Bristol-Myers Squibb Co. v. Teva Pharmaceuticals USA, Inc.

A drug's unexpected properties alone are insufficient to establish non-obviousness.

Opinion (Chen): Bristol–Myers Squibb Co. (BMS) appealed a United States District Court for the District of Delaware judgment that claim 8 of U.S. Patent No. 5,206,244 was invalid as obvious. BMS markets entecavir as a treatment for hepatitis B under the trade name Baraclude. Teva Pharmaceuticals USA, Inc. (Teva), filed an abbreviated new drug application (ANDA) for a generic version of entecavir, alleging that BMS’s patent was invalid or unenforceable for obviousness. To establish obviousness in cases involving new chemical compounds, the accused infringer (Teva) "must identify some reason that would have led a chemist to modify a known compound." BMS argued that regardless of any reasons for modifying a new chemical entity, the invention cannot be obvious when it possesses unexpected properties. The Court held that unexpected results do not per se defeat the finding that a modification to a lead compound will yield expected, beneficial properties. After considering all of the findings for and against obviousness, the district court's judgment that claim 8 of the ′244 patent was invalid as obvious was AFFIRMED.