Real-world effectiveness of sotrovimab for the treatment of SARS-CoV-2 infection during Omicron BA.2 subvariant predominance: a systematic literature review

Purpose Emerging SARS-CoV-2 variants have impacted the in vitro activity of sotrovimab, with variable fold changes in neutralization potency for the Omicron BA.2 sublineage and onward. The correlation between reduced in vitro activity and clinical efficacy outcomes is unknown. A systematic literature review (SLR) evaluated the effectiveness of sotrovimab on severe clinical outcomes during Omicron BA.2 predominance. Methods Electronic databases were searched for peer-reviewed journals, preprint articles, and conference abstracts published from January 1–November 3, 2022. Results Five studies were included, which displayed heterogeneity in study design and population. Two UK studies had large samples of patients during BA.2 predominance: one demonstrated clinical effectiveness vs molnupiravir during BA.1 (adjusted hazard ratio [aHR] 0.54, 95% CI 0.33–0.88; p = 0.014) and BA.2 (aHR 0.44, 95% CI 0.27–0.71; p = 0.001); the other reported no difference in the clinical outcomes of sotrovimab-treated patients when directly comparing sequencing-confirmed BA.1 and BA.2 cases (HR 1.17, 95% CI 0.74–1.86). One US study showed a lower risk of 30-day all-cause hospitalization/mortality for sotrovimab compared with no treatment during the BA.2 surge in March (adjusted relative risk [aRR] 0.41, 95% CI 0.27–0.62) and April 2022 (aRR 0.54, 95% CI 0.08–3.54). Two studies from Italy and Qatar reported low progression rates but were either single-arm descriptive or not sufficiently powered to draw conclusions on the effectiveness of sotrovimab. Conclusion This SLR showed that the effectiveness of sotrovimab was maintained against Omicron BA.2 in both ecological and sequencing-confirmed studies, by demonstrating low/comparable clinical outcomes between BA.1 and BA.2 periods or comparing against an active/untreated comparator.