A Clinical Study of Sacituzumab Tirumotecan (MK-2870) in Patients With Bladder Cancer (MK-2870-027)

The goal of the study is to learn about the safety of Sacituzumab Tirumotecan and if people can tolerate it when given in the bladder and find the highest dose that people can take without having certain problems. Researchers will then choose a dose level of Sacituzumab Tirumotecan to use in future studies to learn how well the drug works.

Inclusion Criteria: The key inclusion criteria include but are not limited to the following: * Has recurrent low-grade (Ta) Non-Muscle Invasive Bladder Cancer (NMIBC) in the bladder * Must have visible tumor by cystoscopy within 12 weeks prior to first dose * Has intermediate-risk NMIBC defined as 1 or more of the following risk factors: * Multiple tumors * \>1 occurrence of low-grade NMIBC within 1 year of the current diagnosis at Screening * Early recurrence (\3 cm * Failure of prior intravesical treatment * An Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2 assessed within 14 days prior to first dose Exclusion Criteria: The key exclusion criteria include but are not limited to the following: * Newly diagnosed low-grade non-muscle invasive bladder cancer (Ta NMIBC) in the bladder * Past or current history of high-grade (Ta or T1 or CIS) NMIBC, muscle invasive bladder cancer (MIBC) or metastatic urothelial carcinoma (UC) * Has a condition that would prohibit normal voiding (or hold bladder voiding for 1 to 2 hours) * Has history of documented severe dry eye syndrome, severe Meibomian gland disease, and/or blepharitis, or severe corneal disease that prevents and/or delays corneal healing * Has active inflammatory bowel disease requiring immunosuppressive medication or previous history of inflammatory bowel disease (eg, Chron's disease, ulcerative colitis, or chronic diarrhea) * Has uncontrolled, significant cardiovascular disease or cerebrovascular disease * Known additional malignancy that is progressing or has required active treatment within the past 3 years * History of (noninfectious) pneumonitis/interstitial lung disease that required steroids or has current pneumonitis/interstitial lung disease.