Variant of Concern-Matched COVID-19 Convalescent Plasma Usage in Seronegative Hospitalized Patients

• Main Authors: Arar, O. (Author), Baldanti, F. (Author), Ballotari, A. (Author), Beccaria, M. (Author), Bertacco, S. (Author), Ferrari, A. (Author), Focosi, D. (Author), Franchini, M. (Author), Gagliardo, T. (Author), Garuti, M. (Author), Ghirardini, M. (Author), Glingani, C. (Author), Greco, G. (Author), Pecoriello, A. (Author), Percivalle, E. (Author), Sammartino, J.C (Author), Santini, T. (Author), Schiavulli, M. (Author), Spreafico, F. (Author), Stefania, M. (Author), Zani, M. (Author)
• Format: Article
• Language: English
• Published: MDPI 2022
• Subjects: COVID-19 convalescent plasma; efficacy; SARS-CoV-2; variants of concern
• Online Access: View Fulltext in Publisher

 COVID-19 convalescent plasma (CCP) has been the only specific anti-viral therapy against SARS-CoV-2 available for more than one year. Following the negative results from most randomized controlled trials on its efficacy in COVID-19 hospitalized patients and the availability of anti-spike monoclonal antibodies (mAbs), the use of CCP has subsequently rapidly faded. However, the continuous appearance of new variants of concern (VOCs), most of which escape mAbs and vaccine-elicited neutralizing antibodies (nAbs), has renewed the interest towards CCP, at least in seronegative immunocompetent patients, and in immunocompromised patients not able to mount a protective immune response. We report here the experience of a single Italian hospital in collecting and transfus-ing CCP in immunocompromised patients hospitalized for severe COVID-19 between October 2021 and March 2022. During this 6-month period, we collected CCP from 32 vaccinated and convalescent regular blood donors, and infused high nAb-titer CCP units (titered against the specific VOC affecting the recipient) to 21 hospitalized patients with severe COVID-19, all of them seronegative at the time of CCP transfusion. Patients’ median age was 66 years (IQR 50–74 years) and approximately half of them (47.6%, 10/21) were immunocompromised. Two patients were rescued after previous failure of mAbs. No adverse reactions following CCP transfusion were recorded. A 28-day mortality rate of 14.3 percent (3/21) was reported, with age, advanced disease stage and late CCP transfusion associated with a worse outcome. This real-life experience also supports the use of CCP in seronegative hospitalized COVID-19 patients during the Delta and Omicron waves. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.