Risk factors for progression to acute respiratory failure after casirivimab and imdevimab administration: A retrospective study

BACKGROUND: Casirivimab and imdevimab are effective in preventing hospitalization in outpatients with coronavirus disease 2019 (COVID-19); however, disease progression after casirivimab and imdevimab administration has been reported. This study aimed to elucidate the risk factors for disease progression after casirivimab and imdevimab administration. METHODS: This retrospective study included patients with COVID-19 who received casirivimab and imdevimab at Hiroshima City Funairi Citizens Hospital between August 6, 2021, and October 10, 2021. All patients had at least one risk factor for severe disease and were treated on admission. The patients’ background characteristics and test results at the first visit were analyzed. The patients were divided into two groups (progressed and improved) based on whether they progressed to acute respiratory failure during hospitalization. RESULTS: Sixty-seven patients were included: 9 patients in the progressed group (median age, 56 years) and 58 patients in the improved group (median age, 51 years). Age, coexistence rate of diabetes, cycle threshold value of polymerase chain reaction test, rate of detectable pneumonia on chest radiographs or chest computed tomography images, lymphocyte count, and the levels of C-reactive protein, interleukin-6, glucose, and glycated hemoglobin were significantly different between the two groups. Multivariate logistic regression analysis revealed that the coexistence of diabetes and the presence of detectable pneumonia on chest radiographs were independent factors predicting the progression to acute respiratory failure. CONCLUSION: Acute respiratory failure after antibody therapy with casirivimab and imdevimab may develop in patients with diabetes or detectable pneumonia on chest radiographs at the first visit.