Early initiation of molnupiravir or nirmatrelvir/ritonavir in community-dwelling adults with COVID-19 was associated with reduced risks of mortality and in-hospital disease progression during a wave of SARS-CoV-2 omicron subvariant BA.2.2 infections in Hong Kong. In addition, the observational study shows an association between nirmatrelvir plus ritonavir use and reduced risk of hospitalization.
The researchers used hospital data to conduct a retrospective cohort primary analysis and a case-control sensitivity analysis. Among 1.1 million nonhospitalized people diagnosed with COVID-19 from Feb. 26 to June 26, 2022, 5,383 on molnupiravir and 6,464 on nirmatrelvir plus ritonavir were followed up for a median of about 100 days. The risk of death was decreased by 24% with molnupiravir use and 66% with nirmatrelvir/ritonavir. “We consistently found reduced risks of mortality and hospitalisation associated with early oral antiviral use among older patients,” the authors write. “The findings from the case-control analysis broadly supported those from the primary analysis.”
The group concludes: “Guidelines prioritise nirmatrelvir plus ritonavir use over molnupiravir in community-dwelling patients with COVID-19 who are at high risk of hospitalisation or progression to severe disease, should nirmatrelvir plus ritonavir be accessible and clinically appropriate. Although our results suggest similar trends to those of the MOVe-OUT and EPIC-HR trials, discrepancies in the respective effect sizes could possibly be attributed, at least partly, to differences in the risk profile of patients (as indicated by the older age of our patients vs overweight or obesity being the major risk factor in patients in the two clinical trials, and <20% of patients being aged >60 years or >65 years), or the circulating variant of concern (omicron in this study vs delta in previous trials).”