Subcutaneous Monoclonal Antibodies as good as IV infusion for reducing hospitalization in Covid-19: JAMA

Subcutaneously given casirivimab and imdevimab to high-risk outpatients with mild to severe COVID-19 symptoms was linked with lower hospitalization and mortality as compared to no therapy, says an article published in the Journal of American Medical Association.

Treatment with monoclonal antibodies (mAbs) reduces hospitalization and death in elevated outpatients with minor to moderate COVID-19; however, only intravenous delivery has been studied in randomized clinical trials. Subcutaneous administration may increase outpatient treatment capacity and the number of skilled professionals available to provide therapy, although the relationship with patient outcomes is unknown. Erin K. McCreary and her colleagues carried out this research. To see if subcutaneous casirivimab and imdevimab treatment reduces 28-day hospitalization and death compared to nontreatment in mAb-eligible patients, and if subcutaneous casirivimab and imdevimab intervention is clinically and statistically comparable to intravenous casirivimab and imdevimab treatment.

From July 14 to October 26, 2021, high-risk outpatients in a learning health system in the United States with mild to moderate COVID-19 symptoms who were eligible for mAb therapy under emergency use authorization were assessed in this prospective cohort research. In addition, an untreated control group of eligible individuals was evaluated. The intervention strategy was subcutaneous injection or intravenous administration of a combination single dosage of 600 mg casirivimab and 600 mg imdevimab. The 28-day adjusted risk ratio or adjusted risk difference for hospitalization or death was the main outcome. Secondary outcomes were 28-day adjusted risk ratios and hospitalization differences, mortality, a composite end point of emergency department admission and hospitalization, and adverse event rates.

The key findings of this study were as follow:

1. Amongst 1959 matching adults with mild to moderate COVID-19, 969 patients who took casirivimab and imdevimab subcutaneously had a 28-day hospitalization or mortality rate of 3.4% compared to 7.0% in untreated controls.

2. The 28-day rate of hospitalization or death was 2.8% versus 1.7% among 2185 patients treated with subcutaneous (n = 969) or intravenous casirivimab and imdevimab, resulting in an adjusted risk difference of 1.5 percent.

3. There was no difference in critical care unit hospitalization or the need for mechanical breathing among all infusion patients.

In conclusion, collectively, these results provide preliminary evidence of potential expanded use of subcutaneous mAb treatment, particularly in areas facing treatment capacity and/or staffing shortages.

Reference:

McCreary EK, Bariola JR, Wadas RJ, et al. Association of Subcutaneous or Intravenous Administration of Casirivimab and Imdevimab Monoclonal Antibodies With Clinical Outcomes in Adults With COVID-19. JAMA Netw Open. 2022;5(4):e226920. doi:10.1001/jamanetworkopen.2022.6920