The Bench of the Supreme Court of India, in its landmark judgment of 112 pages rejected the plea for patent protection to anti-cancer drug Glivec/Gleevec filed by Novartis in 1998.
The active pharmaceutical ingredient of Glivec/Gleevec is a specific chemical form of imatinib, namely, the beta polymorph of imatinib mesylate, which exhibits greater stability and bioavailability than the alpha polymorph. A patent for the free base of imatinib was first granted in 1996 to Novartis. Novartis thereafter filed and obtained separate patents for the specific formulation used as the active ingredient of Glivec/Gleevec in several countries.
In 1998, Novartis filed a patent application in India for the Beta crystalline variant of the molecule, which was derived from the amorphous substance that they had earlier patented. During 1995 to 2005, as permitted by TRIPS, patent applications for pharmaceutical substances were received by the Indian Patent Office but were not examined and kept on hold. Such applications are popularly termed as 'mailbox applications.' After 2005 amendment of the Indian Patents Act, the examination of such patent applications started. In January 2006 the patent application of Novartis was rejected by the patent office on the ground that it did not satisfy the efficacy criterion of section 3(d). Novartis persisted in its efforts to get a patent and appealed to the Intellctual Property Appellate Board (IPAB) wherein the application was again rejected. When the IPAB rejected Novartis' application, the company challenged the decision in the Chennai High Court and also challenged section 3(d) of the Indian Patents Act. The Chennai High Court rejected both the appeals, which led to Novartis bringing its appeal to the Supreme Court of India.
In the Supreme Court, Novartis challenged the interpretation of Section 3(d) of the Indian Patents Act. Novartis, in its appeal to the Supreme Court, argued that section 3(d) is not being properly interpreted. The section says that minor variations in an existing molecule cannot be patented unless there is a 'significant' enhancement in efficacy of the medicine. Novartis claimed that since the Beta variant is better absorbed – i.e, it has better 'bioavailability' (by about 30 per cent) it constitutes a significant therapeutic enhancement.
The Supreme Court in its judgment opined: "The subject product, that is, beta crystalline form of Imatinib Mesylate, is thus clearly a new form of a known substance, i.e., Imatinib Mesylate, of which the efficacy was well known. It, therefore, fully attracts section 3(d) and must be shown to satisfy the substantive provision and the explanation appended to it". Further Supreme Court also opined: "In whatever way therapeutic efficacy may be interpreted, this much is absolutely clear: that the physico-chemical properties of beta crystalline form of Imatinib Mesylate … may be otherwise beneficial but these properties cannot even be taken into account for the purpose of the test of section 3(d) of the Act, since these properties have nothing to do with therapeutic efficacy". In regard to the increased bio-availability, Supreme Court observed that: "No material has been offered to indicate that the beta crystalline form of Imatinib Mesylate will produce an enhanced or superior efficacy (therapeutic) on molecular basis than what could be achieved with Imatinib free base…."
Supreme Court interpreted the word 'efficacy' to mean therapeutic efficacy of the drug and hence rejected the appeal made by Novartis and denied the patent because Novartis could not demonstrate that the new form of the said drug enhanced the therapeutic efficacy. Further, the court also rejected Novartis claims of better bioavailability and better physical characteristics such as stability of the compound saying that these do not necessarily improve the therapeutic effect.
Disclaimer: The sole purpose of this article is for information only; and not to be construed for any legal advice. The article was drafted, based on the information considered upto 29th July, 2013.