Imatinib Mesylate tablets (Gleevac): IP Appellate Board refused patent to innovator Novartis in India

In a significant and pro-patient judgment, the Intellectual Property Appellate Board (IPAB), has ruled that innovator Novartis's controversial anti-cancer drug, Imatinib Mesylate tablets (Gleevac), lacks patentability and refused patent to innovator.

The said patent was challenged by Indian generic players like Natco, Ranbaxy, Cipla and some NGO’s like Cancer Patient Aid Association.The IPAB panel of Z.S Negi (chairman) and PC Chakraborty (Technical Member) opined that the beta crystalline version of Imatinib Mesylate was not patentable under Section 3(d) of the Indian Patent Act and the molecule do not have enhanced efficacy in comparison to earlier known pharmaceutical derivatives.

Imatinib was first discovered as free base and innovator filed patent application in regulated market (US & Europe) around 1993. Later on, innovator improved various physical and chemical fetures of Imatinib by preparing as mesylate salt. Further during pre-formulation studies, innovator obtained thermodynamically stable and lesser hygroscopic crystalline form Beta of Imatinib Mesylate. The patent application on crystalline form Beta of Imatinib Mesylate was opposed in India. The marketed Imatinib Mesylate tablets (Gleevac) contains crystalline form Beta.

Earlier, innovator Novartis filed patent application in 1999 on crystalline form Beta of Imatinib Mesylate, subsequently; Chennai patent office rejected the patent application under section 3(d) of Indian patent act. Novartis appealed against this decision to IPAB. Also, Novartis unsuccessfully challenged Indian patent section 3(d).

As per section 3(d) of Indian patent act, incremental inventions of known substances like the pharmaceutical acceptable salts, esters, polymorphs, metabolites, particle size, complexes, co-crystals, combinations are unpatentable unless they differ significantly in terms of therapeutic efficacy.


The IPAB also acknowledged the fact that innovator has successfully patented similar invention in about 35-40 other countries, however, for country like India the treatment would cost around 1.2 lac per month, which is quite high for poor patients.

Also, board opined that claims in the patent are novel and non-obvious to person having ordinary skilled in the art, however, the invention has not significantly enhanced therapeutic activity to overcome patent application rejection under Indian patent act’s section 3(d).