azd-6244 and Neurofibromatosis-1

To evaluate the safety and efficacy of selumetinib, a novel MEK inhibitor, for the treatment of plexiform neurofibromas (PN) in patients with neurofibromatosis type 1 (NF1).. An English-based literature search of PubMed, EMBASE, and ClinicalTrials.gov was conducted using the terms. Relevant prescribing information, abstracts, and articles identified through the search were considered for inclusion in this review.. The open-label, multicenter, single-arm, phase II SPRINT trial demonstrated clinically significant improvements in PN-related complications. Of 50 symptomatic patients, 68% experienced a partial response, with a median change in tumor volume of -27.9% from baseline. Estimated progression-free survival at 3 years was 84%. Additionally, clinically meaningful improvements were seen on patient- and parent-reported assessments evaluating pain, range of motion, disfigurement, and quality of life. Overall, the adverse effect profile for selumetinib appears mild and manageable.. Selumetinib is the first FDA-approved treatment for inoperable PN in patients with NF1, demonstrating that MEK inhibition is a promising therapeutic strategy. Studies are ongoing to assess the effect of selumetinib on other NF1-associated tumor types and to determine the optimal dosing schedule and treatment duration. Cost and treatment burden must be considered when selecting selumetinib therapy.. Selumetinib exhibits impressive antitumor activity and sustained clinical benefit in patients lacking other viable treatment options. Further studies are warranted to determine the optimal age of initiation, treatment duration, and overall cost-effectiveness of selumetinib.

Topics: Benzimidazoles; Humans; Mitogen-Activated Protein Kinase Kinases; Multicenter Studies as Topic; Neurofibroma, Plexiform; Neurofibromatosis 1; Quality of Life

Although the recent approval of selumetinib is expected to transform the management of children with neurofibromatosis type 1 (NF1), particularly those with symptomatic and inoperable plexiform neurofibromas, no systematic review has summarized its efficacy and safety based on the latest studies. This study was conducted to systematically evaluate the efficacy and safety of selumetinib in children with NF1.. Original articles reporting the efficacy and safety of selumetinib in patients with NF1 were identified in PubMed and EMBASE up to January 28, 2021. The pooled objective response rates (ORRs) and disease control rates (DCRs) were calculated using the DerSimonian-Laird method based on random-effects modeling. The pooled proportion of adverse events (AEs) was also calculated. The quality of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation system.. Five studies involving 126 patients were included in our analysis. The studies had a very low to moderate quality of the evidence. The pooled ORR was 73.8% (95% CI 57.3%-85.5%) and the DCR was 92.5% (95% CI 66.5%-98.7%). The 2 most common AEs were diarrhea, which had a pooled rate of 63.8% (95% CI 52.9%-73.4%), and an increase in creatine kinase levels, which had a pooled rate of 63.3% (95% CI 35.6%-84.3%).. Our results indicate that selumetinib is an effective and safe treatment for pediatric patients with symptomatic, inoperable plexiform neurofibromas. Further larger-scale randomized controlled studies are needed to confirm the long-term outcome of patients treated with this drug.

Topics: Benzimidazoles; Child; Diarrhea; Humans; Neurofibroma, Plexiform; Neurofibromatosis 1

Topics: Antibodies, Monoclonal, Humanized; Antiparasitic Agents; Benzimidazoles; Child; Dermatologic Agents; Histiocytosis, Langerhans-Cell; Humans; Ivermectin; Netherton Syndrome; Neurofibromatosis 1; Scabies; Skin Diseases; Vemurafenib

Patients with neurofibromatosis type 1 (NF1) are at increased risk for benign and malignant neoplasms. Recently, targeted therapy with the MEK inhibitor class has helped address these needs. We highlight recent successes with selumetinib while acknowledging ongoing challenges for NF1 patients and future directions.. MEK inhibitors have demonstrated efficacy for NF1-related conditions, including plexiform neurofibromas and low-grade gliomas, two common causes of NF1-related morbidity. Active investigations for NF1-related neoplasms have benefited from advanced understanding of the genomic and cell signaling alterations in these conditions and development of sound preclinical animal models. Selumetinib has become the first FDA-approved targeted therapy for NF1 following its demonstrated efficacy for inoperable plexiform neurofibroma. Investigations of combination therapy and the development of a representative NF1 swine model hold promise for translating therapies for other NF1-associated pathology.

Topics: Animals; Benzimidazoles; Clinical Trials as Topic; Disease Models, Animal; Humans; Mitogen-Activated Protein Kinase Kinases; Neurofibroma, Plexiform; Neurofibromatosis 1; Precision Medicine; Protein Kinase Inhibitors; Signal Transduction; Swine

Conducting clinical research in patients with rare diseases presents a variety of challenges. At the same time, rare diseases represent a large area of unmet medical need with a significant burden of morbidity throughout the world. One of the most common issues with designing clinical trials for rare disease populations is that the gold-standard randomized controlled trial design is often not feasible in these small and usually geographically dispersed populations. Real world data therefore has particular relevance in the rare disease setting, where it may be used as a comparator for single-arm treatment trials and in support of submissions to regulatory agencies for drugs to treat these conditions. In this report, we review the potential utility and limitations of external controls for regulatory approval of drugs in rare diseases and present a recent case example of the successful utilization of external controls in the Neurofibromatosis type 1 (NF1) population.

Topics: Benzimidazoles; Drug Approval; Humans; Neurofibromatosis 1; Pragmatic Clinical Trials as Topic; Randomized Controlled Trials as Topic; Rare Diseases; United States; United States Food and Drug Administration

Neurofibromatosis type 1 (NF-1), also known as von Recklinghausen's disease, is an autosomal dominant dysplasia of the ectoderm and mesoderm with a variable clinical expression, but near-complete penetrance before the age of 5 years. The estimated incidence is 1 in 3000 births. NF-1 is characterized by collections of neurofibromas, café-au-lait spots, axillary and inguinal freckling, and pigmented hamartomas in the iris (Lisch nodules). Pulmonary manifestations of NF-1, which usually include bilateral basal reticulations and apical bullae and cysts, are reported in 10-20% of adult patients. Clinically, neurofibromatosis-associated diffuse lung disease (NF-DLD) usually presents with nonspecific respiratory symptoms, including dyspnea on exertion, shortness of breath, and chronic cough or chest pain, at the time of diagnosis. Computed tomography (CT) is highly accurate for the identification and characterization of NF-DLD; it is the most reliable method for the diagnosis of this lung involvement. Various CT findings of NF-DLD, including cysts, bullae, ground-glass opacities, bibasilar reticular opacities, and emphysema, have been described in patients with NF-1. The typical CT pattern, however, is characterized by upper-lobe cystic and bullous disease, and basilar interstitial lung disease. Currently, the goal of NF-DLD treatment is the earliest possible diagnosis, focusing on symptom relief and interventions that positively alter the course of the disease, such as smoking cessation. The aim of this review is to describe the main clinical, pathological, and imaging aspects of NF-1, with a focus on pulmonary involvement.

Topics: Acrylonitrile; Aged; Aniline Compounds; Antineoplastic Agents; Benzimidazoles; Blister; Child; Female; Genetic Counseling; Humans; Hypertension, Pulmonary; Lung Diseases; Lung Diseases, Interstitial; Male; Middle Aged; Neurofibromatosis 1; Pulmonary Emphysema; Tomography, X-Ray Computed; Tretinoin; Young Adult

Selumetinib shrank inoperable symptomatic plexiform neurofibromas (PN) in children with neurofibromatosis type 1 (NF1) and provided clinical benefit for many in our previously published phase 1/2 clinical trials (SPRINT, NCT01362803). At the data cutoff (DCO) of the prior publications, 65% of participants were still receiving treatment. This report presents up to 5 years of additional safety and efficacy data from these studies.. This manuscript includes data from the phase 1 and phase 2, stratum 1 study which included participants with clinically significant PN-related morbidity. Participants received continuous selumetinib dosing (1 cycle = 28 days). Safety and efficacy data through February 27, 2021 are included. PN response assessed by volumetric magnetic resonance imaging analysis: Confirmed partial response (cPR) ≥20% decrease from baseline on 2 consecutive evaluations. Phase 2 participants completed patient-reported outcome measures assessing tumor pain intensity (Numeric Rating Scale-11) and interference of pain in daily life (pain interference index).. For the 74 children (median age 10.3 years; range 3-18.5) enrolled, overall cPR rate was 70% (52/74); median duration of treatment was 57.5 cycles (range 1-100). Responses were generally sustained with 59% (44) lasting ≥ 12 cycles. Tumor pain intensity (n = 19, P = .015) and pain interference (n = 18, P = .0059) showed durable improvement from baseline to 48 cycles. No new safety signals were identified; however, some developed known selumetinib-related adverse events (AEs) for the first time after several years of treatment.. With up to 5 years of additional selumetinib treatment, most children with NF1-related PN had durable tumor shrinkage and sustained improvement in pain beyond that previously reported at 1 year. No new safety signals were identified; however, ongoing monitoring for known selumetinib-related AEs is needed while treatment continues.

Topics: Benzimidazoles; Child; Humans; Neurofibroma, Plexiform; Neurofibromatosis 1; Pain

Selumetinib was recently approved for the treatment of inoperable symptomatic plexiform neurofibromas (PNs) in children with neurofibromatosis type 1 (NF1). This parallel phase II study determined the response rate to selumetinib in children with NF1 PN without clinically significant morbidity.. Children with NF1 and inoperable PNs, which were not yet causing clinically significant morbidity but had the potential to cause symptoms, received selumetinib at 25 mg/m2 orally twice daily (1 cycle = 28 days). Volumetric magnetic resonance imaging analysis and outcome assessments, including patient-reported (PRO), observer-reported, and functional outcome measures were performed every 4 cycles for 2 years, with changes assessed over time. A confirmed partial response (cPR) was defined as PN volume decrease of ≥20% on at least 2 consecutive scans ≥3 months apart.. 72% of subjects experienced a cPR on selumetinib. Participants received selumetinib for a median of 41 cycles (min 2, max 67) at data cutoff. Approximately half of the children rated having some target tumor pain at baseline, which significantly decreased by pre-cycle 13. Most objectively measured baseline functions, including visual, motor, bowel/bladder, or airway function were within normal limits and did not clinically or statistically worsen during treatment.. Selumetinib resulted in PN shrinkage in most subjects with NF1 PN without clinically significant morbidity. No new PN-related symptoms developed while on selumetinib, and PRO measures indicated declines in tumor-related pain intensity. This supports that selumetinib treatment may prevent the development of PN-related morbidities, though future prospective studies are needed to confirm these results.. ClinicalTrials.gov NCT01362803.

Topics: Benzimidazoles; Child; Humans; Morbidity; Neurofibroma, Plexiform; Neurofibromatosis 1; Pain

Pediatric low-grade gliomas (pLGGs) are the most common childhood brain tumor. Progression-free survival (PFS) is much lower than overall survival, emphasizing the need for alternative treatments. Sporadic (without neurofibromatosis type 1) optic pathway and hypothalamic gliomas (OPHGs) are often multiply recurrent and cause significant visual deficits. Recently, there has been a prioritization of functional outcomes.. We present results from children with recurrent/progressive OPHGs treated on a PBTC (Pediatric Brain Tumor Consortium) phase II trial evaluating efficacy of selumetinib (AZD6244, ARRY-142886) a MEK-1/2 inhibitor. Stratum 4 of PBTC-029 included patients with sporadic recurrent/progressive OPHGs treated with selumetinib at the recommended phase II dose (25mg/m2/dose BID) for a maximum of 26 courses.. Twenty-five eligible and evaluable patients were enrolled with a median of 4 (1-11) previous therapies. Six of 25 (24%) had partial response, 14/25 (56%) had stable disease, and 5 (20%) had progressive disease while on treatment. The median treatment courses were 26 (2-26); 14/25 patients completed all 26 courses. Two-year PFS was 78 ± 8.5%. Nineteen of 25 patients were evaluable for visual acuity which improved in 4/19 patients (21%), was stable in 13/19 (68%), and worsened in 2/19 (11%). Five of 19 patients (26%) had improved visual fields and 14/19 (74%) were stable. The most common toxicities were grade 1/2 CPK elevation, anemia, diarrhea, headache, nausea/emesis, fatigue, AST and ALT increase, hypoalbuminemia, and rash.. Selumetinib was tolerable and led to responses and prolonged disease stability in children with recurrent/progressive OPHGs based upon radiographic response, PFS, and visual outcomes.

Topics: Benzimidazoles; Brain Neoplasms; Child; Humans; Neurofibromatosis 1; Optic Nerve Glioma

Plexiform neurofibromas (PN) are the most frequent tumors associated with Neurofibromatosis type 1 (NF-1). PN can cause significant complications, including pain, functional impairment, and disfigurement. There is no efficient medical treatment and, surgical resection of large PN is frequently infeasible. Selumetinib (AZD6244/ARRY-142886) is a mitogen-activated protein kinase enzyme (MEK1/2) inhibitor and works by targeting the MAPK pathway. It is an investigational treatment option for inoperable symptomatic PN associated with NF-1. Herein, we describe a single institutional experience with selumetinib for inoperable PN in NF-1.. Case series study of demographics, clinical, baseline characteristics, treatment effect, and follow-up of consecutive genetically confirmed NF1 patients with inoperable PN associated with significant or potential significant morbidity treated with selumetinib (April 2018 to April 2019).. Nineteen patients were treated with selumetinib. Predominant target locations were head and neck (31.6%, 6/19), chest (26.3%, 5/19) and pelvis (21%, 4/19) and the most important comorbidities were disfigurement (47.4%, 9/19) and pain (26.3%, 5/19). The mean follow-up time was 223 days (range 35-420 days). All but one had sustained clinical improvement, mainly in the first 60-90 days of treatment. In one patient, the treatment was suspended after 168 days (lack of clear benefit and left ventricular ejection fraction drop). There were no adverse effects leading to treatment suspension.. In the first observational study of selumetinib for NF-1 associated PN we showed that the drug was associated with clinical and radiological improvement. Our study also confirms the safety described in the clinical trials.

Topics: Adolescent; Adult; Benzimidazoles; Child; Child, Preschool; Female; Follow-Up Studies; Humans; Male; Neurofibroma, Plexiform; Neurofibromatosis 1; Prognosis; Stroke Volume; Young Adult

No approved therapies exist for inoperable plexiform neurofibromas in patients with neurofibromatosis type 1.. We conducted an open-label, phase 2 trial of selumetinib to determine the objective response rate among patients with plexiform neurofibromas and to assess clinical benefit. Children with neurofibromatosis type 1 and symptomatic inoperable plexiform neurofibromas received oral selumetinib twice daily at a dose of 25 mg per square meter of body-surface area on a continuous dosing schedule (28-day cycles). Volumetric magnetic resonance imaging and clinical outcome assessments (pain, quality of life, disfigurement, and function) were performed at least every four cycles. Children rated tumor pain intensity on a scale from 0 (no pain) to 10 (worst pain imaginable).. A total of 50 children (median age, 10.2 years; range, 3.5 to 17.4) were enrolled from August 2015 through August 2016. The most frequent neurofibroma-related symptoms were disfigurement (44 patients), motor dysfunction (33), and pain (26). A total of 35 patients (70%) had a confirmed partial response as of March 29, 2019, and 28 of these patients had a durable response (lasting ≥1 year). After 1 year of treatment, the mean decrease in child-reported tumor pain-intensity scores was 2 points, considered a clinically meaningful improvement. In addition, clinically meaningful improvements were seen in child-reported and parent-reported interference of pain in daily functioning (38% and 50%, respectively) and overall health-related quality of life (48% and 58%, respectively) as well as in functional outcomes of strength (56% of patients) and range of motion (38% of patients). Five patients discontinued treatment because of toxic effects possibly related to selumetinib, and 6 patients had disease progression. The most frequent toxic effects were nausea, vomiting, or diarrhea; an asymptomatic increase in the creatine phosphokinase level; acneiform rash; and paronychia.. In this phase 2 trial, most children with neurofibromatosis type 1 and inoperable plexiform neurofibromas had durable tumor shrinkage and clinical benefit from selumetinib. (Funded by the Intramural Research Program of the National Institutes of Health and others; ClinicalTrials.gov number, NCT01362803.).

Topics: Adolescent; Benzimidazoles; Child; Child, Preschool; Female; Humans; Male; Mitogen-Activated Protein Kinase Kinases; Nausea; Neurofibroma, Plexiform; Neurofibromatosis 1; Pain; Patient Reported Outcome Measures; Progression-Free Survival; Protein Kinase Inhibitors; Tumor Burden

Effective medical therapies are lacking for the treatment of neurofibromatosis type 1-related plexiform neurofibromas, which are characterized by elevated RAS-mitogen-activated protein kinase (MAPK) signaling.. We conducted a phase 1 trial of selumetinib (AZD6244 or ARRY-142886), an oral selective inhibitor of MAPK kinase (MEK) 1 and 2, in children who had neurofibromatosis type 1 and inoperable plexiform neurofibromas to determine the maximum tolerated dose and to evaluate plasma pharmacokinetics. Selumetinib was administered twice daily at a dose of 20 to 30 mg per square meter of body-surface area on a continuous dosing schedule (in 28-day cycles). We also tested selumetinib using a mouse model of neurofibromatosis type 1-related neurofibroma. Response to treatment (i.e., an increase or decrease from baseline in the volume of plexiform neurofibromas) was monitored by using volumetric magnetic resonance imaging analysis to measure the change in size of the plexiform neurofibroma.. A total of 24 children (median age, 10.9 years; range, 3.0 to 18.5) with a median tumor volume of 1205 ml (range, 29 to 8744) received selumetinib. Patients were able to receive selumetinib on a long-term basis; the median number of cycles was 30 (range, 6 to 56). The maximum tolerated dose was 25 mg per square meter (approximately 60% of the recommended adult dose). The most common toxic effects associated with selumetinib included acneiform rash, gastrointestinal effects, and asymptomatic creatine kinase elevation. The results of pharmacokinetic evaluations of selumetinib among the children in this trial were similar to those published for adults. Treatment with selumetinib resulted in confirmed partial responses (tumor volume decreases from baseline of ≥20%) in 17 of the 24 children (71%) and decreases from baseline in neurofibroma volume in 12 of 18 mice (67%). Disease progression (tumor volume increase from baseline of ≥20%) has not been observed to date. Anecdotal evidence of decreases in tumor-related pain, disfigurement, and functional impairment was observed.. Our early-phase data suggested that children with neurofibromatosis type 1 and inoperable plexiform neurofibromas benefited from long-term dose-adjusted treatment with selumetinib without having excess toxic effects. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01362803 .).

Topics: Adolescent; Animals; Benzimidazoles; Child; Child, Preschool; Disease Models, Animal; Disease Progression; Female; Humans; Magnetic Resonance Imaging; Male; Mice; Mitogen-Activated Protein Kinase Kinases; Neurofibroma, Plexiform; Neurofibromatosis 1; Protein Kinase Inhibitors

Plexiform neurofibromas are benign neoplasms that develop in 20-50% children with neurofibromatosis type 1 (NF1). Selumetinib was approved as treatment for symptomatic and inoperable plexiform neurofibromas. Subclinical left ventricular ejection fraction reduction is a less common effect of selumetinib.. We aimed to investigate the contractile function of the heart in a cohort of children with NF1 treated with selumetinib.. We designed a cross-sectional study including 17 patients with NF1 who received selumetinib. Echocardiographic parameters were compared with a cohort of 17 healthy children matched by sex and age and another group of 17 children with untreated NF1.. Compared with healthy controls, patients with NF1 treated with selumetinib had lower mean values of global longitudinal strain (- 22.9 ± 2% vs -25.5 ± 2%; p = 0.001), fractional shortening (36 ± 4% vs 43 ± 8%; p = 0.02) and tricuspid annular plane systolic excursion (19 ± 3 mm vs 23 ± 2 mm; p = 0.001); no difference was found in left ventricular ejection fraction (63 ± 4% vs 65 ± 3%; p = 0.2 respectively). Median treatment time with selumetinib at the time of the echocardiographic evaluation was 22 ± 16 months.. Patients with NF1 treated with selumetinib may experience subtle changes in systolic function identified by global longitudinal strain and not revealed by left ventricular ejection fraction. Global longitudinal strain might be useful to monitor cardiac function in this cohort of patients for the duration of therapy.

Topics: Child; Cross-Sectional Studies; Echocardiography; Global Longitudinal Strain; Humans; Neurofibroma, Plexiform; Neurofibromatosis 1; Stroke Volume; Ventricular Function, Left

患儿　女，5岁5月龄，因“皮肤咖啡牛奶斑5年余，跛行伴易跌倒1年余”就诊，临床表现为运动障碍、颈部包块、全身多处咖啡牛奶斑、脊柱侧弯，超声和影像学检查提示多发不规则团块状软组织信号，诊断1型神经纤维瘤病。口服司美替尼（2次/d，早20 mg，晚10 mg）治疗第37天颈部包块肉眼可见缩小，走路易跌倒明显减少，跛行、脊柱侧弯减轻，咖啡牛奶斑颜色变淡、范围缩小；治疗第57天后走路再无跌倒现象。.

Topics: Benzimidazoles; Child; Humans; Neurofibromatosis 1

Selumetinib is a promising MAP (mitogen-activated protein) kinase (MEK) 1/2 inhibitor treatment for pediatric low-grade gliomas. We hypothesized that MR imaging-derived ADC histogram metrics would be associated with survival and response to treatment with selumetinib.. Children with recurrent, refractory, or progressive pediatric low-grade gliomas who had World Health Organization grade I pilocytic astrocytoma with. Each stratum comprised 25 patients. Stratum 1 responders showed lower values of SD of baseline ADC_total as well as a larger decrease with time on treatment in ADC_total mean, mode, and median compared with nonresponders. Stratum 3 responders showed a greater longitudinal decrease in ADC_total. In stratum 4, higher baseline ADC_total skewness and kurtosis were associated with shorter progression-free survival. When all 3 strata were combined, responders showed a greater decrease with time in ADC_total mode and median. Compared with sporadic OPHG, neurofibromatosis type 1-associated OPHG had lower values of ADC_total mean, mode, and median as well as ADC_enhancement mean and median and higher values of ADC_total skewness and kurtosis at baseline. The longitudinal decrease in ADC_total median during treatment was significantly greater in sporadic OPHG compared with neurofibromatosis type 1-associated OPHG.. ADC histogram metrics are associated with progression-free survival and response to treatment with selumetinib in pediatric low-grade gliomas.

Topics: Benzimidazoles; Brain Neoplasms; Child; Diffusion Magnetic Resonance Imaging; Glioma; Humans; Neurofibromatosis 1; Proto-Oncogene Proteins B-raf

Neurofibromatosis type 1-associated plexiform neurofibromas can cause debilitating symptoms and be life threatening. Treatment options are limited, given their tendency to regrow following surgery and their propensity to transform into malignant tumours following radiation. Selumetinib is an oral selective inhibitor of RAS-mitogen-activated protein kinase (MAPK) 1 and 2, which has shown efficacy for tumour shrinkage/stabilisation and symptom improvement. We report a national case series of 19 children treated with selumetinib. All patients experienced symptom improvement or stabilisation with an acceptable toxicity profile, including those patients previously treated with trametinib. This real-world experience confirms previous trials showing significant clinical benefit for this patient population.

Topics: Benzimidazoles; Child; Humans; Neurofibroma, Plexiform; Neurofibromatosis 1

Selumetinib is a MEK inhibitor, which is effective with an acceptable safety profile in reducing the volume of symptomatic inoperable plexiform neurofibromas in some clinical trials and also has been recently approved by FDA for use in children aged 2 years or older. However, no systematic review has yet been performed to provide a collective estimate of the results of all these trials.. Articles describing the use of selumetinib in patients with neurofibromatosis type-1 (NF1) with inoperable plexiform neurofibromas were searched from different electronic databases. The objectives were to provide a pooled estimate of efficacy evaluated by direct measurement and also by various functional measures, as well as the proportion of patients with adverse events. For determining pooled estimates, we included only studies with a minimum sample size of 15 with a prospective study design.. A total of eight articles with 137 patients were found and 134 patients in six uncontrolled trials were included in the quantitative review. Out of these 26 were adults (69% male; 33.2±18.4 years, range 18-60 years) and 108 were in the pediatric age group (74% boys, 10.9±2.3 years, range-2-18 years,). Total 77.86% (95% CI: 55.91-99.81%) patients had a partial response, 71.24% (95% CI: 53.62-89.93%) had a confirmed partial response, and 56.25% (95% CI: 37.53-72.49%) had a durable partial response. The average time to initial response was 7.3±2.9 cycles (range, 4 to 20), and the median time to best response was 15.4±5.8 cycles (range, 4 to 36). The average change in neurofibroma volume at best response was -28.15% (95% CI: -17.95%, -38.34%, range, -55.1% to 2.2%). Progression-free survival was observed in 93.12% of patients at the time of data cut-off. Overall, 73.26% (95% CI: 54.07%, 92.45%) patients had improvement in at least one of the functional or patient-reported outcome assessments. The most common adverse effects were grade 1 and 2 gastrointestinal symptoms (65%), an asymptomatic increase in the creatine phosphokinase level (31%), paronychia (6%), and acneiform rash (17%). A total of 17% patients required dose reduction due to these toxic effects and 10.5% (95% CI: 4.0%, 17.0%) of patients discontinued due to toxic effects.. Selumetinib can produce sustained shrinkage in the majority of patients with NF1 and symptomatic plexiform neurofibroma to provide clinically meaningful benefit in functional ability, with more robust evidence in children. The acceptable safety profile and absence of cumulative toxic effects permit long-term treatment with selumetinib.

Topics: Adult; Benzimidazoles; Child; Female; Humans; Male; Neurofibroma, Plexiform; Neurofibromatosis 1; Prospective Studies

Topics: Benzimidazoles; Child; Doxycycline; Drug-Related Side Effects and Adverse Reactions; Exanthema; Humans; Neurofibroma, Plexiform; Neurofibromatosis 1

Elephantiasis neuromatosa (EN) is a rare and extreme form of plexiform neurofibroma in patients with neurofibromatosis type 1 (NF1). EN is often associated with significant morbidity and remains difficult to treat. We present a case of an 11-year-old female with NF1 whose thoracolumbar plexiform neurofibroma and lower extremity EN exhibited clinical improvement from treatment with selumetinib, a selective MEK inhibitor.

Topics: Benzimidazoles; Child; Elephantiasis; Female; Humans; Mitogen-Activated Protein Kinase Kinases; Neurofibroma, Plexiform; Neurofibromatosis 1

Plexiform neurofibroma (PN) is one of the most striking clinical features of neurofibromatosis 1. Growth of PN can occur at any stage of life but mostly in childhood and during hormonal changes. They arise from multiple nerve fascicles and may transform into malignant peripheral nerve sheath tumors. There was previously no approved medical therapy for tumor shrinkage or regression. Surgery is not always possible due to inaccessible location, involvement of vital tissue, optimal timing, and incomplete removal. Recently, the US Food and Drug Administration approved selumetinib for pediatric patients, 2 years of age and older, with neurofibromatosis type 1 who have symptomatic, inoperable tumor. Neurofibromin, a 2818 amino acid long cytoplasmic protein, is the product of the NF1 gene. It inhibits the activity of Ras GTPase proteins. Lack of functional neurofibromin in patients with NF1 leads to dysregulated Ras and tumorigenesis. RAS MAPK pathway is hyper activated in NF1. Selumetinib is an inhibitor of MEK1 and MEK2 proteins, which play an important role in the MAPK signaling pathway related to tumor growth. Approval was based on one pivotal, single-arm, phase II trial. 70% of participants experienced confirmed partial response of tumor shrinkage, and 68% also had improvement of related complications, and other studies have also shown beneficial responses. The major limitation of this molecule regarding its mechanism of action is the dose-dependent effect of MEK inhibition in growth of neurofibroma. Long-term safety and efficacy studies are to be done in the future to establish selumetininb as a useful medicine.

Topics: Benzimidazoles; Child; Humans; Neurofibroma, Plexiform; Neurofibromatosis 1; Pharmaceutical Preparations; United States

Selumetinib (ARRY-142886) is a potent, selective, MEK1/2 inhibitor approved in the US for the treatment of children (≥ 2 years) with neurofibromatosis type 1 (NF1) and symptomatic, inoperable plexiform neurofibromas (PN). We characterized population pharmacokinetics (PK) of selumetinib and its active N-desmethyl metabolite, evaluated exposure-safety/efficacy relationships, and assessed the proposed therapeutic dose of 25 mg/m. Population PK modeling and covariate analysis (demographics, formulation, liver enzymes, BSA, patients/healthy volunteers) were based on pooled PK data from adult healthy volunteers (n = 391), adult oncology patients (n = 83) and pediatric patients with NF1-PN (n = 68). Longitudinal selumetinib/metabolite exposures were predicted with the final model. Exposure-safety/efficacy analyses were applied to pediatric patients (dose levels: 20, 25, 30 mg/m. Selumetinib and metabolite concentration-time courses were modeled using a joint compartmental model. Typical selumetinib plasma clearance was 11.6 L/h (95% CI 11.0-12.2 L/ h). Only BSA had a clinically relevant (> 20%) impact on exposure, supporting BSA-based administration in children. Selumetinib and metabolite exposures in responders (≥ 20% PN volume decrease from baseline) and non-responders were largely overlapping, with medians numerically higher in responders. No clear relationships between exposure and safety events were established; exposure was not associated with key adverse events (AEs) including rash acneiform, diarrhea, vomiting, and nausea.. Findings support continuous selumetinib 25 mg/m

Topics: Adolescent; Adult; Benzimidazoles; Child; Child, Preschool; Female; Healthy Volunteers; Humans; Longitudinal Studies; Male; Neurofibroma, Plexiform; Neurofibromatosis 1; Protein Kinase Inhibitors; Young Adult

Topics: Adolescent; Antineoplastic Agents; Benzimidazoles; Humans; Lower Extremity; Male; Mitogen-Activated Protein Kinase Kinases; Neurofibroma, Plexiform; Neurofibromatosis 1

Persistent signalling via the PI3K/AKT/mTOR pathway is a major driver of malignancy in NF1-associated malignant peripheral nerve sheath tumours (MPNST). Nevertheless, single targeting of this pathway is not sufficient to inhibit MPNST growth. In this report, we demonstrate that combined treatment with the allosteric pan-AKT inhibitor MK-2206 and the mTORC1/mTORC2 inhibitor AZD8055 has synergistic effects on the viability of MPNST cell lines in comparison to the treatment with each compound alone. However, when treating animals bearing experimental MPNST with the combined AKT/mTOR regime, no influence on tumour growth was observed. Further analysis of the MPNST xenograft tumours resistant to AKT/mTOR treatment revealed a reactivation of both AKT and mTOR in several tumour samples. Additional targeting of the RAS/RAF/MEK/MAPK pathway with the allosteric MEK1/2 inhibitor AZD6244 showed synergistic effects on the viability of MPNST cell lines in vitro in comparison to the dual AKT/mTOR inhibition. In summary, these data indicate that combined treatment with AKT and mTOR inhibitors is effective on MPNST cells in vitro but tumour resistance can occur rapidly in vivo by restoration of AKT/mTOR signalling. Our data further suggest that a triple treatment with inhibitors against AKT, mTORC1/2 and MEK1/2 may be a promising treatment option that should be further analysed in an experimental MPNST mouse model in vivo.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Benzimidazoles; Cell Line, Tumor; Cell Proliferation; Drug Synergism; Heterocyclic Compounds, 3-Ring; Humans; Mice, SCID; Morpholines; Neurofibromatosis 1; Neurofibrosarcoma; Proto-Oncogene Proteins c-akt; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Topics: Benzimidazoles; Child; Humans; Neurofibroma, Plexiform; Neurofibromatosis 1

Plexiform neurofibromas (PN) are congenital tumors that affect up to 50% of individuals with neurofibromatosis type 1. Despite their benign nature, they can grow rapidly and cause severe morbidities. Selumetinib, an inhibitor of mitogen-activated protein kinase (MEK) 1 and 2, was reported to induce a clinical response in pediatric subjects with inoperable PN.. The aim of this paper is to describe a prospective case series of patients treated with selumetinib with emphasis on drug adverse events.. All the subjects who received selumetinib at the Pediatric Department of Scientific Research Institute and Hospital "Burlo Garofolo", from November 2017 to January 2020, were progressively included. We monitored the patients with a follow-up visit every 3 months. MRI or CT scans to monitor the growth of the tumor were performed after 3 months of treatment, and then every 6-9 months.. Selumetinib was prescribed to nine children, with a total of 17 inoperable PN. The mean follow-up period was 12 months. During the follow-up, one patient experienced an ischemic stroke, unrelated to the treatment. Only minor adverse events were observed: six individuals developed gastrointestinal side effects, seven patients presented a mild form of acne, six had paronychia, four developed irritability, and two showed a mild increase in creatine kinase. None of the patients stopped the treatment. Tumor reduction > 20% was recorded in 16 out of 17 PN (94%). One PN remained stable. No tumor growth was recorded during the treatment.. In this case series, selumetinib appears to be effective and safe for the pediatric population.

Topics: Adolescent; Benzimidazoles; Child; Child, Preschool; Female; Humans; Magnetic Resonance Imaging; Male; MAP Kinase Kinase 1; Neurofibroma, Plexiform; Neurofibromatosis 1; Prospective Studies

Topics: Benzimidazoles; Child; Glioma; Humans; Imatinib Mesylate; Mitogen-Activated Protein Kinases; Nerve Sheath Neoplasms; Neurofibroma, Plexiform; Neurofibromatosis 1; Neurofibromin 1; Protein Kinase Inhibitors

Topics: Benzimidazoles; Child; Glioma; Humans; Neurofibromatosis 1; Proto-Oncogene Proteins B-raf

Plexiform neurofibromas (PNs), which may be present at birth in up to half of children with type 1 neurofibromatosis (NF1), can cause serious loss of function, such as quadriparesis, and can undergo malignant transformation. Surgery is the first line treatment although the invasive nature of these tumors often prevents complete resection. Recent clinical trials have shown promising success for some drugs, notably selumetinib, an inhibitor of MAP kinase kinase (MEK). We have developed three-dimensional (3D) cell culture models of immortalized cells from NF1 PNs and of control Schwann cells (SCs) that we believe mimic more closely the in vivo condition than conventional two-dimensional (2D) cell culture. Our goal is to facilitate pre-clinical identification of potential targeted therapeutics for these tumors. Three drugs, selumetinib (a MEK inhibitor), picropodophyllin (an IGF-1R inhibitor) and LDN-193189 (a BMP2 inhibitor) were tested with dose-response design in both 2D and 3D cultures for their abilities to block net cell growth. Cell lines grown in 3D conditions showed varying degrees of resistance to the inhibitory actions of all three drugs. For example, control SCs became resistant to growth inhibition by selumetinib in 3D culture. LDN-193189 was the most effective drug in 3D cultures, with only slightly reduced potency compared to the 2D cultures. Characterization of these models also demonstrated increased proteolysis of collagen IV in the matrix by the PN driver cells as compared to wild-type SCs. The proteolytic capacity of the PN cells in the model may be a clinically significant property that can be used for testing the ability of drugs to inhibit their invasive phenotype.

Topics: Antineoplastic Agents; Benzimidazoles; Bone Morphogenetic Protein 2; Cell Culture Techniques; Cells, Cultured; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; Genes, Neurofibromatosis 1; Genes, Reporter; Humans; Luminescent Proteins; MAP Kinase Kinase 1; Molecular Targeted Therapy; Neurofibroma, Plexiform; Neurofibromatosis 1; Phenotype; Podophyllotoxin; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; Receptor, IGF Type 1; Red Fluorescent Protein; Schwann Cells; Transduction, Genetic; Tumor Cells, Cultured

Topics: Benzimidazoles; Humans; Nerve Sheath Neoplasms; Neurofibroma, Plexiform; Neurofibromatosis 1