Merck’s Covid-19 pill shows lower efficacy in updated data

Merck & Co said on Friday updated data from its study on its experimental Covid-19 pill showed the drug was significantly less effective in cutting hospitalisations and deaths than previously reported.

The drugmaker said its pill showed a 30% reduction in hospitalisations and deaths, based on data from over 1,400 patients. In October, its data showed a roughly 50% efficacy, based on data from 775 patients.

Merck released the data before the US Food and Drug Administration published a set of documents on Friday intended to brief a panel of outside experts who will meet on Tuesday to discuss whether to recommend authorising the pill.

The agency’s staff did not make their own recommendation as to whether the pill should be authorised.

FDA staff asked the panel to discuss whether the benefits of the drug outweigh the risks and whether the population for whom the drug should be authorised should be limited.

They also asked the committee to weigh in on concerns over whether the drug could encourage the virus to mutate, and how those concerns could be mitigated.

Merck’s shares fell 2.8% to US$80 in premarket trading, amid a fall in the broader markets.

Pills such as Merck’s drug molnupiravir and a rival drug being developed by Pfizer Inc have been touted as potential game-changers as they can be taken as early at-home treatments to help prevent hospitalisations and deaths.

Data from Pfizer’s pill, following analysis of a study involving 1,200 participants, showed an 89% reduction in the risk of coronavirus-related hospitalisations or deaths compared with a placebo.

Merck filed for a US authorisation of molnupiravir on Oct 11, following the interim data.

The company said on Friday that data on the drug, developed with Ridgeback Biotherapeutics, had been submitted to the FDA ahead of the meeting.

The molnupiravir arm of the study had a hospitalization and death rate of 6.8%, according to the updated data. The placebo group had a hospitalization and death rate of 9.7%.

One patient in the molnupiravir arm died, versus nine in the placebo group.