A new form of a known substance can only be considered patentable provided the same demonstrates enhanced efficacy.

JUDGMENT :

Ravi Krishan Kapur, J.:

1. This is an appeal under section 117A of the Patents Act 1970 challenging an order dated 16 September 2021 passed by the Assistant Controller of Patents and Designs rejecting Patent Application No. 1879/KOLNP/2011 dated 5 May, 2011 filed by the appellant.

2. Briefly, the appellant is a biopharmaceutical company focused on discovery, development and commercialization of first-in-class pharmaceutical therapies to treat ocular surface diseases. The present invention relates to a stereospecific synthesis of (R)-5(E)-2-pyrrolidin-3-ylvinyl)pyrimidine, its salt forms, and novel polymorphic forms of these salts. The present invention also includes methods for treating a wide variety of conditions and disorders, including pain, inflammation, and conditions associated with dysfunction of the central and autonomic nervous systems.

3. The appellant had filed an application with claims 1-35 and Form 13 making voluntary amendments to claims 1-9 on 31 October 2017 and 22 October 2018 respectively. Subsequently, a First Examination Report (FER) was issued on 10 July 2019. A detailed reply to the FER was duly submitted by the appellants on 11 February 2020 alongwith a revised set of claims. Thereafter, a hearing notice was issued on 6 July 2020. The appellant had also submitted detailed Written Submissions along with further revised claims 1-5 on 11 September 2020.

4. By the impugned order, the respondent no.2 rejected the application citing three prior art documents being D1, D2 and D3 respectively. The grounds for rejecting the patent application were under sections 2(1)(ja) and 3(d) of the Act.

5. It is contended by the appellant that, the prior art D1 describes a number of different compounds including galactarate salt of (R)-5-((E)-2-pyrroliding-3-ylvinyl)pyrimidine. However, the same does not encourage a skilled person to focus on the compounds claimed in the subject invention nor does it render an obvious teaching of the advantageous properties of the claimed invention. It is contended that, (R)-5-((E )-2-pyrroliding-3-ylvinyl)pyrimidine in its free base form is a viscous oil with limited water solubility and stability. In order to commercialise the compound, it is necessary to discover means of formulating the compound to increase its stability, solubility and ease of manufacture which also enables accurate formulation and reproducible dosing. In such circumstances, it is contended that the respondents have failed to understand that the disclosure in the PCT specification demonstrates that the mono-citrate salt could be obtained in stable, free-flowing solid forms both amorphous and crystalline, not sensitive to moisture or temperature, nor is it hygroscopic and the same does not deliquesce upon stability testing. This conclusion could not have been arrived at without additional experiments being conducted by a person skilled in the art. Hence, obtaining a particular salt is not a routine process and the mere application of acids of D2 and D3 does not result in obtaining a pharmaceutically acceptable salt. In any event, there has been no discussion in the order as to how the subject patent application lacked inventive steps.

6. It is also contended that the respondents failed to consider the enhanced efficacy of mono citrate salt of (R)-5-((E)-2-pyrroliding-3-ylvinyl)pyrimidine which is evident from the amended set of claims 1-5 filed by the appellant post hearing and also from Appendix C. The amended set of claims conclusively prove the enhanced efficacy of the salt compound. It is also contended that respondent erred in not considering the additional experimental data supporting the claimed invention filed with the Written Submissions. In support of their contention, the appellant relies on Novartis AG vs Union of India (2013) 6 SCC 1 to contend that experimental data showing efficacy of a drug or a compound may be filed during the course of prosecution and the same should be considered.

7. On behalf of