Berlex Laboratories has opened another front in its campaign to block competition from Biogen Inc.'s Avonex beta interferon for multiple sclerosis, accusing BGEN of patent infringement in a federal court suit.

The action, filed in U.S. District Court in New Jersey, alleges that BGEN is willfully infringing Berlex's McCormick patent - U.S. No. 5,376,567. The patent, which does not pertain to Berlex's Betaseron product, is alleged to cover methods used to produce Avonex.

BGEN had anticipated the move, filing suit more than two months ago in U.S. District Court in Massachusetts for a declaratory judgement that the McCormick patent is invalid and that BGEN does not infringe it in any case. "We knew they were going to do this so we filed to invalidate their patent on May 3," said BGEN spokesperson Richard Lundberg.

Second shoe drops

This is the second shoe that