The U.S. Court of Appeals for the Federal Circuit (CAFC) in Eli Lilly & Co. v. Teva Pharmaceuticals USA, Inc.(Fed. Cir. 2010) affirmed a permanent injunction against Teva barring manufacture of a generic version of the osteoporosis drug raloxifene until the expiration of certain patents of Lilly.
Throughout the development of the drug, various studies indicated that raloxifene had poor bioavailability. Despite such concerns, Lilly developed the drug for both the indications of breast cancer and postmenopausal osteoporosis. Teva alleged obviousness and lack of enablement among the various points of attacks.
Regarding obviousness, Teva relied on statements by Lilly’s Bone Biology Group chairman and on actions of Lilly’s scientists in pursuing the development of the drug as evidence that they had to have a reasonable basis for believing that the drug would work in humans, otherwise they would not have proceeded. The CAFC held that the chairman had more knowledge than one of ordinary skill in the art, and that Lilly’s scientists had both knowledge and credentials superior to the ordinary artisan, thereby rendering these statements and actions not available as evidence of obviousness. Rather, a person of ordinary skill in the art would have been discouraged from using raloxifene in view of its known low bioavailability, and thereby the patents were not invalid for obviousness.
Regarding enablement, Teva argued that if the concerns about bioavailability did not render the claims obvious, then the disclosures of the patents at issue could not have been enabling because of the prevailing view that raloxifene would not work in humans. The CAFC held, however, that because the patent disclosures provided more information than the prior art, i.e., the results of a further study and the details–albeit no results–of an ongoing human clinical study, the disclosures are enabling. Regarding the description of the details of a human clinical study, reliance was based on the Manual of Patent Examining Procedure (MPEP), which supports that the initiation of a clinical trial has a significant impact on the utility inquiry. The MPEP states that:
Before a drug can enter human clinical trials, the sponsor, often the applicant, must provide a convincing rationale to those especially skilled in the art (e.g., the Food and Drug Administration) that the investigation may be successful. Such a rationale would provide a basis for the sponsor’s expectation that the investigation may be successful … Thus, as a general rule, if an applicant has initiated human clinical trials for a therapeutic product or process, Office personnel should presume that the applicant has established that the subject matter of that trial is reasonably predictive of having the asserted therapeutic utility.