WASHINGTON — Pfizer’s COVID-19 pill, Paxlovid, won another vote of confidence from US health advisers on Thursday, paving the way for full regulatory approval by the Food and Drug Administration.
The drug has been used by millions of Americans since it was granted emergency use authorization by the FDA in late 2021. The agency has the final say on full approval of the drug from Pfizer and is expected to make a decision in May.
A panel of outside experts voted 16-1 that Paxlovid remains a safe and effective treatment for high-risk adults with COVID-19 who are more likely to face hospitalization and death from the virus.
“We still have many groups that will benefit from Paxlovid, including the unvaccinated, the undervaccinated, the elderly, and the immunocompromised,” said Dr. Richard Murphy of the Department of Veterans Affairs.
The FDA said that using Paxlovid in high-risk patients could prevent 1,500 COVID-19 deaths and 13,000 hospitalizations per week.
A positive vote from the panel was widely expected given that Paxlovid has been the gold standard treatment against COVID-19, especially since a whole group of antibody drugs have been sidelined as the virus mutated.
The US continues to report about 4,000 deaths and 35,000 hospitalizations a week, the FDA noted.
Read more: Why not everyone should take Paxlovid
The agency asked its panel of independent medical experts to address several lingering questions related to Paxlovid, including which people currently benefit from the treatment and whether the drug plays a role in rebound cases of COVID-19.
The panel agreed with the evaluations by both the FDA and Pfizer that found no clear link between Paxlovid use and recurring symptoms, but said more information is needed from studies and data from medical records. High-profile cases drew attention to the issue last year, including President Joe Biden and First Lady Jill Biden.
Between 10% and 16% of patients in various Pfizer studies had symptoms again, regardless of whether they received Paxlovid or a dummy pill. Such cases “likely reflect the natural progression of COVID-19,” the FDA concluded.
The federal government purchased more than 20 million doses of Paxlovid and encouraged healthcare professionals to aggressively prescribe it to help prevent severe COVID-19. But that raised concerns about overprescribing and questions about whether some patients are receiving the drug unnecessarily.
Pfizer originally studied Paxlovid in the highest-risk COVID-19 patients: unvaccinated adults with other health problems and no evidence of prior coronavirus infection. But that doesn’t reflect the current US population, where an estimated 95% of people are protected with at least one dose of vaccine, a previous infection, or both.
The FDA reviewed data from Pfizer showing that Paxlovid did not make a significant difference in healthy adults, whether or not they were previously vaccinated.
But when the FDA looked at data from high-risk adults, regardless of their vaccination or infection history, Paxlovid still showed significant benefit, reducing the chance of hospitalization or death by 60-85%, depending on individual circumstances. Patients in that group included older people and people with serious health problems, such as diabetes, obesity, lung disease and immune system disorders.
With so many different factors, the panelists said prescribing Paxlovid will remain a case-by-case decision.
Dr. Sankar Swaminathan of the University of Utah and other panelists stressed the importance of monitoring potentially dangerous drug interactions between Paxlovid and other commonly used medications.
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