Outcomes and Healthcare Resource Utilization in Patients with COVID-19 Treated with Nirmatrelvir-Ritonavir: Real-World Data Analysis.

Nirmatrelvir-ritonavir was granted emergency use authorization in Israel in January 2022 to treat high-risk patients with mild-to-moderate COVID-19. The aim of the study was to assess the association between nirmatrelvir-ritonavir treatment and COVID-19-related hospitalization and healthcare resource utilization (HCRU) in a country with a high level of vaccinations compared to patients who were offered treatment and declined. The Maccabi Healthcare Services dataset was used to identify high-risk SARS-CoV-2-positive adults from January to February 2022 who received nirmatrelvir-ritonavir within 5 days of symptom onset (treatment group) or who were offered nirmatrelvir-ritonavir treatment and declined it (reference group). COVID-19-related hospitalizations and all-cause mortality and HCRU within 30 days were compared between treatment and reference groups using inverse probability of treatment weighting. Treatment and reference groups included 3460 (median age, 68.4 years) and 1654 (70.2 years) patients, respectively. Patients with ≥1 dose of COVID-19 vaccine accounted for 89.5% (treatment group) and 72.1% (reference group) of the total. Treatment was associated with a lower risk of COVID-19-related hospitalization (adjusted OR, 0.59 [95% CI, 0.41,0.83]). Results were similar by age group (18-64/≥65 years) and among patients with/without vaccination in the prior 180 days. There were 11 (0.3%) versus 11 (0.7%) deaths in the treatment and reference groups, respectively. Treated patients had lower inpatient HCRU and greater less intensive outpatient HCRU (e.g., telemedicine and emergency room visits). Nirmatrelvir-ritonavir treatment was associated with a reduced risk of COVID-19-related hospitalization and a shift to less intensive outpatient HCRU. Comparison with a reference group of nirmatrelvir-ritonavir-eligible patients who declined treatment enabled an unbiased outcome assessment. Real-world data gathered during the Omicron BA.1 variant wave of COVID-19 in Israel support the continued use of nirmatrelvir-ritonavir for high-risk adults of all ages, regardless of previous vaccinations.