* concurrent use of invasive mechanical ventilation * concurrent use of vasopressor or inotropic medications * previous receipt of tocilizumab or another anti-il6r or il-6 inhibitor in the year prior. * known history of hypersensitivity to tocilizumab. * diagnosis of end-stage liver disease or listed for liver transplant. * elevation of ast or alt in excess of 10 times the upper limit of normal. * neutropenia (absolute neutrophil count \< 500/ul). * thrombocytopenia (platelets \< 50,000/ul). * on active therapy with a bruton's tyrosine kinase-targeted agent, which include the following: * acalabrutinib * ibrutinib * zanubrutinib * on active therapy with a jak2-targeted agent, which include the following: * tofacitinib * baricitinib * upadacitinib * ruxolitinib * any of the following biologic immunosuppressive agent (and any biosimilar versions thereof) administered in the past 6 months or less:: * abatacept * adalimumab * alemtuzumab * atezolizumab * belimumab * blinatumomab * brentuximab * certolizumab * daratumumab * durvalumab * eculizumab * elotuzumab * etanercept * gemtuzumab * golimumab * ibritumomab * infliximab * inotuzumab * ipilimumab * ixekizumab * moxetumomab * nivolumab * obinutuzumab * ocrelizumab * ofatumumab * pembrolizumab * polatuzumab * rituximab * rituximab * sarilumab * secukinumab * tocilizumab * tositumumab * tremelimumab * urelumab * ustekinumab * history of bone marrow transplantation (including chimeric antigen receptor t-cell) or solid organ transplant * known history of hepatitis b or hepatitis c (patients who have completed curative-intent anti-hcv treatments are not excluded from trial) * positive result on hepatitis b or c screening * known history of mycobacterium tuberculosis infection at risk for reactivation * known history of gastrointestinal perforation * active diverticulitis * multi-organ failure as determined by primary treating physicians * any other documented serious, active infection besides covid-19 - including but not limited to: lobar pneumonia consistent with bacterial infection, bacteremia, culture-negative endocarditis, or current mycobacterial infection - at the discretion of primary treating physicians * pregnant patients or nursing mothers * patients who are unable to discontinue scheduled antipyretic medications, either as monotherapy (e.g., acetaminophen or ibuprofen \[aspirin is acceptable\]) or as part of combination therapy (e.g., hydrocodone/acetaminophen, aspirin/acetaminophen/caffeine \[excedrin®\]) * crp \< 40 mg/l

* concurrent use of invasive mechanical ventilation * concurrent use of vasopressor or inotropic medications * previous receipt of tocilizumab or another anti-il6r or il-6 inhibitor in the year prior. * known history of hypersensitivity to tocilizumab. * diagnosis of end-stage liver disease or listed for liver transplant. * elevation of ast or alt in excess of 10 times the upper limit of normal. * neutropenia (absolute neutrophil count \< 500/ul). * thrombocytopenia (platelets \< 50,000/ul). * on active therapy with a bruton's tyrosine kinase-targeted agent, which include the following: * acalabrutinib * ibrutinib * zanubrutinib * on active therapy with a jak2-targeted agent, which include the following: * tofacitinib * baricitinib * upadacitinib * ruxolitinib * any of the following biologic immunosuppressive agent (and any biosimilar versions thereof) administered in the past 6 months or less:: * abatacept * adalimumab * alemtuzumab * atezolizumab * belimumab * blinatumomab * brentuximab * certolizumab * daratumumab * durvalumab * eculizumab * elotuzumab * etanercept * gemtuzumab * golimumab * ibritumomab * infliximab * inotuzumab * ipilimumab * ixekizumab * moxetumomab * nivolumab * obinutuzumab * ocrelizumab * ofatumumab * pembrolizumab * polatuzumab * rituximab * rituximab * sarilumab * secukinumab * tocilizumab * tositumumab * tremelimumab * urelumab * ustekinumab * history of bone marrow transplantation (including chimeric antigen receptor t-cell) or solid organ transplant * known history of hepatitis b or hepatitis c (patients who have completed curative-intent anti-hcv treatments are not excluded from trial) * positive result on hepatitis b or c screening * known history of mycobacterium tuberculosis infection at risk for reactivation * known history of gastrointestinal perforation * active diverticulitis * multi-organ failure as determined by primary treating physicians * any other documented serious, active infection besides covid-19 - including but not limited to: lobar pneumonia consistent with bacterial infection, bacteremia, culture-negative endocarditis, or current mycobacterial infection - at the discretion of primary treating physicians * pregnant patients or nursing mothers * patients who are unable to discontinue scheduled antipyretic medications, either as monotherapy (e.g., acetaminophen or ibuprofen \[aspirin is acceptable\]) or as part of combination therapy (e.g., hydrocodone/acetaminophen, aspirin/acetaminophen/caffeine \[excedrin®\]) * crp \< 40 mg/l

- concurrent use of invasive mechanical ventilation - concurrent use of vasopressor or inotropic medications - previous receipt of tocilizumab or another anti-il6r or il-6 inhibitor in the year prior. - known history of hypersensitivity to tocilizumab. - diagnosis of end-stage liver disease or listed for liver transplant. - elevation of ast or alt in excess of 10 times the upper limit of normal. - neutropenia (absolute neutrophil count < 500/ul). - thrombocytopenia (platelets < 50,000/ul). - on active therapy with a bruton's tyrosine kinase-targeted agent, which include the following: - acalabrutinib - ibrutinib - zanubrutinib - on active therapy with a jak2-targeted agent, which include the following: - tofacitinib - baricitinib - upadacitinib - ruxolitinib - any of the following biologic immunosuppressive agent (and any biosimilar versions thereof) administered in the past 6 months or less:: - abatacept - adalimumab - alemtuzumab - atezolizumab - belimumab - blinatumomab - brentuximab - certolizumab - daratumumab - durvalumab - eculizumab - elotuzumab - etanercept - gemtuzumab - golimumab - ibritumomab - infliximab - inotuzumab - ipilimumab - ixekizumab - moxetumomab - nivolumab - obinutuzumab - ocrelizumab - ofatumumab - pembrolizumab - polatuzumab - rituximab - rituximab - sarilumab - secukinumab - tocilizumab - tositumumab - tremelimumab - urelumab - ustekinumab - history of bone marrow transplantation (including chimeric antigen receptor t-cell) or solid organ transplant - known history of hepatitis b or hepatitis c (patients who have completed curative-intent anti-hcv treatments are not excluded from trial) - positive result on hepatitis b or c screening - known history of mycobacterium tuberculosis infection at risk for reactivation - known history of gastrointestinal perforation - active diverticulitis - multi-organ failure as determined by primary treating physicians - any other documented serious, active infection besides covid-19 - including but not limited to: lobar pneumonia consistent with bacterial infection, bacteremia, culture-negative endocarditis, or current mycobacterial infection - at the discretion of primary treating physicians - pregnant patients or nursing mothers - patients who are unable to discontinue scheduled antipyretic medications, either as monotherapy (e.g., acetaminophen or ibuprofen [aspirin is acceptable]) or as part of combination therapy (e.g., hydrocodone/acetaminophen, aspirin/acetaminophen/caffeine [excedrin®]) - crp < 40 mg/l

- concurrent use of invasive mechanical ventilation - concurrent use of vasopressor or inotropic medications - previous receipt of tocilizumab or another anti-il6r or il-6 inhibitor in the year prior. - known history of hypersensitivity to tocilizumab. - diagnosis of end-stage liver disease or listed for liver transplant. - elevation of ast or alt in excess of 10 times the upper limit of normal. - neutropenia (absolute neutrophil count < 500/ul). - thrombocytopenia (platelets < 50,000/ul). - on active therapy with a bruton's tyrosine kinase-targeted agent, which include the following: - acalabrutinib - ibrutinib - zanubrutinib - on active therapy with a jak2-targeted agent, which include the following: - tofacitinib - baricitinib - upadacitinib - ruxolitinib - any of the following biologic immunosuppressive agent (and any biosimilar versions thereof) administered in the past 6 months or less:: - abatacept - adalimumab - alemtuzumab - atezolizumab - belimumab - blinatumomab - brentuximab - certolizumab - daratumumab - durvalumab - eculizumab - elotuzumab - etanercept - gemtuzumab - golimumab - ibritumomab - infliximab - inotuzumab - ipilimumab - ixekizumab - moxetumomab - nivolumab - obinutuzumab - ocrelizumab - ofatumumab - pembrolizumab - polatuzumab - rituximab - rituximab - sarilumab - secukinumab - tocilizumab - tositumumab - tremelimumab - urelumab - ustekinumab - history of bone marrow transplantation (including chimeric antigen receptor t-cell) or solid organ transplant - known history of hepatitis b or hepatitis c (patients who have completed curative-intent anti-hcv treatments are not excluded from trial) - positive result on hepatitis b or c screening - known history of mycobacterium tuberculosis infection at risk for reactivation - known history of gastrointestinal perforation - active diverticulitis - multi-organ failure as determined by primary treating physicians - any other documented serious, active infection besides covid-19 - including but not limited to: lobar pneumonia consistent with bacterial infection, bacteremia, culture-negative endocarditis, or current mycobacterial infection - at the discretion of primary treating physicians - pregnant patients or nursing mothers - patients who are unable to discontinue scheduled antipyretic medications, either as monotherapy (e.g., acetaminophen or ibuprofen [aspirin is acceptable]) or as part of combination therapy (e.g., hydrocodone/acetaminophen, aspirin/acetaminophen/caffeine [excedrin®]) - crp < 40 mg/l