GlaxoSmithKline and Pharmaceutical Resources Inc, through its subsidiary Par Pharmaceutical Inc, announced that Pentech Pharmaceuticals Inc and GSK have reached a settlement in their patent litigation over Pentech's proposed generic capsule version of GSK's anti-depressant Paxil (paroxetine hydrochloride). Pentech granted Par rights under Pentech's ANDA for paroxetine hydrochloride capsules.

The settlement will allow Par to distribute in Puerto Rico substitutable generic paroxetine hydrochloride immediate release tablets supplied and licensed from GSK for a royalty paid to GSK. Par will be entitled to distribute the same product in the U.S. market once another generic version fully substitutable for Paxil becomes available there.

In the settlement, Pentech and Par acknowledge that the GSK patent covering the hemihydrate form of paroxetine hydrochloride is valid and enforceable and would be infringed by Pentech's proposed capsule product, for which Pentech has applied for FDA approval. The same GSK patent was found valid and enforceable in a separate patent infringement case in Chicago against Apotex. Apotex was found not to infringe, and GSK is appealing that ruling.

The Federal Trade Commission's Bureau of Competition reviewed the settlement. The review was voluntary and was conducted at the request of GSK, Par and Pentech.

Following completion of the FTC review, GSK and Pentech submitted a motion for dismissal of the patent litigation by Judge Richard Posner in the U.S. District Court for the Northern District of Illinois (Chicago) in which the litigation has been pending since May 2000. The motion is pending. Distribution will begin in Puerto Rico when a dismissal order is entered.

The litigation and the settlement do not involve Paxil CR.