Perioperative Enfortumab Vedotin (EV) Plus Pembrolizumab (MK-3475) Versus Neoadjuvant Chemotherapy for Cisplatin-Eligible Muscle Invasive Bladder Cancer (MIBC) (MK-3475-B15/ KEYNOTE-B15 / EV-304)

EFS is defined as the time from randomization to the first occurrence of following events: radiographic disease progression precluding RC + PLND, failure to undergo surgery in participants with residual disease, gross residual disease left behind at time of surgery, local or distant recurrence based on blinded independent central review (BICR) or death due to any cause.

pCR rate is defined as defined as the proportion of participants having pCR. pCR is defined as absence of viable tumor (pT0N0) in examined tissue from radical cystectomy (RC) + pelvic lymph node dissection (PLND), as assessed by blinded central pathologic review.

OS is defined as the time from randomization to death due to any cause.

DFS is defined as the time from postsurgery baseline scan until the first occurrence of either local/distant recurrence as assessed by BICR imaging and/or biopsy or death from any cause.

pDS is defined as participants with <pT2 (includes pT0, pTis, pTa, and pT1) and N0 in examined tissue from RC plus PLND, based on central pathologic review.

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. The number of participants who experience an AE will be presented.

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. The number of participants who discontinue study treatment due to an AE will be presented.

Perioperative complications are defined as both intraoperative and postoperative complications, potentially contributing to increased length of inpatient care and/or delay of adjuvant therapy. The number of participants experiencing perioperative complications will be presented.

The EORTC QLQ-C30 is a 30-item questionnaire to assess the overall quality of life in cancer participants. Participant responses to questions 29 ("How would you rate your overall health during the past week?") and 30 ("How would you rate your overall quality of life during the past week?") are scored on a 7-point scale (1= Very poor to 7=Excellent). A higher score indicates a better overall health/quality of life status. The change from baseline in EORTC QLQ-C30 Items 29 and 30 combined scores will be presented.

The EORTC QLQ-C30 is a 30-item questionnaire to assess the overall quality of life of cancer patients. Participant responses to 5 questions about their physical functioning are scored on a 4-point scale (1=not at all to 4=very much). A higher score indicates a better quality of life. The change from baseline in physical function (EORTC QLQ-C30 Items 1-5) score will be presented.

The BCI is a 36-item validated, condition-specific health questionnaire to assess the quality of life among participants with bladder cancer. The BCI contains 3 domains: urinary (14 items), bowel (10 items), and sexual (12 items) with function (Likert response scale: 0 [Never] - 4 [Always]) and bother (Likert response scale: 0 [No problem] - 4 [Big problem]) subdomains. The domain and subdomain scores are standardized to a 0 to 100 point scale where higher scores correspond better functioning and health-related qualify of life. The change from baseline in the combined scores of the urinary, bowel, and sexual domains of the BCI will be presented.

The EQ-5D-5L VAS records the respondent's self-rated health on a 10 centimeter (cm) vertical, visual analogue scale. It is rated by the respondent on a scale 0 to 100, with 0 being "the worst health you can imagine" and 100 being "the best health you can imagine". The change from baseline in EQ-5D-5L VAS will be presented.

The EORTC QLQ-C30 is a 30-item questionnaire to assess the overall quality of life of cancer patients. Participant responses to the questions "Were you limited in doing either your work or other daily activities during the past week?" and " Were you limited in pursuing your hobbies or other leisure time activities during the past week?" will be scored on a 4-point scale (1=Not at All to 4=Very Much). Higher scores indicate a better level of role functioning. Change from baseline in the role functioning (EORTC QLQ-C30 Items 6-7) combined score will be presented.