Convalescent Plasma Therapy for Coronavirus Disease 2019

Convalescent plasma has been used for decades to prevent and treat a wide range of infectious diseases for which no specific treatment is available. The use of convalescent plasma involves transfusing plasma collected from patients who have recovered from a viral illness, in an attempt to transfer virus-neutralizing antibodies and confer passive immunity. In addition to the antiviral mechanisms of neutralizing antibodies, the immunomodulatory effects of plasma components could have benefits. Several small and large-scale studies have shown the effects of convalescent plasma for the treatment of severe coronavirus disease 2019 (COVID-19). In addition to transfusion-related side effects, unexpected side effects such as antibody-dependent enhancement (ADE) may occur during convalescent plasma therapy, but early safety studies have not found any cases of ADE among more than 5,000 participants. With historical precedents and recent clinical studies, convalescent plasma therapy should be considered as a candidate therapy for COVID-19 given the limited effectiveness of antiviral drugs and lack of a vaccine. A system to secure safe collection and use of convalescent plasma should be developed as a response to the pandemic. Further clinical trials should be conducted to determine the safety and efficacy of convalescent plasma therapy concurrently with its clinical use.