On Mar. 26, 2020, Cerus announced it had formed a collaborative research group with the aim of optimizing convalescent plasma therapy for COVID-19 patients. The research group seeks to define the key characteristics that influence the efficacy of convalescent plasma, including the level and nature of anti-COVID-19 antibodies, optimal collection timing, dosing and how these influence responses to the therapy regimen.

Cerus’ research group collaborators include the California Department of Public Health, the University of California, Irvine’s Vaccine Development Research Laboratory, the Vitalant Research Institute, the California National Primate Research Center, and Enable Biosciences.

As the number of convalescent or asymptomatic COVID-19 individuals in the community increases, the sources of convalescent plasma become more abundant. Data from China indicate that antibodies collected from recovered COVID-19 patients can prevent infection of cells, and protect against infection in a COVID-19 primate model. During an earlier SARS epidemic, patients who received convalescent plasma with antibodies to SARS recovered more rapidly.

Some convalescent plasma therapies have been produced using pathogen reduction technology, such as Cerus’ INTERCEPT Blood System, to reduce the risk of other viruses, bacteria, and parasites that could be present in the convalescent plasma donation. The INTERCEPT plasma system has approved label claims for SARS-CoV inactivation in both the US and Europe. SARS-CoV-2 is the causative agent of COVID-19 and the genetic sequence is at least 70% similar to that of SARS-CoV.

Passive immunity has proven effective for cytomegalovirus (CMV), hepatitis B virus, rabies, tetanus, varicella, certain SARS variants, Argentine Hemorrhagic Fever, and various other illnesses. Convalescent plasma has been cited as a potential therapy for viral infection dating back to the 1918 Spanish influenza A (H1N1) pandemic. Since that time, convalescent plasma as passive immune therapy has been evaluated in the treatment of: Ebola, SARS coronavirus (SARS-CoV), 2009 pandemic influenza A (H1N1), Argentine Hemorrhagic Fever, CMV, Parvovirus B19, and others.