Convalescent Plasma Therapy in Severe COVID-19: A Pilot Study at the Beginning of the Pandemic Outbreak in Southern Chile.

Convalescent Plasma (CP) from patients who recovered from COVID-19 may present neutralizing antibodies against viral protein S of SARS-CoV-2 and emerged as a potential therapeutic alternative for patients with severe infection at the beginning of the COVID-19 pandemic breakout. Thus, this study aimed to evaluate the effect and safety of CP treatment in patients with severe COVID-19.

Methods: We designed a quasi-experimental study that included 156 patients with SARS-CoV-2 infection confirmed by RT-qPCR and severe symptoms who received CP. As a control group, we selected a historical cohort of 113 individuals admitted with COVID-19 and severe symptomatology before the starting date of the study. Clinical status and mortality during the study period were recorded.

Results: There were no adverse reactions to CP administration. In the CP group, days on mechanical ventilation were significantly lower than the control group (2.8±5.08 days vs. 4.7±6.19 days; p= 0.0081). Moreover, a significant difference was observed in the number of days stayed in the critical patient unit (CPU) in CP vs. controls (4.2±5.47 vs. 5.8±6.39 days, p= 0.0281).

Conclusions: We observed no association between CP administration and survival at 14 days. Treatment with CP was safe and not associated with adverse events. In addition, using CP was associated with a reduction in both stay at the CPU and connection to mechanical ventilation.