Paxlovid reduces the 28-day mortality of patients with COVID-19: a retrospective cohort study.

Purpose: In this study, we aim to explore the efficacy of paxlovid on reducing mortality of COVID-19 patients in clinical setting, especially whether paxlovid modifies the risk of death in these severe and critical patients.

Methods: Our retrospective cohort study was conducted on the medical records of patients, consecutively admitted for COVID-19 to five hospitals in Chongqing, China from Dec 8, 2022 to Jan 20, 2023. Based on whether patients received paxlovid during their hospitalization, patients were grouped as paxlovid group and non-paxlovid group. We used 1:1 ratio propensity score matching (PSM) in our study to adjust for confounding factors and differences between groups. Statistical analysis were performed by SPSS 23.0. The differences in 28-day mortality between these two groups and its influencing factors were the main results we focused on.

Results: There were 1018 patients included in our study cohort. With 1:1 ratio PSM, each of the paxlovid group and non-paxlovid group included 237 patients. The results showed that patients using paxlovid have a lower 28-day mortality in overall population either before PSM (OR 0.594, 95% CI 0.385-0.917, p = 0.019) or after PSM (OR 0.458, 95% CI 0.272-0.774, p = 0.003) with multivariable adjusted logistic regression models. Meanwhile, in severe subgroup, it showed similar findings.With paxlovid treatment, it showed a significantly lower 28-day mortality in severe subgroup both before PSM (28% vs.41%, p = 0.008) and after PSM (19% vs.32%, p = 0.007).

Conclusion: Paxlovid can significantly reduce the risk of 28-day mortality in overall population and severe subgroup patients.This study distinguished the severe subgroup patients with COVID-19 who benefit more from paxlovid treatment.