Rejecting Pre-Grant Opposition, IPO Grants Patent to Gilead’s HIV Drug Cobicistat

The India Patent Office on February 24, 2020 granted a patent to Cobicistat, a drug for use in HIV and AIDS, of a US based biopharmaceutical company Gilead Sciences, rejecting a pregrant opposition filed by a non-profit organization – Uttar Pradesh Welfare for People Living with HIV/AIDS Society (UPNPplus).

In 2008, the US based biopharmaceutical company Gilead Sciences (hereinafter Applicant) filed a patent application on Cobicistat, a drug for use in HIV and AIDS, claiming priorities from three US patent applications filed in 2006 and 2007. During prosecution, in 2013, Cipla Limited filed a pre-grant opposition against the Cobicistat application and in 2018 the said opposition was withdrawn before a scheduled hearing. Later in 2015, a non-profit organization – Uttar Pradesh Welfare for People Living with HIV/AIDS Society (UPNPplus) filed another pre-grant opposition against the Cobicistat under section 25(1) of the Indian Patent Act.

In the pre-grant opposition against the Cobicistat application, UPNPplus indicated that the subject matter lack inventive step, doesn’t satisfy the test of section 3(d) of the Patents Act as the subject matter does not exhibit enhanced therapeutic efficacy, and doesn’t satisfy the test of section 3(e) of the Patents Act as the subject of invention to be essentially used in combination with another therapeutic agent does not result in synergistic effect, however, it is a mere admixture resulting only in the aggregation of the properties of the components. Specifically, UPNPplus argued that the drug Cobicistat is a derivative of Ritonavir which is another anti-ritroviral medication used in combination to treat HIV/AIDS, and hence the invention is not patentable under section 3(d) of the Patent Act.

Section 3(d) of Indian Patent Act:

The Indian Patent Act stipulates that the new forms of known substance should demonstrate that the new forms enhance the therapeutic efficacy of the substance in order to deserve a patent. This provision, Section 3(d), was designed to prevent extension of a patent life of a drug by obtaining additional 20 years rights for minor reformulations or other iterations of the drug, without necessarily increasing the therapeutic efficacy.

Gilead’s Submission non-patentability under Section 3(d):

Post hearing, Gilead submitted the drug Cobicistat is not a mere discovery of a new form of a known substance, however, Cobicistat is a New Chemical Entity (NCE) and it does not employ Ritonavir as a starting material. Gilead states the drug Cobicistat is obtained through an elaborate multi-step synthesis process, not by removal of Ritonavir’s central hydroxyl function. Further, the drug is a potent and selective inhibitor of enzymes without exhibiting any appreciable biological activity of its own and lacks significant HIV-1 protease inhibitory activity.

Decision:

The Assistant Controller of patents and designs, after considering arguments from UPNPplus and Gilead, rejected the pre-grant opposition and granted a patent to Cobicistat on 24th February 2020, stating that the invention does not fall within the scope of Section 3(d) of the Patents Act as the drug Cobicistat is not a derivative of Ritonavir in view of structural differences between Cobicistat and Ritonavir and the differences in structure cannot be considered as mere structural modification carried out as part of development of derivatives of Ritonavir.


Rejecting Pre-Grant Opposition, IPO Grants Patent to  Gilead’s HIV Drug Cobicistat by Prasanna Hegde

Article was 1st published on Lexology.