The National Institute of Health COVID-19 Treatment Guidelines states that there are insufficient data to recommend either for or against the use of convalescent plasma for the treatment of COVID-19. Convalescent plasma should not be considered the standard of care for the treatment of patients
with COVID-19. Prospective, well-controlled, adequately powered randomized trials are needed to determine whether convalescent plasma is effective and safe for the treatment of COVID-19. 
The Food and Drug Administration issued an Emergency Use Authorization (EUA) for COVID-19
convalescent plasma for the treatment of hospitalized patients with COVID-19. 
The Infectious Diseases Society of America (IDSA) COVID-19 Guidelines state that among patients who have been admitted to the hospital with COVID-19, convalescent plasma should be used only in the context of a clinical trial. 
A review article stated that human plasma from recovered COVID-19 patients is projected to be a safe and potentially effective therapy for treatment and post-exposure prophylaxis. Substantial evidence of benefit with prior use for viral infections offers strong precedent for such an approach. However, well-controlled clinical trials need to be performed to confirm efficacy. 
A review article assessed that the number of COVID-19 patients with known outcomes of convalescent plasma administration is limited, stemming from 6 case series. The follow-up of cases reaching hospitalizations of 51 days and 60 days after onset of symptoms highlights the need for adequate observation, but also underlines the time needed from the early, sizable Chinese cohorts to provide robust results in relevant scientific publications. The formulation, namely convalescent plasma or hyperimmune globulin, as well as the optimal time frame, remain to be identified in the future. 
A review article states that convalescent plasma from donors who have recovered from COVID-19 may be most promising when used as prophylaxis or when administered shortly after symptom onset (within 14 days). Given the lack of information around the natural history of this COVID-19 virus, pathogen reduction technology (PRT) should be considered to add a layer of safety to protect recipients of convalescent plasma.
A review of articles published in PubMed was performed in July 2020 to summarize the currently available evidence in human studies for convalescent plasma as a treatment for coronaviruses. The review included sixteen COVID-19, four Middle East respiratory syndrome (MERS), and five Severe acute respiratory syndrome (SARS) reports describing convalescent plasma use in humans. There were two randomized control trials, both of which were for COVID-19 and were terminated early. Most COVID-19 reports described a potential benefit of convalescent plasma on clinical outcomes in severe or critically ill patients with few immediate adverse events. However, there were a number of limitations, including the concurrent use of antivirals, steroids and other treatments, small sample sizes, lack of randomization or control groups, and short follow-up time. 
A meta-analyses and systematic review of convalescent plasma in COVID-19 and other severe respiratory viral infections was performed. Included were studies of patients infected with SARS-CoV-2, SARS-CoV, MERS-CoV or influenza virus with severe respiratory infection, and Ebola virus infection. However, no eligible studies of COVID-19 were identified. The authors concluded that studies of non-COVID-19 severe respiratory viral infections provide indirect, very low-quality evidence that raises the possibility that convalescent plasma has minimal or no benefit in the treatment of COVID-19 and low-quality evidence that it does not cause serious adverse events. 
An on-going/living systematic review included studies evaluating convalescent plasma or hyperimmune immunoglobulin for people with COVID-19, irrespective of study design, disease severity, age, gender or ethnicity. While still being updated, it is currently uncertain whether convalescent plasma is beneficial for people admitted to hospital with COVID-19. Additionally, there is low-certainty evidence for safety of convalescent plasma for COVID-19.