What you need to know about new Covid-19 treatment sotrovimab - and how it works
Xevudy, also known as sotrovimab, was found to be “safe and effective at reducing the risk of hospitalisation and death” following “a rigorous review of its safety, quality and effectiveness by the UK regulator”.
This is what you need to know.
What is sotrovimab?
Sotrovimab, which was developed by GSK and Vir Biotechnology, is something called a “single monoclonal antibody”.
It works by attaching itself to the spike protein on the outside of the Covid-19 virus which in turn prevents the virus from attaching to and entering human cells, and therefore cannot replicate in the body.
In a clinical trial, it was found that a single dose of sotrovimab was found to reduce the risk of hospitalisation and death by 79% in high-risk adults with symptomatic Covid-19 infection.
In the announcement, the Government emphasised that sotrovimab is “not intended to be used as a substitute for vaccination against Covid-19” and that the Government and the NHS “will confirm how this Covid-19 treatment will be deployed to patients in due course”.
Sotrovimab is the second monoclonal antibody therapeutic to be approved following Ronapreve, which was approved at the end of August of this year.
When is sotrovimab most effective?
Based on the drug's clinical trial data, sotrovimab is found to be most effective when it is taken during the early stages of infection. The MHRA recommends that it is used as soon as possible, and within five days of symptom onset.
Much like molnupiravir, which was authorized for use in early November, sotrovimab has been approved for use in cases of mild to moderate Covid-19 infection and “at least one risk factor for developing severe illness”.
The Government states that these risk factors include things like obesity, older age (>60 years), diabetes mellitus and heart disease.
Unlike molnupiravir, which is taken orally, sotrovimab is administered via intravenous infusion over the course of 30 minutes.
It has been approved for people over the age of 12 and who weigh more than 40kg.
Is it effective against the omicron variant?
In the statement from the Government, it is said that “it is too early to know whether the omicron variant has any impact on sotrovimab’s effectiveness but the MHRA will work with the company to establish this”.
However, George Scangos, Chief Executive of Vir, said that sotrovimab was “deliberately designed with a mutating virus in mind”.
He said: “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.”
What has the Government said about the drug?
In the announcement from the Government stating that the MHRA has approved sotrovimab, MHRA Chief Executive, Dr June Raine, said: “I am pleased to say that we now have another safe and effective Covid-19 treatment, Xevudy (sotrovimab), for those at risk of developing severe illness.
“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.
“With no compromises on quality, safety and effectiveness, the public can trust that the MHRA have conducted a robust and thorough assessment of all the available data.”
Professor Sir Munir Pirmohamed, Chair of the Commission on Human Medicines, also said:“The Commission on Human Medicines and its Covid-19 Therapeutics Expert Working Group has independently reviewed the data and agrees with the MHRA’s regulatory approval of Xevudy (sotrovimab).
“When administered in the early stages of infection, sotrovimab was found to be effective at reducing the risk of hospitalisation and death in high-risk individuals with symptomatic Covid-19.
“Based on the data reviewed by the Commission and its expert group, it is clear sotrovimab is another safe and effective treatment to help us in our fight against Covid-19.”