Elan Corp. plc and American Cyanamid Co. have filed a patentsuit against Alza Corp. and Marion Merrell Dow Inc., alleginginfringement of U.S. patent No. 4,943,435 relating to atransdermal nicotine system.

The patent, which was issued to Menlo Park, Calif.-basedPharmetrix Corp., was assigned to Elan of Athlone, Ireland.According to an announcement by Alza and MMD, Elan and itslicensee, American Cyanamid of Wayne, N.J., filed the suit inU.S. District Court in San Francisco on Wednesday.

Earlier this month, the Food and Drug Administration grantedmarketing approval for Alza's Nicoderm patch. Marion MerrellDow Inc., Alza's marketing partner, had said it would beginselling Nicoderm before the end of the year. That's now up inthe air.

At a hearing on Thursday, the court set a Dec. 2 hearing date toact on a request for a preliminary injunction against Alza andMMD. The court also ordered that none of the parties commentpublicly and that no sales of Nicoderm take place prior to thehearing.

Elan in May sued Cygnus Therapeutic Systems Inc. of RedwoodCity, Calif., which has licensed its nicotine patch to KabiPharmacia. Kabi granted U.S. marketing rights to the patch,which is not yet being marketed, to Warner-Lambert.

"We filed for summary judgment on the grounds that we're notinfringing," said Shirley Clayton, Cygnus' vice president offinance. That motion hasn't been heard yet.

"Elan's claims are very broad, including the transdermaldelivery of nicotine for smoking cessation," said Clayton. "Butpeople have known for many years that nicotine goes throughthe skin. So our position is there's a lot of prior art thatinvalidates the broad claim." Cygnus has issued patents relatingto the manufacture of its patch and its composition.

Ciba-Geigy is also developing a nicotine patch.

Alza's announcement came after the market closed. Its stock(AMEX:AZA) picked up $1.88, closing at $79.38. On Wednesday,the company announced an agreement with American HomeProducts Corp. to develop generic pharmaceuticals using Alza'sproprietary drug delivery systems. -- Karen Bernstein

(c) 1997 American Health Consultants. All rights reserved.