FDA Gives Green Signal to Adempas to Treat Pulmonary Hypertension

The U.S. Food and Drug Administration has given the green signal to Adempas marketed by Bayer to treat pulmonary hypertension.

The U.S. FDA panel voted in favor of the drug Adempas (riociguat) to treat adults with two forms of pulmonary hypertension namely 'thromboembolic pulmonary hypertension' and 'pulmonary arterial hypertension'.  

 Pulmonary hypertension is a chronic, progressive, debilitating disease that occurs due to abnormal high blood pressure in the arteries of the lungs. It increases the workload in the right side of the heart and generally causes right heart failure. It often leads to death or requires lung transplantation. Thromboembolic pulmonary hypertension occurs due to blood clots that limit the flow of blood from the heart to the lungs. In pulmonary arterial hypertension, the arteries of the lungs narrow forcing the heart to function harder. Common symptoms include fatigue, shortness of breath, swelling of ankle and feet, fainting, and coughing up blood.

Belonging to the class of drugs called soluble guanylate cyclase stimulators, Adempas relaxes the arteries and increase the flow of blood and lowers the blood pressure. It is recommended for those people who suffer with chronic thromboembolic pulmonary hypertension (CTEPH) after surgery or patients who cannot undergo surgery, in order to improve their ability to exercise.

"Adempas is the first in its drug class approved to treat pulmonary hypertension and the first drug of any class to be shown to be effective for patients with CTEPH," Norman Stockbridge, M.D., Ph.D., director of the Division of Cardiovascular and Renal Drug Products in the FDA's Center for Drug Evaluation and Research, said in a press statement.

Based on a clinical trial conducted on 261 patients, the FDA panel checked the safety and effectiveness of the drug.  The participants were randomly given Adempas and they gradually increased the dose of the drug up to 2.5 mg three times daily, or they were given placebo three times daily. In this study they measured the distance a patient could walk in six minutes. After 16 days of treatment, they noticed that the average improvement in the 6 minute walk distance in those who were treated with Adempas was 46 meters more when compared to those who were treated with the placebo.

The safety and effectiveness of the drug to treat PAH was done on 443 participants who were randomly assigned to take Adempas 1.5 mg or 2.5 mg or placebo three times daily. After 12 weeks of treatment they noticed that there an average improvement in 6 minute walk distance by 36 meters in those treated with Adempas when compared to the placebo group.

The drug cannot be used by pregnant women as it harms the developing fetus. Females can take this drug only through Adempas REMS program. Common side effects of the drug include headache, dizziness, indigestion, nausea, vomiting, diarrhea and tissue swelling.