The stability and antitumor activity of recycled (intravesical) mitomycin C

Although intravesical mitomycin C (MMC) is effective in the treatment of superficial bladder cancer, its expense is a major factor limiting its use. These authors have analyzed the antitumor activity and stability of MMC following 2-hour intravesical instillation in consideration of recycling the drug or using a smaller dose over a longer retention time. The first voided urine samples from 11 patients who received 40 mg MMC intravesically were measured for MMC content by high performance liquid chromatography (HPLC). An average of 50% of the parent drug was recovered. MMC from the urine samples inhibited the growth of a transplantable murine transitional cell carcinoma as effectively as stock drug. Moreover, MMC is relatively stable in human urine at body temperature. These findings suggest that recovery and reuse of the intravesically administered drug is possible and if sterility and appropriate concentrations can be established for the initial and subsequent doses, the drug may be able to be recycled.