Passive Immunization and Its Rebirth in the Era of the COVID-19 Pandemic

The COVID-19 pandemic, caused by SARS-CoV-2, has led to a rapid search for therapeutic and preventive measures because of the potentially severe course of infection. The antiviral drug, remdesivir, and the anti-inflammatory agent, dexamethasone, have shown beneficial effects. As the current COVID-19 vaccines are not yet fully available to everyone, or they may not be readily and universally accepted, various treatment options are being evaluated and will still be needed under these conditions. One of these treatment options, passive immunization, has shown promise in some studies. Further research is needed to determine the utility of immunotherapy with convalescent plasma or artificially produced monoclonal antibodies for the treatment of symptomatic patients, and potentially for use as post-exposure prophylaxis, at least until more effective drugs are available or safe and effective vaccines are distributed and administered to everyone.