Nirmatrelvir and ritonavir combination against COVID‐19 caused by omicron BA.2.2 in the elderly: A single‐center large observational study

Abstract

Abstract Background Since coronavirus 2019 (COVID‐19) swept the world, a variety of novel therapeutic and prevention strategies have been developed, among which nirmatrelvir–ritonavir is highly recommended. We intended to assess the effectiveness and safety of nirmatrelvir–ritonavir in the elderly mild‐to‐moderate COVID‐19 population caused by the omicron BA.2.2 variant in real‐world settings. Methods An observational study was conducted retrospectively to review the outcomes of mild‐to‐moderate COVID‐19 patients admitted between April 26 and June 30, 2022. Patients' baseline characteristics were collected and assessed. Participants in the intervention group were administered nirmatrelvir–ritonavir in addition to standard care, whereas those in the control group only received standard care. The primary outcome was the duration between the initial positive reverse‐transcription polymerase chain reaction (RT‐PCR) test and the subsequent conversion to a negative result. Results The analysis included 324 patients who were administered nirmatrelvir–ritonavir and an equal number of control patients. The patient characteristics in both groups were evenly matched. The average duration from the initial positive RT‐PCR to negative conversion was similar in both groups (16.2 ± 5.0 vs. 16.1 ± 6.3 days, p = .83). Control patients exhibited slower conversion in comparison to patients who received nirmatrelvir–ritonavir treatment within 10 days of symptom onset. Conclusions These findings suggest that administering nirmatrelvir–ritonavir within 10 days of symptom onset could potentially reduce the time it takes for SARS‐CoV‐2‐infected patients to negative RT‐PCR results, thereby expanding the current usage guidelines for nirmatrelvir–ritonavir.

Keywords

• COVID‐19
• nirmatrelvir–ritonavir
• observational study