Monoclonal Antibody Treatment of Breakthrough COVID-19 in Fully Vaccinated Individuals with High-Risk Comorbidities

Abstract

Breakthrough COVID-19 may occur in fully vaccinated persons. In this cohort of 1395 persons (mean age, 54.3 years; 60% female; median body mass index, 30.7) who developed breakthrough COVID-19, there were 107 (7.7%) who required hospitalization by day 28. Hospitalization was significantly associated with the number of medical comorbidities. Anti-spike monoclonal antibody treatment was significantly associated with a lower risk of hospitalization (Odds Ratio: 0.227; 95% confidence interval, 0.128 - 0.403; p<0.001). The number needed to treat (NNT) to prevent one hospitalization was 225 among the lowest-risk patient group compared to NNT of 4 among those with highest numbers of medical comorbidity.

Doubtful clinical benefit of casirivimab-imdevimab treatment for disease severity outcome of high-risk patients with SARS-CoV-2 delta variant infection

“…REGEN-COV, a combination of 2 neutralizing monoclonal antibodies, Casirivimab and Imdevimab has been shown to reduce the viral load, shorten the symptoms duration, reduce the need for hospitalization and the risk of death in high-risk non-hospitalized patients [2] . Delta variant became a variant of concern by WHO on May 11, 2021 [3] , but there are only sparse data [4] on Casirivimab / Imdevimab therapy clinical benefit against the Delta variant and specifically with respect to its effect among vaccinated patients [4] . Bierle et al [4] .…”

“…Delta variant became a variant of concern by WHO on May 11, 2021 [3] , but there are only sparse data [4] on Casirivimab / Imdevimab therapy clinical benefit against the Delta variant and specifically with respect to its effect among vaccinated patients [4] . Bierle et al [4] . found monoclonal antibody treatment to be associated with reduced hospitalization in vaccinated high-risk persons with mild-to moderate COVID-19.…”

Doubtful Clinical Benefit of Casirivimab-Imdevimab Treatment for Disease Severity Outcome of High-Risk Patients with SARS-CoV-2 Delta Variant Infection

“…Delta variant became a variant of concern by WHO on May 11, 2021 (10). While Casirivimab/Imdevimab therapy was found to retain neutralization potency against circulating SARS-CoV-2 variants of concern, including delta (B.1.617.2) in vitro and in vivo (6,11,12), there are only sparse data (13) on its clinical benefit against the Delta variant.…”

“…A recent study on patients infected with non-delta SARS-CoV-2 found that Casirivimab/Imdevimab reduced the 28-day mortality among hospitalized patients who were seronegative at baseline (14). Most of the other relevant studies had been performed prior to the vaccination era, and little has been published with respect to its effect among vaccinated patients (13). An exception is Bierle et al (13) who found monoclonal antibody treatment to be associated with reduced hospitalization in vaccinated high-risk persons with mild-to moderate COVID-19.…”

“…Most of the other relevant studies had been performed prior to the vaccination era, and little has been published with respect to its effect among vaccinated patients (13). An exception is Bierle et al (13) who found monoclonal antibody treatment to be associated with reduced hospitalization in vaccinated high-risk persons with mild-to moderate COVID-19. However, and their study was initiated prior to May 2021, it was not focused on the Delta variant.…”