Inclusion Criteria:  Confirmed diagnosis of SARS-CoV-2 (using virus ribonucleic acid polymerase chain reaction (RNA PCR) test during in-hospital therapy or within 5 days prior to hospital admission). Hospital admission for COVID-19 therapy. Pulmonary changes typical for SARS-CoV-2 infection based on imaging findings (chest X-ray, chest computed tomography (CT)).  Indications for Preemptive anti-inflammatory therapy (PAT), including two or more signs below:  reduced oxygen saturation of the blood SpO2 ≤ 97 % C-reactive protein (CRP) > 15 mg/L body temperature > 37.5 °C for at least 3 days white blood cell count < 4.0 x 10^9/L absolute lymphocyte count < 2.0 x 10^9/L. Olokizumab therapy - for the test group. Source medical documents contain the information required for the study (lacking or incomplete data on some serum chemistry values are allowed: D-dimer, ferritin, IL-6, procalcitonin).  Exclusion Criteria:  Inadequate information on patient's characteristics and therapy. Lack of documented confirmation of SARS-CoV-2 infection. Initiation of mechanical ventilation (MV) from the first day of admission in the control group or before olokizumab administration in the test group. Administration of systemic corticosteroids, IL-6, other immunosuppressants or immunoglobulins before hospital admission. Administration of olokizumab, other interleukin (IL) (interleukin-1 and interleukin-17) inhibitors and Janus-kinase inhibitors - for comparator group.