Because the optimal treatment for COVID-19 is still unknown, it is important to explore every potential way of improving the chances of survival for COVID-19 patients. The aim of the study was to analyze the effectiveness of convalescent plasma on COVID-19 patients. The study population consisted of 78 patients diagnosed with COVID-19, selected from the SARSTer national database, who received convalescent plasma. The impact on clinical and laboratory parameters was assessed. A clinical improvement was observed in 62 (79%) patients, and 10 (13%) patients died from COVID-19. No side effects of the convalescent plasma treatment were observed. When plasma was administered earlier than 7 days from diagnosis, the total hospitalization time was shorter (p < 0.05). Plasma efficacy was inferior to remdesivir in endpoints such as the necessity and duration of oxygen therapy, the duration of hospitalization, and mortality rate, and inferior to other drugs in the case of the duration of hospitalization and the necessity of constant oxygen therapy, but comparable in most other measured endpoints. A comparison of a 30-day mortality rate in patients who received plasma and remdesivir (4/25, 16%) and who received only plasma (6/53, 11%) showed no significant difference. Convalescent plasma efficacy is inferior to remdesivir when treating COVID-19 patients but the addition of remdesivir to plasma does not improve the treatment effectiveness. In most endpoints, plasma was comparable to other treatment options. In our opinion, convalescent plasma may be used as a supportive treatment in COVID-19 patients because of the low frequency of adverse effects and availability, but must be given as early from the diagnosis as possible.
Keywords: COVID-19; convalescent plasma; transfusion.