Patient organizations gained a victory in their fight for access to medicines as Roche’s patent on Valganciclovir, an antiviral medication was revoked by the Chennai Patent Office. But this long drawn fight is not a clear victory since the patent term expired almost simultaneously.
Roche filed a patent application (959/MAS/1995) with the Indian Patent Office on 27 July 1995, covering Valganciclovir and its salts as well as a process for preparing the same. Valganciclovir is an oral prodrug of Ganciclovir that is used in the treatment of cytomegalovirus infections, primarily in immunocompromised patients such as HIV/AIDS patients or patients who have undergone organ transplants. The drug is prohibitively expensive costing around 2.7 lakhs for one course of treatment of a patient.
A pre-grant opposition was filed in Dec 2006 by patient organizations including Indian network for people living with HIV/AIDS (INP+) & The Tamilnadu networking people with HIV/AIDS (TNNP+) which was rejected by the Chennai patent office without giving an opportunity for the opponents to present their arguments. In a June 2007 order, the Chennai Patent Office granted the patent to Roche (IN207232) but the grant order was quashed and set aside by the Chennai High Court, which ordered that the arguments by the opponents be heard by the patent office. The Chennai patent office went ahead with the hearings but refused to hear all the arguments presented by the opponents and subsequently rejected the pre-grant opposition and granted the patent to Roche in January, 2009.
INP+ and TNNP+ then joined a post-grant opposition that was already filed by generic companies such as Ranbaxy, Cipla, Bakul Pharma and Matrix Labs along with another patient organization, Delhi network of positive people (DNP+). After the opposition proceedings, the Controller of Patents, in an order dated 30 Apr 2010, held the product claim on Valgonciclovir to be invalid and further limited the patent to a single process claim. On Roche’s appeal with IPAB, the board, in its order dated 30 Jan 2014, set aside the 30 Apr 2010 order and remanded it to the controller for reconsideration. The IPAB refused to accept Roche’s demand to restore the patent during the reconsideration.
Recent revocation order:
The controller of patents, in the order dated 1st July 2015 considered different issues before arriving at the decision to revoke the patent. On the role played by expert evidences to assess patentability, the order stated that expert evidences providing prior art analysis are not impartial documents. They cannot be considered as prior publications/ disclosures but can be taken only as an opinion on prior arts. Such expert evidences do not have a significant role in deciding patentability. Considering and relying on an expert opinion to assess patentability depends upon the particular case in question.
For deciding on the question of obviousness, the controller had considered two prior arts – EP0375329 (EP’329) and US4957924 (US’924). Valganciclovir claimed by Roche is a L-monovaline ester of Ganciclovir and provides a solution of improved oral bioavailability. The prior art EP’329 is directed to the preparation of bis-L-valinate ester of ganciclovir and discloses and claims monovaline ester also. Though the document does not explicitly disclose preparation of monovaline ester, it gives a general method of preparation of esters and a person skilled in the art can easily prepare monovaline esters using that method. The prior art US’924 solved the problem of poor oral bioavailability of Acyclovir, a compound having similar core structure like ganciclovir. The solution was to esterify Acyclovir with L-valine, wherein the oral bioavailability is much improved. A person skilled in the art could easily arrive at the same solution for improving oral bioavailability of ganciclovir through the teachings of US’924. Hence the controller concluded that all the claims of Roche’s patent on Valganciclovir including process claim are obvious to a person skilled in the art and hence the patent does not meet the non-obviousness criterion required for patentability.
As per the requirement of enhanced efficacy for a new form of a known substance, as given in section 3(d) of the Indian Patents Act, Valganciclovir should have enhanced efficacy when compared with ganciclovir. The revocation order when considering the point of enhanced efficacy states that, “Bioavailability is one of the factors for affecting efficacy but, it cannot be always directly equated to efficacy. Pharmacological study report shall be shown with results as evidence for significant enhancement in efficacy through the improved bioavailability”. Though Valganciclovir has improved bioavailability than ganciclovir and the bis-valine ester of ganciclovir, the controller has concluded that the specification of the impugned patent provides no support for enhanced efficacy. Hence, the substance Valganciclovir falls under the unpatentable subject matter. Also, the method of preparation of Valganciclovir is considered as “a mere use of a known process”.
Another point of contention raised by Roche was that the patient organizations do not fall under the category of “person interested” as defined by the Patents Act. According to S. 2(1)(t) of the Patents Act, “person interested” includes a person engaged in, or in promoting, research in the same field as that to which the invention relates”.
The controller noted that the Act provided a narrow opening to let an user/sufferer to oppose patent grant other than a person engaged in the same field and in the present case, S.2(1)(t) should be viewed in a broader perspective. The order thus concluded that the patient organizations have the locus standi to oppose the impugned patent.
Based on the above discussed issues, the controller revoked the grant of patent on Valganciclovir under section 25(4) of the Indian Patents Act. But as mentioned in the beginning, it is a victory that is gained a little too late.