bay-63-2521 and Scleroderma--Systemic

The NO/sGC/cGMP signaling cascade plays a pivotal role in regulation of cardiovascular, cardiopulmonary and cardiorenal diseases and impairment of this cascade results in severe pathologies. Therefore, pharmacological interventions, targeting this pathway are promising strategies for treating a variety of diseases. Nitrates, supplementing NO and, PDE5 inhibitors preventing cGMP degradation, are used for angina pectoris treatment and the treatment of pulmonary arterial hypertension (PAH), respectively. More recently, a new class of drugs which directly stimulate the sGC enzyme and trigger NO-independent cGMP production was introduced and termed sGC stimulators. In 2013, the first sGC stimulator, riociguat, was approved for the treatment of PAH and chronic thromboembolic pulmonary hypertension (CTEPH). Since cGMP targets multiple intracellular downstream targets, sGC stimulators have shown - beyond the well characterized vasodilatation - anti-fibrotic, anti-inflammatory and anti-proliferative effects. These additional modes of action might extend the therapeutic potential of this drug class substantially. This review summarizes the NO/sGC/cGMP signaling cascades, the discovery and the mode of action of sGC stimulators. Furthermore, the preclinical evidence and development of riociguat for the treatment of PAH and CTEPH is reviewed. Finally, a summary of the antifibrotic effects of sGC stimulators, especially the most recent finding for skin fibrosis are included which may indicate efficacy in fibrotic diseases like Systemic Sclerosis (SSc).

Topics: Cyclic GMP; Enzyme Activators; Humans; Hypertension, Pulmonary; Nitric Oxide; Pyrazoles; Pyrimidines; Rare Diseases; Scleroderma, Systemic; Soluble Guanylyl Cyclase

Systemic sclerosis (SSc) is a systemic autoimmune disease characterized by vasculopathy, inflammation and fibrosis. These three main disease-determining pathways are the target of the currently available treatments used to possibly modify the progression of disease-related manifestations, although this synergy has not been fully applied on SSc joint, skin or lung involvement yet. Areas covered: we describe the current status of SSc treatment/therapy performing a literature search in MEDLINE/Pubmed and Thomson Reuter's Web of Science for articles published until March 2016. Moreover, ongoing registered clinical trials (RCTs) on SSc were searched through clinicaltrials.gov website. Expert commentary: presently, promising drugs are under evaluation to target the different pathogenic pathways of systemic sclerosis: Tocilizumab and Abatacept for skin and lung fibrosis; Riociguat and Selexipag are approved for pulmonary arterial hypertension but promising anti-fibrotic effects are now being studied. Finally, several anti-fibrotic molecules are currently involved in RCTs, such as Nintedanib, IVA-337, Terguride.

Topics: Abatacept; Acetamides; Antibodies, Monoclonal, Humanized; Biological Products; Clinical Trials as Topic; Fibrinolytic Agents; Fibrosis; Humans; Hypertension, Pulmonary; Indoles; Inflammation; Joints; Lisuride; Lung; PubMed; Pyrazines; Pyrazoles; Pyrimidines; Scleroderma, Systemic; Skin

The aim was to update the 2009 European League against Rheumatism (EULAR) recommendations for the treatment of systemic sclerosis (SSc), with attention to new therapeutic questions. Update of the previous treatment recommendations was performed according to EULAR standard operating procedures. The task force consisted of 32 SSc clinical experts from Europe and the USA, 2 patients nominated by the pan-European patient association for SSc (Federation of European Scleroderma Associations (FESCA)), a clinical epidemiologist and 2 research fellows. All centres from the EULAR Scleroderma Trials and Research group were invited to submit and select clinical questions concerning SSc treatment using a Delphi approach. Accordingly, 46 clinical questions addressing 26 different interventions were selected for systematic literature review. The new recommendations were based on the available evidence and developed in a consensus meeting with clinical experts and patients. The procedure resulted in 16 recommendations being developed (instead of 14 in 2009) that address treatment of several SSc-related organ complications: Raynaud's phenomenon (RP), digital ulcers (DUs), pulmonary arterial hypertension (PAH), skin and lung disease, scleroderma renal crisis and gastrointestinal involvement. Compared with the 2009 recommendations, the 2016 recommendations include phosphodiesterase type 5 (PDE-5) inhibitors for the treatment of SSc-related RP and DUs, riociguat, new aspects for endothelin receptor antagonists, prostacyclin analogues and PDE-5 inhibitors for SSc-related PAH. New recommendations regarding the use of fluoxetine for SSc-related RP and haematopoietic stem cell transplantation for selected patients with rapidly progressive SSc were also added. In addition, several comments regarding other treatments addressed in clinical questions and suggestions for the SSc research agenda were formulated. These updated data-derived and consensus-derived recommendations will help rheumatologists to manage patients with SSc in an evidence-based way. These recommendations also give directions for future clinical research in SSc.

Topics: Angiotensin-Converting Enzyme Inhibitors; Delphi Technique; Endothelin Receptor Antagonists; Europe; Fingers; Fluoxetine; Gastrointestinal Diseases; Glucocorticoids; Hematopoietic Stem Cell Transplantation; Humans; Hypertension, Pulmonary; Kidney Diseases; Lung Diseases; Phosphodiesterase 5 Inhibitors; Prostaglandins I; Pyrazoles; Pyrimidines; Raynaud Disease; Rheumatology; Scleroderma, Systemic; Selective Serotonin Reuptake Inhibitors; Ulcer

To determine the effect of riociguat, an oral, selective soluble guanylate cyclase stimulator, on the net digital ulcer (DU) burden in systemic sclerosis (SSc).. Participants with SSc-related active or painful indeterminate DUs were recruited in a multicenter, double-blind, randomized, placebo-controlled, proof-of-concept trial. Eligible participants were required to have at least one visible, active ischemic DU or painful indeterminate DU at screening, located at or distal to the proximal interphalangeal joint and that developed or worsened within 8 weeks prior to screening. Participants were randomized 1:1 to placebo or riociguat in individualized doses (maximum of 2.5 mg three times daily) during an 8-week titration period, followed by an 8-week stable dosing period. This was followed by an optional 16-week open-label extension phase for participants with active DU/reoccurrence of DUs within 1 month of the end of the main treatment phase. The primary endpoint was the change from baseline to week 16 in net ulcer burden (NUB), analyzed using ANCOVA. Other endpoints included plasma biomarkers and proportion of participants with treatment-emergent adverse events (AEs).. Seventeen participants (eight placebo, nine riociguat) were randomized at five centers. Six participants in each group transitioned to the open-label extension. Baseline characteristics were comparable between the treatment groups, except participants randomized to placebo were older and had longer disease duration (p < 0.05). At baseline, the mean (SD) NUB was 2.5 (2.0) in the placebo and 2.4 (1.4) in the riociguat. No significant treatment difference was observed in the change from baseline to 16 weeks in NUB (adjusted mean treatment difference - 0.24, 95% CI (- 1.46, 0.99), p = 0.70). Four participants experienced five serious AE (four in riociguat and one in placebo); none was considered related to study medication. Statistically significant elevation of cGMP was observed at 16 weeks in the riociguat group (p = 0.05); no other biomarkers showed significant changes. In the open-label extension, participants in the riociguat-riociguat arm had complete healing of their DUs.. In participants with SSc-DU, treatment with riociguat did not reduce the number of DU net burden compared with placebo at 16 weeks. Open-label extension suggests that longer duration is needed to promote DU healing, which needs to be confirmed in a new trial.. ClinicalTrials.gov, NCT02915835 . Registered on September 27, 2016.

Topics: Adult; Dose-Response Relationship, Drug; Double-Blind Method; Enzyme Activators; Female; Finger Phalanges; Follow-Up Studies; Humans; Male; Middle Aged; Pilot Projects; Pyrazoles; Pyrimidines; Scleroderma, Systemic; Skin Ulcer; Treatment Outcome

The 12-week, phase III Pulmonary Arterial hyperTENsion sGC-stimulator Trial (PATENT)-1 study investigated riociguat in patients with pulmonary arterial hypertension (PAH). Here, we present a prospectively planned analysis of the safety and efficacy of riociguat in the subgroup of patients with PAH associated with connective tissue disease (PAH-CTD).. Patients with PAH-CTD were further classified post hoc as having PAH associated with systemic sclerosis or PAH-other defined CTD. In PATENT-1, patients received riociguat (maximum 2.5 or 1.5 mg three times daily) or placebo. Efficacy endpoints included change from baseline in 6-minute walking distance (6MWD; primary endpoint), haemodynamics and WHO functional class (WHO FC). In the long-term extension PATENT-2, patients received riociguat (maximum 2.5 mg three times daily); the primary endpoint was safety and tolerability.. In patients with PAH-CTD, riociguat increased mean 6MWD, WHO FC, pulmonary vascular resistance and cardiac index. Improvements in 6MWD and WHO FC persisted at 2 years. Two-year survival of patients with PAH-CTD was the same as for idiopathic PAH (93%). Riociguat had a similar safety profile in patients with PAH-CTD to that of the overall population.. Riociguat was well tolerated and associated with positive trends in 6MWD and other endpoints that were sustained at 2 years in patients with PAH-CTD.. PATENT-1 (NCT00810693), PATENT-2 (NCT00863681).

Topics: Adult; Aged; Antihypertensive Agents; Connective Tissue Diseases; Female; Humans; Hypertension, Pulmonary; Male; Middle Aged; Pyrazoles; Pyrimidines; Scleroderma, Systemic; Treatment Outcome; Vascular Resistance; Walk Test

RISE-SSc is a randomized, double-blind, placebo-controlled phase 2 study investigating the efficacy and safety of riociguat in patients with diffuse cutaneous systemic sclerosis (dcSSc). Based on positive results from riociguat trials in patients with pulmonary hypertension and chronic thromboembolic pulmonary hypertension in combination with the known antiproliferative and antifibrotic effects seen in animal models, patients with SSc may benefit from treatment with riociguat. Patients with SSc meeting the ACR/EULAR systemic sclerosis classification criteria with diffuse cutaneous SSc (dcSSc) subset per LeRoy criteria, and a disease duration of less than or equal to 18 months will be randomized to placebo or riociguat 0.5 mg (up-titrated to a maximum dose of 2.5 mg TID over 10 weeks) and maintained on therapy for a total of 52 weeks. During the first 10 weeks of the long-term extension phase, placebo subjects will be up-titrated on riociguat, and all patients will be followed for up to 6 years. The primary endpoint of change in modified Rodnan skin score (mRSS) from baseline will be assessed at 52 weeks, as will be secondary endpoints such as mRSS progression and regression rates, patient quality of life, digital ulcer burden, and change in forced vital capacity and carbon monoxide diffusing capacity. This review will further define the clinical rationale for the use of riociguat in the treatment of SSc and provide details on study protocol, design, and outcome reporting.. Clinicaltrials.gov identifier: NCT02283762.

Topics: Carbon Monoxide; Dose-Response Relationship, Drug; Double-Blind Method; Enzyme Activators; Female; Humans; Hypertension, Pulmonary; Male; Pulmonary Diffusing Capacity; Pulmonary Embolism; Pyrazoles; Pyrimidines; Quality of Life; Scleroderma, Diffuse; Scleroderma, Systemic; Skin; Skin Diseases; Soluble Guanylyl Cyclase; Treatment Outcome; Vital Capacity

Topics: Humans; Pyrazoles; Pyrimidines; Scleroderma, Systemic

Topics: Humans; Pyrazoles; Pyrimidines; Scleroderma, Systemic

Stimulators of the soluble guanylate cyclase (sGC) have recently been shown to inhibit transforming growth factor-β signalling. Here, we aimed to demonstrate that riociguat, the drug candidate for clinical trials in systemic sclerosis (SSc), is effective in experimental fibrosis and to compare its efficacy to that of phosphodiesterase V inhibitors that also increase the intracellular levels of cyclic guanosine monophosphate.. The antifibrotic effects of riociguat and sildenafil were compared in the tight-skin 1 model, in bleomycin-induced fibrosis and in a model of sclerodermatous chronic graft-versus-host-disease (cGvHD). Doses of 0.1-3 mg/kg twice a day for riociguat and of 3-10 mg/kg twice a day for sildenafil were used.. Riociguat dose-dependently reduced skin thickening, myofibroblast differentiation and accumulation of collagen with potent antifibrotic effects at 1 and 3 mg/kg. Riociguat also ameliorated fibrosis of the gastrointestinal tract in the cGvHD model. The antifibrotic effects were associated with reduced phosphorylation of extracellular signal-regulated kinases. Sildenafil at doses of 3 and 10 mg/kg exerted mild antifibrotic effects that were significantly less pronounced compared with 1 and 3 mg/kg riociguat.. These data demonstrated potent antifibrotic effects of riociguat on experimental skin and organ fibrosis. These findings suggest a role for riociguat for the treatment of fibrotic diseases, especially for the treatment of SSc. A phase II study with riociguat in patients with SSc is currently starting.

Topics: Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Fibrosis; Guanylate Cyclase; Mice; Mice, Inbred Strains; Phosphodiesterase 5 Inhibitors; Pyrazoles; Pyrimidines; Scleroderma, Systemic; Sildenafil Citrate; Skin

Topics: Algorithms; Animals; Antibodies, Monoclonal, Murine-Derived; Antineoplastic Agents; Endothelin Receptor Antagonists; Guanylate Cyclase; Humans; Hypertension, Pulmonary; Indoles; Pulmonary Artery; Pyrazoles; Pyridones; Pyrimidines; Rituximab; Scleroderma, Systemic; Sulfonamides