* FDA advisers vote 9-3 to back drug
* Final FDA decision expected by May 4
* Shares rise 63 percent after hours (Adds comments from panel member, company)
By Susan Heavey
SILVER SPRING, Md., March 9 (Reuters) - U.S. medical advisers backed InterMune Inc’s ITMN.O experimental drug to treat lung scarring on Tuesday, saying it should be approved for patients with the rare fatal condition, and the shares rose 63 percent in after-hours trading.
In a 9-3 vote, the Food and Drug Administration’s outside experts said the company’s data were strong enough to support use of the drug, pirfenidone, for patients with idiopathic pulmonary fibrosis (IPF).
“It’s not a perfect therapeutic intervention, but it helps fill the void,” said panelist Dr. Michael Foggs, a Chicago-based physician.
InterMune shares rose 63 percent in after-hours trading to $38 on Tuesday after being halted during normal trading hours while the advisory panel met. The shares closed Monday at $23.30 on Nasdaq.
On March 5 after the FDA released documents related to Tuesday’s meeting, InterMune’s shares rose nearly 80 percent in premarket trading. The shares reached a year high of $25.37 that day. They traded at $10.48 on Nov. 27.
InterMune is seeking FDA approval of pirfenidone to help mitigate worsening lung function in patients with IPF, in which the lungs scar with no apparent cause.
Analysts have said the drug’s approval could be key for the company, making it a possible takeover target.
The FDA will weigh the panel’s recommendation and is expected to make a final decision by May 4. The agency usually approves drugs that win advisory panel support.
The panel was more divided over how well pirfenidone worked than over potential side effects. Members voted 7-5 that InterMune’s data provided “substantial evidence” of a meaningful benefit.
Jerry Krishnan, a panelist who voted against approval, echoed others in stating that the drug appeared to work in certain patients but it was not clear who might benefit from treatment.
“I worry a little bit about potentially opening the possibility of widespread use” that could expose the larger population of IPF patients to risks without benefits, said Krishnan, a medical professor at the University of Chicago.
Panelists, including those who backed the drug, called for a patient registry to collect more data.
FDA reviewers had expressed concern that just one of InterMune’s two clinical trials showed any benefit while more pirfenidone than placebo patients dropped out over possible complications. Problems seen in the study included gastrointestinal issues, liver abnormalities and rash.
The committee voted 9-3 that InterMune adequately assessed the drug’s safety.
Representatives for the biotech company told the panel that pirfenidone was the only tested option for patients with IPF and that it could help improve patients’ quality of life.
“Pirfenidone did not cure IPF,” said Paul Noble, a medical professor at Duke University who spoke on behalf of InterMune. But, he said, it was “an important first step in IPF treatment.”
Roughly 90,000 to 100,000 Americans have IPF and currently either go untreated or use risky, unapproved therapies, company officials said.
InterMune’s Chief Medical Officer Steven Porter told the panel that complications were manageable by lowering the dose or stopping use of the drug.
InterMune said in a statement that it welcomed the panel vote and would work with the FDA. The company is planning a 5 p.m. teleconference to discuss the meeting.
InterMune has proposed selling the drug under the brand name Esbriet. (Reporting by Susan Heavey; Editing by Gary Hill)