The US FDA indicated Genelab Technologies Inc. that an additional, adequate, well-controlled phase III clinical trial would be necessary on its experimental drug Prestrata for women with systemic lupus erythematosus (SLE or lupus).

The company also discussed with the FDA its options for pursuing an indication of prevention of loss of bone mineral density (BMD) in women with lupus. Genelabs has pursued a BMD indication since receiving an approvable letter for its Prestara New Drug Application (NDA) in 2002. The FDA stated that additional positive prospective phase III clinical trial data would be necessary before the FDA would consider reviewing an NDA for BMD in lupus, states a Genelab release.

Based on the recent FDA interaction, Genelabs believes that pursuit of an indication for treating the signs and symptoms of lupus is a more viable route forward for Prestara than an indication for prevention of BMD loss in lupus.

"I am pleased that the FDA has provided guidance on their requirements for approval of Prestara for the treatment of lupus signs and symptoms. I believe the FDA recognises the need for new drugs for lupus, but at the same time they also must adhere to their established standards for approval. They are indicating that they will require one additional pivotal trial in order to approve our NDA for the treatment of lupus. Our next step is to determine the specifics of a new clinical trial evaluating the impact of Prestara on the overall signs and symptoms of lupus," stated James A.D. Smith, president and chief executive officer, Genelab.

Genelabs is presently in process of designing an additional clinical trial for Prestara for the treatment of lupus utilising the FDA guidance document published in 2005. The company plans to work with the FDA in the development of the protocol, as suggested by the FDA in the recent meeting, and plans to formally meet with the agency again regarding the prospective clinical trial design. Because the company currently does not have sufficient funds to conduct another clinical study of Prestara on its own, if an additional clinical trial is conducted it would likely be in conjunction with a new or existing collaborator, or, alternatively, Genelabs may have to delay or discontinue future development of Prestara, added the release.

Regarding approval for the treatment of lupus based on a single clinical trial, the FDA indicated that robust demonstration of efficacy would be required to be considered adequate evidence of efficacy.