By Toni Clarke
Aug 2 Bayer AG's experimental drug to
treat two types of pulmonary hypertension worked well in
clinical trials and should be approved, but at lower doses than
those proposed by the company, according to medical reviewers at
the U.S. Food and Drug Administration.
The reviewers posted their report on the agency's website in
preparation for a meeting on Tuesday of outside medical experts
who will make their own recommendation on whether the FDA should
approve the drug, riociguat.
If approved, the drug would be sold under the brand name
Adempas. It is designed to improve the ability of patients with
chronic thromboembolic pulmonary hypertension to exercise. The
disease can be caused by old blood clots in the lungs and can
lead to shortness of breath, chest pain and heart palpitations.
The drug is also being developed to improve exercise ability
in patients with pulmonary arterial hypertension. Pulmonary
arteries carry blood from the heart to the lungs. In patients
with PAH the arteries constrict, forcing the heart to work
faster and blood pressure within the lungs to rise.
If approved, the drug is expected to generate sales of $610
million, according to the average estimate of six analysts
polled by Thomson Reuters.
The primary safety concerns raised by the reviewers relate
to bleeding, low blood pressure and possible impact on kidney
function in some patients. The reviewers said the drug can cause
birth defects and a risk-management program would need to be