ERBAMONT's DOXORUBICIN PATENT INFRINGEMENT FILINGS

ERBAMONT's DOXORUBICIN PATENT INFRINGEMENT FILINGS against Cetus and Bristol-Myers allege that the manufacturing processes for the two companies' doxorubicin products infringe Erbamont's process patent. On April 12, Erbamont filed a complaint for patent infringement against Cetus Corporation, and a counterclaim against Bristol-Myers. The filings were made in the Federal District Court for Delaware. In its complaint against Cetus, Erbamont asserts the firm is selling or plans to sell "doxorubicin products that are made by a process which comes within the scope of and is encompassed by the invention described and claimed in the '124 patent." The Erbamont patent expires in April 1991. Erbamont's filings follow an April 11 filing by Cetus for a declaratory judgment of patent invalidity, unenforceability and non-infringement. In March, Bristol-Myers submitted a request for the same declaratory judgment. Cetus-Ben Venue, a 50/50 joint venture between the biotech firm Cetus and the generic drug manufacturer Ben Venue Labs, received approval for the first generic doxorubicin product on March 17 ("The Pink Sheet" March 27, T&G-14). Bristol-Myers has an ANDA pending for doxorubicin for which approval "is expected shortly," the company noted in its court submission. Erbamont's branded doxorubicin product Adriamycin is marketed in the U.S. by its subsidiary, Adria Labs. Cetus has estimated sales of Adriamycin in 1988 at over $ 140 mil. in the U.S. and Canada. The product patent for Adriamycin, the world's biggest selling anticancer drug, expired in June 1988. Cetus and Bristol-Myers are maintaining that Erbamont's process patent is not infringed because the processes used to manufacture their bulk doxorubicin fall outside the scope of the patent. The two companies also claim that the process patent is invalid and unenforceable due to "inequitable conduct and fraud" in attaining the process patent. The firms allege that Erbamont failed to disclose information and prior art on the invention to the U.S. Patent and Trademark Office. Cetus receives its supply of bulk doxorubicin from U.K.-based ALCO Chemicals, which is a distributor for the firm Societa Italiana Corticosteroidi (SICOR). SICOR gained approval for the first generic bulk doxorubicin in December. Bristol-Myers manufactures its doxorubicin by using bulk daunorubicin supplied by the Japanese firm Meiji Seika Kaisha. Meiji received approval for doxorubicin's precursor compound in March.