FDA Approves Bayer's Adempas to Treat Pulmonary Hypertension in Adults

October 8, 2013—Bayer HealthCare (Whippany, NJ) announced that the US Food and Drug Administration (FDA) has approved the company's Adempas (riociguat) tablets for the treatment of adults with persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH; World Health Organization [WHO] group 4) after surgical treatment or inoperable CTEPH to improve exercise capacity and WHO functional class; and also for the treatment of adults with pulmonary arterial hypertension (PAH; WHO group 1) to improve exercise capacity, improve WHO functional class, and delay clinical worsening.

On September 23, Bayer announced that Health Canada approved the drug for the treatment of inoperable or persistent/recurrent CTEPH after surgery in adult patients with WHO functional class II or III pulmonary hypertension. On September 26, Bayer announced that the FDA's Office of Orphan Products Development granted two separate orphan drug designations for riociguat for the treatment of PAH and chronic CTEPH. The Orphan Drug Designation program provides orphan status to drugs and biologics that are defined as those intended for the safe and effective treatment, diagnosis, or prevention of rare diseases and disorders.

Bayer stated that Adempas (riociguat, BAY 63-2521), a stimulator of soluble guanylate cyclase (sGC), represents a new class of drug now available in the United States. Pulmonary hypertension is associated with endothelial dysfunction, impaired synthesis of nitric oxide (NO), and insufficient stimulation of the NO-sGC-cGMP pathway. Riociguat sensitizes sGC to endogenous NO by stabilizing the NO-sGC binding. Riociguat also directly stimulates sGC via a different binding site independently of NO. Riociguat restores the NO-sGC-cGMP pathway and leads to increased generation of cGMP with subsequent vasodilation

Riociguat is contraindicated for pregnancy. For all female patients, riociguat is available only through a restricted program called the Adempas Risk Evaluation and Mitigation Strategy program, which can be accessed online at www.AdempasREMS.com or by phone at 1-855-4ADEMPAS. Additionally, riociguat is not recommended for patients with pulmonary veno-occlusive disease because pulmonary vasodilators may significantly worsen the cardiovascular status of these patients. Complete adverse reaction and other safety information can be obtained online at www.adempas-us.com. Bayer also noted that it offers patient assistance through the Adempas Aim Support Center program.

According to the company, the drug's efficacy for PAH was shown in patients on riociguat monotherapy or in combination with endothelin receptor antagonists (ERAs) or prostanoids (inhaled, oral, or subcutaneous). Studies establishing effectiveness included predominately patients with WHO functional class II-III and etiologies of idiopathic or heritable PAH (61%) or PAH associated with connective tissue diseases (25%).

"CTEPH and PAH are serious and life-threatening diseases," commented Nick H. Kim, MD, in Bayer's press release. “The approval of Adempas equips physicians with a new approach to treating PAH patients, and it gives us the first approved drug treatment for patients with inoperable CTEPH or with persistent/recurrent CTEPH after surgery. While surgery should always be considered as the first treatment option for CTEPH, the fact remains that up to 40% of CTEPH patients are not eligible for surgery, and 10 to 35% of CTEPH patients have disease that persists after surgery.” Dr. Kim is Associate Clinical Professor of Medicine, Division of Pulmonary and Critical Care Medicine; Director, Pulmonary Vascular Medicine; and Director, Fellowship Program at the University of California San Diego.

Also in Bayer's announcement, Rino Aldrighetti, President and Chief Executive Officer of the Pulmonary Hypertension Association, stated, “From a patient's perspective, living with pulmonary hypertension remains difficult. We know that not all treatments work for all people. We get excited when there is a new treatment option for PAH patients, and we are thrilled there is finally an approved drug treatment for people living with persistent/recurrent CTEPH after surgical treatment or inoperable CTEPH.”