Patent claim of Novratis in Supreme Court of India

Patent: definition of new product:

Questions before the Court:

  1. What is the true import of section 3(d) of the Patents Act, 1970? 
  2. How does it interplay with clauses (j) and (ja) of section 2(1)? 
  3. Does the product for which the appellant claims patent qualify as a new productwhich comes by through an invention that has a feature that involves technical advance over the existing knowledge and that makes the invention “not obvious” to a person skilled in the art?
  4. In case the appellant’s product satisfies the tests and thus qualifies as invention within the meaning of clauses (j) and (ja) of section 2(1), can its patentability still be questioned and denied on the ground that section 3(d) puts it out of the category of “invention”?

Section 3(d) of Patent Act, 1970:

(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.
Explanation.—For the purposes of this clause, salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations and other derivatives of known substance shall be considered to be the same substance, unless they differ significantly in properties with regard to efficacy;

Patent claim over imatnib3:

Facts of the case:
The appellant claims that beginning with Imatinib3 in free base form (as the educt), in a two-stage invention they first produced its methanesulfonic acid addition salt, Imatinib Mesylate, and then proceeded to develop the beta crystalline form of the salt of Imatinib. According to the appellant, starting from Imatinib free base they could reach to the beta crystal form of Imatinib Mesylate in two ways: one by digesting another crystal form, especially the alpha crystal form, or an amorphous starting material of the methanesulfonic acid addition salt of compound of formula I …”; and second by dissolving another crystal form, especially the alpha crystal form, or an amorphous starting material of the methanesulfonic acid addition salt of compound of formula I…”.
The appellant filed the application (Application No.1602/MAS/1998)1 for grant of patent for Imatinib Mesylate in beta crystalline form at the Chennai Patent Office on July 17, 1998. In the application it claimed that the invented product, the beta crystal form of Imatinib Mesylate, has (i) more beneficial flow properties: (ii) better thermodynamic stability; and (iii) lower hygroscopicity than the alpha crystal form of Imatinib Mesylate. It further claimed that the aforesaid properties makes the invented product new(and superior!) as it stores better and is easier to process; has better processability of the methanesulfonic acid addition salt of a compound of formula I, and has a further advantage for processing and storing.

It is significant to note that the comparison of the aforesaid properties of the beta crystal form of Imatinib Mesylate was made with its alpha crystal form. In the patent application, there is no claim of superiority of the beta crystal form of Imatinib Mesylate in regard to the aforesaid three properties, or any other property, over the starting material Imatinib, or even over Imatinib Mesylate in amorphous form or any form other than the alpha crystal form. On the contrary, insofar as Imatinib in free base form is concerned, it was unambiguously stated in the patent application as under:
It goes without saying that all the indicated inhibitory and pharmacological effects are also found with the free base, 4-(4-methylpiperazin-1-ylmethyl)-N-[4-methyl-3-(4-pyridin-3-yl) pyrimidin-2-ylamino)phenyl] benzamide, or other cells thereof. The present invention relates especially to the crystal form of the methanesulfonic acid addition salt of a compound of formula I in the treatment of one of the said diseases or in the preparation of a pharmacological agent for the treatment thereto.
After the application was made and before it was taken up for consideration, a number of amendments were introduced in the Indian Patents Act, 1970, which brought about fundamental changes in the patent law of the country. The appellant was, however, fully aware of these changes in the law ……..
The Assistant Controller held that the invention claimed by the appellant was anticipated by prior publication, i.e., the Zimmermann patent; that the invention claimed by the appellant was obvious to a person skilled in the art in view of the disclosure provided in the Zimmermann patent specifications; and further that the patentability of the alleged invention was disallowed by section 3(d) of the Act; and also that July 18, 1997, the Swiss priority date, was wrongly claimed as the priority date for the application in India and hence, the alleged invention was also anticipated by the specification made in the application submitted in Switzerland.
Patent application was made on July 17, 1998, giving July 18, 1997, the date on which the appellant had applied for grant of patent for the subject product in Switzerland, as the priority date. On July 18, 1997, Switzerland was not one of the Convention Countries as defined under section 2 (1)(d) read with section 133 of the Act and it was notified as a convention country as per section 133 of the Act on November 30, 1998.
The Assistant Controller held that the invention claimed by the appellant was anticipated by prior publication, i.e., the Zimmermann patent; that the invention claimed by the appellant was obvious to a person skilled in the art in view of the disclosure provided in the Zimmermann patent specifications; and further that the patentability of the alleged invention was disallowed by section 3(d) of the Act; and also that July 18, 1997, the Swiss priority date, was wrongly claimed as the priority date for the application in India and hence, the alleged invention was also anticipated by the specification made in the application submitted in Switzerland.
The IPAB (Intellectual Property Appellate Board) reversed the findings of the Assistant Controller on the issues of anticipation and obviousness. It held that the appellant’s invention satisfied the tests of novelty and non-obviousness, and further that in view of the amended section 133, the appellant was fully entitled to get July 18, 1997, the date on which the patent application was made in Switzerland, as the priority date for his application in India. The IPAB, however, held that the patentability of the subject product was hit by section 3(d) of the Act. Referring to section 3(d) the IPAB observed:
“Since India is having a requirement of higher standard of inventive step by introducing the amended section 3(d) of the Act, what is patentable in other countries will not be patentable in India. As we see, the object of amended section 3(d) of the Act is nothing but a requirement of higher standard of inventive step in the law particularly for the drug/pharmaceutical substances.”
Against the order of the IPAB the appellant came directly to Supreme Court in a petition under Article 136 of the Constitution.

Patent be determined on intrinsic worth of invention:

The subject product admittedly emerges from the Zimmermann patent. Hence, in order to test the correctness of the claim made on behalf of the appellant, that the subject product is brought into being through inventive research, we need to examine in some detail the Zimmermann patent and certain developments that took place on that basis

We are completely unable to see how Imatinib Mesylate can be said to be a new product, having come into being through an invention that has a feature that involves technical advance over the existing knowledge and that would make the invention not obvious to a person skilled in the art. Imatinib Mesylate is all there in the Zimmermann patent. It is a known substance from the Zimmermann patent.

 

That Imatinib Mesylate is fully part of the Zimmermann patent is also borne out from another circumstance. It may be noted that after the Zimmermann patent, the appellant applied for, and in several cases obtained, patent in the US not only for the beta and alpha crystalline forms of Imatinib Mesylate, but also for Imatinib in a number of different forms. The appellant, however, never asked for any patent for Imatinib Mesylate in non-crystalline form, for the simple reason that it had always maintained that Imatinib Mesylate is fully a part of the Zimmermann patent and does not call for any separate patent.

 

We thus find no force in the submission that the development of Imatinib Mesylate from Imatinib is outside the Zimmermann patent and constitutes an invention as understood in the law of patent in India.

The subject product admittedly emerges from the Zimmermann patent. Hence, in order to test the correctness of the claim made on behalf of the appellant, that the subject product is brought into being through inventive research, we need to examine in some detail the Zimmermann patent and certain developments that took place on that basis

 

We would like to say that in this country the law of patent, after the introduction of product patent for all kinds of substances in the patent regime, is in its infancy. We certainly do not wish the law of patent in this country to develop on lines where there may be a vast gap between the coverage and the disclosure under the patent; where the scope of the patent is determined not on the intrinsic worth of the invention but by the artful drafting of its claims by skilful lawyers, and where patents are traded as a commodity not for production and marketing of the patented products but to search for someone who may be sued for infringement of the patent.

In light of the discussions made above, we firmly reject the appellant’s case that Imatinib Mesylate is a new product and the outcome of an invention beyond the Zimmermann patent. We hold and find that Imatinib Mesylate is a known substance from the Zimmermann patent itself. Not only is Imatinib Mesylate known as a substance in the Zimmermann patent, but its pharmacological properties are also known in the Zimmermann patent and in the article published in the Cancer Research journal referred to above. The consequential finding, therefore, is that Imatinib Mesylate does not qualify the test of inventionas laid down in section 2(1)(j) and section 2(1)(ja) of the Patents Act, 1970.

On facts also we are unable to accept that Imatinib Mesylate or even Imatinib was not a known substance with known efficacy. It is seen above that Imatinib Mesylate was a known substance from the Zimmermann patent.

It further needs to be noted that, 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 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, thermodynamic stability and lower hygroscopicity).

It is to be noted that the higher solubility of the beta crystalline form of Imatinib Mesylate is being compared not to Imatinib Mesylate but, once again, to Imatinib in free base form. The whole case of the appellant, as made out in the subject application and the affidavits, is that the subject product, the beta crystalline form of Imatinib Mesylate, is derived from Imatinib, and that the substance immediately preceding the beta crystalline form is not Imatinib Mesylate but Imatinib in free base form. This position is sought to be canvassed in the subject application and the affidavits on the premise that the Zimmermann patent ended at Imatinib in free base and did not go beyond to Imatinib Mesylate. Not only is this premise unfounded as shown earlier, but the appellant itself appears to take a somewhat different stand, as before this Court it was contended that the subject product, in terms of invention, is two stages removed from Imatinib in free base, and the substance immediately preceding the subject product is Imatinib Mesylate (non-crystalline).

One does not have to be an expert in chemistry to know that salts normally have much better solubility than compounds in free base form. If that be so, the additional properties that may be attributed to the beta crystalline form of Imatinib Mesylate would be limited to the following:

i. More beneficial flow properties,

ii. Better thermodynamic stability, and

iii. Lower hygroscopicity

It is seen above that all the pharmacological effects of Imatinib Mesylate in beta crystalline form are equally possessed by Imatinib in free base form. The position is not only admitted but repeatedly reiterated in the patent application.

Mere change of form with properties inherent to that form would not qualify as enhancement of efficacy of a known substance. In other words, the explanation is meant to indicate what is not to be considered as therapeutic efficacy.

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, namely (i) more beneficial flow properties, (ii) better thermodynamic stability, and (iii) lower hygroscopicity, 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.

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 in vivo animal model.

Thus, in whichever way section 3(d) may be viewed, whether as setting up the standards of “patentability” or as an extension of the definition of “invention”, it must be held that on the basis of the materials brought before this Court, the subject product, that is, the beta crystalline form of Imatinib Mesylate, fails the test of section 3(d), too, of the Act.

(Emphasis added)

[Source: Novratis AG v. Union of India (Supreme Court of India)]
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