What is it?
It comes as GSK and Vir Biotechnology said preclinical data shows the drug “retains activity against key mutations of the new Omicron Sars-CoV-2 variant”.
What do scientists say it will do?
George Scangos, chief executive of Vir, said: “Sotrovimab was deliberately designed with a mutating virus in mind.
“By targeting a highly conserved region of the spike protein that is less likely to mutate, we hoped to address both the current Sars-CoV-2 virus and future variants that we expected would be inevitable.
“This hypothesis has borne out again and again, with its ongoing ability to maintain activity against all tested variants of concern and interest to date, including key mutations found in Omicron, as demonstrated by preclinical data.
“We have every expectation that this positive trend will continue and are working rapidly to confirm its activity against the full combination sequence of Omicron.”
The drug is the second monoclonal antibody treatment to be approved by the MHRA following Ronapreve.
Dr June Raine, MHRA chief executive, said: “This is yet another therapeutic that has been shown to be effective at protecting those most vulnerable to Covid-19 and signals another significant step forward in our fight against this devastating disease.”
How does it work?
The body said the drug works by binding to the spike protein on the outside of the Covid-19 virus.
This in turn prevents the virus from attaching to and entering human cells, so it cannot replicate in the body.
Based on the clinical trial data, the drug is most effective when taken during the early stages of infection.
As a result, the MHRA said it should be given as soon as possible and within five days of symptoms starting.
The drug has been approved for people who have mild to moderate Covid-19 infection and at least one risk factor for developing severe illness.
These include obesity, being 60 or over, diabetes or heart disease.
Xevudy is administered by intravenous infusion over 30 minutes and is approved for people aged 12 and over.
The MHRA said it was working with the company to establish effectiveness against Omicron.