Rivastigmine patent, SPC held invalid

Via a LexisNexis update (since it's not yet available on BAILII) comes news of Generics (UK) Ltd (t/a Mylan) v Novartis AG [2011 EWHC 2403 (Pat), a 30 September 2011 decision of the Patents Court, England and Wales, by Mr Justice Floyd.

In brief it appears that Generics applied for declarations of invalidity in respect of Novartis's SPC GB9B/038 as well as its underlying patent, UK patent 2 203 040, which covered rivastigmine (sold as Exelon), a drug for the symptomatic treatment of Alzheimer's disease of which Generics sought to market a generic version.

Back in 1985 a team of scientists led by Marta Weinstock had made and tested a compound, RA7, which was the unresolved racemic compound of which rivastigmine was the (-) enantiomer. RA7 was one of a number of compounds she proposed for treating Alzheimer's, but her publications made no mention of resolving it into its individual enantiomers. Generics contended that the patent lacked inventive step. Novartis counterclaimed that Generics' threatened marketing of a generic version of rivastigmine would infringe the SPC and sought appropriate relief.

In these proceedings the sole issue was whether a relevantly skilled pharmaceutical development team, without knowledge of Novartis's patent, would have found it obvious in the light of the Weinstock publications to resolve the racemic mixture of RA7 into its individual enantiomers.

Floyd J allowed the claim and dismissed the counterclaim, holding both the SPC and the patent invalid.

In his view the correct analysis was that a pharmaceutical composition for treatment of Alzheimer's comprising rivastigmine was conceptually obvious in the light of Weinstock and would immediately occur to the skilled team: the team would consider that resolving R A7 would be a worthwhile step to take for good technical reasons, finding the chemistry involved to be trivial. Accordingly there was no doubt that the inventive concept was obvious in the light of Weinstock.

At first blush this looks like a pure and simple invalidity case. Once the judgment is available we will be able to see if anything of note was said about the SPC.