On December 29, 2021, the Beijing Intellectual Property Court (the Court) maintained the validity of CN Invention Patent No. ZL200680025545.1 (the ’545 patent), which reversed an invalidation decision made by the Patent Reexamination and Invalidation Department of the China National Intellectual Property Administration (CNIPA). The Court held that the claimed invention is inventive because one person of ordinary skill in the art would not have been motivated to modify three specific positions of the asserted prior art compound (right) with specific substituents, respectively, to obtain the claimed compound (left) in view that one prior art reference discloses the possibility of making at least 200 million compounds:
(1) Substituting C=O at the 2-position of the imidazole ring with C=S.
(2) Substituting a chlorine-substituted benzene ring with a fluorine-substituted benzene ring.
(3) Substituting -NHCO- with -CONH-.
The Court acknowledged the low predictability in the pharmaceutical inventions, and therefore appreciated the non-obviousness of the claimed compound in view of the prior art.