Primovir is a co-packaged medication used as a treatment for COVID 19. It contains the antiviral medications nirmatrelvir and ritonavir and was developed by Pfizer.
Both are protease inhibitors: nirmatrelvir inhibits SARS-CoV-2 main protease, while ritonavir inhibits HIV-1 protease, and is additionally a strong CYP3A inhibitor.
In the United States, nirmatrelvir/ritonavir is indicated for the treatment of mild-to-moderate COVID 19 in adults who are at high risk for progression to severe COVID 19, including hospitalization or death.
It is not authorized or suggested for the pre-exposure or post-exposure prevention of COVID 19.
In the European Union, the co-packaged medication is indicated for the treatment of COVID 19 in adults who do not require supplemental oxygen and who are at increased risk for progressing to severe COVID 19.
If administered within five days of symptom onset in confirmed COVID-19 infections, the efficacy of the co-packaged medication against hospitalization or death in unvaccinated high-risk adults is about 88% (95%, 75–94%).
