Convalescent plasma therapy fails to reduce mortality in patients with severe COVID-19
Convalescent plasma treatment can discontinue severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) shedding, but cannot reduce mortality in critically ill patients with end-stage coronavirus disease 2019 (COVID-19), according to a study published in The Journal of Infectious Diseases.
Qing-Lei Zeng, MD, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China, and colleagues reported outcomes from 21 critically ill patients with COVID-19 admitted to the intensive care unit who either did not receive (n = 15) or received (n = 6) convalescent plasma treatment.
Convalescent plasma was obtained from individuals who had recovered from COVID-19. All donors were negative for the testing of SARSCoV-2 RNA and IgM, and positive for IgG testing before donations.
Of the 6 patients in the convalescent plasma group, 5 died, as did 14 of the 15 patients in the control group (P = 0.184). Each group only had 1 patient who recovered.
All the 6 patients in the treatment group obtained viral clearance after convalescent plasma transfusions, and 100% (5/5) of fatal patients in the treatment group had undetectable SARS-CoV-2 before death in treatment, as did 21.4% (3/14) of fatal patients in the control group (P = 0.005).
“A recent study indicated that SARS-CoV-2 was detectable until death in non-survivors , and whether undetectable SARS-CoV-2 before death can regress fatalities is unknown,” the authors wrote. “In [the] current study, to the best of our knowledge, we firstly indicate that [treatment with] convalescent plasma contributes to the discontinuation of SARS-CoV-2 shedding…[but] it cannot reduce the mortality in critically [ill patients with] end-stage COVID-19.”
The authors noted that, in most acute viral diseases, viremia peaks in the first week after infection and patients usually develop a primary immune response by day 10 to 14, which is followed by virus clearance. After this time-point, if a patient’s status deteriorates, it is usually the result of inflammatory or hyperimmune attacks rather than direct viral-induced tissue damage.
“Hence, convalescent plasma should theoretically be more effective when given in the early course of disease (before day 14, or during the viremic and seronegative stage),” the authors wrote. “The failure of convalescent plasma to reduce mortality may be attributed to the timing of transfusion, which were given on median day 21.5 during viral shedding. On the contrary, one critical patient in the treatment group infused on day 11 during viral shedding was finally recovered.”