Dr. David Fajgenbaum, of the University of Pennsylvania, spoke with Boston Public Radio on Monday about his personal experience battling and researching Castleman disease, a disease with similar effects to COVID-19.

"The clinical experience of a patient with a very severe case of COVID-19 and with a case of Castelman disease is almost indistinguishable — you get the same sort of multiple organ failure," he said. "The cause of it is excessive production of cytokines, these molecules your immune system uses to communicate with other immune cells."

When cytokine levels rise too high, you get very sick, Fajgenbaum added.

"So I redirected my lab, primarily focused on Castleman disease, to focus on COVID-19," he said. "We can't wait for a new drug to be developed, so we need to look at drugs that already exist and repurpose them for COVID-19."

Dr. David Fajgenbaum, MD, MBA, MSc, FCPP, is the co-founder and Executive Director of the Castleman Disease Collaborative Network (CDCN), Assistant Professor of Medicine in Translational Medicine & Human Genetics at the University of Pennsylvania, Associate Director, Patient Impact for the Penn Orphan Disease Center, and author of "Chasing My Cure: A Doctor's Race to Turn Hope Into Action; A Memoir."