The U.S. Food and Drug Administration indirectly refuted Pfizer's recommendation that it's all right for COVID-19 patients to take another round of Paxlovid if they experience a rebound after completing the first course.
The regulator's reaction came after Pfizer chief executive officer Albert Bourla said in an interview that physicians may give a second five-day course of Paxlovid if patients see a spike in their SARS-CoV-2 viral load. Bourla told Bloomberg: "You give a second course, like you do with antibiotics, and that's it. Paxlovid does what it has to do: it reduces the viral load, then your body is supposed to do the job."
According to Dr. John Farley, director of the FDA's Office of Infectious Diseases, there is no data to date supporting the claim.
The FDA is looking into how often and why patients experience recurrent COVID-19 symptoms after discovering that 1% to 2% of patients had at least one positive polymerase chain reaction (PCR) test after taking the five-day course of Paxlovid or saw a spike in their viral load as per PCR. It remains unclear whether the rebound is linked to the treatment as of this writing because researchers also saw the same reaction in participants who received a placebo.
"We are continuing to review data from clinical trials and will provide additional information as it becomes available. However, there is no evidence of benefit at this time for a longer course of treatment (e.g., 10 days rather than the 5 days recommended in the Provider Fact Sheet for Paxlovid) or repeating a treatment course of Paxlovid in patients with recurrent COVID-19 symptoms following completion of a treatment course," Dr. Farley said in a CDER Conversation posted on the FDA website.
The FDA gave Paxlovid emergency use authorization after Pfizer's clinical trial demonstrated the drug's ability to reduce the risk of hospitalization or death by 88% in non-hospitalized patients at high risk of progression to severe disease.
The National Institute of Allergy & Infectious Diseases is also planning trials that would bring clarity to the relapse cases, adding that it is "urgent" and a "priority."
Until their ongoing evaluations provide definitive answers, the FDA recommends that health care providers stick to the prescribing information on Paxlovid's label, which clearly states that it should not be taken for more than five days.
"In summary, Paxlovid reduces the risk of hospitalization and death for patients with mild-to-moderate COVID-19 at high risk of disease progression. Health care providers should consider treatment with Paxlovid or other approved or authorized therapeutics in accordance with the approved labeling or authorized Health Care Provider Fact Sheets," Dr. Farley added.
