Researchers from the University of California, San Diego (UCSD) School of Medicine and UC San Diego Health launched a clinical trial this Monday investigating the safety and efficacy of convalescent plasma (CP) to prevent COVID-19 after a known exposure to the virus. The UCSD study is a part of a larger, national trial approved by the U.S. Food and Drug Administration (FDA). Sponsored by the National Institute of Health (NIH) via the Department of Defense (DOD), the national trial is coordinated by Johns Hopkins University. The goal here is to create a network of hospitals and blood banks collecting, isolating, processing, and testing whether plasma from COVID-19 survivors has therapeutic and preventive value.
Edward Cachay, an infectious disease specialist at UCSD School of Medicine, reports, “With convalescent plasma, we want to act prophylactically, using a product with known high-titers (concentrations) of neutralizing antibodies.” He continued “We want to learn how we can prevent sickness, how we can prevent COVID patients from needed mechanical ventilation and how we can present them from dying from the disease.”
UCSD reports that generally convalescent plasma has proven safe however its true effectiveness has varied, for example, depending on disease type. For example, studies involving convalescent plasma therapies for Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS).
And the 2009 H1N1 influenza evidenced measurable reductions in mortality (compared to placebo or no therapy); however initiative to address and apply to Ebola virus infections during the 2014-16 outbreak in West Africa were inconclusive.
Chinese researchers report some limited success using convalescent plasma in non-randomized controlled studies. Not the gold standard, but nonetheless in a pandemic situation research communities are studying activities where relevant around the world.
It appears that the human immune system initiates producing antibodies to the disease five to ten days post infection. These antibodies then bind to the targeted coronavirus (SARS-CoV-2), blocking them from latching onto new cells and initiating the replication process. According to the UCSD Health News Room’s press release, the human body initiates the clearing out of SARS-CoV-2 over the course of two or so weeks. But antibodies to it, meaning the blueprint or instructions for making them persist. A big question mark remains the depth and length of subsequent immunity.
Professor Cachay argues that convalescent plasma most likely will work better in individuals with early exposure to SARS-CoV-2 prior to the actual appearance of symptoms. But he recognizes that they must collect and analyze clinical trial data to substantiate this premise. Importantly he communicated, “If we don’t do this, if we just gather anecdotal evidence that isn’t conclusive, then we won’t be any better off when the next wave hits.”
The UC San Diego Health clinical trial involves a total of 487 qualifying participants for the study. Criteria to qualify for participation includes a high-risk factor, such as age or an underlying condition, such as cardiovascular disease, diabetes, existing pulmonary impairment or employment as a health care worker as well as known exposure to SARS-CoV-2; also a negative PCR diagnostic test to evidence no infection.
The sponsor will set up tents across from the emergency department at Jacobs Medical Center and the Altman Clinical and Translational Research Institute (ACTRI) on the La Jolla campus. The UC Health Blood Bank is coordinating efforts with the San Diego Blood Bank. The ACTRI offers up the personnel, infrastructure support and other resources for the convalescent plasma trial and for other COVID-19 related clinical trials at UC San Diego. Moreover, ACTRI has launched a COVID-19 Biobank to provide materials for research projects to diagnose or treat the disease.
Edward Cachay, Professor of Clinical Medicine
Call to Action: If you are based in the San Diego area and interested in participating in this study, please contact Donna Brusch, senior study coordinator at [email protected] or call 760-505-6649. The process includes an ongoing screening step. The UC San Diego clinical trial commences Monday, July 13, 2020.