UK is now the first country in the world to approve an oral antiviral that can be taken at home for Covid. US drug companies Merck, Sharp and Dohme (MSD) and Ridgeback Biotherapeutics developed Molnupiravir, the first antiviral medication for Covid which can be taken as a pill rather than injected or given intravenously.
The UK medicines regulator, the MHRA, has been approved the first pill designed to treat symptomatic Covid. The UK has agreed to purchase 480,000 courses with the first deliveries expected in November. The UK regulator said the tablet had been authorised for use in people who have mild to moderate Covid and at least one risk factor for developing severe illness such as obesity, old age, diabetes or heart disease.
Initially it will be given to both vaccinated and unvaccinated patients through a national study, with extra data on its effectiveness collected before any decision to order more.
The tablet – molnupiravir – will be given twice a day to vulnerable patients recently diagnosed with the disease. It is to be given within five days of symptoms developing to be most effective. The new treatment targets an enzyme that the virus uses to make copies of itself, introducing errors into its genetic code. That should prevent it from multiplying, so keeping virus levels low in the body and reducing the severity of the disease. Merck said that approach should make the treatment equally effective against new variants of the virus as it evolves in the future
In clinical trials the pill, originally developed to treat flu, cut the risk of hospitalisation or death by about half. The pill is gamechanger, because it can be administered outside of a hospital setting, before Covid-19 progresses to a severe stage.
Data suggest molnupiravir needs to be taken soon after symptoms develop to have an effect. The MHRA recommends the drug is used “as soon as possible” following a positive Covid test and within five days of symptoms onset. It is likely to be restricted for use by those at highest risk of disease complications – for example older adults with heart, lung or kidney disease, diabetes or cancer.
Merck is the first company to report trial results of a pill to treat Covid, but other companies like Pfizer has started trials of two different antiviral tablets and Swiss company Roche is working on a similar medication.