MMC will be administered intravesically.

Gemcitabine will be administered intravesically.

TTDW is measured as the time from randomization to the date of cystectomy, systemic therapy, or radiation therapy, whichever occurs first.

TTP is measured as the time from randomization to the date of first documented evidence of disease progression (i.e., progression to muscle-invasive bladder cancer [MIBC] [T greater than or equal to {>=} 2], lymph node [N+], or distant disease [M+]), or death due to disease progression, whichever occurs first.

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

Number of participants with AEs by severity grade as assessed by CTCAE version 5.0 will be reported. Grade refers to the severity of AE as follows: Grade 1- Mild; Grade 2- Moderate; Grade 3- Severe; Grade 4- Life-threatening; Grade 5- Death related to adverse event.

Number of participants with change from baseline in laboratory abnormalities (hematology, serum chemistry and urine analysis) will be reported.

Number of participants with change from baseline in vital signs (temperature, pulse/heart rate, respiratory rate and blood pressure) will be reported.

EORTC QLQ-C30 is a 30-item questionnaire for evaluating the health-related quality of life (HRQoL) of participants participating in cancer clinical studies. It includes 5 functional scales (physical, role, cognitive, emotional, and social), 3 symptom scales (fatigue, pain, and nausea or vomiting), a global health status or HRQoL scale and 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties). Ratings for each item range from 1 (not at all) to 4 (very much). Higher scores indicate greater functioning, better global health status, or more severe symptoms.

EORTC QLQ-NMIBC24 is a 24-item questionnaire for evaluating the HRQoL of participants with NMIBC. The questionnaire is designed to supplement the QLQ-C30 and incorporates 6 multi-item scales (urinary symptoms, malaise, future worries, bloating and flatulence, sexual function and male sexual problems) and 5 single items (intravesical treatment issues, sexual intimacy, worries about risk of contaminating partner, sexual enjoyment, and female sexual problems). Ratings for each item range from 1 (not at all) to 4 (very much). Higher scores represent a high level of symptoms or problems, except for sexual function and sexual enjoyment, where a higher score represents a higher level of functioning.

EORTC QLQ-C30 is a 30-item questionnaire for evaluating the health-related quality of life (HRQoL) of participants participating in cancer clinical studies. It includes 5 functional scales (physical, role, cognitive, emotional, and social), 3 symptom scales (fatigue, pain, and nausea or vomiting), a global health status or HRQoL scale and 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties). Ratings for each item range from 1 (not at all) to 4 (very much). Higher scores indicate greater functioning, better global health status, or more severe symptoms.

EORTC QLQ-NMIBC24 is a 24-item questionnaire for evaluating the HRQoL of participants with NMIBC. The questionnaire is designed to supplement the QLQ-C30 and incorporates 6 multi-item scales (urinary symptoms, malaise, future worries, bloating and flatulence, sexual function and male sexual problems) and 5 single items (intravesical treatment issues, sexual intimacy, worries about risk of contaminating partner, sexual enjoyment, and female sexual problems). Ratings for each item range from 1 (not at all) to 4 (very much). Higher scores represent a high level of symptoms or problems, except for sexual function and sexual enjoyment, where a higher score represents a higher level of functioning.

EORTC Q168 is a single item from the EORTC item library used to measure the overall impact of treatment side effects. Responses are rated on a 4-point Likert response scale ranging from 1 "Not at all" to 4 "Very much." Higher score indicates greater impact.