A systematic review of convalescent plasma treatment for COVID19
Background. Transfusion of convalescent immune plasma (CP) is commonly used in epidemics. Several articles now describe clinical report data of CP for treatment of SARS CoV 2 induced COVID 19 disease. Methods. A systematic literature review was conducted using the NCBI curated COVID 19 related open resource literature database LitCovid to identify studies using CP as treatment for COVID 19 patients. We retrieved and curated all COVID 19 related patient and treatment characteristics from previously reported studies. A Poisson model was developed to evaluate the association between age of the patients, older age being the most common risk factor for COVID 19 mortality, and recovery time since CP treatment using data extracted from the literature. Results. From 18,293 identified COVID 19 related articles, we included ten studies reporting results of CP treatment for COVID 19 from a total of 61 patients. Decreased symptoms of severe COVID 19 and clearance of SARS CoV 2 RNA were the most direct observations. We found that patients over the age of sixty who received CP treatment for COVID 19 had a significantly prolonged recovery estimated by viral clearance (from 10 to 29 days since first dose of CP) compared to younger patients, who recovered from the infection in less than a week after receiving CP treatment. Conclusions. Limited published results on plasma transfusion treatment for COVID 19 disease with concomitant treatments suggest that CP therapy for COVID 19 is well tolerated and effective. First randomized clinical trial results, however, reveal no improvements in recovery time for elderly patients with severe COVID 19 between standard treatment alone and added with convalescent plasma. Accordingly, we argue that older patients may need a significantly longer time for recovery. Further randomized clinical trial data for COVID 19 with rigorous ethical standards is urgently needed.
medRxiv