Merck & Co halts development of potential COVID-19 drug MK-7110

Merck & Co – known as MSD outside the US and Canada – has announced that it will discontinue development of its potential COVID-19 treatment MK-7110.

The company acquired MK-7110, a recombinant fusion protein, as part of its acquisition of OncoImmune in December 2020.

Following the acquisition, the US Food and Drug Administration (FDA) told Merck & Co that additional data, as well as a study already conducted by OncoImmune, would be required to support a potential emergency use authorisation application for MK-7110.

Merck & Co said that the additional research required would mean that MK-7110 would not become available until the first half of 2022.

The timescale for potential clinical development, coupled with technical, clinical and regulatory uncertainties have factored into Merck & Co’s decision to discontinue the MK-7110 programme for patients hospitalised with COVID-19.

The company also highlighted other reasons for the decision, including the availability of other medicines for hospitalised COVID-19 patients.

“Merck is now focusing its efforts on advancing molnupiravir, which, as an oral medicine for outpatient use, represents a promising potential new approach, and on accelerating production of Johnson & Johnson’s COVID-19 vaccine,” said Roy Baynes, senior vice president and head of global clinical development, chief medical officer, Merck Research Laboratories.

Also this week, Merck & Co and its development partner Ridgeback Therapeutics said the clinical development of its investigational COVID-19 antiviral therapy molnupiravir in hospitalised patients with COVID-19 would not progress to phase 3.

However, the companies also announced that another study of the antiviral therapy in the COVID-19 outpatient setting, would proceed to phase 3, based on a planned interim analysis of data from the phase 2 portion of the trial.

Merck & Co and Ridgeback previously reported some promising results for molnupiravir in a phase 2a trial evaluating the drug’s safety, tolerability and efficacy in eliminating SARS-CoV-2 viral RNA in non-hospitalised adults who had signs or symptoms of COVID-19.

According to the early data, presented at the 2021 Conference on Retroviruses and Opportunistic Infections, molnupiravir led to a 'quicker decrease in infectious virus among individuals with early COVID-19'.

At day five of molnupiravir treatment, there was a reduction in positive viral culture in subjects who received the experimental drug compared to placebo – 0% for molnupiravir and 24% for placebo.