•Protocol waivers or exemptions are not allowed. •All immediate safety concerns must be discussed with the Spons or immediately upon occurrence or awareness to determine if the participant should continue or discontinue treatment. •Adherence to the study design requirements, including those specified in the Schedule of Activities (Section 2), is essential and required for study conduct. •All screening evaluations must be completed and reviewed to confirm that potential participants meet all eligibility criteria be fore randomization. The investigator will maintain a screening log to record details of all participants screened and to confirm eligibility or record reasons for screening failure, as applicable. •Procedures conducted as part of the participant’s routine clinical management (eg, blood count) and obtained before signing of informed consent may be utilized for screening or baseline purposes provided the procedure meets the protocol-defined criteria and has been performed within the timeframe defined in the Schedule of Activities (Section 2). Additional measures, including non-study-required laboratory tests, should be performed as clinically indicated or to comply with local regulations. Laboratory toxicities (eg, suspected drug-induced liver enzyme evaluations) will be monitore d during the follow-up phase via on-site/local laboratories until all study treatment-r elated toxi cities resolve, ret urn to baseline, or are deemed irreversible. If a participant shows pulmonary-related signs (hypoxia or fever) or symptoms (eg, dyspnea, cough, or fever) consistent with possible pulmonary AEs, the participant should be immediately Revised Protocol No.: 04 Date: 31-May-2019 98 Approved 5.0 v Approved 1.0 v Clinical Protocol CA021002 BMS-986226 anti-ICOS evaluated to rule out pulmonary tox icity according to the suspected pulmonary toxicity management algorithm in the ipilimumab IB.18 Some of the assessments referred to in this section may not be captured as data in the CRF. They are intended to be used as safety monitoring by the treating physician.