Covid-19: UK becomes first country to authorise antiviral molnupiravir

The UK’s medicines regulator has issued temporary authorisation of the antiviral drug molnupiravir for the treatment of mild to moderate covid-19 in adults with at least one risk factor for severe illness.1

The Medicines and Healthcare Products Regulatory Agency is the first regulator in the world to approve the drug, of which the UK has ordered 480 000 courses.

Molnupiravir will be rolled out to the people most at risk of covid-19, with the aim of reducing symptom severity and easing pressure on the NHS over winter, the Department of Health and Social Care for England has said.2

Interim phase III trial results, released through a press release by the drug’s manufacturer, MSD, found that molnupiravir reduced the risk of admission to hospital or death by around 50% in non-hospitalised adults who had mild to moderate covid-19 and were at risk of poor outcomes.3

The release said that 7.3% of patients (28 of 385) who received molnupiravir and 14.1% of those taking placebo (53 of 377) either were admitted to hospital or had died by day 29 after randomisation. At day 29 no deaths were reported in the molnupiravir group, while eight were reported in the placebo group. Recruitment to the trial was then stopped on the advice of the independent data monitoring committee because of the positive results.

The US has ordered 1.7 million courses of molnupiravir, and MSD said it also had plans to ensure that the treatment could be accessed by low and middle income countries. This includes a tiered pricing approach, based on World Bank country income criteria, and non-exclusive voluntary licensing agreements with established manufacturers of generic drugs to accelerate availability in more than 100 low and middle income countries.

Penny Ward, an independent pharmaceutical physician who advises drug companies on drug and device development, said that if the results from the clinical trial were replicated in the UK population then molnupiravir could halve the number of people needing hospital admission and greatly reduce deaths.

She added, “The NHS has yet to inform us on how this product may be distributed to patients; comments made by [health secretary] Mr Javid today suggest that it may be made available via a clinical trial, presumably to investigate its effectiveness in vaccinated patients with breakthrough infections, as the original study incorporated unvaccinated adults. In addition, as the UK has ordered 480 000 treatment courses, if given to everyone becoming unwell this supply would not last very long given the 40 000-plus current daily case rate. For this reason it seems likely that use will be restricted for use by those at highest risk of disease complications, such as older adults with heart, lung, or kidney disease, diabetes, or cancer.”