Pei 2020.

Study characteristics
Methods	Trial design: case series Type of publication: preprint, supplementary material missing Setting: NR Recruitment dates: NR Country: China Language: English Number of centres: 1 Trial registration number: NR Date of registration: NR
Participants	(Preprint only, participant characteristics will be described in the supplementary material; not accessible yet) Age: NR Gender: NR Ethnicity: NR Number of participants (recruited/allocated/evaluated): 3 Severity of disease: moderate to critical Co‐morbidities: NR Inclusion criteria: severely and critically ill COVID‐19 patients, and patients suffering advanced stages of the disease. Duration of the disease is within 3 weeks, novel coronavirus virus nucleic acid test is positive with viraemia. Severely and critically ill COVID‐19 patients assessed by clinicians. Patients with long‐term (> 4 weeks) positive novel coronavirus nucleic acid test Exclusion criteria: congenital IgA deficiency. A history of allergy including plasma infusion, human plasma protein products, sodium citrate. Plasma inactivated by methylene blue virus is strictly prohibited in patients with methylene blue allergy. Other history of severe allergies and contraindications. At the end of critical illness with irreversible multiple organ failure. Other conditions that are not suitable for infusion assessed by clinicians Previous treatments (e.g. experimental drug therapies, oxygen therapy, ventilation): NR
Interventions	CP therapy or hyperimmune immunoglobulin therapy: CP therapy Details of CP Type of plasma: apheresis plasma. Fully automatic apheresis machine or a fully automatic blood cell separator (refer to technical operation procedures of blood station). Volume: 200‐400 mL (the exact volume should be assessed by clinicians). The interval between plasma collection should be > 2 weeks. Storage: it is made available under a CC‐BY‐NC 4.0 International license. Follow the principle of sterility, repackaging the plasma 100‐200 mL each. Store at 2‐6 °C for 48 h. For long‐term storage, it should be rapidly frozen to −20 °C. Packaging: labelling requirements ‐ refer to technical operation procedures of blood station Volume: according to the clinical status and the participant’s weight. Usually the infusion dose is 200‐500 mL (4‐5 mL/kg) Number of doses: according to the clinical status and the participant’s weight. Usually the infusion dose is 200‐500 mL (4‐5 mL/kg) Antibody test and antibody‐titre: ELISA, colloidal gold label technology, chemiluminescence; > 1:160 Pathogen inactivated or not: NR RT‐PCR tested: negative novel coronavirus nucleic acid test Details of donors Gender: both HLA and HNA antibody‐negative: excluded: with a history of pregnancy or transfusion whose HNA antibody and HLA antibody are positive Severity of disease: NR Timing from recovery from disease: > 3 weeks after the onset of symptoms of COVID‐19 and complete resolution of symptoms at least 14 days prior to donation RT‐PCR tested: NR Treatment details, including time of plasma therapy (e.g. early stage of disease): administered between 12 and 27 days after admission For studies including a control group: comparator (type): not applicable Concomitant therapy: NR Duration of follow‐up: up to 36 days Treatment cross‐overs: not applicable Compliance with assigned treatment: moderate (2/3 compliant, 1 participant received 30 mL of CP and experienced an AE)
Outcomes	Primary study outcome: NR Primary review outcomes All‐cause mortality at hospital discharge: reported Time to death: not applicable Secondary review outcomes Number of participants with grade 3 and grade 4 AEs, including potential relationship between intervention and adverse reaction (e.g. TRALI, transfusion‐transmitted infection, TACO, TAD, acute transfusion reactions): NR Number of participants with SAEs: reported Improvement of clinical symptoms, assessed through need for respiratory support at up to 7 days; 8‐15 days; 16‐30 days: NR 30‐day and 90‐day mortality: not applicable Admission on the ICU: NR Length of stay on the ICU: NR Time to discharge from hospital: reported QoL: NR Additional study outcomes: SARS‐CoV‐2 nucleic acid test
Notes	Sponsor/funding: no funding received COIs: all study authors declare no competing interests Other: "the participants gave their written informed consent and approved by the hospital ethics committee. All relevant ethical guidelines have been followed; any necessary IRB and/or ethics committee approvals have been obtained and details of the IRB/oversight body are included in the manuscript. Yes. All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes. I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE‐approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes. I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes"