Study to Evaluate the Role of Siltuximab in Treatment of Cytokine Release Syndrome (CRS) and Immune Effector Cell Associated Neurotoxicity (ICANS) Related to CAR-T Cell Therapy

Inclusion Criteria: * Patients who are planned to receive chimeric antigen receptor T-cell therapy as per the United States Food and Drug Agency (USFDA) approved indications for Diffuse large B-cell lymphoma (DLBCL), Mantle cell lymphoma (MCL), Follicular lymphoma (FL), Primary mediastinal large B-cell lymphoma (PMBCL), High grade B-cell lymphoma, DLBCL arising from follicular lymphoma, Multiple myeloma and B-cell precursor acute lymphoblastic leukemia * Patients with hepatitis C virus (HCV) can be included if they have completed therapy for hepatitis C with undetectable HCV RNA viral load. * Patients with Hepatitis B can be included if they are on suppressive therapy for hepatitis B infection and with no detectable viral load. * Adequate organ function as defined below unless attributed to disease involvement.Acceptable window for assessing adequate organ function is 7 days to 30 days before planned CAR T-cell infusion with day 0 as the planned day of CAR T-cell infusion.Adequate liver function (bilirubin \< 2mg/dL, aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) \<3 x ULN), adequate kidney function (crcl \> 30ml/min using Cockcroft-Gault, based on actual weight) and adequate hematological parameters (Absolute neutrophil count ≥ 1,000/µL, Hemoglobin \> 8, Platelet Count ≥ 50,000/ µL) * Patients able to tolerate washout periods for therapies prior to CAR T-cell infusion. Systemic therapy: Washout period is 2 weeks prior to CAR T-cell infusion. Radiatio…