Publications

Convalescent Plasma Reduces Hospitalizations for Outpatients with Recent COVID-19 Infection

In the setting of the public health catastrophe brought on by COVID with limited therapeutic interventions initially available, new and old therapies were evaluated to avert further death and disability. COVID-19 convalescent plasma (CCP) became one of the most common therapies early in the pandemic with more than 100,000 units distributed to hospitals every month just in the United States. However, limited data were available on the efficacy. Physician-scientists at Johns Hopkins noted that convalescent plasma for other infectious disease outbreaks was historically most effective when provided early and the units contained high titers. Thus, a multi-center randomized trial was initiated to evaluate whether high-titer CCP provided to outpatients infected with COVID-19 could prevent hospitalization. In the trial, 1225 participants were randomized, and 1181 received either CCP or control arm standard plasma. CCP reduced hospitalizations by 54% if provided within nine days of symptoms onset and reduced hospitalizations by >80% if transfused within five days of symptom onset. In the current setting with vaccines and substantial population-based immunity, CCP is likely most beneficial to the immunosuppressed patients and those most vulnerable to severe disease progression.