Roche vs. Cipla marks the end of the first phase of a key battle between big pharma and the Indian generic industry. The infringement action brought by Roche against Cipla and Cipla's counterclaim for Roche's patent invalidity was both dismissed.

Roche was granted Indian Patent No. IN '774 in February 2007, under which per Claim 1, they had patent rights over the Erlotinib Hydrochloride (EH) molecule (which has demonstrated breakthrough capabilities as an Epidermal Growth Factor Receptor (EGFR) inhibitor which spiked survival benefit in non-small cell lung cancer (NSLC) patients). Based on media reports declaring Cipla's intention to launch a generic version of Roche's drug in January 2008, Roche moved the Delhi High Court seeking to injunct Cipla from marketing Erlocip. Cipla counterclaimed, arguing that Roche's patent was invalid. The judgment deals with two key issues:

[1] Whether the manufacture of Erlocip infringes Roche's IN '774 patent and

[2] Whether Roche's IN '774 patent ought to be revoked as being invalid.

The court concluded that -

  1. The manufacture, marketing and sale of Cipla's generic version of the Roche's patented product do not infringe Roche's Indian Patent 196774.
  2. Roche's Indian Patent 196774 is valid against the grounds raised by Cipla in its written statement and counter-claim.
  3. A permanent injunction is denied to Roche.
  4. The counter-claim proves that Roche's subsequent US Patent 6900221 is directed at the compound of claim No.1 of the suit patent is a mixture of the two, Polymorph A and B Compound and need to be separated to perform and get the claimed compound for acceptable efficacy.

The Infringement question: –

The relief claimed, however, was for infringement of rights in the drug Tarceva as well as an injunction restraining the manufacturing and marketing Erlocip. Cipla's defence to Roche's infringement claim was that IN '774 is for an admixture of Polymorphs A and B of EH but Tarceva is the stable form of Polymorph B, which corresponds to US '221 (and the rejected IN '507) and that the same was not covered by 'IN 774, and hence there can be no infringement. Roche argued that Cipla's drug was also EH and manufacture of Polymorph B by Cipla was sufficient to trigger infringement of Claim 1 of IN '774 on the premise that any process involved in making Polymorph B would first involve the preparation of a combination of Polymorph A and B.

This led the court to construe Claim 1 of IN '774 to examine whether it subsumes Polymorph B of Erlotinib Hydrochloride, which is admittedly Erlocip. The court while placing reliance on expert testimony adduced by Cipla, went on for a purposive claim interpretation as an aid which advocates giving effect to 'the real purpose for which the product was invented'. Lastly, on the basis of US '221 specification which attest Polymorph B as the sole efficacious expression of Erlotinib Hydrochloride and by the fact that Roche's application for IN '507 cuts through IN '774, the court held that:

"In [the] absence of the explanation of the said role either as a major or minor reactants coupled with the fact that both in India as well as in [the] US, the [P]laintiffs have applied for the patent for the said process and product separately than the underlying compound, the purposive construction of the claim and the specification of IN '774 clearly indicates that the said [P]laintiffs did not intend to include the Polymorphic version B in the suit patent IN '774".

This makes it clear, according to the court that Tarceva did not correspond with that of the patent and therefore there was no infringement of the legal rights of Roche.

The Validity question –

Cipla's counterclaim contended that IN '774 contains no inventive step and is not novel for two reasons – first, IN '774 specification is silent on how is it an advancement over the closest prior art which is Example 51 of EP '226; and second, the difference between IN '774 and Example 51 of EP '226 with respect to the substitution of a methyl group with ethynyl at the third meta (3') position is obvious to a person skilled in the art on account of at least five prior art teachings which suggest that methyl and ethynyl can be used interchangeably with no categorical loss of efficacy.

In response, Roche argued that comparative efficacy in this case had been mapped according to inhibitory concentration (which term can be loosely understood as the concentration of a substance that causes a defined inhibition of a system), in which respect IN '774 is closest to a prior art reference EP '851 and is also inventive over it. Consequently, they saw no reason why EP '226 (and Example 51 specifically, which does not display an inhibitory concentration value within even the top five such values of compounds disclosed by EP '226) should be treated as the point of departure in the inventive step analysis. Indeed, EP '226 teaches a methyl/ethynyl substitution at the 6, 7- position and not at the 3' position and there are several demonstrable differences in bond angle, bond length and bond strength and the type of reaction with EGFR kinase between methyl and ethynyl group that make the substitution ostensibly inventive.

The court, in addition to the absence of any positive evidence by Cipla in establishing obviousness, procedurally disregarded the five patent specifications cited by Cipla to show that methyl/ethyl substitution was well known in prior art because they were filed after framing of issues and did not meet the requirement that they could not be filed on account of being outside Cipla's knowledge or resources.

Cipla's challenge to the validity of the impugned patent on it being attracted by section 3(d) did not find favour with the court on account of Cipla failing to meet the positive evidence onus to sustain that challenge. The court observed that Cipla had to prove that IN '774 is the 'new form of an old substance' (the 'old substance' being EP '226) and that Example 51 of EP '226, through further reaction, can result in IN '774 is insufficient to establish 'new form of an old substance' unless proven to be contrary, which none of their witnesses deposed.

On an overall consideration of factors, the court held that Cipla was unable to meet even a balance of probabilities to establish revocation.

Lastly, The Roche v Cipla judgment on Section 8 of the Patents Act 1970 which lays down disclosure requirements as to all corresponding foreign patent applications and pursuant to a decision in Chemtura Corporation v Union of India,which laid down a strict threshold of disclosure and also warned that inadequacy of disclosure would be a ground to seek revocation of a patent, does not refer to Chemtura but categorically does not revoke IN '774 despite holding on facts that "...the plaintiffs as patentee has not disclosed the information as required by the controller as per Section 8 of the Act which is evident upon from the examination report dated 22.8.2006 and the responses thereto which do not record the subsequent patent in US'221 which ought to have been disclosed. Thus the ground of revocation under Section 64 (1) (m) is made out". Despite holding that the ground under Section 64 (1) (m) is made out the court chooses to exercise positive discretion in the plaintiff's favour to not revoke the patent by inferring the existence of such discretion from the presence of the word "may" in the Section. This observation will undoubtedly afford a respite to patentees who have been find it challenging to meet with Section 8 obligations and thus being faced with revocation of substantively valid patents on account of inadequacy of disclosures under Section 8.

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