The U.S. Food and Drugs Administration (FDA) approved Bayer AG's Adempas, a drug for treating two types of pulmonary hypertension.
Adempas will treat chronic thromboembolic pulmonary hypertension (CTEPH), a form of hypertension caused by clots that prevent blood from flowing to the lungs. The drug will also be used to treat pulmonary arterial hypertension (PAH), another form of hypertension where the arteries of lungs constrict, making the heart work harder than normal. Symptoms of both forms are similar including short breath, weakness, fatigue and even heart failure.
"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," said 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.
In the first form of hypertension, Adempas will help people who cannot go into surgery to improve their ability to exercise. In the second case, the drug will also help to delay clinical worsening of their condition.
Adempas comes with a warning label, restricting use of the drug among pregnant women as it may harm the fetus. Patients can only receive the drug under an Adempas REMS program. For this, they must enrol in the program, comply with pregnancy testing requirements and be counseled on the need for contraception. Pharmacies will be allowed to sell the drug only to patients enrolled in the risk mitigation program.
Currently, the FDA recommends a dose limit of 2.5-milligrams. Initially the administration body had set the limit below 2.5 milligrams. However, upon Bayer's argument that a starting dose of 0.5 milligram and maximum dose of 1.5 milligrams three times a day would confer the same benefit as the higher dose with a reduced risk of side effects, the dose limit was increased. The FDA also left the dosage to the discretion of physicians.
The drug belongs to a class of drugs called soluble guanylate cyclase stimulators that help arteries relax to increase blood flow and decrease blood pressure. The side effects of Adempas include headache, dizziness, indigestion (dyspepsia), tissue swelling (peripheral edema), nausea, diarrhea and vomiting.
One in every three Americans suffers from hypertension. In certain forms, the disorder is chronic, progressive, debilitating, often leading to death or need for lung transplantation.
