NEW YORK (AP) -- Idenix Pharmaceuticals Inc. said Thursday the Food and Drug Administration wants more safety data on its experimental hepatitis C drug IDX20963 before it will allow the company to begin human testing.
The company's shares plunged $1.39, or 27 percent, to $3.75 in aftermarket trading following the announcement.
Idenix said clinical trials are on hold until it addresses the FDA's concerns. The company did not say how long it believes clinical testing for IDX20963 might be delayed by the request for more preclinical data.
The Cambridge, Mass., company does not have any approved products. Idenix is running mid-stage clinical trials of another hepatitis C drug, IDX719, and is running preclinical trials of other potential drugs.
Shares of Idenix fell 3 percent to $5.13 Thursday as the broader markets slumped during the regular trading session.