Inclusion Criteria:  Age equal to or above 18 years. Both genders. In case of women, unwillingness to become pregnant during the study period. Written informed consent provided by the patient or by one first-degree relative/spouse in case of patients unable to consent. Community-acquired pneumonia (CAP) or hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) or primary bacteremia (BSI). Sepsis defined by the Sepsis-3 definitions. More precisely, sepsis is defined as the presence of total SOFA (sequential organ failure assessment score) equal to 2 or more for patients who are admitted with infection at the emergency department OR as any increase of admission SOFA by 2 or more points for patients already hospitalized. Patients with signs of fulminant hyper-inflammation or sepsis-associated immunoparalysis as defined by ferritin and Quantibrite. Since the state of hyper-inflammation is considered more life-threatening than the state of immunoparalysis, patients with lab findings of both immune states are allocated to treatment targeting hyper-inflammation. It is explicitly stated that patients diagnosed with novel Coronavirus-2 infection (COVID-19) may participate only in the fulminant hyper-inflammation arm Time from classification into sepsis by the Sepsis-3 definitions and start of blind intervention less than 72 hours.  Exclusion Criteria:  Age below 18 years. Denial for written informed consent. Acute pyelonephritis or intraabdominal infection, meningitis or skin infection. Any stage IV malignancy. Neutropenia defined as an absolute neutrophil count lower than 1,500/mm3. Any 'do not resuscitate' decision in the hospital. In the case of BSI, patients with blood cultures growing coagulase-negative staphylococci or skin commensals or catheter-related infections cannot be enrolled. Active tuberculosis (TB) as defined by the co-administration of drugs for the treatment of TB. Infection by the human immunodeficiency virus (HIV). Any primary immunodeficiency. Oral or intravenous intake of corticosteroids at a daily dose equal or greater than 0.4 mg/kg prednisone or greater the last 15 days. Any anti-cytokine biological treatment the last one month. Medical history of systemic lupus erythematosus. Medical history of multiple sclerosis or any other demyelinating disorder. Pregnancy or lactation. Women of child-bearing potential will be screened by a urine pregnancy test before inclusion in the study.