ABSTRACT
CT-P59, a monoclonal antibody with potent neutralizing activity against severe acute respiratory syndrome coronavirus 2, may ameliorate symptoms and prevent hospitalization in outpatients with mild-to-moderate disease. We report findings from part one of a two-part randomized, placebo-controlled, double-blind study (NCT04602000; EudraCT: 2020-003369-20). Outpatients with mild-to-moderate COVID-19 received a single dose of CT-P59 40 mg/kg (n=101), CT-P59 80 mg/kg (n=103), or placebo (n=103). Median (95% confidence interval [CI]) time to conversion to negative RT-qPCR result (coprimary endpoint) was 12.8 days (9.00–12.84) with CT-P59 40 mg/kg, 11.9 days (8.94–12.91) with CT-P59 80 mg/kg, and 12.9 days (12.75–13.99) with placebo. Median (95% CI) time to clinical recovery (coprimary endpoint) was 5.4 days (3.97–6.78) with CT-P59 40 mg/kg, 6.2 days (5.53–7.85) with CT-P59 80 mg/kg, and 8.8 days (6.72–11.73) with placebo. The proportion (95% CI) of patients requiring hospitalization or oxygen therapy was lower with CT-P59 40 mg/kg (4.0% [1.6–9.7%]) and CT-P59 80 mg/kg (4.9% [2.1–10.9%]) versus placebo (8.7% [4.7–15.8%). CT-P59 was well tolerated and no serious treatment-emergent adverse events or deaths occurred. In summary, CT-P59 accelerated viral and clinical recovery from COVID-19 and was well tolerated in patients with mild-to-moderate infection.