1. Non-invasive or invasive mechanical ventilation ≥ 48 hours 2. Pregnancy or breast feeding 3. Liver injury or failure (AST/ALT ≥ 5x ULN) 4. Leukocytes < 2 × 103/µl 5. Thrombocytes < 50 × 103/μl 6. Severe bacterial infection (PCT > 3ng/ml) 7. Acute or chronic diverticulitis 8. Immunosuppressive therapy (e.g. mycophenolate, azathioprine, methotrexate, biologicals, prednisolone >10mg/d, exceptions are: prednisolone ≤ 10mg/d, sulfasalazine or hydroxychloroquine) 9. Known active or chronic tuberculosis 10. Known active or chronic viral hepatitis 11. Known allergic reactions to tocilizumab or its ingredients 12. Life expectation of less than 1 year (independent of COVID-19) 13. Participation in any other interventional clinical trial within the last 30 days before the start of this trial 14. Simultaneous participation in other interventional trials (except for participation in COVID 19 trials) which could interfere with this trial, simultaneous participation in registry and diagnostic trials is allowed 15. Failure to use one of the following safe methods of contraception: female condoms, diaphragm or coil, each used in combination with spermicides, intra-uterine device, hormonal contraception in combination with a mechanical method of contraception, Women can only take part in this study if the risk of becoming pregnant is absolutely minimized. Save contraceptive methods comprise: female condoms, diaphragm or coil, each used in combination with spermicides, intra-uterine device, hormonal contraception in combination with a mechanical method of contraception and have to be used while participating in the study

1. Non-invasive or invasive mechanical ventilation ≥ 48 hours 2. Pregnancy or breast feeding 3. Liver injury or failure (AST/ALT ≥ 5x ULN) 4. Leukocytes < 2 × 103/µl 5. Thrombocytes < 50 × 103/μl 6. Severe bacterial infection (PCT > 3ng/ml) 7. Acute or chronic diverticulitis 8. Immunosuppressive therapy (e.g. mycophenolate, azathioprine, methotrexate, biologicals, prednisolone >10mg/d, exceptions are: prednisolone ≤ 10mg/d, sulfasalazine or hydroxychloroquine) 9. Known active or chronic tuberculosis 10. Known active or chronic viral hepatitis 11. Known allergic reactions to tocilizumab or its ingredients 12. Life expectation of less than 1 year (independent of COVID-19) 13. Participation in any other interventional clinical trial within the last 30 days before the start of this trial 14. Simultaneous participation in other interventional trials (except for participation in COVID 19 trials) which could interfere with this trial, simultaneous participation in registry and diagnostic trials is allowed 15. Failure to use one of the following safe methods of contraception: female condoms, diaphragm or coil, each used in combination with spermicides, intra-uterine device, hormonal contraception in combination with a mechanical method of contraception, Women can only take part in this study if the risk of becoming pregnant is absolutely minimized. Save contraceptive methods comprise: female condoms, diaphragm or coil, each used in combination with spermicides, intra-uterine device, hormonal contraception in combination with a mechanical method of contraception and have to be used while participating in the study