Sitagliptin (Januvia) patent litigation: Another link in the judicial train of ‘Proactive Infringement’ of patented rights in developing countries

Abstract

Driven by increasing instances of successful ‘at-risk’ launch of patented drugs in America and Europe, the strategy of using ‘proactive infringement’ as a legal tool is now getting-in, in developing countries. The rationale behind launch-at-risk is to counterbalance the innovator companies’ strategies of getting the patented product life extended through protecting improvement innovations and maintain market exclusivity even after the expiration of the compound patent. The battle for market and drive for higher profits between generics and innovator drug companies has extended the application of at-risk launch of the generic drugs even when compound patent is still running. Sitagliptin (Januvia) may be ranked at top of the drugs that have been fiercely litigated in the developing countries during their patent term. This article reviews the outcome of sitagliptin patent litigation and impact on the market exclusivity in some developing countries. This takes the position that the existing conflict between the innovators and generics can be resolved by diluting the misconception that patents on improvement innovations are misuse of patent system or inappropriate extension of patented product life on the part of innovator companies. Whether trivial, simplified or complex, if novel and non-obvious, further improvements in the precursor drugs are patentable within the legal framework of the patent system. The real issue is the scope of monopoly granted to the secondary or follow-on patents. Once the compound patent has expired, follow-on patents on improvements relating to the same compound should not be allowed to use as legal-barrier for the generic medicines entry to the market.

Biocatalysis for the asymmetric synthesis of Active Pharmaceutical Ingredients (APIs): this time is for real

“…As Januvia ® was already on the market (since 2006, protected by different patents [89][90][91]) when the biocatalytic synthesis was ready for implementation [92], a refile with regulatory agencies was required [93]. In any case, sitagliptin patents protection is about to end (July 2022 for sitagliptin, November 2026 for the phosphate salt [94]) and the enzymatic procedure, easily scalable [95,96], was demonstrated on a 45 kg scale [92]. Some further studies from the same group showed how the immobilization of the engineered enzyme on a polymeric resin (SEPABEADS EXE120) displayed excellent performance (activity and stability) under the optimized process conditions, allowing multiple rounds of enzyme reuse without any detectable loss of activity [97].…”