Convalescent Plasma Transfusion for Treatment of Corona Virus Disease 2019 (COVID-19) Infection-: A Systematic Review

Abstract

Based on the concept of passive immunization, the convalescent plasma is likely to contain high levels of neutralizing antibodies against the SARS-CoV-2 virus, which, when transfused to patients with acute COVID-19 infection, can provide a degree of passive immunity. Our initial search yielded 5944 citations then based on the selection criteria, 23 articles were eligible including 8 RCTs and 15 NRSIs. All studies reported some benefits after CPT performance, but most NRSIs had risk of bias owing to a combination of confounding factors such as selection bias and variation in dosage and duration of CPT. Twelve studies reported minor adverse effects and only 4 studies reported major side effects while there was no observed side effects in 7 studies. CPT significantly reduced mortality in only 3 RCTs and 5 NRSIs. Eleven studies evaluated the effect of plasma transfusion on clinical improvement at day 14 and day 28, only one RCT and 6 NRSIs reported statistically significant benefit of CP. Time to clinical improvement was reported in 7 studies, there was significantly less time to clinical improvement in plasma group compared to control group in one RCT and in one NRSI. The average of Hospital length of stay was reported in 15 studies comparing CPT group versus control group and they reported that CPT could significantly decrease the hospital length of stay in only 3 NRSIs studies. Rate of hospital discharge was also evaluated in 7 studies, but there is no significant difference in each of them between the two groups. Three RCTs studies showed that there was significantly decrease in viral load in plasma group versus control group in one RCT. ICU length of stay was discussed in 5 NRSIs studies and it is decreased with significant difference in only 2 studies in CPT group. In our review, findings suggest that early initiation of treatment with high IgG titer may be of critical importance to reducing mortality in patients especially when administrated early.