Thursday, April 4, 2013

Improvements which enhance therapeutic efficacy of a medicine are patentable

No patents for improvements to existing medicines other than improvements in therapeutic efficacy in view of higher “patentability” threshold in section 3(d) of the Patents Act.

Novartis’ Patent application for cancer medicine rejected by SC as it was “copy and paste” of Zimmermann patent and mere change in form with no improvement in therapeutic efficacy, hence, hit by section 3(d) of the Patents Act.

In the instant case, the appellant (Novartis) filed the application for grant of patent for Imatinib Mesylate in beta crystalline form at the Chennai Patents Office. The Assistant Controller of Patents and Designs held that the patentability of the alleged invention was disallowed by section 3(d) of the Act. Appellant’s appeal was dismissed by the IPAB. Hence, the appellant filed present SLP to SC against IPAB‘s orders under article 136 of the Constitution.

Supreme Court held against appellant as under:

1) For grant of patent the subject must satisfy the twin tests of “invention” and “patentability”. Something may be an “invention” as the term is generally understood, yet it may not qualify as an “invention” for the purposes of the Act. Further, something may even qualify as an “invention” as defined under the Act, yet may be denied patent for larger considerations as may be stipulated in the Act;

2) After the amendment with effect from Jan 1, 2005, section 3(d) reads as under:

“Section 3. What are not inventions? The following are not inventions within the meaning of this Act,—(d) 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 aforementioned amendment to section 3(d) is one of the most crucial amendments that saw the Bill through the Parliament and, as noted, the amendment is primarily in respect of medicines and drugs and, to some extent, in respect of chemical substances used in agriculture.

3) There is no force in this submission that section 3(d) is a provision ex majore cautela. In course of the Parliamentary debates, the amendment to section 3(d) was the only provision cited by the Government to allay the fears of the opposition members concerning the abuses to which a product patent in medicines may be vulnerable to. We have, therefore, no doubt in that the amendment/addition made to section 3(d) is meant especially to deal with chemical substances, and more particularly with  pharmaceutical products.

4) The amended portion of section 3(d) clearly sets-up a second tier of qualifying standards for chemical substances/pharmaceutical products in order to leave the door open for true and genuine inventions but, at the same time, to check any attempt at repetitive patenting or extension of the patent term to spurious products. Section 3(d) represents “patentability”, a concept distinct and separate from “invention”.

If clause (d) is isolated from the rest of section 3, and the legislative history behind the incorporation of Chapter II in the Patents Act, 1970, is disregarded, then it is possible to see section 3(d) as an extension of the definition of “invention” and to link section 3(d) with clauses (j) and (ja) of section 2(1);

5) On reading clauses (j) and (ja) of section 2(1) with section 3(d) it would be clear that the Act sets different standards for qualifying as “inventions” in case of things belonging to different classes.  For medicines and drugs and other chemical substances, the Act sets the invention threshold even higher, by virtue of the amendments made to section 3(d) in the year 2005;

6) Imatinib Mesylate is a known substance from the Zimmermann patent itself. Not only is Imatinib Mesylate known as a substance of the Zimmermann patent, but its pharmacological properties are also known in the Zimmermann patent.  In the article published in the Cancer Research journal, the consequential finding is that Imatinib Mesylate does not qualify the test of “invention” as laid down in section 2(1)(j) and section 2(1)(ja) of the Patents Act, 1970;

7) The efficacy of Imatinib was equally known, as is evident from the Zimmermann patent itself. 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.

8) Now, when all the pharmacological properties of beta crystalline form of Imatinib Mesylate are equally possessed by Imatinib in free base form or its salt, where is the question of the subject product having any enhanced efficacy over the known substance of which it is a new form?.

9) On the issue of section 3(d), there appears to be a major weakness in the case of the appellant. There is no clarity at all as to what is the substance immediately preceding the subject product - the beta crystalline form of Imatinib Mesylate? In course of the hearing, the counsel appearing for the appellant greatly stressed fact that in terms of invention, the beta crystalline form of Imatinib Mesylate is two stages removed from Imatinib in free base form. The same is said in the written notes of submissions filed on behalf of the appellant. But this position is not reflected in the subject application, in which all the references are only to Imatinib in free base form (or to the alpha crystalline form of Imatinib Mesylate in respect of flow properties, thermo-dynamic stability and lower hygroscopicity);.

10) What is “efficacy”? Efficacy means1 “the ability to produce a desired or intended result”. Hence, the test of efficacy in the context of section 3(d) would be different, depending upon the result the product under consideration is desired or intended to produce. In other words, the test of efficacy would depend upon the function, utility or the purpose of the product under consideration. Therefore, in the case of a medicine that claims to cure a disease, the test of efficacy can only be “therapeutic efficacy”. The question then arises, what would be the parameter of therapeutic efficacy and what are the advantages and benefits that may be taken into account for determining the enhancement of therapeutic efficacy?

11) With regard to the genesis of section 3(d), more particularly, the circumstances in which section 3(d) was amended to make it even more constrictive than before, we have no doubt in that the “therapeutic efficacy” of a medicine must be judged strictly and narrowly. Our inference that the test of enhanced efficacy in case of chemical substances, especially medicine, should receive a narrow and strict interpretation is based not only on external factors but also on sufficient internal evidences that lead to the same view. It may be noted that the text added to section 3(d) by the 2005 amendment lays down the condition of “enhancement of the known efficacy”;

12) Further, the Explanation requires the derivative to “differ significantly in properties with regard to efficacy”. What is evident, therefore, is that not all advantageous or beneficial properties are relevant, but only such properties that directly relate to efficacy, which in case of medicine is its therapeutic efficacy.

13) In case of chemicals, 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 clauses (j) and (ja) of section 2(1), the test of enhanced efficacy as provided for in section 3(d), read with its Explanation. Beta crystalline form of Imatinib Mesylate failed in both the tests of invention and patentability as provided under clauses (j), (ja) of section 2(1) and section 3(d), respectively, and, thus, the appeals filed by Novartis AG failed and were to be dismissed with costs - Novartis AG v. Union of India [2013] 32 1 (SC)