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REGEN-COV as the First Line of Defense-A Single-Centre Experience
Milica Popović1,2, Vladimir Đurović1,2, Bojana Ljubičić1,3
1Faculty of Medicine, University of Novi Sad, 21000 Novi Sad, Serbia.
Background:
Casirivimab-imdevimab (REGEN-COV) is a neutralizing antibody cocktail that has been shown to prevent the progression of COVID-19 and serious adverse outcomes in patients with COVID-19 disease. During the period preceding the emergence of the Omicron variant, REGEN-COV demonstrated clinical activity against several circulating SARS-CoV-2 variants. The delta variant was dominant worldwide during much of the study period.
Aim:
This retrospective observational study aimed to show the single centre's results in treating patients with REGEN-COV.
Methods:
This study included adult patients who received REGEN-COV at our COVID-19 centre from 01 June 2021 to 31 January 2022 (REGEN-COV group) and a comparison group that included patients who did not meet the eligibility criteria for REGEN-COV (non-REGEN-COV group). The primary end-point was the need for hospitalization. The secondary end-point was all-cause mortality. Intensive care unit admission was also evaluated.
Results:
This study included 206 patients, of whom 69 received REGEN-COV, and 137 comprised the non-REGEN-COV group. During follow-up, 128 patients (62%) required hospitalization, including 11 (15.9%) in the REGEN-COV group and 117 (85.4%) in the non-REGEN-COV group (p < 0.001). Mortality occurred in 2 patients (2.9%) treated with REGEN-COV compared with 30 patients (21.9%) in the non-REGEN-COV group. In the propensity score-matched analysis, the average marginal absolute risk difference for mortality between the groups was -4.0% (95% CI -9.8 to 1.8), p = 0.178; however, Kaplan-Meier survival analysis demonstrated a significant difference in survival between groups (log-rank p < 0.001).
Conclusions:
Our study showed that in high-risk patients, with specific variants of SARS-CoV-2, the use of REGEN-COV was associated with a lower risk of hospitalization, and it was associated with better disease outcomes. One of the limitations of this study was the variant-specific effectiveness of REGEN-COV, which may limit generalizability.
Insights
Casirivimab-imdevimab (REGEN-COV) reduced hospitalization and improved outcomes in high-risk COVID-19 patients during the Delta variant surge. This study highlights REGEN-COV
Area of Science:
- Infectious Diseases
- Virology
- Immunology
Background:
- Casirivimab-imdevimab (REGEN-COV) is a neutralizing antibody cocktail effective against SARS-CoV-2 variants.
- Previous studies demonstrated REGEN-COV's efficacy in preventing COVID-19 progression and severe outcomes.
- The Delta variant was globally dominant during the study period.
Purpose of the Study:
- To evaluate the real-world effectiveness of REGEN-COV in a single center.
- To compare hospitalization and mortality rates between REGEN-COV treated and untreated patients.
Main Methods:
- Retrospective observational study of adult patients from June 2021 to January 2022.
- REGEN-COV group (n=69) vs. non-REGEN-COV group (n=137).
- Primary endpoint: hospitalization; Secondary endpoints: all-cause mortality and ICU admission.
Main Results:
- Hospitalization occurred in 15.9% of the REGEN-COV group versus 85.4% in the non-REGEN-COV group (p < 0.001).
- Mortality was 2.9% in the REGEN-COV group compared to 21.9% in the non-REGEN-COV group.
- Kaplan-Meier survival analysis showed a significant difference in survival between groups (log-rank p < 0.001).
Conclusions:
- REGEN-COV use was associated with reduced hospitalization and better outcomes in high-risk COVID-19 patients with specific SARS-CoV-2 variants.
- Variant-specific effectiveness may limit the generalizability of findings.
- Further research is needed to confirm these findings across diverse populations and variants.
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