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

Bristol-Myers created a new chemical compound: entecavir. Its structure is a modification of a prior-art compound, apparently a common phenomenon in pharmaceutical chemistry, where small changes can make large differences. The prior-art compound (2'-CDG) was described in published papers. It had shown excellent activity against certain viruses, including the hepatitis B virus, in tests on cell lines in in vitro experiments; but it had never been tested even in animals, let alone humans, whether for efficacy or toxicity. Bristol-Myers’s novel compound proved to be effective and nontoxic (safe)…