Pfizer Inc. shared top-line results from the phase 2/3 EPIC-PEP (Evaluation of Protease Inhibition for Covid-19 in Post-Exposure Prophylaxis) study evaluating Paxlovid (nirmatrelvir [PF-07321332] tablets and ritonavir tablets) for post-exposure prophylactic use. In this trial, compared to placebo, Pfizer observed risk reductions of 32% and 37% in adults who received Paxlovid for five and ten days, respectively, to prevent infection. These results, however, were not statistically significant and, as such, the primary endpoint of reducing the risk of confirmed and symptomatic Covid-19 infection in adults who had been exposed to the virus through a household contact was not met.
Available safety data for Paxlovid has been generally consistent in more than 3,500 Paxlovid-treated participants across the EPIC-HR, EPIC-SR and EPIC-PEP studies, as well as in reported post-market safety experience. In EPIC-PEP, this safety profile remained generally consistent when Paxlovid was used for either five or ten days. Analyses of all secondary endpoints and sub-groups are ongoing, and results will be included in the publication or presentation of the final study results.
