin-related amyloidosis (ATTR) is caused by one of more than 120 point mutations in the transthyretin gene and inherited as an autosomal dominant disorder. The mutations cause a reduction in the stability of the tetrameric structure and dissociation into dimers and monomers as the rate-limiting step in amyloid formation is promoted. Clinical symptoms are related to the specific mutation, the age of onset, the ethnic background and environmental factors. The nerves, heart, eyes and intestines are paticularly affected. In general, two different age peaks are observed. An accumulation occurs at the age of 25-35 years with predominantly neurological symptoms. The second peak occurs between the ages of 55 and 65 years and is commonly associated with cardiac involvement with or without polyneuropathy. Characteristic for the nerve involvement are the symmetrical small fiber polyneuropathy and an autonomous polyneuropathy. The typical picture of cardiac involvement is biventricular hypertrophy with diastolic dysfunction finally resulting in restrictive cardiomyopathy. In addition to the symptomatic treatment for the alleviation of individual organ disorders, for many years liver transplantation was the only causal therapy of ATTR amyloidosis. Since 2011 tafamidis, a highly selective transthyretin stabilizer, has been the first drug approved for treatment of ATTR resulting in reduction of the progression of polyneuropathic symptoms. Other therapeutic approaches to reduce amyloid formation (patisiran and inotersen) effectively reduce transthyretin blood levels, leading to a reduction in polyneuropathy and improved quality of life. The approval is expected in 2018.

Topics: Aged; Amyloid; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Drug Approval; Humans; Middle Aged; Mutation; Polyneuropathies; Prealbumin; Quality of Life

To assess the natural history and treatment effect on survival among patients with transthyretin-associated familial amyloid polyneuropathy (TTR-FAP) stage 1 Val30Met.. Multi-institutional, hospital-based study of patients with TTR-FAP Val30Met prospectively followed up until December 2016, grouped into untreated (n = 1,771), liver transplant (LTx)-treated (n = 957), or tafamidis-treated (n = 432) cohorts. Standardized mortality ratios, Kaplan-Meier, and Cox methods were used to estimate excess mortality, survival, and adjusted hazard ratios (HRs) for all-cause mortality.. Disease-modifying treatments decreased TTR-FAP excess mortality from 10 to 4 (standardized mortality ratio 3.92, 95% confidence interval [CI] 2.64-5.59). Median overall survival of untreated and LTx-treated cohorts was 11.61 (95% CI 11.14-11.87) and 24.73 years (95% CI 22.90-27.09), respectively, and was not reached in the tafamidis-treated cohort (maximum follow-up, 10 years). Both disease-modifying treatments improved survival. Among early-onset patients (younger than 50 years of age), tafamidis reduced the mortality risk compared with untreated patients by 91% (HR 0.09, 95% CI 0.03-0.25,. LTx and tafamidis convey substantial survival benefits, but TTR-FAP mortality remains higher than in the general population. These results strongly reinforce the importance of timely diagnosis and earlier treatment, boosting the pursuit for an increased life expectancy.. This study provides Class III evidence that for patients with stage 1 Val30Met TTR-FAP, LTx and tafamidis increase survival.

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Female; Follow-Up Studies; Humans; Liver Transplantation; Male; Middle Aged

Transthyretin familial amyloid polyneuropathy is an autosomal dominant inherited sensorimotor and autonomic polyneuropathy, which if untreated, leads to death in approximately 10 years. In Brazil, liver transplant and tafamidis are the only disease-modifying treatments available. This review consists of a consensus for the diagnosis, management and treatment for transthyretin familial amyloid polyneuropathy from the Peripheral Neuropathy Scientific Department of the Brazilian Academy of Neurology. The first and last authors produced a draft summarizing the main views on the subject and emailed the text to 10 other specialists. Relevant literature on this subject was reviewed by each participant and used for the individual review of the whole text. Each participant was expected to review the text and send a feedback review by e-mail. Thereafter, the 12 panelists got together at the city of Fortaleza, discussed the controversial points, and reached a consensus for the final text.

Topics: Amyloid Neuropathies, Familial; Animals; Benzoxazoles; Brazil; Cardiomyopathies; Diagnosis, Differential; Humans; Oligonucleotides; Randomized Controlled Trials as Topic; RNA, Small Interfering

Transthyretin amyloidosis is a systemic disorder caused by extracellular deposition of insoluble amyloid fibrils in peripheral and autonomic nerves, heart, kidney, gastrointestinal tract, and other organs. Hereditary transthyretin amyloidosis is an autosomal dominant disease. More than 120 mutations have been reported in the transthyretin gene with considerable phenotypic heterogeneity and geographic diversity. Among them, a sporadic case of hereditary transthyretin amyloidosis with cardiac-predominant phenotype is very rare, progressive, and potentially fatal if left undiagnosed. However, a clinical diagnosis of cardiac amyloidosis still remains challenging due to non-specific symptoms, and less sensitivity and specificity of medical examinations.. A 60-year-old Japanese man with a history of embolic stroke and hypertrophic cardiomyopathy visited our department for heart failure. The present case exhibited only cardiomyopathy without any clinical signs of systemic amyloidosis manifested as carpal tunnel syndrome, polyneuropathy, or autonomic dysfunction. An echocardiogram revealed severe asymmetric left ventricular hypertrophy, biatrial dilatation, pericardial effusion, and preserved left ventricular ejection fraction of 50% with severe diastolic dysfunction. Technetium pyrophosphate scintigraphy indicated marked diffuse myocardial uptake of technetium pyrophosphate, strongly suggesting transthyretin cardiac amyloidosis, which was firmly confirmed by a left ventricular endomyocardial biopsy. Genetic analysis demonstrated a transthyretin C70T (Pro24Ser) heterozygous mutation. Tafamidis, a transthyretin stabilizer, was started. His cardiac symptoms remained unchanged for 12 months.. Here we report the case of a patient with hereditary cardiac amyloidosis associated with a Pro24Ser mutation in transthyretin, which is the first case reported in Japan. Technetium pyrophosphate scintigraphy was extremely useful for definitive diagnosis. Thus, we propose that the nuclear imaging technique should be taken into account even for an exploratory diagnosis of transthyretin cardiac amyloidosis.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Diuretics; Echocardiography; Genes, Dominant; Humans; Male; Middle Aged; Mutation; Prealbumin; Radionuclide Imaging; Treatment Outcome

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Case-Control Studies; Electrochemical Techniques; Female; Follow-Up Studies; Galvanic Skin Response; Humans; Male; Middle Aged; Mutation; Neural Conduction; Prealbumin; Prognosis; Prospective Studies

Rate-limiting dissociation of the tetrameric protein transthyretin (TTR), followed by monomer misfolding and misassembly, appears to cause degenerative diseases in humans known as the transthyretin amyloidoses, based on human genetic, biochemical and pharmacologic evidence. Small molecules that bind to the generally unoccupied thyroxine binding pockets in the native TTR tetramer kinetically stabilize the tetramer, slowing subunit dissociation proportional to the extent that the molecules stabilize the native state over the dissociative transition state-thereby inhibiting amyloidogenesis. Herein, we use previously reported structure-activity relationship data to develop two semi-quantitative algorithms for identifying the structures of potent and selective transthyretin kinetic stabilizers/amyloidogenesis inhibitors. The viability of these prediction algorithms, in particular the more robust in silico docking model, is perhaps best validated by the clinical success of tafamidis, the first-in-class drug approved in Europe, Japan, South America, and elsewhere for treating transthyretin aggregation-associated familial amyloid polyneuropathy. Tafamidis is also being evaluated in a fully-enrolled placebo-controlled clinical trial for its efficacy against TTR cardiomyopathy. These prediction algorithms will be useful for identifying second generation TTR kinetic stabilizers, should these be needed to ameliorate the central nervous system or ophthalmologic pathology caused by TTR aggregation in organs not accessed by oral tafamidis administration.

Topics: Amyloid Neuropathies, Familial; Computer Simulation; Drug Design; Humans; Molecular Docking Simulation; Prealbumin; Protein Multimerization; Protein Stability; Small Molecule Libraries

Genetic inherited conditions may result in feelings of stigmatisation, mainly because of visible physical appearance and its transmissibility to offspring.. This article reports accounts of stigmatisation from Portuguese patients affected by the inherited neurodegenerative disease, familial amyloid polyneuropathy (FAP), living in the largest cluster of patients worldwide.. We draw on semi-structured interviews conducted with individuals at-risk or affected by FAP, recruited through the national patients' association, about their experiences of stigmatisation related to the illness.. Findings highlight the influence of a discrediting social context in the enactment of stigma. FAP was described as a source of devaluation and social distance and was permeated by beliefs of contagion in the community, especially in the past. The multigenerational nature of the illness within small communities was felt as a source of rejection for courtship and of devalued reproductive worth. Decisions to have (potentially affected) children seemed to be a target of implicit negative judgment. Dealing with stigma entailed restraint in talking about FAP especially outside the family, resistance to being treated as different, and social withdrawal. Some participants referred to recent substantial improvements in their social acceptance and a reduction in the intensity of the stigmatisation to which they are subject.. The pattern of stigma may have changed considerably within the past few decades, as medical information about the disease became more widespread, as new medications have been introduced and as clinical trials of other potential treatments have been established. Our findings report the social consequences of stigma towards this disease group and may help to understand how stigma is experienced in other heritable diseases.

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Female; Genetic Diseases, Inborn; Humans; Male; Middle Aged; Portugal; Qualitative Research; Reproductive Behavior; Social Stigma; Surveys and Questionnaires

Topics: Adult; Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Cell Survival; Female; Humans; Male; Middle Aged; Mutation; Plasma

A 54-year-old man with polycystic liver disease received a domino liver transplantation (DLT) from a patient of hereditary ATTR amyloidosis with the transthyretin Ser50Arg mutation. Ten years after transplantation, he felt a slight numbness in his toes, and cardiac amyloidosis was simultaneously suspected upon a heart function evaluation. Biopsy specimens from the myocardium revealed transthyretin amyloidosis with the Ser50Arg mutation. Oral tafamidis therapy has inhibited the progression of neurological and cardiovascular symptoms this far. We herein report this first case of amyloid polyneuropathy and myocardial amyloidosis after DLT from hereditary ATTR amyloidosis with a transthyretin Ser50Arg mutation and discuss similar cases of other mutations.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Cysts; Humans; Liver Diseases; Liver Transplantation; Male; Middle Aged; Mutation; Prealbumin; Treatment Outcome

Tafamidis is a transthyretin (TTR) stabilizer recently approved to slow the neurologic impairment in TTR familial amyloid polyneuropathy (TTR-FAP). The pivotal studies on Tafamidis reported encouraging results on the short term, in the early onset Val30Met-TTR-FAP patients at an early stage of the neuropathy. However, the effect of the drug in the non-Val30Met patients, at a more advanced stage of the disease and on the long term, is less known. In this study, we report the effect of Tafamidis in 43 TTR-FAP patients with a variety of pathogenic mutations, including 53% of non-Val30Met variants, at different stages of neuropathy followed on the long term. General and neurological assessment was performed in a standardized protocol every 6-12 months along with neurophysiological variables, including testing of small nerve fibres. The mean follow-up under treatment was 2 years with a subset of 26 patients treated for 3 years. Overall, Tafamidis was well tolerated. A significant clinical deterioration of the neuropathy and the patient's general condition was observed across the 3 years follow-up, although neurophysiological parameters remained stable for the first 2 years. In contrast, patients had a significant increase of BMI under treatment. Deterioration of the neuropathy correlated to an older age at disease onset or treatment initiation and to poor clinical status at baseline. A higher BMI at baseline was associated with a lower progression of the neuropathy. About one-third of the patients who received 3 years of tafamidis had still preserved walking capacity or good clinical condition, suggesting that tafamidis slowed the disease progression in some patients. Overall, our work shows that tafamidis is well tolerated in TTR-FAP but does not prevent the steady progression of the neuropathy on the long term. Age, neurologic status, and general condition at baseline appear to be best predictors of tafamidis efficacy on the neurological function.

Topics: Adult; Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Body Mass Index; Disease Progression; Female; Follow-Up Studies; Hematologic Agents; Humans; Male; Middle Aged; Neural Conduction; Time Factors; Treatment Outcome

Familial amyloid polyneuropathy (FAP) is a rare hereditary disorder caused by mutations in the transthyretin (TTR) gene. Tafamidis is a TTR stabilizer able to prevent TTR tetramer dissociation, and several studies have demonstrated its safety and efficacy at slowing the progression of neuropathy in FAP caused by the TTR Val30Met mutation. However, nerve conduction study (NCS) and electromyography (EMG) results have yet to be reported in relation to FAP progression during tafamidis therapy.. A 71-year-old man was admitted to the hospital because of severe numbness and walking difficulties. He did not complain of any autonomic dysfunction or visual disturbance, and he had no family history of neuromuscular disorders. A NCS and EMG indicated length-dependent axonal sensorimotor polyneuropathy. A sural nerve biopsy revealed amyloid deposits, and genetic testing demonstrated a TTR Val30Met mutation. We diagnosed the patient with FAP and treated him using tafamidis therapy. One year later, the patient is still on tafamidis therapy, and his symptoms have shown no significant change. The NCS showed no changes in the compound muscle action potential amplitudes of the left ulnar nerve, while EMG showed the fibrillation/positive sharp wave to have disappeared from the patient's upper limb. We conclude from these findings a slowing of the neurologic progression.. Tafamidis was effective in slowing the neurologic progression over one year in a FAP patient with the TTR Val30Met mutation, and NCS and EMG were useful for assessing this therapeutic effect.

Topics: Aged; Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Male

Tafamidis is a transthyretin (TTR) stabilizer able to prevent TTR tetramer dissociation. There have been a few encouraging studies on Tafamidis efficacy in early-onset inherited transthyretin amyloidosis (ATTR) due to Val30Met mutation. However, less is known about its efficacy in later disease stages and in non-Val30Met mutations. We performed a multi-center observational study on symptomatic ATTR patients prescribed to receive Tafamidis. We followed up patients according to a standardized protocol including general medical, cardiological and neurological assessments at baseline and every 6 months up to 3 years. Sixty-one (42 males) patients were recruited. Only 28 % of enrolled subjects had the common Val30Met mutation, mean age of onset was remarkably late (59 years) and 18 % was in advanced disease stage at study entry. Tafamidis proved safe and well-tolerated. One-third of patients did not show significant progression along 36 months, independently from mutation type and disease stage. Neurological function worsened particularly in the first 6 months but progression slowed significantly thereafter. Autonomic function remained stable in 33 %, worsened in 56 % and improved in 10 %. Fifteen percent of patients showed cardiac disease progression and 30 % new onset of cardiomyopathy. Overall, Tafamidis was not able to prevent functional progression of the disease in 23 (43 %) subjects, including 16 patients who worsened in their walking ability and 12 patients who reached a higher NYHA score during the follow-up period. A higher mBMI at baseline was associated with better preservation of neurological function. In conclusion, neuropathy and cardiomyopathy progressed in a significant proportion of patients despite treatment. However, worsening of neurological function slowed after the first 6 months and also subjects with more advanced neuropathy, as well as patients with non-Val30Met mutation, benefited from treatment. Body weight preservation is an important favorable prognostic factor.

Topics: Adult; Aged; Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Female; Follow-Up Studies; Humans; Italy; Longitudinal Studies; Male; Middle Aged; Mutation; Prealbumin; Prognosis; Severity of Illness Index; Treatment Outcome

ATTR amyloidosis is a systemic, debilitating and fatal disease caused by transthyretin (TTR) amyloid accumulation. RNA interference (RNAi) is a clinically validated technology that may be a promising approach to the treatment of ATTR amyloidosis. The vast majority of TTR, the soluble precursor of TTR amyloid, is expressed and synthesized in the liver. RNAi technology enables robust hepatic gene silencing, the goal of which would be to reduce systemic levels of TTR and mitigate many of the clinical manifestations of ATTR that arise from hepatic TTR expression. To test this hypothesis, TTR-targeting siRNAs were evaluated in a murine model of hereditary ATTR amyloidosis. RNAi-mediated silencing of hepatic TTR expression inhibited TTR deposition and facilitated regression of existing TTR deposits in pathologically relevant tissues. Further, the extent of deposit regression correlated with the level of RNAi-mediated knockdown. In comparison to the TTR stabilizer, tafamidis, RNAi-mediated TTR knockdown led to greater regression of TTR deposits across a broader range of affected tissues. Together, the data presented herein support the therapeutic hypothesis behind TTR lowering and highlight the potential of RNAi in the treatment of patients afflicted with ATTR amyloidosis.

Topics: Amyloid Neuropathies, Familial; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzoxazoles; Disease Models, Animal; Drug Evaluation, Preclinical; Female; Gene Expression; Humans; Liver; Macaca fascicularis; Male; Mice; Mice, Transgenic; Prealbumin; RNA Interference; RNA, Messenger; RNA, Small Interfering

Transthyretin-related familial amyloid polyneuropathy (TTR-FAP) is a hereditary disease with variable geographical distribution. The aim of this study was to present our experience with TTR-FAP patients. We retrospectively analyzed nine cases belonging to different families. Diagnostic criteria were based on the combination of compatible clinical picture, histopathological findings and genetic confirmation. Five cases showed the classic presentation and other 4 the late onset variant. The p.Val30Met mutation in the TTR gene was found in 6 cases and p.Ala36Pro, p.Thr60Ala and p.Tyr114Cys in the remaining 3, respectively. The median age of symptom onset was 35 years (26-60 range). Mean time to diagnosis was 4.2 ± 1.5 years. Our patient series showed the heterogeneity in clinical presentation of TTR-FAP in a non-endemic region of South America.

Topics: Adult; Amyloid Neuropathies, Familial; Argentina; Benzoxazoles; Fatal Outcome; Female; Humans; Liver Transplantation; Male; Middle Aged; Mutation; Prealbumin; Retrospective Studies

Early diagnosis of familial transthyretin (TTR) amyloid diseases remains challenging because of variable disease penetrance. Currently, patients must have an amyloid positive tissue biopsy to be eligible for disease-modifying therapies. Endomyocardial biopsies are typically amyloid positive when cardiomyopathy is suspected, but this disease manifestation is generally diagnosed late. Early diagnosis is often difficult because patients exhibit apparent symptoms of polyneuropathy, but have a negative amyloid biopsy. Thus, there is a pressing need for an additional early diagnostic strategy for TTR-aggregation-associated polyneuropathy and cardiomyopathy.. Global peripheral blood cell mRNA expression profiles from 263 tafamidis-treated and untreated V30M Familiar Amyloid Neuropathy patients, asymptomatic V30M carriers, and healthy, age- and sex-matched controls without TTR mutations were used to differentiate symptomatic from asymptomatic patients. We demonstrate that blood cell gene expression patterns reveal sex-independent, as well as male- and female-specific inflammatory signatures in symptomatic FAP patients, but not in asymptomatic carriers. These signatures differentiated symptomatic patients from asymptomatic V30M carriers with >80% accuracy. There was a global downregulation of the eIF2 pathway and its associated genes in all symptomatic FAP patients. We also demonstrated that the molecular scores based on these signatures significantly trended toward normalized values in an independent cohort of 46 FAP patients after only 3 months of tafamidis treatment.. This study identifies novel molecular signatures that differentiate symptomatic FAP patients from asymptomatic V30M carriers as well as affected males and females. We envision using this approach, initially in parallel with amyloid biopsies, to identify individuals who are asymptomatic gene carriers that may convert to FAP patients. Upon further validation, peripheral blood cell mRNA expression profiling could become an independent early diagnostic. This quantitative gene expression signature for symptomatic FAP could also become a biomarker to demonstrate significant disease-modifying effects of drugs and drug candidates. For example, when new disease modifiers are being evaluated in a FAP clinical trial, such surrogate biomarkers have the potential to provide an objective, quantitative and mechanistic molecular diagnostic of disease response to therapy.

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Biomarkers; Blood Cells; Cohort Studies; Female; Gene Expression; Gene Expression Profiling; Heterozygote; Humans; Inflammation; Male; Prealbumin; RNA; Sex Characteristics

Topics: Amyloid; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Female; Humans; Iris; Male; Middle Aged; Optic Disk; Prealbumin; Protein Aggregates; Retinal Pigment Epithelium; Vitreous Body

Topics: Adult; Amino Acid Substitution; Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Hypesthesia; Liver Transplantation; Male; Muscle Weakness; Mutation; Neuroprotective Agents; Prealbumin

Placebo-controlled clinical trials are useful for identifying the dose of a drug candidate that produces a meaningful clinical response in a patient population. Currently, Pfizer, Inc. is enrolling a 400-person clinical trial to test the efficacy of 20 or 80 mg of tafamidis to ameliorate transthyretin (TTR)-associated cardiomyopathy using clinical endpoints. Herein, we provide guidance for how to optimize the dose of tafamidis for each WT TTR cardiomyopathy patient using its mechanism of action as the key readout, i.e. we identify the dose of tafamidis that maximally kinetically stabilizes TTR in the blood. Tetramer dissociation is rate limiting for TTR aggregation, which appears to drive the pathology of the TTR amyloidoses. Hence, we measure the TTR tetramer dissociation rate (kinetic stability) in the patient's plasma as a function of tafamidis dose to optimize the dose employed to maximize kinetic stability. Historical data tell us that a subset of patients exhibiting higher tafamidis plasma concentrations are maximally kinetically stabilized at the 20-mg tafamidis dose, whereas the patient studied herein required a 60 mg once daily dose to achieve maximum kinetic stabilization. We anticipate that establishing the dose of tafamidis that achieves maximal TTR kinetic stabilization will translate into a maximal clinical effect, but that remains to be demonstrated.

Topics: Aged, 80 and over; Amyloid Neuropathies, Familial; Benzoxazoles; Cardiomyopathies; Drug Dosage Calculations; Drug Monitoring; Escherichia coli; Gene Expression; Humans; Kinetics; Male; Neuroprotective Agents; Prealbumin; Precision Medicine; Protein Stability; Recombinant Proteins

Familial amyloid polyneuropathy (FAP) is an autosomal dominant genetic disorder with systemic deposition of amyloid fibrils, and is characterized by progressive sensory, motor, and autonomic polyneuropathy. FAP was considered a rare endemic disease; however, its worldwide incidence is much higher than previously recognized. Until recently, liver transplantation was the only effective treatment for FAP. However, liver transplantation has a number of limitations, including a shortage of donors and a requirement for surgery for both the recipient and living donor. Furthermore, a large number of the patients are not good transplant candidates because of their age and/or advanced disease status. Recently, the clinical effects of two transthyretin tetramer stabilizers, diflunisal and tafamidis, were demonstrated in randomized clinical trials, and tafamidis was approved for the treatment of FAP in European countries in 2011 and Japan in 2013.

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Diflunisal; Humans; Liver Transplantation; Molecular Targeted Therapy; Prealbumin; Protein Multimerization

Familial amyloid polyneuropathy is a rare autosomal dominant disorder caused by mutations in the transthyretin gene, TTR. Diagnosis can be challenging, especially if other family members are not affected or an obvious systemic involvement is lacking. The patients are often misdiagnosed, leading to a delay in the initiation of therapy.. A 35-year-old woman of Turkish origin presented to our outpatient clinic with severe polyneuropathy associated with distally pronounced tetraparesis and hypesthesia of 2 to 3 years' duration. In addition, small nerve fiber involvement with impaired detection of cold temperatures and tingling pain in the lower legs was reported. She did not complain of autonomic dysfunction or visual disturbance. Her family history was empty regarding neuromuscular disorders. The routine diagnostic work-up was unremarkable. A sural nerve biopsy disclosed amyloid deposits, which led to the identification of a rare heterozygous transthyretin mutation (p.Glu74Gly; old classification: p.Glu54Gly).. Few cases with this very heterozygous mutation can be found in the literature. In contrast to the case of our patient, all of the previously described patients in the literature presented with additional severe autonomic symptoms, involvement of the eyes and a positive family history. In this case report, we emphasize that, in patients with progressive neuropathy with small fiber involvement, an amyloid neuropathy should be considered in the differential diagnosis, even if the family history is empty and other organs are not affected.

Topics: Adult; Amyloid Neuropathies, Familial; Benzoxazoles; Disease Progression; Fatal Outcome; Female; Genetic Linkage; Glutamic Acid; Glycine; Humans; Liver Transplantation; Mutation, Missense; Pedigree; Prealbumin

Slowing FAP progression: Tafamidis meglumine is a small molecule capable of stabilizing the transthyretin (TTR) tetramer. Tafamidis acts in a similar way to the natural hormone T4, prevents TTR amyloid fibril formation, and offers a potential alternative to liver transplantation for the treatment of patients with TTR familial amyloid polyneuropathies (TTR-FAP).

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Binding Sites; Drug Design; Humans; Mutation; Prealbumin; Protein Binding; Protein Structure, Tertiary

The treatment of familial amyloid polyneuropathies (FAP) is complex and requires a neurological and cardiological multidisciplinary coverage. It includes specific treatments to control the progression of the systemic amyloidogenesis, the symptomatic treatment of the peripheral and autonomic neuropathy (digestive, urinary, sexual, postural hypotension) and the treatment of organs severely involved by amyloidosis (heart, eyes, kidneys). First line specific treatment of met30 TTR-FAP is liver transplantation (LT) which allows to suppress the main source of mutant TTR, to stop the progression of the neuropathy in 70 % of cases at long-term (with an experience of 18 years) and to double the median survival. In case of severe renal or cardiac insufficiency, a double transplant kidney-liver or heart-liver can be discussed. The tafamidis (in temporary authorization of use in France) is a stabilizing medicine of the tetrameric TTR which showed in very early stages of met30 TTR-FAP short-term capacities to stop the progress of the peripheral neuropathy in 60 % of the cases versus 38 % with placebo. It should be proposed in case of contraindication of TH (age>70 years [20 % of the cases]), of very early stages (very low NIS-LL score), or for the period of wait of LT. Other innovative medicines issued from biopharmaceutical companies have been developed to block the hepatic production of both mutant and wild TTR which are noxious in the late forms NAH (>50 years old) (RNAi [RNA interference] therapeutics, AntiSens oligonucleotids), for removing the amyloid deposits (monoclonal antibody anti-SAP), or to slow down the formation of deposits of TTR and amyloidosis (combination of doxycycline-TUDCA). Clinical trials should be first addressed to the patients with a late onset of FAP or non-met30 TTR-FAP who are less responding to LT and patients with contraindications in the LT. Initial cardiac assessment and periodic cardiac investigations are important for the FAP according to the frequency of cardiac impairment which is responsible of high rate of mortality. Conduction disorders (atrio-ventricular blocks) require the implantation of a pacemaker in about one third of the cases during the evolution of the disease. A myocardial infiltration is detected in two third of the cases and is for a long time latent; it remains often limited to a diastolic dysfunction which can be responsible for hemodynamical difficulties during the LT; it evolves sometimes, late, towards a systol

Topics: Amyloid; Amyloid Neuropathies, Familial; Arrhythmias, Cardiac; Benzoxazoles; Early Diagnosis; Follow-Up Studies; Heart Transplantation; Humans; Kidney Transplantation; Liver Transplantation; Mutation; Prealbumin; Quality of Life; RNA Interference; RNA, Small Interfering

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Male; Neuroprotective Agents; Prealbumin

Topics: Amyloid Neuropathies, Familial; Benzoxazoles; Humans; Mutation; Neuroprotective Agents; Prealbumin