Inclusion Criteria:  SARS-CoV-2 infection proven by PCR. Positive detection of anti-interferon antibodies. Patient, family or deferred consent (emergency clause). Affiliation to a social security scheme (or exemption from affiliation). Inclusions are possible also for protected patient (under guardianship and tutornship).  Exclusion Criteria:  Pregnant women, parturients and nursing mothers Minor patient Participation in another interventional trial in progress, with the objective, even secondary, of reducing mortality Indication to EPT for another associated pathology Contra-indication to EPT, known allergy to albumin 5%. Persons under court protection, Disturbance of the haemostasis balance (PT<50%, APTT>1.5 and fibrinogen <1g/L) Patient presenting a hemorrhagic diathesis (intracranial or digestive bleeding or threatening the functional prognosis) Any progressive and advanced pathology whose life expectancy is less than one month Bacterial or viral infectious disease (HIV) explaining most of the aggravation