Novartis’ Indian patent application No 1602/MAS/1998 at the Chennai Patent Office on 17 July 1998 relating to a beta crystalline form of imatinib mesylate had initially been rejected by the Controller of Patents under section 3(d) of the Indian Patents Act, 1970 (Act). According to section 3(d), a new form of a known substance is not patentable in India unless the new form showed “enhancement of the known efficacy” of that substance.
Novartis filed writ petitions before the Madras High Court in May 2006, claiming that the Controller erred in rejecting its patent application, and further claiming that section 3(d) was, inter alia, vague, ambiguous, and contrary to the requirements of the Trade Related Aspects of Intellectual Property Rights (TRIPS) of the WTO Agreements. In the challenge to section 3(d), Novartis had argued that this provision is not in compliance with TRIPS and was in violation of the Indian government’s constitutional duty to harmonise its domestic laws with its international obligations under TRIPS. The Madras High Court held that it was not the proper forum to decide whether the Indian patent law was TRIPS compliant or not. Dismissing the petition, the Madras High Court held that section 3(d) was not vague or arbitrary and therefore did not violate the Indian Constitution. Novartis’ challenge to the Controller’s decision rejecting the patent, which was filed before the Madras High Court, was subsequently transferred to the Intellectual Property Appellate Board (IPAB).
Before the IPAB, Novartis had argued that the beta crystalline form of imatinib mesylate had, inter alia, improved bioavailability, lower hygroscopicity, improved thermodynamic stability and improved flow properties. The IPAB, in 2009, upholding the Controller’s decision, interpreted the term “enhancement of the known efficacy” to mean improved therapeutic efficacy of the new form and not merely improved bioavailability or improved physical properties. Novartis then appealed against the IPAB’s order before the Supreme Court.
The apex court of India upheld the IPAB’s order refusing grant of a patent to Novartis’ product. According to the judgement, in case of chemicals and especially pharmaceuticals if the product for which patent protection is claimed is a new form of a known substance with known efficacy, then the subject product must pass, in addition to section 2(1)(j) and 2(1)(ja), the test of enhanced efficacy as provided in section 3(d) read with its explanation. With regard to the interpretation of the term “enhancement of the known efficacy”, the Supreme Court reasoned that “not all advantageous or beneficial properties are relevant, but only such properties that directly relate to efficacy, which in case of medicine, as seen above, is its therapeutic efficacy.” The Supreme Court decided that Novartis’ product fails to qualify as an invention under section 2(1)(j) and 2(1)(ja) and also fails the test of patentability under section 3(d).
The Supreme Court decision this morning makes it very clear that in order to obtain a patent for a new form of a known substance in India, the applicants must show in their patent specification, sufficient proof that the new form of a base compound of known substance is therapeutically more efficacious than the base compound or known substance. Experimental data to establish that the new form has a therapeutic advantage will be essential in determining whether the new form will qualify for a patent in India vis-à-vis section 3(d) of the Act.