The United States on Wednesday authorized Pfizer antiviral COVID-19 pill for at-risk people aged 12 and above, making it the first oral treatment and which can be taken at home, providing a potentially important tool in the fight against the fast-spreading Omicron variant.

Pfizer's antiviral regimen, Paxlovid, was nearly 90% effective in preventing hospitalizations and deaths in patients at high risk of severe illness, according to data from the company's clinical trial. Recent lab data suggests the drug retains its effectiveness against Omicron, Pfizer said. 

The company said it was ready to start immediate delivery in the US and raised its production projections to 120m courses of treatment from 80m in 2022.

The US government’s contract for 10 million courses of the Pfizer drug is priced at $530 per course.

Pfizer’s pills, taken with the older antiviral drug ritonavir, will be sold under the brand name Paxlovid.

The pills are meant to be taken every 12 hours for five days beginning shortly after the onset of symptoms.

Pfizer said it plans to file a new drug application with the FDA in 2022 for potential full regulatory approval.