Change in Effectiveness of Sotrovimab for Preventing Hospitalization and Mortality for At-risk COVID-19 Outpatients During an Omicron BA.1 and BA.1.1-Predominant Phase

Abstract

Objectives

Sotrovimab effectively prevented progression to severe disease and mortality following infection with pre-Omicron SARS-CoV-2 variants. We sought to determine whether sotrovimab is similarly effective against SARS-CoV-2 Omicron variant infection.

Methods

Observational cohort study of non-hospitalized adult patients with SARS-CoV-2 infection from December 26, 2021 to March 10, 2022, using electronic health records from a statewide health system. We propensity matching patients not receiving authorized treatment for each patient treated with sotrovimab . The primary outcome was 28-day hospitalization; secondary outcomes included mortality. We also propensity matched sotrovimab-treated patients from the Omicron and Delta phases. Logistic regression was used to determine sotrovimab effectiveness during Omicron and between variant phases.

Results

Of 30,247 SARS-CoV-2 Omicron variant infected outpatients, we matched 1,542 receiving sotrovimab to 3,663 not receiving treatment. Sotrovimab treatment was not associated with reduced odds of 28-day hospitalization (2.5% versus 3.2%; adjusted OR 0.82, 95% CI 0.55, 1.19) or mortality (0.1% versus 0.2%; adjusted OR 0.62, 95% CI 0.07, 2.78). Between phases, the observed treatment odds ratio was higher during Omicron than during Delta (OR 0.85 vs. 0.39, respectively; interaction p=0.053).

Conclusions

Real-world evidence demonstrated sotrovimab was not associated with reduced 28-day hospitalization or mortality among COVID-19 outpatients during the Omicron BA.1 phase.