Bristol-Myers Squibb Co. v. Teva Pharms USA, Inc.
Addressing the obviousness of a claimed compound where a person of skill would need to make only minor changes to a lead compound to arrive at the claimed invention, the U.S. Court of Appeals for the Federal Circuit affirmed a district court’s ruling, finding that the pharmaceutical was obvious where a skilled artisan would have altered the lead compound of the prior art in the exact same manner suggested by defendant. Bristol-Myers Squibb Co. v. Teva Pharms USA, Inc., Case No. 13-1306 (Fed. Cir., June 12, 2014) (Chen, J.).
Bristol-Myers (BMS) sued Teva for infringing a patent directed to entecavir, a nucleoside analogue with antiviral properties. BMS marketsentecavir for treating hepatitis B under the brand name Baraclude. Teva filed an Abbreviated New Drug Application (ANDA) seeking to market a generic version of entecavir accompanied by a Paragraph IV certification. In response, BMS sued for infringement. Teva counterclaimed that entecavir was obvious in view of 2’-CDG, a “lead compound” disclosed in the prior art that differed from entecavir by a single alteration to entecavir’s molecular structure.
The district court found that 2’-CDG was a lead compound based on its potent anti-hepatitis B activity and that many groups and companies have investigated its antiviral properties. The court also found that the structural similarity between 2’-CDG and entecavir, combined with prior art teachings that disclosed other, similar compounds, would have motivated a skilled artisan to modify 2’-CDG to make entecavir. The court concluded that a person of skill would have had a reasonable expectation of success and found the claims to be obvious. BMS appealed.
The Federal Circuit, drawing from detailed evidence and testimony, affirmed the district court and concluded that a skilled artisan would have altered 2’-CDG in exactly the manner that led to entecavir. The Court agreed that the evidence showed that only a minor change to 2’-CDG would have been required to convert it to entecavir and that other prior art provided motivation to do so. According to the Court, the district court properly found strong evidence of obviousness, because the record shows that a skilled artisan would have selected 2’-CDG as a lead compound and made the minor modification to arrive at entecavir.
The Federal Circuit rejected BMS’s argument that 2’-CDG could not have been a lead compound because of its toxicity, a characteristic discovered after the priority date. According to the Court, any such later discovery would not have affected a skilled artisan’s evaluation of the compound at the time of invention, and was thus immaterial. Citing In re Dillon (Federal Circuit, 1990) (en banc), the Court further held that unexpected results do not foreclose an obviousness finding, and it agreed with the district court that the evidence of unexpected results and any other secondary considerations produced in the litigation, did not overcome the strong evidence of obviousness.