The Indian Supreme Court has ruled that Novartis is not entitled to receive patent protection for its anti-cancer drug GlivecTM. The patent application relates to a new version of the active ingredient, the beta-crystalline form of Imatinib Mesylate, which was found to violate the provisions of Section 3(d) of the Indian Patents Act. This section requires a new form of a known pharmaceutical substance to be more effective than previous forms. While the decision is undoubtedly a blow to the pharmaceutical industry, the Court made it clear that Section 3(d) can be overcome, provided that evidence showing improved efficacy is provided.
In 1994 Novartis sought patent protection for Imatinib as a pharmaceutical substance per se and was granted a patent in many territories. However, India’s Patent Law blocked the grant of a patent to Imatinib at that time. Revisions to India’s Patent Law to meet obligations under the TRIPs Agreement allowed Novartis to file an application in 1998 for a new form of the active ingredient– the beta crystalline form of Imatinib Mesylate. The application was put on hold until India formally allowed patents to directly cover pharmaceutical substances.
In 2005 the Indian Patents Act was further amended to introduce Section 3(d), following concerns from various sources, both within and outside of India. Section 3(d) limited the ability of pharmaceutical companies to obtain patents on the basis of incremental improvements and states that an invention cannot be,
“…the mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance or the mere discovery of any new property or new use for a known substance or of the mere use of a known process, machine or apparatus unless such known process results in a new product or employs at least one new reactant.”
The revised Act explains that a salt or a polymorph of a known substance is considered to be the same substance unless it has improved efficacy. Therefore, in addition to the normal requirements of patentability, a new form of a known chemical must also pass a further “improved efficacy” hurdle in India.
Novartis argued that Imatinib Mesylate was not disclosed in the 1994 patent. However, the Court held that Imatinib Mesylate was anticipated, even though the Mesylate salt was not disclosed, on the grounds that the 1994 patent covered all salts of Imatinib. However, despite this reasoning, the Court found the beta crystalline form of Imatinib Mesylate to be novel (even though it can be described as Imatinib Mesylate too). This allowed the Court to consider whether the beta form of Imatinib Mesylate met the requirements of Section 3(d).
Novartis had submitted data comparing the solubility and bioavailability of the beta form of Imatinib Mesylate to that of Imatinib itself. In addition, further data highlighted the physical differences between the beta and alhpa forms of Imatinib Mesylate too. The Court dismissed the solubility data and physical differences because these did not impact on the efficacy of the compound in question. This left only the bioavailability difference, which was dismissed in this case because no data was provided by Novartis that showed any improvement in efficacy over Imatinib in vivo. Therefore, the additional hurdle posed by Section 3(d) was not cleared and Novartis was denied protection for GlivecTM in India.
While this decision case is certainly important, it is unlikely to result in patent protection being denied for all incremental pharmaceutical inventions in India. The Supreme Court was at pains to make this clear in their closing comments, where they stated that it would be a grave mistake to think that Section 3(d) prevents chemical substances (particularly incremental improvements of such substances) from obtaining patent protection directly. Therefore, it appears that a new form of a chemical substance can overcome the hurdle set by Section 3(d) in the Indian Patent Act, if clear and convincing evidence of this efficacy can be provided.