selexipag and macitentan

Pulmonary arterial hypertension (PAH) was previously considered a uniformly fatal disease, with patients succumbing to right heart failure and death at an average of 3 years after diagnosis. The past 20 years, however, have seen the development of numerous targeted therapies that have changed the natural history of PAH. As more pharmacologic agents have been approved and utilized, further advances in the design of and endpoints for clinical trials. This study will review some of these notable developments.. The successful design and completion of long-term, event-driven trials is exemplified in three recent studies: SERAPHIN, GRIPHON, and AMBITION. SERAPHIN and GRIPHON evaluated the newer agents, macitentan, an endothelin receptor antagonist, and selexipag, a prostacyclin receptor agonist, respectively. Both trials were large-scale studies that, in addition to showing marked effect on the primary endpoint of morbidity/mortality, clearly demonstrated that assessment of long-term effects of PAH therapies is feasible for new compounds. The AMBITION study evaluated a treatment strategy, namely up-front combination therapy with tadalafil and ambrisentan compared with monotherapy and showed the combination approach to be superior at decreasing the likelihood of clinical failure.. The evolution of clinical trials in PAH has direct implications for care of these patients. The short and long-term benefits of combination regimens suggest that the multidrug approach to PAH should, in fact, be standard of care for this disease.

Topics: Acetamides; Antihypertensive Agents; Clinical Trials as Topic; Endothelin Receptor Antagonists; Humans; Hypertension, Pulmonary; Inositol 1,4,5-Trisphosphate Receptors; Phenylpropionates; Phosphodiesterase 5 Inhibitors; Pyrazines; Pyridazines; Pyrimidines; Randomized Controlled Trials as Topic; Sulfonamides

In recent years, there have been major changes in the landscape of pulmonary arterial hypertension therapy with the introduction of novel agents and innovative treatment strategies for this progressive disease. The aim of this review is to discuss the evolution in trial design in this field and highlight the salient features of recently published studies. We also summarize our approach to therapy selection in this chronic disease and identify areas for future exploration. The therapeutic armamentarium now includes 13 approved therapies. While most of these agents have been studied in small, short-term trials using the 6-min walk distance as a primary endpoint, there has been a shift in recent years toward larger, long-term, event-driven trials that utilize combined morbidity and mortality endpoints. The SERAPHIN and GRIPHON trials were two such studies, which led to the approval of the dual endothelin-receptor antagonist macitentan and the selective prostacyclin receptor antagonist selexipag, respectively. Other event-driven trials, like AMBITION and COMPASS-2, have provided valuable insight into the use of combined oral therapies in symptomatic patients. In conclusion, despite being a more manageable disease in the modern treatment era, pulmonary hypertension is still associated with considerable morbidity and much more work remains to be done in this field. Important questions remain about the most optimal way to manage patients and conduct trials going forward.

Topics: Acetamides; Antihypertensive Agents; Endothelin Receptor Antagonists; Humans; Hypertension, Pulmonary; Pyrazines; Pyrimidines; Sulfonamides

Pulmonary arterial hypertension (PAH) is a rare disease with a poor prognosis if not treated. Pharmacological treatment options for PAH have increased significantly over the past 10 years, with availability of intravenous, oral and inhaled drugs targeting the nitric oxide, endothelin and prostacyclin pathways. Treatment with these therapies in specialised pulmonary hypertension centres has resulted in reductions in patient symptoms, disease progression and mortality, and improved exercise capacity. Recognition of chronic thromboembolic pulmonary hypertension is important, as this cause of pulmonary hypertension may be amenable to surgical treatment. Several new oral drugs, including macitentan, riociguat and selexipag, some of which have novel modes of action, and the use of combinations of PAH drugs have recently been shown to be beneficial in treating PAH and are likely to change treatment for this condition in the future.

Topics: Acetamides; Antihypertensive Agents; Australia; Drug Therapy, Combination; Humans; Hypertension, Pulmonary; Pyrazines; Pyrazoles; Pyrimidines; Sulfonamides; World Health Organization

It is well established that the endothelin, nitric oxide and prostacyclin pathways play an important role in the development of pulmonary arterial hypertension (PAH). Indeed, the therapeutic options currently available for the management of PAH all act on one of these mechanistic pathways. However, this is an exciting time for both clinicians and scientists, as increased understanding of the mechanisms involved in the pathogenesis and progression of PAH has resulted in the development of a number of novel therapeutic options. This article highlights how the introduction of new compounds such as macitentan, riociguat and selexipag, which act on the endothelin, nitric oxide and prostacyclin pathways, respectively, have the potential to further improve the prognosis for patients with PAH.

Topics: Acetamides; Animals; Antihypertensive Agents; Benzamides; Clinical Trials as Topic; Drugs, Investigational; Endothelin A Receptor Antagonists; Endothelin B Receptor Antagonists; Endothelin-1; Epoprostenol; Guanylate Cyclase; Humans; Hypertension, Pulmonary; Imatinib Mesylate; Lisuride; Nitric Oxide; Phosphodiesterase 5 Inhibitors; Piperazines; Protein Kinase Inhibitors; Pyrazines; Pyrazoles; Pyrimidines; Serotonin Antagonists; Sulfonamides

In pulmonary arterial hypertension (PAH), there are no data comparing initial triple oral therapy with initial double oral therapy.. TRITON (The Efficacy and Safety of Initial Triple Versus Initial Dual Oral Combination Therapy in Patients With Newly Diagnosed Pulmonary Arterial Hypertension; NCT02558231), a multicenter, double-blind, randomized phase 3b study, evaluated initial triple (macitentan, tadalafil, and selexipag) versus initial double (macitentan, tadalafil, and placebo) oral therapy in newly diagnosed, treatment-naive patients with PAH.. Efficacy was assessed until the last patient randomized completed week 26 (end of main observation period). The primary endpoint was change in pulmonary vascular resistance (PVR) at week 26.. Patients were assigned to initial triple (n = 123) or initial double therapy (n = 124). At week 26, both treatment strategies reduced PVR compared with baseline (by 54% and 52%), with no significant difference between groups (ratio of geometric means: 0.96; 95% confidence interval: 0.86-1.07; P = 0.42). Six-minute walk distance and N-terminal pro-brain natriuretic peptide improved by week 26, with no difference between groups. Risk for disease progression (to end of main observation period) was reduced with initial triple versus initial double therapy (hazard ratio: 0.59; 95% confidence interval: 0.32-1.09). Most common adverse events with initial triple therapy included headache, diarrhea, and nausea. By the end of the main observation period, 2 patients in the initial triple and 9 in the initial double therapy groups had died.. In patients with newly diagnosed PAH, both treatment strategies markedly reduced PVR by week 26, with no significant difference between groups (primary endpoint not met). Exploratory analyses suggested a possible signal for improved long-term outcomes with initial triple versus initial double oral therapy.

Topics: Acetamides; Adult; Aged; Antihypertensive Agents; Double-Blind Method; Drug Therapy, Combination; Endothelin Receptor Antagonists; Female; Humans; Male; Middle Aged; Phosphodiesterase 5 Inhibitors; Pulmonary Arterial Hypertension; Pyrazines; Pyrimidines; Sulfonamides; Tadalafil

Topics: Acetamides; Adult; Aged; Antihypertensive Agents; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Follow-Up Studies; Humans; Male; Middle Aged; Pulmonary Arterial Hypertension; Pyrazines; Pyrimidines; Severity of Illness Index; Sulfonamides; Tadalafil; Treatment Outcome; Vascular Resistance

Pulmonary arterial hypertension is a progressive, debilitating condition characterized by increased resistance in the pulmonary arterial circulation. Current treatments for pulmonary arterial hypertension include endothelin receptor antagonists such as bosentan, sitaxentan, ambrisentan, macitentan, and oral prostacyclin receptor agonists such as selexipag. Endothelin receptor antagonists have been associated with liver injury, while hepatotoxicity was not reported for selexipag. Although genetic variability has been indisputably associated with variability in drug response, no study has been designed until now to assess its effects on the pharmacokinetics of endothelin receptor antagonists or selexipag.. We report the case of a 58-year-old female Caucasian patient with a dramatic increase in plasma levels of transaminases after treatment with macitentan and selexipag, drugs whose risk of causing liver injury has so far been considered limited. After therapy discontinuation, plasma levels of transaminases returned to baseline, thus suggesting a role of these drugs in the observed hepatotoxicity. After pharmacological counseling, we decided to introduce ambrisentan for the patient's treatment. After 7 months of treatment, no liver injury has been reported. To evaluate the role of genetic factors in the observed hepatotoxicity, we genotyped the patient for single-nucleotide polymorphisms previously associated with macitentan, ambrisentan, or selexipag metabolism. We found a genetic profile associated with a poor metabolizer (PM) phenotype for CYP2C8 and CYP2C9, key enzymes for elimination of both macitentan and selexipag. The reported results suggest that an allelic profile associated with low activity for CYP2C8 and CYP2C9 enzyme could be a potential risk factor for macitentan and selexipag-induced liver injury and could provide a possible marker for early identification of subjects at higher risk of developing hepatotoxicity.. A multidisciplinary approach based on clinical evaluation, as well as pharmacological counseling and evaluation of the patient's genetic profile, might be useful for identification of patients with a high chance of drug-induced liver injury, avoiding unnecessary risks in therapy selection and prescription.

Topics: Bosentan; Counseling; Cytochrome P-450 CYP2C8; Cytochrome P-450 CYP2C9; Endothelin Receptor Antagonists; Familial Primary Pulmonary Hypertension; Female; Humans; Hypertension, Pulmonary; Middle Aged; Pulmonary Arterial Hypertension; Receptors, Epoprostenol; Transaminases

The article presents a clinical case of successful triple combination therapy in a female patient with functional class III idiopathic pulmonary arterial hypertension. Supplementing the previous macitentan and riociguat treatment with selexipag reduced the severity of clinical manifestations of pulmonary hypertension. Also, the treatment efficacy was demonstrated by improvement of laboratory and instrumental indexes. Time-related changes were evaluated at 3 months after initiation of the selexipag treatment.

Topics: Acetamides; Antihypertensive Agents; Familial Primary Pulmonary Hypertension; Female; Humans; Pyrazines; Pyrazoles; Pyrimidines; Sulfonamides

In this report, we describe the first successful case of transition from subcutaneous administration of treprostinil to selexipag in a patient with severe pulmonary arterial hypertension (PAH), by evaluating hemodynamic changes and exercise tolerance.. A 38-year-old female with idiopathic PAH (IPAH) had received initial triple combination therapy (macitentan PO, tadalafil PO, and treprostinil SC) and achieved excellent improvement in hemodynamics. Afterwards, due to the development of side effects from subcutaneous administration, we replaced treprostinil therapy with oral selexipag, resulting in stable hemodynamic parameters and exercise capacities.. We report the first case of successful replacement of treprostinil (20.1 ng/kg/min) with selexipag (1600 μg BID) as a component of triple combination therapy, which provides incentive to perform a larger, prospective exchange study.

Topics: Acetamides; Adult; Antihypertensive Agents; Drug Therapy, Combination; Epoprostenol; Exercise Tolerance; Familial Primary Pulmonary Hypertension; Female; Hemodynamics; Humans; Prospective Studies; Pyrazines; Pyrimidines; Sulfonamides

Topics: Acetamides; Administration, Oral; Antihypertensive Agents; Benzamides; Drug Therapy, Combination; Early Medical Intervention; Epoprostenol; Humans; Hypertension, Pulmonary; Imatinib Mesylate; Piperazines; Pyrazines; Pyrazoles; Pyrimidines; Randomized Controlled Trials as Topic; Sulfonamides