GENERIC NIFEDIPINE: BARR FAILED TO PROVIDE PFIZER

GENERIC NIFEDIPINE: BARR FAILED TO PROVIDE PFIZER with information necessary to establish a claim of noninfringement, Pfizer maintains in a suit filed Sept. 27 in New York Federal Court. Barr filed an ANDA for nifedipine 10 and 20 mg capsules on Aug. 11, notifying Pfizer in a same-day letter. Pfizer claims that its nifedipine patent, which is licensed from Bayer A.G. and expires Jan. 8, 1991, is being infringed by Barr.

"In its Aug. 13 letter, Barr failed to provide a fully detailed statement of the factual and legal basis of its opinion that the '684 patent will not be infringed," the complaint states. "Barr alleged non-infringement of the '684 patent on unmeritorious grounds and also questioned the validity of certain claims of the '684 patent on unmeritorious grounds."

Barr is one of a number of drug firms being sued by Pfizer in connection with generic nifedipine products. Siegfried Pharmaceutical, Chase Chemical, Cord and Par are among the others. Previously, Barr was one of the first firms to receive ANDA approval of the first generic calcium channel blocker, verapamil.

"In its Aug. 11 letter, Barr referred to Bayer's U.S. patent, which expires Feb. 22, 1989 and broadly claims pharmaceutical compositions of nifedipine," Pfizer states in its complaint. "Barr stated that in its ANDA it did not seek approval to commercially manufacture, use or sell a pharmaceutical composition of nifedipine until after the expiration of the '627 patent."

Pfizer is seeking a court order prohibiting FDA from approving the capsulated nifedipine products until the 1991 expiration of the '627 patent, an injunction that would block Barr from the commercial manufacture, use or sale of nifedipine as well as treble damages arising from patent infringement. Barr maintains that its nifedipine product is produced by a different manufacturing process and therefore does not infringe Pfizer's patent.