The United States has signed contracts worth about $1 billion for doses of the antibody-based COVID-19 treatment from Britain's GSK and US-based Vir Biotechnology, as countries seek to secure promising options beyond vaccines.
The drugmakers said on Wednesday the US orders bring the total number of doses to be supplied to more than 750,000 globally, without specifying how many doses of the treatment, sotrovimab, the US government had signed up for.
However, other public deals for the drug include 10,000 doses for Canada and up to 220,000 doses for the European Union. Values of those orders have not been disclosed.
US deliveries of the treatment, branded Xevudy, are expected by December 17 and the government will also have an option to buy more doses through March 2022, GSK and Vir said in their joint statement.
While vaccines remain at the heart of the long-term fight against the COVID-19 pandemic, treatments including game-changing antiviral pills from Merck and Pfizer, offer options to contain infections and save lives.
Pfizer said on Tuesday it was seeking US authorization of its experimental antiviral COVID-19 pill that cut the chance of hospitalization or death for adults at risk of severe disease by 89% in a clinical trial.
GSK-Vir's sotrovimab has shown to reduce that risk by 79% in trials.
Unlike oral options from Merck and Pfizer, sotrovimab is given via an infusion. It belongs to a class of medicines called monoclonal antibodies which are lab-generated compounds that mimic the body's natural defences.
The therapy was authorized for emergency use in the United States in May to prevent mild or moderate cases of COVID-19 from worsening. The European regulator has given its go-ahead for use by member states, although EU-wide approval is still pending.
"Given ongoing evidence, which demonstrates its ability to maintain activity against the tested circulating variants of concern, including Delta, we are confident sotrovimab will continue to be important," Vir Chief Executive George Scangos said.
Last week, GSK and Vir said the antibody treatment was shown in a trial to work as well when given as a shot in the arm when administered via the standard infusion, potentially offering more convenience.
Sotrovimab brought in sales of 130 million pounds ($175 million) for GSK in the first nine months of 2021.
Similar products are offered or being developed by Eli Lilly, Regeneron, AstraZeneca and Celltrion.
Last month US authorities said the government would control distribution of sotrovimab in the country.