• Histologic confirmation of non-muscle invasive bladder cancer of the transitional cell carcinoma high-grade subtype (mixed histology tumors allowed if transitional cell histology is predominant histology).

∙ Cohort A: Histologically confirmed CIS (with or without Ta/T1 disease); Cohort B: Histologically confirmed high-grade papillary disease (Ta/T1 only).

‣ Patients are eligible if the diagnostic biopsy was done within 3 months of treatment start and a cystoscopy demonstrating no resectable disease was done within 6 calendar weeks (inclusive of 48 days) of treatment start (residual CIS is acceptable; patients with T1 disease must undergo repeat resection if muscularis propria is not present in each biopsy sample). Patients with high-grade Ta and/or T1 disease should have complete resection before study treatment.

‣ Upper tract imaging within 6 months prior to study entry must not be suspicious for upper tract malignancy.

• Currently eligible for intravesical BCG therapy.

• Age ≥ 18 years.

• Performance status: ECOG performance status of 0, 1, or 2.

• BCG-naive disease as defined as either of the following:

∙ Have not received prior intravesical BCG; or

‣ Previously received BCG, but stopped receiving more than 3 years before date of randomization.

• Laboratory tests performed within 21 days of treatment start:

∙ Absolute lymphocyte count ≥ Institutional lower limit of normal

‣ Absolute neutrophil count (AGC/ANC) ≥ 1,000/μL

‣ Platelets ≥ 100,000/µL \[Patients may be transfused to meet this requirement\]

‣ Hemoglobin ≥ 8 g/dL \[Patients may be transfused to meet this requirement\]

‣ Calculated glomerular filtration rate (GFR\*) \>40 mL/min or Serum creatinine ≤ 1.5 x ULN

‣ Total bilirubin ≤ 2.0 X ULN

‣ AST, ALT, ALP ≤ 3.0 X ULN

• Adequate pulmonary function without any clinical sign of severe pulmonary dysfunction. PFT \> 50% FEV1 if clinically indicated by the investigator.

• Negative serum pregnancy test if female and of childbearing potential (non-childbearing is defined as greater than one year postmenopausal or surgically sterilized).

• Female participants of childbearing potential must adhere to using a medically accepted method of birth control prior to screening and agree to continue its use during the study or be surgically sterilized (e.g., hysterectomy or tubal ligation) and males must agree to use barrier methods of birth control while on study.

⁃ Provide signed informed consent and HIPPA authorization and agree to comply with all protocol-specified procedures and follow-up evaluations.

∙ using the following Cockcroft-Gault equation to calculate the eGFR for this study: eGFR in mL/min = {(140-age in years) x (weight in kg) x F}/(serum creatinine in mg/dL x 72) Where F =1 if male; and 0.85 if female