Convalescent plasma in hospitalized patients with COVID-19 pneumonia: a case-control prospective study

Background: This case-control prospective study aimed to describe the effects of COVID convalescent plasma (CCP) therapy in patients diagnosed with coronavirus disease 2019 (COVID-19) pneumonia due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, during the fourth trimester of 2020 in Venice Prefecture (North East Italy). Methods: Overall, 214 consecutive patients admitted to COVID-19 Hospitals of our district were enrolled. The confirmation of SARS-CoV-2 infection was made through the reverse transcription-polymerase chain reaction test in nasopharyngeal swabs. The severity of each patient’s clinical condition was determined following the Berlin score. The clinical data, laboratory test reports and imaging diagnosis of all patients were analyzed at hospitalization. All subjects were showing symptoms of severe COVID-19 pneumonia and were treated with conventional therapy;108 patients received standard therapy and 106 received standard therapy in combination with CCP. The endpoint was mortality at 30 days. Results: The two patient series were comparable for gender, age, risk factors, Berlin score, PaO2/FiO2. Both groups received standard therapy: NSAIDs, ventilator support, LMWH, steroids, antibiotics and antivirals;106 subjects were additionally administered CCP. The mortality rate at 30 days was 30.6% among subjects treated with standard therapy versus 30.2% among subjects treated with standard therapy plus CCP. Considering the radiological findings and ventilatory support data, it would appear that the disease was more severe in patients treated with ST plus CCP. Conclusions: This case-control prospective study showed that in a cohort of hospitalized patients suffering from severe COVID-19 pneumonia, the addition of CCP to the standard therapy did not impact the mortality rate at 30 days. However, we believe that further studies are needed to evaluate the effectiveness of convalescent plasma therapy.