Idenix Says FDA Put Studies Of Hepatitis C Drug On Hold

Idenix Pharmaceuticals Inc. (IDIX) was verbally notified by the U.S. Food and Drug Administration that its drug programs to treat the virus that causes hepatitis C are on hold.

The biopharmaceutical company said the delay came after Idenix notified the U.S. regulator of three instances of elevated liver function related to a drug-interaction study related to two of its drug compounds. The three patients liver function tests returned to nearly normal levels during follow-up, the company said.

Chairman and Chief Executive Jean-Pierre Sommadossi said, "We have not yet received a formal letter from the FDA, nor has the agency had an opportunity to review the safety and efficacy data from recently completed clinical trials."

Idenix will submit data to the FDA from recently completed trials, including toxicology, proof of concept and drug-interaction studies to assess the next steps in the development of the treatments.

The company plans to work closely with independent experts and an external safety committee to determine the cause of the liver issues.

Shares closed Friday at $5.99 and were inactive premarket. Markets were closed Monday for Labor Day. The stock has nearly tripled this year amid favorable interim results in January and April related to the drug.

-By Tess Stynes, Dow Jones Newswires; 212-416-2481; [e-mail]