Patients will be screened and enrolled prior to undergoing standard of care TURBT for known or suspected Stage Ta, T1 or Tis bladder cancer of any histological grade requiring TURBT and who are believed to be candidates for IPOP intravesical chemotherapy regardless of the need for further intravesical therapy. Within 6 hours after completion of TURBT, patients will be administered a single IPOP intravesical instillation of Chemophase with a one-hour dwell time. At the end of the one-hour dwell time, the patient will be asked to fully void or, if an intravesical catheter has been left in place, the bladder will be fully drained via the catheter. Patients will return at 1 and 2 weeks post instillation for follow up visits for safety and for a cystoscopy at day 85 (per standard of care). Safety and tolerability will be assessed through physical examinations, vital signs, cystoscopy, hematology (CBC), adverse event reporting, and measurements of plasma levels of MMC.