Nirmatrelvir-Ritonavir (Paxlovid) for the Treatment of COVID-19

Several drug treatments for COVID-19 caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are approved for use in Canada. This systematic review evaluated the efficacy, effectiveness, and safety of nirmatrelvir-ritonavir in adults with SARS-CoV-2 infection who are considered high risk but are not hospitalized. We also characterized which patients are most likely to benefit from treatment with nirmatrelvir-ritonavir.

Nirmatrelvir-ritonavir may be effective in reducing emergency department visits, hospitalizations, and death. It appears to be comparably effective as other antivirals (i.e., molnupiravir and remdesivir), but nirmatrelvir-ritonavir may have a higher incidence of mild to moderate adverse events. Nirmatrelvir-ritonavir also appears to be more effective in people who are partially vaccinated or not vaccinated compared with those who are fully vaccinated. The studies demonstrating these findings lack a diverse lens, which may limit their generalizability to the population in Canada.