Section 3(d) is a great piece of legal provision, carefully drafted to negate patent protection for trivial and obvious improvements, in general, made to already known pharmaceutical/chemical substances. Notably, wording of section 3(d) is not open-ended but clearly conditional which leaves room for patent protection for incremental innovations. In fact, any patent application that is rejected u/s section 3(d) must strictly fall within the condition laid down by the section 3(d). However, the application of the section 3(d) by the Indian Patent Office, and more particularly by the Indian Judiciary raised serious questions about the understanding and spirit of section 3(d). In this post, I will try to raise certain points that often puzzled me about the way section 3(d) is interpreted and applied by the Indian Patent Office and Indian Judiciary. I will sincerely welcome and appreciate comments by the readers which help to clarify and add value to the points made in the post.
In Novartis infamous Glivec case, the Madras High Court opined that the efficacy under section 3(d) need to be construed as “therapeutic” efficacy only. Strictly adhering to the Madras High Court opinion, improved efficacy does not include any enhancement in pharmacological parameters (such as bioavailability, toxicity, increased self-life, stability and so on). This mean any physical or chemical improvement made to a known drug substance cannot qualify for patent protection unless and until they do not result into enhanced therapeutic efficacy. Let us consider the Imatinib case. Novartis applied patent application for beta-crystalline form of Imatinib Mesylate which was denied by the IPO and later by the Madras High Court suggesting that improved bioavailability do not account to enhanced therapeutic efficacy.
Suppose if Novartis wanted to have a patent protection for beta-crystalline form of Imatinib Mesylate then what data they need to provide to the IPO in light of the Madras High Court decision? Simple! Novartis need to provide clinical data to prove that beta-crystalline form of Imatinib Mesylate is therapeutically enhanced in treating chronic myelogenous leukemia (CML) when compared to known Imatinib Mesylate substance. In other words, Novartis need to prove that beta-crystalline form is better than known substance not in terms of bioavailability or any other pharmacological parameters but in terms of therapeutic treatment activity (may be something like improving inhibition activity towards tyrosine kinase enzymes). Now the first point that come to my mind is that whether a polymorph or a salt of a known drug substance can improve therapeutic treatment activity, that is, mechanism of drug action of the known drug substance or they are used for improving pharmacological parameters of the know drug substances? I may be wrong in my understanding on this issue but surely would love to hear comments from readers and the industry experts. Whether the Madras High Court opinion of restricting efficacy only to therapeutic efficacy jeopardizes innovation?