Preemptive Use of Convalescent Plasma for High-risk Patients With COVID-19

Inclusion Criteria:

1. Immunocompromised patients defined as
2. Solid organ transplant ≤1 year before inclusion or treated for acute or chronicrejection episode or
3. Allogeneic stem cell transplant recipients ≤2 years before inclusion or treatedfor acute GvHD ≥grade 2 or chronic moderate-severe GvHD or
4. Active solid or haematological oncological disease with curative perspectives or
5. HIV infection with CD4<350 or
6. Hypogammaglobulinemia and other severe genetic immunological defect or
7. Auto-immune disease with biological immunosuppressive treatment* or
8. Other significant immunosuppressive condition such as IgG <6, treamtent withRituximab or other biological lymphopenic treatment AND

• Age ≥ 18 years old and
• 2 distinct ABO group determination and
• Positive RT-PCR for SARS-CoV-2 on a respiratory tract sample of ≤ 7 days anddays post symptom onset (DPOS) ≤ 7 days at inclusion and/or
• No oxygen requirement (WHO 8 ordinal scale < 4): asymptomatic, mild ormoderate disease, or O2 saturation ≥ 90% at room temperature and
• Compatible ABO donor with neutralizing antibodies (NTAB) ≥1 :160 orequivalent according to predefined antibody commercial assays cut-offs (seeStudy procedures)
• RT-PCR on a respiratory tract sample with CT value<20 or ascending kineticsat the time of infusion (highly suggested but not necessary)

2. Older adults defined as Age ≥ 75 years old or ≥ 65 years old with at least oneco-existing condition

• Arterial hypertension under pharmacological treatment
• Diabetes in treatment
• Obesity (BMI ≥ 30 kg/m2)
• Chronic obstructive pulmonary disease stade GOLD ≥2
• Respiratory insufficiency due to any pneumopathy or neurologic disease.
• Cardiovascular disease as defined by either known coronary heart disease, historyof ischemic or hemorrhagic stroke or cardiac insufficiency (ejection fraction <40%)
• Chronic kidney disease (GFR<60 ml/min) AND
• 2 distinct ABO group determination and
• Positive RT-PCR for SARS-CoV-2 on a respiratory tract sample of ≤ 3 days and dayspost symptom onset (DPOS) ≤ 3 days at inclusion or RT-PCR on a respiratory tractsample with CT value<20 or ascending kinetics at the time of perfusion and
• No additional oxygen requirement compared to baseline (WHO 8 ordinal scale < 4):asymptomatic, mild or moderate disease and
• Compatible ABO donor with neutralizing antibodies (NTAB) ≥1 :160 or equivalentaccording to predefined antibody commercial assays cut-offs (see Studyprocedures)

Exclusion criteria: Seroconversion at the time of inclusion

• Palliative care
• No signed informed consent
• History of previous transfusion-related Grade 3 adverse event according to Swissmedicdefinitions
• Disseminated intravascular coagulopathy (depending on specialist evaluation)
• Uncontrolled acute hypervolemia