Wyeth fracture protein stumbles at FDA

Wyeth-Ayerst Laboratories, the pharmaceutical division of American HomeProducts, has received a not-approvable letter from the US Food and Drug Administration regarding the company's application to market rhBMP-2/ACS, a treatment for long-bone fractures utilizing a recombinant version of a naturally-occurring human protein that induces new bone growth.

Stryker Corp received a similar disappointment in the USA for OP-1 (osteogenic protein-1), a related product developed to treat non-union fractures of the tibia, earlier this year (Marketletter February 5).

The letter focuses on the design of the pivotal clinical study used in the dossier, as well as the interpretation of the clinical data submitted by the company, according to a Wyeth statement. The company said that it plans to meet with the FDA to discuss the agency's concerns, and stressed that this letter had no bearing on a separate filing for the drug, by Medtronic, as part of a medical device used for a spinal fusion application. rhBMP-1/ACS consists of recombinant human bone morphogenetic protein-2 applied directly to the fracture site using an absorbable collagen sponge carrier matrix.