Roche Holding has completed early tests of its ability to produce large quantities of Regeneron Pharmaceuticals' Covid-19 antibody treatment, putting it on track to begin manufacturing the drug once it's authorised by regulators, Regeneron has said.
The experimental therapy was used to treat United States President Donald Trump the previous month.
The companies aim to be able to make two million doses of the antibody cocktail next year, but are awaiting clearance from regulators.
Roche "has already started engineering runs at scale and (has) been successful", Regeneron president and chief scientific officer George Yancopoulos said in an interview on Tuesday, ahead of this week's Reuters Total Health conference.
A Roche spokesman said the Swiss drugmaker would be ready to begin producing the treatment in the first quarter of next year.
Regeneron has had discussions with the US Food and Drug Administration nearly every day since it submitted its application for emergency use of the Covid-19 drug the previous month, and expects a final decision in the "very near future", Mr Yancopoulos, a co-founder of the US biotech company, said.
Regeneron hopes to apply for full approval of the drug shortly afterwards, he said, echoing his comment during Regeneron's investor call earlier this month.
The company has a contract to provide 300,000 doses of the antibody therapy, called REGN-COV2, to the US government and expects to be able to meet that commitment by as early as January. It's more than 50,000 doses currently stockpiled.
The two million doses Regeneron expects to be able to produce in partnership with Roche next year may not be enough to treat all the patients worldwide who could benefit from it, Mr Yancopoulos said, based on the rate at which the virus is again spreading and sickening people globally.
He added that Regeneron is in talks with US officials about providing more doses than it's already agreed to, but has not reached any conclusive agreement.
Regeneron's current contract with the US government priced 300,000 doses at US$450 million (S$604 million).
Regeneron has been speaking regularly with US President-elect Joe Biden's Covid-19 task force and has shown them a presentation on the antibody treatment, Mr Yancopoulos said.
After Mr Trump received the Regeneron treatment along with several other medicines during his bout with Covid-19, he touted it as a virtual "cure" for the illness, promising to make it free for Americans.
REUTERS