FDA lung experts back InterMune drug for rare lung disease, despite efficacy questions

FDA panel favors approval for InterMune drug

WASHINGTON — Federal health advisers on Tuesday voted in favor of an experimental drug from InterMune Inc., despite mixed evidence of whether it provides significant benefits for patients with a rare lung disease.

The Food and Drug Administration’s panel of lung experts voted 9-3 to recommend approval of the company’s drug pirfenidone. That recommendation followed a narrower 7-5 vote that the drug provides a “clinically meaningful benefit” for patients with idiopathic pulmonary fibrosis, an often fatal lung disease for which there are no approved drugs.

The FDA is not required to follow the group’s advice, though it often does. The agency is scheduled to make its final decision by May 4.

Ultimately, the lack of options for patients with idiopathic pulmonary fibrosis, or IPF, appeared to sway a majority of panelists in the drug’s favor.

“IPF is a fatal disease and you have to offer your patients hope,” said Karen Gottesman, the panel’s patient representative. “If this drug can offer your patients even a smidgen of hope, it’s worth approving.”

Intermune submitted two studies for its drug to FDA, measuring ability to improve lung function in patients. While one study showed a statistically significant 4.4 percent increase in lung strength, another failed to achieve significance compared with placebo.

The FDA usually requires two placebo-controlled trials showing meaningful results to grant approval, a fact cited by several panelists who voted against the drug’s benefits.

“We have two competing studies here,” said Dr. Peter Terry, of Johns Hopkins University Medical Institutions. “Based on the agency’s requirement for substantial evidence I don’t think this meets the criteria for clinically meaningful benefit.”

Most panelists agreed the drug’s effect was modest and that long-term follow-up would be needed to determine whether it can extend patient survival. While slightly more patients taking pirfenidone survived compared with patients taking placebo, there wasn’t an overall survival benefit in the company’s studies, according to the FDA.

“Some people were expecting a cure, this is not a cure,” said Dr. Richard Honsinger, of Los Alamos Medical Center. “This drug just slows the decline caused by the disease.”

In a separate vote, panelists ruled 9-3 that pirfenidone was safe for patients. Most panelists said side effects such as nausea, rash and fatigue were tolerable, considering the fatal nature of the disease.

While some pirfenidone patients experienced abnormalities in liver function, those issues mostly resolved after patients discontinued the drug.

About 200,000 people in the U.S. and Europe have idiopathic pulmonary fibrosis. The disease causes scarring and stiffening of the lungs, which makes it increasingly difficult to breathe over time. The cause of the disease is unknown.

Intermune Chief Medical Officer, Dr. Steven Porter said he was “very excited,” by the meeting’s outcome.

“I think it was a very productive discussion and the data spoke for itself,” said Porter.

If approved, InterMune plans to market the drug in the U.S. under the name Esbriet. The drug was approved in Japan in October 2008, where it is sold under the name Pirespa by Shionogi and Co.

Shares of the Brisbane, Calif.-based company were halted in trading Tuesday ahead of the FDA’s meeting. The stock closed at $23.30 Monday.

Last week shares jumped to their highest point since 2007 after the FDA posted its review of pirfenidone.