Merck & Co Inc (NYSE:MRK) has released new data on its COVID antiviral tablet that suggests it is not as effective as originally hoped.
Research from its MOVe-OUT study of the drug, named Molnupiravir, found that it only reduced the risk by roughly 30% in adults at high risk for disease progression.
Some 1433 people took part in the trial, with 699 given a placebo and 709 the medication.
Of those who took the placebo 9.7% became seriously ill, while the percentage was at 6.8% for those given the medication, representing a relative risk reduction 30%.
Previously, the company had reported a relative risk reduction of 48%.
READ: Merck Covid-19 treatment approved in UK as infection rate soars
Merck, which is partnered with Ridgeback Therapeutics on the drug, was upbeat nonetheless and said it was confident that the outcomes “support the efficacy and overall favourable benefit-risk assessment of Molnupiravir for the treatment of mild to moderate COVID-19 in adults.”
Merck confirmed that it has provided this analysis to the Food and Drug Administration with a review set to take place by the committee next Tuesday.
The drug has already been approved in the UK, with Britain agreeing a deal to secure 480,000 courses last month.
Merck shares fell by 4.28%.