Pioglitazone Survived Post-KSR Obviousness Standard

Takeda Chem. et al. v. Alphapharm et al. (Fed. Cir. 2007) Ever since the US Supreme Court laid down its KSR ‘common sense’ syndrome, the US pharma industry is being constantly surrounded by the speculations quantifying the impact of the KSR obviousness standards over the ongoing and future patent litigations. However, in one of the major development, the US Court of Appeals for the Federal Circuit (CAFC) has put an end to some of the speculations after it knocks down Alphapharm et al. assertion over the Supreme Court’s decision in KSR v. Teleflex and Federal Circuit’s decision in Pfizer v. Apotex (Norvasc) in challenging obviousness of the US Patent No. 4,687,777 (the ‘777 patent) which covers chemical compound pioglitazone hydrochloride. This case is of great importance to pharma industry as the CAFC meritoriously negate the application of KSR and Norvasc obviousness test to evaluate the obviousness of chemical (species) compound. Last year on February 21, Judge Denis Cote ruled in the favor of Takeda after generic drug manufacturers Alphapharm and Mylan failed to establish obviousness and inequitable conduct against the ‘777 patent. During the district court trial, Alphapharm identified two key prior art literatures – US Patent No. 4,287,200 (the ‘200 patent) and a publication by Dr. Sohda to challenge the obviousness of the ‘777 patent. However, the district court later found that Alphapharm’s arguments failed to show any persuasive evidence, much less by clear and convincing evidence, that one with ordinary skill in the art have had any reasonable expectation or motivation based on the prior art for synthesizing pioglitazone. Moreover, Alphapharm appealed the district court judgment. In its appeal, Alphapharm argued that the ‘777 patent would have been obvious under 35 USC § 103 at the time invention was made. Alphapharm made three distinctive arguments to support its contention for obviousness – First, that the district court misapplied the law, particularly the law governing obviousness in the context of structurally similar chemical compounds. Second, that the district court erred in determining the scope and content of the prior art. Lastly, that the district court erred in numerous legal and factual determinations and certain evidentiary rulings made during course of the trial. The CAFC addressed above arguments by applying time-tested Graham Factors along with the obviousness standards laid down by KSR and Norvasc decisions. To be continued…