Table 2. Observational studies for molnupiravir.

Authors	Participants	Design	Place	Period	Dominant strain	No. of patients	Vaccination status	Primary outcome	Reference
Suzuki, Yasuhito et al.	mild-moderate COVID-19 patients with risk factors for progression to severe diseases	retrospective cohort study	multicenter in Fukushima, Japan	January–April, 2022	omicron	molnupiravir: 230 control: 690 (after propensity score matching)	vaccinated at least twice molnupiravir: 81.7% control: 82.2%	any deterioration aOR 0.448, 95% CI 0.206–0.973 all-cause death no significant difference (effect size not shown)	26
Wong, Carlos K H et al.	hospitalized patients not requiring oxygen therapy on admission	retrospective cohort study	database of Hospital Authority, the Department of Health, and the Hong Kong Death Registry	February–April, 2022	omicron	molnupiravir: 1,856 control: 1,856 (after propensity score matching)	vaccinated at least twice molnupiravirr: 6.2% control: 9.0%	all-cause mortality HR 0.48, 95% CI 0.40–0.59	23
Wong, Carlos K H et al.	ambulatory mild to moderate Covid-19 patients with risk of progressing to severe disease	retrospective cohort study	public inpatient and outpatient services in Hong Kong	February–June, 2022	omicron	molnupiravir: 4983 control: 49234	vaccinated at least twice molnupiravir: 16.1% control: 33.2%	all-cause mortality HR 0.76, 95% CI 0.61–0.95 hospitalisation HR 0.98, 95% CI 0.89–1.06 In-hospital disease progression HR 0.57, 95% CI 0.43–0.79	24
Wai, Abraham Ka-Chung et al.	mild to moderate COVID-19 patients risk factors for progression to severe diseases	retrospective cohort study	database of Hospital Authority, Hong Kong	February–March, 2022	omicron	molnupiravir: 20,224 control: 20,057	data not available 82.6% of population vaccinated twice	28-day all-cause mortality HR 0.31, 95% CI 0.24–0.40	25

HR = hazard ratio, CI = confidence interval, aOR = adjusted odds ratio