FDA delays indiplon, Neurocrine drops 62%

The US Food and Drug Administration says it will not approve the extended release tablet form of Neurocrine Biosciences' insomnia drug, indiplon, causing shares in the San Diego-headquartered firm to nose dive 62% since May 15, the day of the announcement.

The agency approved 5mg and 10mg capsules strengths of indiplon, which is being developed with world drugs giant Pfizer, but delayed the clearance of the 15mg extended-release formulation. Neurocrine says that the FDA indicated that they did not have an opportunity to review all of the information submitted during the New Drug Application review cycles, adding that it will meet with the agency to discuss the next steps towards approval. Indiplon XR was seen by many indsutry observers as the only way for the firm to compete in the $3.0 billion a year US sleeping pill market. On the day of the news, shares in Sanofi-Aventis, maker of rival drug Ambien (zolpidem tartrate), rose 2.8%.