NIH stops study in sickle-cell patients

WASHINGTON (AP) — The government has stopped a study of a potential treatment for certain sickle-cell disease sufferers a year early because of a big increase in serious side effects.

At issue is whether the same ingredient that powers the impotence pill Viagra could treat a leading killer of sickle-cell patients, a kind of lung damage called pulmonary hypertension.

A particular dose of sildenafil, sold under the brand name Revatio, is approved to treat general pulmonary hypertension, but not in sickle-cell patients, because doctors didn’t know how it would react in them.

The National Institutes of Health was sponsoring a study at nine U.S. hospitals and one in London to try to answer that question.

An early safety review found more than a third of sildenafil users had serious side effects compared with 8 percent of patients given a dummy pill, the NIH announced Tuesday.