After finding no benefit, the international REMAP-CAP trial testing convalescent plasma for the treatment of patients with COVID-19 has halted enrollment of patients with severe illness requiring intensive care unit (ICU) support.
An initial analysis of more than 900 trial participants with severe COVID-19 enrolled in REMAP-CAP showed that treatment with plasma from patients who have recovered from infection did not improve outcomes. Researchers found only a 2.2% probability that convalescent plasma reduced death rates or decreased the number of days that patients required ICU support.
“It is biologically plausible that patients who are not producing antibodies at the time of convalescent plasma therapy and those patients with excess virus may benefit more than others,” said Manu Shankar-Hari, MD, PhD, coleader of the trial and a clinician and professor of critical care medicine at Guy’s and St. Thomas’ hospital in London. “Our additional analyses will explore this.”
“Why convalescent plasma does not seem to improve outcome in severely ill COVID-19 patients admitted to the ICU is not yet known. However, it may be because the lung damage is too advanced for convalescent plasma to make a difference,” commented Alexis Turgeon, MD, study coauthor and critical care doctor and professor at Université Laval in Quebec, Canada.
There was no evidence of harm associated with the administration of convalescent plasma, the investigators added, and the trial continues to enroll patients who are hospitalized with moderate illness but do not require ICU support.
The REMAP-CAP trial has recruited 4,100 patients with COVID-19 from more than 290 clinical sites across the Americas, Europe, Asia, Africa, and Australasia. Researchers are also evaluating a range of other therapies, including anticoagulants, antiplatelet agents, antibiotics, statins, and vitamin C.