Effectiveness of nirmatrelvir/ritonavir and molnupiravir on post-COVID-19 outcomes among outpatients: a target trial emulation investigation
PhD Yuchen Wei, PhD Christopher Boyer, MSc Katherine Min Jia, MSc Guozhang Lin, MPhil Huwen Wang, MSc Conglu Li, MBBS Chi Tim Hung, MSc Xiaoting Jiang, Carrie Ho Kwan Yam, Tsz Yu Chow, PhD Yawen Wang, PhD Shi Zhao, MSc Zihao Guo, MSc Kehang Li, PhD Aimin Yang, Chris Ka Pun Mok, David Sc Hui, PhD Ka Chun Chong, Eng Kiong Yeoh
Emerging Microbes & Infections, doi:10.1080/22221751.2025.2469648
Limited studies compared the effectiveness of nirmatrelvir/ritonavir and molnupiravir against a control group on post-COVID-19 conditions. Our study examined the association of nirmatrelvir/ritonavir and molnupiravir with post-acute mortality and hospitalizations among outpatients using real-world outpatient records of COVID-19 designated clinics in Hong Kong. This is an observational study using a target trial emulation framework, involving nirmatrelvir-ritonavir versus no antiviral treatment (Trial 1) and molnupiravir versus no antiviral treatment (Trial 2). Outcomes included post-acute mortality, all-cause hospitalization, and hospitalization due to 13 selected sequelae. Relative effectiveness was assessed by comparing the cumulative incidence between two groups, reported as relative risk (RR), along with risk differences (RD) during day 0-30, 31-180, and 181-360. After screening, 140477 and 96030 patients were included in Trial 1 and 2, respectively. Compared with no treatment, nirmatrelvir/ritonavir-treated patients exhibited a significantly lower risk of post-acute mortality (31-180 days: RR, 0.71; 95% CI, 0.54-0.96; RD, 0.20%; 181-360 days: RR, 0.64; 95% CI, 0.50-0.82; RD, 0.32%) and all-cause hospitalization (31-180 days: RR, 0.82; 95% CI, 0.76-0.88; RD, 1.11%; 181-360 days: RR, 0.83; 95% CI, 0.78-0.89; RD, 1.18%). Patients receiving molnupiravir had a lower risk of 30-day mortality, but no significant beneficial effect was observed for the post-acute outcomes. In conclusion, this study demonstrated the effectiveness of nirmatrelvir/ritonavir in reducing post-COVID-19 outcomes among outpatients. While we observed the short-term effectiveness of molnupiravir in reducing mortality, no protective effect on long-term post-COVID-19 outcomes was observed.
Declarations
Ethics approval and consent to participate: This study followed the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) reporting guideline. Ethics approval was obtained from the Joint Chinese University of Hong Kong and New Territories East Cluster clinical research ethics committee, Hong Kong (Ref No. 2023.006). As this study was a retrospective analysis using secondary data without any personal information, the requirement for informed consent was waived.
Consent for publication: Not applicable.
Competing interests: We declare that we have no conflicts of interest.
Contributions: Study design and conceptualisation: YWei, CB, KMJ, GL, KCC. Data collection and pre-processing: YWei, HW, CHKY, TYC, ZG, EKY. Data analysis and interpretation: YWei, CB, KMJ, KCC. Writing -Original Draft: YWei, CB, KMJ, HW, GL, CTH, XJ, CL, SZ, CKPM, DSCH, KCC. Writing -Review and Editing: HW, CHKY, TYC, KL, AY, EKY. EKY and KCC have accessed and verified all the data. All authors critically reviewed the manuscript and gave final approval for publication. Table S4 . Illustration of censoring and weighting during the 5-days grace period.
Person (i) Time Treatment Weight not being censored from the treatment arm within grace period Weight not being censored from the no treatment arm within grace period ) 0 p0 = probability of being censored from the treatment arm in Day 0, p1 = probability of being censored from the no treatment arm in day 1, etc...
References
Arbel, Sagy, Hoshen, Nirmatrelvir Use and Severe Covid -19 Outcomes during the Omicron Surge, N Engl J Med
Bajema, Berry, Streja, Rajeevan, Li et al., Effectiveness of COVID-19 Treatment With Nirmatrelvir-Ritonavir or Molnupiravir Among U.S. Veterans: Target Trial Emulation Studies With One-Month and Six-Month Outcomes, Ann Intern Med
Durstenfeld, Peluso, Lin, Association of nirmatrelvir for acute SARS-CoV-2 infection with subsequent Long COVID symptoms in an observational cohort study, J Med Virol
Fung, Baye, Baik, Mcdonald, Nirmatrelvir and Molnupiravir and Post-COVID-19 Condition in Older Patients, JAMA Intern Med
Guo, Zhao, Mok, So, Yam et al., Comparing the incubation period, serial interval, and infectiousness profile between SARS-CoV-2 Omicron and Delta variants, J Med Virol
Hammond, Fountaine, Yunis, Fleishaker, Almas et al., Nirmatrelvir for vaccinated or unvaccinated adult outpatients with Covid-19, N Engl J Med
Hammond, Leister-Tebbe, Gardner, Abreu, Wisemandle et al., Oral Nirmatrelvir for High-Risk, Nonhospitalized Adults with Covid-19, N Engl Med
Hsu, Shiau, Tsai, Wu, Liu et al., The effect of molnupiravir on post-acute outcome of COVID-19 survivors, J Infect
Ioannou, Berry, Rajeevan, Effectiveness of Nirmatrelvir-Ritonavir Against the Development of Post-COVID-19 Conditions Among U.S. Veterans : A Target Trial Emulation, Ann Intern Med
Kostev, Smith, Koyanagi, Konrad, Jacob, Post-COVID-19 conditions in children and adolescents diagnosed with COVID-19, Pediatr Res
Lam, Wong, Zhang, Long-term post-acute sequelae of COVID-19 infection: a retrospective, multi-database cohort study in Hong Kong and the UK, EClinicalMedicine
Lin, Wei, Wang, Boyer, Jia et al., Association of nirmatrelvir-ritonavir with post-acute sequelae and mortality among patients who are immunocompromised with COVID-19 in Hong Kong: a retrospective cohort study, Lancet Rheumatol
Sebők, Gyires, Long COVID and possible preventive options, Inflammopharmacology
Vangeel, Chiu, Jonghe, Maes, Slechten et al., Remdesivir, Molnupiravir and Nirmatrelvir remain active against SARS-CoV-2 Omicron and other variants of concern, Antiviral Res
Wang, Wei, Hung, Lin, Jiang et al., Association of nirmatrelvir-ritonavir with post-acute sequelae and mortality in patients admitted to hospital with COVID-19: a retrospective cohort study, Lancet Infect Dis
Wang, Wei, Lin, Boyer, Jia et al., COVID-19 vaccination modified the effect of nirmatrelvir-ritonavir on post-acute mortality and rehospitalization: a retrospective cohort study, Emerg Microbes Infect
Wei, Jia, Zhao, Hung, Mok et al., Estimation of Vaccine Effectiveness of CoronaVac and BNT162b2 Against Severe Outcomes Over Time Among Patients With SARS-CoV-2 Omicron, JAMA Netw Open
Wong, Au, Lau, Lau, Cowling et al., Real-world effectiveness of early molnupiravir or nirmatrelvir-ritonavir in hospitalised patients with COVID-19 without supplemental oxygen requirement on admission during Hong Kong's omicron BA.2 wave: a retrospective cohort study, Lancet Infect Dis
Xie, Choi, Al-Aly, Association of Treatment With Nirmatrelvir and the Risk of Post-COVID-19 Condition, JAMA Intern Med
Xie, Choi, Al-Aly, Molnupiravir and risk of post-acute sequelae of covid-19: cohort study, BMJ
Zuo, Yu, Campbell, Yamamoto, Yuan, The implementation of target trial emulation for causal inference: a scoping review, J Clin Epidemiol
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