Indian Patent Office: Merck’s patent application for HIV drug, raltegravir, is “refused”

A patent that Merck has been pursuing in India since 2007 has been refused by the Indian Patent Office. The original claims to the patent lacked patentability criteria, and the company’s reasons for deciding to no longer the pursue the matter are vague.

The patent application for a potassium salt version of raltegravir was first applied for by Merck back in 2007. A number of oppositions were made, as the ‘inventive step’, one of key criteria required in obtaining a legitimate patent, was found to be lacking, and the claims being made by Merck were viewed as ‘obvious’.

Merck responded by making 13 revised claims, keeping the patent application alive up until last month. A further three patent oppositions (POs) were received by the patent office, including one submitted by our partner, the Delhi Network of Positive People (DNP+).

Merck failed to respond to the three additional POs within the three month period stipulated by Indian patent law, and the company’s attorney informed the examiner that the “applicant [Merck] is not keen on pursuing the present matter”.

“The company has not revealed why it made this decision, so we can only speculate,” says Loon Gangte, DNP+ co-founder and director, and ITPC’s regional coordinator for South Asia.

Precedent set: Unpatentable in Europe

Anand Grover, eminent Indian lawyer, shares his theories on what may have influenced Merck’s decision: “In 2017, the European patent for raltegravir was revoked. It was invalidated due to a lack of inventive step, and it was agreed that any person skilled in the art could derive at the formula for raltegravir, directly and unambiguously, using common general knowledge. This set a precedent, and indeed mirrors the claims opposing the patent in India. As a result, perhaps Merck thought that it wouldn’t be worth pursuing in India, a country with a strong track record in challenging unmerited monopolies” says Grover.

The patent oppositions submitted state that: the selection of potassium salt; the process of synthesising a salt; the salt formulation; salt screening and selection, all lack inventive step.
This is backed up by multiple evidence. Research, cited by the opposing parties, goes back as far as 1977 and as recently as 2004.

Bad PR

Grover outlines another possible motivation for Merck to back down: “Merck has agreed a license for the pediatric version of the same drug with the Medicines Patent Pool (MPP). It’s possible that the company considered that it wouldn’t be wise from a marketing position to continue to pursue the patent, as continuing to lay claim could undermine the company’s ‘good PR’.”

A shrinking ‘market’?

Raltegravir has been commonplace as a third-line HIV treatment in India. Now, dolutegravir is replacing raltegravir in third-line regimens in India, so the ‘market share’ is shrinking compared with when Merck first submitted its potassium salt application. This in itself could also provide an insight to boardroom decisions. Having benefitted from the application for 13 years, while there was greater potential for profit, perhaps current financial projections no longer make it worthwhile to pursue from a shareholder perspective.

Refused and discarded

In conclusion to the claims, oppositions, and evidence provided to the patent office, along with Merck’s eventual lack of contention, the patent office concluded: “In view of the above said existing objection, the instant Patent Application does not meet the requirement of the Act hence cannot be allowed. Accordingly the instant Patent Application is refused.”