Impact of a subcutaneous casirivimab and imdevimab clinic in outpatients with symptomatic COVID-19: A single-center, propensity-matched cohort study

Abstract

Disclaimer In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. Purpose To evaluate the success of a clinic for subcutaneous administration of casirivmab and imdevimab (REGEN-COV; Regeneron) for treatment of patients with symptomatic mild to moderate coronavirus disease 2019 (COVID-19) in terms of preventing disease progression and healthcare utilization. Methods This retrospective single-center, propensity-matched cohort study examined healthcare utilization outcomes for patients who received subcutaneous casirivimab and imdevimab at a pharmacist-led clinic of an academic health system. Eligible patients were treated between August 1, 2021, and January 5, 2022, and were at high risk for COVID-19 disease progression. Treatment patients were propensity matched with high-risk control patients with a diagnosis of COVID-19 in the same timeframe who did not receive casirivimab and imdevimab. Patients were followed for 30 days for collection of data on inpatient admissions, emergency department visits, and mortality. Risk of a 30-day healthcare utilization event was assessed and tested for statistical significance utilizing McNemar’s test. Results A total of 585 patients who received treatment with subcutaneous casirivimab and imdevimab were matched with 585 patients who did not receive casirivimab and imdevimab therapy. Patients who received casirivimab and imdevimab had significantly lower risk of a 30-day all-cause inpatient admission event than untreated patients (relative risk reduction, 61.2%; P < 0.0001). Treated patients also had a significantly lower risk of 30-day all-cause emergency department visit than untreated subjects (relative risk reduction, 36.6%; P = 0.0021). There were 6 mortality events in the untreated group and no mortality events in the treatment group. Conclusion This study provides evidence for the effectiveness of a subcutaneous casirivimab and imdevimab clinic in preventing progression of symptomatic mild to moderate COVID-19.

Development of a neutralization monoclonal antibody with a broad neutralizing effect against SARS-CoV-2 variants

“…Thirty-one common mutations were found in the S protein of B.1.1.529, and S477R, Q498R, and N501Y substitutions increased the binding ability to the hACE2 receptor, while K417N increased the ability to avoid neutralizing antibodies [ 25 ]. Particularly, treatment with mAbs, such as bamlanivimab [ 26 ], etesevimab [ 27 ], casirivimab [ 28 ], and imdevimab [ 29 ], did not neutralize the variants. However, SKAI-DS84 exhibited slight variations in efficacy depending on the VOC, but it was able to neutralize not only the WT but also the currently circulating VOCs.…”

Casirivimab-imdevimab treatment is associated with reduced rates of mortality and hospitalization in patients with COVID-19: A systematic review with meta-analysis

“…Through a thorough literature search, a total of nine studies, including 84875 in the casirivimab-imdevimab group and 322,943 in the control group arm, were identified for this meta-analysis. 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 Table 1 lists the illness features and demographics of the 407818 patients who were included in the pooled study. The majority of the included studies were from the United States.…”

“…Three studies included COVID-19 individuals who were all outpatients. 4 , 5 , 6 Casirivimab-imdevimab was given intravenously or subcutaneously in the included studies. The selected studies, which were all published between 2022 and 2023, had various sample patient sizes ranging from 152 to 384,447 patients with COVID-19.…”