Nirmatrelvir/ritonavir prescription and the risk of hospitalization and death in COVID-19 outpatients

Abstract

Objective

The nirmatrelvir/ritonavir is an oral combination of antiviral drugs used to treat the COVID-19. In this study we evaluated the risk of hospitalization and death, comparing COVID-19 patients who received and did not receive ambulatory nirmatrelvir/ritonavir prescription.

Material and methods

A two-group comparative study was carried out using data from the Mexican Institute of Social Security medical information systems. We analyzed of 83,348 ambulatory patients aged 18 years old and over and with laboratory confirmed SARS-CoV-2 infection during the period from September 12th, 2022, to September 30th, 2023. Of them, 27,437 received nirmatrelvir/ritonavir prescription (32.9%) and 55,911 did not (67.1%). We compared the 60-day COVID-19 related hospitalization and all-cause death risk among groups using a multivariate Poisson regression model.

Results

The 60-day COVID-19 related hospitalization and all-cause death combined incidence was 0.13% in the patients who received nirmatrelvir/ritonavir and 0.26% among the cases who did not receive the prescription. In the multivariate model, after adjusting for age, sex, and previous medical conditions such as chronic kidney disease, chronic obstructive pulmonary disease and cardiovascular disease, the nirmatrelvir/ritonavir prescription was associated with a decrease in 60-day hospitalization and death, with an adjusted risk ratio of 0.52 (95% confidence interval from 0.36 to 0.75).

Conclusions

Our data supports that nirmatrelvir/ritonavir prescription is associated with a risk reduction of 60-day COVID-19 related hospitalization and death, in outpatients with COVID-19.