Real-world evidence of sotrovimab effectiveness for preventing severe outcomes in patients with COVID-19: A quality improvement propensity-matched retrospective cohort study of a pan-provincial program in Alberta, Canada.

• Post-marketing surveillance of sotrovimab in Canada is limited. • Sotrovimab was not associated with improved outcomes. • Study results were consistent across different analytic methodologies. • Study findings need to be confirmed in other Canadian provinces. Post-marketing surveillance of sotrovimab's effect during implementation in the Canadian population is limited. The study used a propensity score–matched retrospective cohort design. Follow-up began between the periods of December 15, 2021 and April 30 2022. The study assessed any severe outcome defined as all-cause hospital admission or mortality within 30 days of a confirmed COVID-19–positive test. Covariate-adjusted odds ratios between sotrovimab treatment and the severe outcome was conducted using logistic regression. There were 22,289 individuals meeting the treatment criteria for sotrovimab. There were 1603 treated and 6299 untreated individuals included in the analysis. The outcome occurrence in the study was 5.49% (treated) and 4.21% (untreated), with a median time from diagnosis to treatment of 1.00 days (interquartile range 2.00 days). In the propensity-matched cohort, sotrovimab was not associated with lower odds of a severe outcome (odds ratio 1.20, 95% confidence interval 0.91-1.58), adjusting for confounding variables. After adjusting for confounding variables, sotrovimab treatment was not associated with lower odds of a severe outcome within 30-days of COVID-19–positive date. [ABSTRACT FROM AUTHOR]