Nirmatrelvir/ritonavir and remdesivir against symptomatic treatment in high-risk COVID-19 outpatients to prevent hospitalization or death during the Omicron era: a propensity score-matched study

Ther Adv Infect Dis. 2024 Mar 26:11:20499361241236582. doi: 10.1177/20499361241236582. eCollection 2024 Jan-Dec.

Abstract

Background: Even though worldwide death rates from coronavirus disease 2019 (COVID-19) have decreased, the threat of disease progression and death for high-risk groups continues. Few direct comparisons between the available severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antivirals have been made.

Objective: We aimed to compare two SARS-CoV-2 antivirals (nirmatrelvir/ritonavir and remdesivir) against all-cause hospitalization or death.

Design: This is a propensity score-matched cohort study.

Methods: We included all high-risk outpatients with COVID-19 in a tertiary referral center in Mexico City from 1 January 2022 to 31 July 2023. The primary outcome was all-cause hospitalization or death 28 days after symptom onset. The secondary outcome was COVID-19-associated hospitalization or death 28 days after symptom onset. Logistic regression analysis for characteristics associated with the primary outcome and a multi-group comparison with Kaplan-Meier survival estimates were performed.

Results: Of 1566 patients analyzed, 783 did not receive antiviral treatment, 451 received remdesivir, and 332 received nirmatrelvir/ritonavir. The median age was 60 years (interquartile range: 46-72), 62.5% were female and 97.8% had at least one comorbidity. The use of nirmatrelvir/ritonavir was associated with an absolute risk reduction of 8.8% and a relative risk reduction of 90% for all-cause hospitalization or death. The use of remdesivir was associated with an absolute risk reduction of 6.4% and a relative risk reduction of 66% for all-cause hospitalization or death. In multivariable analysis, both antivirals reduced the odds of 28-day all-cause hospitalization or death [nirmatrelvir/ritonavir odds ratio (OR) 0.08 - 95% confidence interval (CI): 0.03-0.19, remdesivir OR 0.29 - 95% CI: 0.18-0.45].

Conclusion: In high-risk COVID-19 outpatients, early antiviral treatment with nirmatrelvir/ritonavir or remdesivir was associated with lower 28-day all-cause hospitalization or death.

Keywords: COVID-19; early treatment; nirmatrelvir/ritonavir; remdesivir.

Plain language summary

Nirmatrelvir/ritonavir and remdesivir against symptomatic treatment in high-risk COVID-19 outpatients In this study, we included high-risk non-hospitalized patients with confirmed mild COVID-19. We compared those who received antiviral treatment (nirmatrelvir/ritonavir or remdesivir) against those who only received symptomatic treatment. The aim was to detect differences in hospitalization or death 28 days after symptom onset. We analyzed 1566 patients: 783 did not receive antiviral treatment, 451 received remdesivir, and 332 received nirmatrelvir/ritonavir. Most patients were female and over 60 years old. The most common comorbidities were chronic hypertension (44%), diabetes mellitus (26%), and autoimmune diseases (25%); systemic immunosuppression was registered in 35% of patients. Hospitalization or death 28 days after symptom onset occurred in 168 patients (136 in the symptomatic treatment group, 27 in the remdesivir group, and 5 in the nirmatrelvir/ritonavir group). Considering multiple variables like age, sex, comorbidities, and previous vaccination, both antivirals significantly reduced the odds of hospitalization or death (nirmatrelvir/ritonavir odds ratio 0.08, 95% confidence interval 0.03-0.19; remdesivir odds ratio 0.29, 95% confidence interval 0.18-0.45).