A Randomized Controlled Study Assessing Convalescent Immunoglobulins vs Convalescent Plasma for Hospitalized Patients With Coronavirus 2019

Background. It is unknown whether convalescent immunoglobulins (cIgGs) are better than convalescent plasma (CP) for patients with coronavirus 2019. Methods. In this randomized controlled trial, high-risk COVID-19 patients with ≤10 days of symptoms were assigned to receive cIgGs or CP. The primary endpoint was improvement on day 14 according to the World Health Organization (WHO) scale. Secondary endpoints were survival on day 14, and improvement, survival, and percent ventilated on day 28, plus subgroup analyses by vaccination status. Results. 319 patients were included: 166 received cIgGs and 153 CP. Median age 64–66 years. A total of 112 (67.5%) in the cIgG group and 103 (67.3%) in the CP group reached the primary endpoint (difference 0.1; 95% CI, −10.1 to 10.4; P = .026), failing to reach noninferiority. More patients receiving cIgG improved by day 28 (136 [81.9%] vs 108 [70.6%]; 95% CI, 1.9–20.7; P < .001; superiority P = .018). Mechanical ventilation was required in 10.2% vs 16.3% (P = .136); mortality 9.6% vs 15% (P = .172) for cIgG vs CP, respectively. In unvaccinated patients, more improved by day 28 with cIgG (84.1% vs 66.1%; P = .024), and survival was better (89.9% vs 77.4%; P = .066). Conclusions. cIgGs failed to reach the primary noninferiority endpoint on day 14 but were superior to CP on day 28; unvaccinated patients particularly benefited. cIgGs are a viable option for treating COVID-19 amid emerging variants. Trial registration: My Trials MOH_2021-01-14_009667.