BARR LABS TO SELL GENERIC TAMOXIFEN (NOLVADEX) BEGINNING NOV. 1

BARR LABS TO SELL GENERIC TAMOXIFEN (NOLVADEX) BEGINNING NOV. 1 under a patent litigation settlement with ICI announced March 8. Under the agreement, Barr will receive $21 mil. in cash from ICI and will enter into a non-exclusive distribution arrangement for the breast cancer drug with Zeneca, Inc., ICI's recently formed U.S. bioscience affiliate. Barr's ANDA for a generic version of tamoxifen citrate was approved on April 1, 1987. ICI then filed an infringement suit against the generic manufacturer. Manhattan federal court Judge Vincent Broderick ruled in April 1992 that ICI's patent was unenforceable ("The Pink Sheet" May 4, 1992, p. 8). ICI appealed that ruling. The settlement is contingent upon Broderick's ruling being vacated and dismissal of the case. A press release issued jointly by the two companies states that Barr has recognized that "there were genuine issues presented on appeal and risks of litigation," adding that the two firms also agreed "there was a substantial possibility that ICI's United States patent on tamoxifen would have been held valid and enforceable." The patent for the anti-estrogen expires in 2002. The agreement has advantages for both sides: ICI will not have to risk its patent protection in court, and Barr can look forward to revenue from an externally supplied product in the face of recent manufacturing compliance problems. Distribution of 24 of Barr's 58 products, representing 40% of the firm's annual sales, was ordered suspended due to GMP violations by Newark federal court Judge Alfred Wolin on Feb. 4 ("The Pink Sheet" Feb. 8, T&G-1). Barr's tamoxifen will be manufactured at Zeneca's Newark, Del. production facility and distributed from Barr's plant in Northvale, N.J. under the Barr label. ICI's patent for tamoxifen has been rescinded before. After initially granting the patent in 1967, the U.S. Patent and Trademark Office subsequently repealed it. In 1985, ICI regained the patent through a federal appeals court, eight years after Nolvadex' December 1977 approval. ICI has worked in the past to position itself in the generic market before a patent on a leading product has expired: its generic subsidiary, IPR Pharmaceuticals, was created to manufacture and sell an "authorized" generic version of Tenormin (atenolol) prior to patent expiry. IPR launched a generic version of ICI's Tenoretic (atenolol/chlorthalidone) last summer when Danbury successfully challenged its hypertension use patent on atenolol ("The Pink Sheet" June 29, 1992, T&G-1). Nolvadex generated sales of $265 mil. in 1992. The drug is currently indicated for adjuvant therapy in breast cancer and for advanced breast cancer. Tamoxifen eventually could have a much wider market if it is shown to be effective in the prevention of breast cancer. The drug is currently the subject of a National Cancer Institute 16,000-patient breast cancer prevention trial.