early stage of disease): Comparator: nonCP (fresh frozenplasma collected before December 2019) Concomitant therapy: NR Treatment crossovers: no Primary study outcome: time to improvement Primary review outcomes Allcause mortality at hospital discharge: time from randomisation to clinical improvement of 1 1 point on a 7category ordinal scale or alive discharge from the hospital, whichever comes first. immunoglobulin for people with COVID19, irrespective of study design, disease severity, age, gender or ethnicity. We excluded studies including populations with other coronavirus diseases (severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS)) and studies evaluating standard immunoglobulin. == Data collection and analysis == We followed standard Cochrane methodology. To assess bias in included studies, we used the Cochrane ‘Risk of bias’ tool for randomised controlled trials (RCTs), the Risk of Bias in Nonrandomised Studies of Interventions (ROBINSI) tool for controlled nonrandomised studies of interventions (NRSIs), and the assessment criteria for observational studies, provided by Cochrane Childhood Cancer for noncontrolled NRSIs. == Main results == This is the first living update of our review. We included 20 studies (1 RCT, 3 controlled NRSIs, 16 noncontrolled NRSIs) with 5443 participants, of whom 5211 received convalescent plasma, and identified a further 98 ongoing studies evaluating convalescent plasma or hyperimmune immunoglobulin, of which 50 are randomised. We did not identify any completed studies evaluating hyperimmune immunoglobulin. Overall risk of bias of included studies was high, due to study design, type of participants, and other previous or concurrent treatments. Effectiveness of convalescent plasma for people with COVID19 We included results from four controlled studies (1 RCT (stopped early) with 103 participants, of whom 52 received convalescent plasma; and 3 controlled NRSIs with 236 participants, of whom 55 received convalescent plasma) to assess effectiveness of convalescent plasma. Control groups received standard care at time of treatment without convalescent plasma. Allcause mortality at hospital discharge (1 controlled NRSI, 21 participants) We are very uncertain whether convalescent plasma has any effect on allcause mortality at hospital discharge (risk ratio (RR) 0.89, 95% confidence interval (CI) 0.61 to 1 1.31; very lowcertainty evidence). Time to death (1 RCT, 103 participants; 1 controlled NRSI, 195 participants) We are very uncertain whether convalescent plasma prolongs time to death (RCT: hazard ratio (HR) 0.74, 95% CI 0.30 to 1 1.82; controlled NRSI: HR 0.46, 95% CI 0.22 to 0.96; very lowcertainty evidence). Improvement of clinical symptoms, assessed by need for respiratory support (1 RCT, 103 participants; 1 controlled Auristatin F NRSI, 195 participants) We are very uncertain whether convalescent plasma has any effect on improvement of clinical symptoms at seven days (RCT: RR 0.98, 95% CI 0.30 to 3.19), 14 days (RCT: RR 1.85, 95% CI 0.91 to 3.77; controlled NRSI: RR 1.08, 95% CI 0.91 to 1 1.29), and 28 days (RCT: RR 1.20, 95% CI 0.80 to 1 1.81; very lowcertainty evidence). Quality of life No studies reported this outcome. Safety of convalescent plasma for people CDC25A with COVID19 We included results from 1 RCT, 3 controlled NRSIs and 10 noncontrolled NRSIs assessing safety of convalescent plasma. Reporting of adverse events and serious adverse events was variable. The controlled studies reported on adverse events and serious adverse events only in participants receiving convalescent plasma. The duration of followup varied. Some, but not all, studies included death as a serious adverse event. Grade 3 or 4 4 adverse events (13 studies, 201 participants) The studies did not report the grade of adverse events. Thirteen studies (201 participants) reported on adverse events of possible grade 3 or 4 4 severity. The majority of these adverse events were allergic or respiratory events. We are Auristatin F very uncertain Auristatin F whether or not convalescent plasma therapy affects the risk of moderate to severe adverse events (very lowcertainty evidence). Serious adverse events (14 studies, 5201 participants) Fourteen studies (5201 participants) reported on serious adverse events. The majority of participants were from one noncontrolled NRSI (5000 participants), which reported only on serious adverse events limited to the first four hours after convalescent plasma transfusion. This study included death as a serious adverse event; they reported 15 deaths, four of which they classified as potentially, probably or definitely related to transfusion. Other serious adverse events reported in all studies were predominantly allergic or respiratory in nature, including anaphylaxis, transfusionassociated dyspnoea, and transfusionrelated acute lung injury (TRALI). We are very uncertain whether or Auristatin F not convalescent plasma affects the number of severe adverse events. == Authors’ conclusions == We are very uncertain whether convalescent plasma is beneficial for people admitted to hospital with COVID19. For security results we also included noncontrolled NRSIs. There was limited information concerning adverse events. Of the controlled studies, none reported on this end result in the control group. There is only very lowcertainty evidence for security of convalescent plasma for COVID19. While major efforts to conduct study on COVID19 are becoming made, problems with recruiting the anticipated quantity of participants into these studies are conceivable..