•The option for retreatment was removed from the protocol. Revised Protocol 0203-Apr-2018•This protocol has been revised to modify the combination escalation of BMS-986226 with either nivolumab (Part B) or ipilimumab (Part C) to include and prioritize a Q12W dosing schedule. •On-treatment biopsy collections were changed to Q2W and Q12W. •A tetanus booster will be administered to capture pharmacodynamic activity in an antigen-specific context. •Treatment duration of BMS-986226 in combination with nivolumab or ipilimumab will be 2 years. Revised Protocol 0120-Jul-2017 Preliminary safety cohort added Original Protocol 26-May-2017 Not Applicable Approved 5.0 v Approved 1.0 v Clinical Protocol CA021002 BMS-986226 anti-ICOS OVERALL RATIONALE FOR REVISED PROTOCOL 04: This protocol has been revised to include recommended premedication for all participants receiving BMS-986226 treatment. In addition, fa sting glucose assessment was limited to Screening, while on-treatment glucose testing may be non-fasting. SUMMARY OF KEY CHANGES FOR REVISED PROTOCOL 04 Section Number & Title Description of Change Brief Rationale Table 2-1 Screening Procedural Outline (CA021002); Table 2-2 On-treatment Procedural Outline (CA021002); Table 9.4.4-1 Clinical Laboratory TestsFasting glucose testing was limited to Screening. On-treatment glucose testing may be non-fastingTo clarify that fasting glucose assessment is not required for subjects while on treatment. Synopsis; Table 2-2 On-treatment Procedural Outline (CA021002); Section 3.3 Benefit/Risk Assessment; Section 5.1.2.1 Monotherapy Dose Escalation (Preliminary Safety Cohorts and Part A);Section 5.1.2.2 BMS-986226 and Nivolumab Combination Therapy Cohort (Parts B1 and B2); Section 5.1.2.3 BMS-986226 and Ipilimumab Combination Therapy Cohort (Parts C1 and C2); Section 5.1.2.4 Combination Expansion Arms (Parts D and E); Section 7.1 Treatments AdministeredParticipants are recommended to receive premedication with diphenhydramine and acetaminophen to reduce risk of infusion-related reactions.Premedication recommendation was instituted in order to reduce the risk of infusion-related reactions associated with BMS-986226 treatment. Section 3.2.2.4 Clinical Pharmacology and SafetyUpdated safety data.Updated to provide most recent data.