In 1997, Novartis AG filed a patent application in the Chennai ( Madras) Patent Controller’s office for the beta-crystalline of Imatinib Mesylate, brand name Glivec (Gleevec) on the ground that they invented the beta crystalline salt form (imatinib mesylate) of the free base, imatinib. In 2003, it was granted Exclusive Marketing Rights (EMR) for marketing Gleevec in the Indian market. On the basis of the EMR, Novartis AG obtained orders preventing some of the generic manufacturers from generic equivalents of Gleevec.

Novartis was selling Gleevec at USD 2666 per patient per year. Generic companies were selling their generic versions at USD 177 to 266 per patient per month.In 2005, the CPAA and the other generic companies filed a pre-grant opposition against Novartis’ patent application for imatinib mesylate, claiming, among other things, that Novartis’ alleged “invention” lacked novelty, was obvious to a person skilled in the art, and that it was merely a “new form” of a “known substance” that did not enhance the substance’s efficacy, and was thus not patentable under section 3(d) of the Patents Act. These arguments were based on the fact that Novartis had already been granted a patent in 1993 for the active molecule, imatinib, and that the present application only concerned a specific crystalline form of the salt form of that compound.The CPAA and the generic companies contended that the 1993 patent effectively disclosed both the free base, imatinib, and the acid-addition salt, imatinib mesylate. Further, the CPAA and generic companies argued that different crystalline forms of imatinib mesylate did not differ in properties with respect to efficacy, and thus the various forms of imatinib mesylate must be considered the “same substance” under section 3(d) of the Patents Act.

In January 2006, the Patent Controller in Chennai, in a landmark decision, refused to grant Novartis a patent, agreeing with the contentions of the CPAA and generic companies that the subject application lacked novelty, was obvious, and was unpatentable under section 3(d) of the Act.The patent rejection meant that generic companies could manufacture and market their drug, both in India and abroad, who make available the generic imatinib mesylate priced at less than one-tenth the price that Novartis was charging (USD 166 to 266 instead of 2666 per person per month).