GlaxoSmithKline (GSK) recently announced it has applied for a European Medicines Agency (EMA) variation to the Marketing Authorization for ambrisentan (Volibris®), in order to expand the currently approved indication to include its use as a first-line combination therapy with tadalafil for pulmonary arterial hypertension (PAH). Ambrisentan is classified as a selective endothelin type-A receptor antagonist, which was previously approved in the European Union (EU) as a treatment for PAH classified as WHO functional class II and III to enhance tolerance for physical activity.
Pulmonary arterial hypertension is estimated to affect about 200,000 patients throughout the world. It is a life-threatening cardiopulmonary condition that tends to be misdiagnosed as COPD based on its early, non-distinct symptoms before it irreversibly progresses to right-side congestion and failure. Research has yet to find a cure, therefore treatment focuses on relieving symptoms in order to improve and maintain quality of life.
GSK’s recent EMA application for an extended indication is supported by encouraging findings from a Phase IIIb/IV study, dubbed AMBITION, which was carried out in partnership with Gilead Sciences, Inc. The study examined the efficacy of treating naive adult PAH patients showing WHO functional class II and III symptoms with a combination therapy of ambrisentan and tadalafil.
According to Dr. Carlo Russo, GSK’s Senior Vice President and Head of GSK Rare Diseases Research & Development, the AMBITION study’s results demonstrated the combination therapy’s superior efficacy over traditional, first-line monotherapy with either ambrisentan or tadalafil alone. “This submission has been part of our efforts to continue to help patients with pulmonary arterial hypertension and we look forward to the outcome.”
GSK is also preparing regulatory submissions to other international territories for the extended therapeutic indication of ambrisentan (Volibris®) as a combination therapy.
Pulmonary hypertension is one of the more common, serious complications of a rare autoimmune disease called scleroderma. Bayer is currently funding a long-term clinical trial for patients with PAH secondary to scleroderma to examine the efficacy, safety, and tolerability profile of inhaled Ventavis (iloprost, also known as BAYQ6256). Participants can have either idiopathic or hereditary PAH for up to 4 years. Enrolment is ongoing.