A new monoclonal antibody cocktail has been authorised by the Medicines and Healthcare products Regulatory Agency (MHRA) for the prevention of COVID-19.
Evusheld (AstraZeneca) is a combination of two monoclonal antibodies — tixagevimab and cilgavimab — and works by binding to the spike protein of the SARS-CoV-2 virus, preventing it from attaching and entering human cells.
The authorisation permits the use of Evusheld as a pre-exposure prophylaxis, to be given before individuals are exposed to the risk of COVID-19 infection.
It is approved for use in adults who are unlikely to mount an immune response from COVID-19 vaccination or for whom vaccination is not recommended.
A single dose of the two medicines will be administered as two intramuscular injections. Recipients of the treatment should not be currently infected with, or had recent known exposure to a person infected with, COVID-19.
The decision to grant the approval was endorsed by the Commission on Human Medicines, the government’s independent expert scientific advisory body, following a review of the available evidence.
In a clinical trial in adults, published in December 2021, Evusheld was found to reduce the risk of developing symptomatic COVID-19 by 77%, with protection from the virus continuing for at least six months following a single dose.
It is not yet known how effective the treatment is against the Omicron variant.
June Raine, chief executive of the MHRA, said: “Evusheld is the first monoclonal antibody treatment to be approved as a ‘pre-exposure prophylaxis’ treatment, meaning it is taken to prevent COVID-19 before the risk of acquiring infection.
“One dose has been found to provide long-lasting protection against this disease for up to 6 months,” she added.
“While the COVID-19 vaccines continue to be the first-line defence against COVID-19, we know that some people may not respond adequately to these vaccines and for a small number of individuals COVID-19 vaccines may not be recommended for other reasons, such as a previous allergic reaction to one of the vaccine ingredients.
“For these people, Evusheld could provide effective protection against COVID-19.”
Sir Munir Pirmohamed, chair of the Commission on Human Medicines, explained that the recommended dosage of the treatment was 300mg of Evusheld, but a higher dose of 600mg may be “more appropriate” for some COVID-19 variants.
“All this is outlined in the summary of product characteristics,” he added.
“Pre-exposure prophylaxis with Evusheld is not a substitute for vaccination in individuals for whom COVID-19 vaccination is recommended.”
Penny Ward, visiting professor in pharmaceutical medicine at King’s College London, said that Evusheld could help vulnerable people, who may be still shielding, return to a normal life.
“This treatment could therefore be a good way to protect patients who are not able to respond normally to vaccination and allow this group to be able to return to a more normal life than they are currently able to enjoy.”
Other monoclonal antibody treatments have been approved for COVID-19, including sotrovimab, but these are approved for people with mild-to-moderate COVID-19 and at least one risk factor for developing severe illness, rather than as pre-exposure prophylaxis.