U.S. Food and Drug Administration staff said on Tuesday Pfizer’s results from clinical trials of its Covid antiviral pill Paxlovid support the use of the drug in adults at high risk of progression to serious illness.
FDA staff concluded by documents d’information before a meeting on Thursdaywhen external advisers from the agency’s Antimicrobial Drug Advisory Committee discuss whether to recommend full approval of Paxlovid for the treatment of mild to moderate Covid in high-risk adults.
At the meeting, advisors will review the evidence related to Paxlovid’s effectiveness and vote on whether the benefits outweigh the risks of using the drug. The FDA generally follows the advice of its advisory committees, but is not required to do so.
The FDA cleared Paxlovid for emergency use in December 2021. Pfizer submitted an application for full drug approval in June 2022, and the FDA extended the exam period of the application in December 2022. The agency is expected to complete its review in May.
The meeting comes as companies like Pfizer and Modern prepare for a drop in sales of Covid vaccines and treatments that led to record revenues earlier in the pandemic. Paxlovid’s sales jumped to $18.9 billion in 2022, its first year of availability, but the company said it expects those revenues to drop 58% to $8 billion this year. .
More than 12 million courses of Paxlovid have been delivered to pharmacies across the United States, according to federal data. About 8 million Americans have taken the drug, with about 1.3 million doses available at national scale.
FDA staff reviewed Pfizer’s mid to late phase clinical trials of Paxlovid. In a trial called EPIC-HR, Paxlovid showed an 86% reduction in the risk of hospitalization or death in high-risk adults who had not received a Covid vaccine. No deaths were observed during the trial.
Paxlovid has been plagued by reports of ‘rebounding’ Covid infections, where patients see their Covid symptoms or a positive test return after completing a five-day course of the oral drug. Last year, President Joe Biden and his former chief medical adviser, Dr. Anthony Fauci, experienced cases of rebound after taking Paxlovid.
But FDA staff highlighted trial data that showed overall rebound rates ranged from 10% to 16%, “with no evidence of a higher rate of symptom rebound or moderate symptom rebound.” in patients who received Paxlovid compared to a placebo. It was also regardless of the patients’ risk of serious illness, or whether the omicron variant of Covid or an earlier strain was dominant, the staff said.
