A Study of TAR-200 in Combination With Cetrelimab and Cetrelimab Alone in Participants With Muscle-Invasive Urothelial Carcinoma of the Bladder

The purpose of this study is to evaluate the anti-tumor effects of TAR-200 in combination with intravenous (IV) cetrelimab and IV cetrelimab alone.

Inclusion Criteria: * Histologically proven, cT2-T4a N0, M0 infiltrating urothelial carcinoma of the bladder. Initial diagnosis must have been within 120 days of randomization date. Participants with variant histologic subtypes are allowed if tumor(s) demonstrate urothelial predominance. However, the presence of small cell or neuroendocrine variants will make a participant ineligible * Participants with no residual tumor, or intravesical tumor size of less than or equal to (\)3 cm at screening must undergo a second debulking, re-staging TURBT. Participants will be ineligible if any individual tumor is \>3 cm after debulking TURBT * Deemed eligible for and willing to undergo RC by the operating urologist * Eastern Cooperative Oncology Group (ECOG) performance status Grade 0 or 1 * Thyroid function tests within normal range or stable on hormone supplementation per investigator assessment. Investigators may consult an endocrinologist for participant eligibility assessment in the case of equivocal or marginal tests results * All adverse events associated with any prior surgery must have resolved to common terminology criteria for adverse events (CTCAE) version 5.0 Grade less than (\