The effectiveness of convalescent plasma administered on the first day of admission for COVID-19 patients: an open-label randomized controlled trial

Abstract Background: Given the controversial reports on the effect of convalescent plasma (CP) on coronavirus disease 2019 (COVID-19) patients, this study aimed to clarify the efficacy of early CP administration, improve the understanding of its impact on clinical outcomes, guide future research, address safety concerns, and inform public health policies. Methods: In this prospective, multicenter, randomized controlled trial conducted at Razi Hospital (Ahvaz) and Bouali Hospital (Zahedan) in Iran, 232 confirmed COVID-19 patients were randomly assigned into two groups using a computer-generated randomization method. The treatment group ( n = 116) received CP with anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) IgG titer ≥1/160 on the first day of admission, along with routine antiviral medications, while the control group received only routine medications ( n = 116). Recruitment occurred from 1 March to 30 July 2020, with two months of post-intervention follow-up. The primary outcome was two-month mortality, and secondary outcomes included CP-related side effects and various clinical and laboratory parameters. Results: No significant differences were observed between the groups in terms of age ( P = 0.119), sex ( P = 0.418), comorbidities ( P > 0.05), or pre- and post-treatment changes in temperature, lymphocyte count, erythrocyte sedimentation rate, or platelet count (all P > 0.05). Despite a higher CT severity score at admission in the treatment group ( P < 0.001), improvements in respiratory rate, C-reactive protein, and lactate dehydrogenase occurred earlier and were more pronounced compared to the control group ( P < 0.05). No side effects related to CP therapy were observed during infusion or follow-up. However, no significant differences were observed between the groups in the mortality rate or length of hospitalization. The mortality rate in the treatment group was 11.2% (13/116), compared to 17.2% (20/116) in the control group ( P = 0.130). The median hospital stay was 7 days (95% CI : 6–8 days) for the treatment group and 6 days (95% CI : 5–7 days) for the control group ( P = 0.560). Conclusion: While administering CP with a high titer of anti-SARS-CoV-2 IgG early in infection may improve vital signs and laboratory parameters in COVID-19 patients, it does not significantly reduce mortality risk or length of hospitalization compared to routine medications. Overall, the treatment appears to have few side effects, suggesting it may be a safe option for further evaluation in managing early COVID-19 symptoms. Trial registration: This prospective, multicenter, two-parallel randomized controlled trial was prospectively registered in the Iranian Clinical Trials Registry (IRCT20200310046736N1).