FDA Requests More Trial Data Related to Pfizer’s Paxlovid

The FDA has asked Pfizer for additional trial data to address concerns about the return of COVID-19 symptoms within days of an initial treatment with the company’s combination antiviral drug Paxlovid (nirmatrelvir, ritonavir).

The agency wants the company to conduct a placebo-controlled trial to evaluate a subsequent treatment course of Paxlovid and expects to see topline results by Sept. 30, 2023.

Pfizer is also expected to submit data by the same deadline from a controlled trial to evaluate different durations of Paxlovid treatment in immunocompromised patients with mild-to-moderate COVID-19.

Paxlovid is currently FDA-authorized for treatment of mild-to-moderate COVID-19 in adults and pediatric patients 12 years of age and older weighing at least 40 kg.