The results of a nationwide, multicenter clinical trial led by Johns Hopkins Medicine and the Johns Hopkins Bloomberg School of Public Health provides solid evidence for the use of plasma from convalescent patients—those who have recovered from the disease and whose blood contains antibodies against SARS-CoV-2, the virus that causes COVID-19—as an early treatment. The researchers showed that convalescent plasma reduced the need for hospitalization by half for outpatients with COVID-19 who participated in the study.