Willis-Knighton conducts clinical trial for COVID-19 therapy; donors wanted Fri, 04/17/2020 - 12:00am Willis-Knighton Health System has begun a clinical trial of the use of convalescent plasma therapy as an experimental treatment of ...PLEASE LOG IN FOR PREMIUM CONTENT. Our website requires visitors to log in to view the best local news. Not yet a subscriber? Subscribe today! Read more about Willis-Knighton conducts clinical trial for COVID-19 therapy; donors wanted