Viagra For Hypertension Trial Halted

Drug Made By Pfizer

Viva Viagra, is the memorable advertising slogan for the erectile dysfunction (ED) drug.  The drug, made by Pfizer and called sildenafil, is also used to treat pulmonary hypertension by relaxing the blood vessels in the lungs.

But serious concern was being given by researchers to see if Viagra could be used to treat pulmonary hypertension in those suffering with sickle cell disease.   It is already approved under the brand name of Revatio, (Pfizer) for use in patients with pulmonary hypertension without sickle cell disease. That condition causes high blood pressure inside the arteries carrying blood to the lungs and can lead to heart failure and death.   Relaxing blood vessels allows the blood to flow more easily. 

About one-third of those who have sickle cell disease also go on to develop pulmonary hypertension. 

But now the National Institutes of Health (NIH) has stopped a drug trial after it was found that the drug caused serious medical problems in sickle cell patients.   In all, 74 patients were enrolled. All had sickle cell disease and mild to severe pulmonary hypertension, according to the NIH.

The researchers found that among patients taking Revatio, 38 percent had effects such as sickle cell “crises” compared to eight percent taking the placebo. Painful crisis are the leading cause of emergency room visits among people suffering from sickle cell anemia and can include life-threatening complications such as acute chest syndrome, stroke, and complications from infections.

No deaths were reported.

NIH director, Dr. Elizabeth Nabel, tells Reuters,  "In the meantime, we encourage patients with sickle cell disease who are taking sildenafil for pulmonary hypertension to talk with their physicians about the potential risks and benefits of the medication and what actions they should consider, including whether to taper off this medication and how to best manage both sickle cell disease and pulmonary hypertension."

Sildenafil is approved by the Food and Drug Administration for patients who have pulmonary hypertension.  The FDA was notified of the drug trial termination on July 14.

An estimated 70,000 to 100,000 people in the U.S. have sickle cell disease. It is found primarily in the African-American population and also to a lesser degree, among people whose families are from South or Central America.    #