Pfizer says pill is effective in protecting against severe disease from Covid

A pill manufactured by the prominent Covid-19 vaccine provider Pfizer is highly effective in protecting against severe disease from coronavirus, the company said on Tuesday.

The experimental antiviral pill Paxlovid is also effective against the Omicron variant that is spreading rapidly across the world, the company announced, citing laboratory testing.

In clinical trials, Paxlovid showed almost 90% efficacy in preventing hospitalization and death in high-risk patients, Pfizer stated, replicating the results of a smaller-scale trial announced last month.

Those results prompted the company to seek authorization from the US Food and Drug Administration (FDA) for the pill to become the first widely available oral medicine to combat coronavirus.

Regulators in the UK last month approved the twice-daily pill Molnupiravir, manufactured by Merck/Ridgeback, for use in elderly and at-risk patients, but its approval has stalled in the US amid safety concerns.

The Pfizer pills are taken every 12 hours. They reduced the risk of hospitalization or death by 89% within three days of symptom onset and 88% within five days.

Dolsten said that more than 200 scientists had been working to develop the pill since early 2020, and that the initial hope had been for it to be at least 60% effective. It works by inhibiting an enzyme known as a protease, which is prominent in the rapidly spreading Omicron mutation of Covid-19.

Dolsten said that Pfizer would have 180,000 courses of treatment ready if Paxlovid was authorized soon, and that the company planned to make 80m courses available worldwide in 2022.

Meanwhile, a study in South Africa has suggested that the Pfizer vaccine has a weaker efficacy against Omicron in patients who have received two doses than it does against the Delta variant.

The group said that represented a drop from 93% hospitalization protection and 80% infection prevention for Delta.

Reuters contributed to this report