A maximum of 18 patients with histologically confirmed H19 positive superficial bladder cancer with multiple or recurrent stage Ta tumors or CIS will be included in this study. Patients with any grade 3, or any stage T1 or higher stage, will be excluded. This is a multicenter, dose escalation study in which, after eligibility criteria have been met, patients in five groups of 3 patients each, will receive escalating doses of DTA-H19 intravesically over a seven-week period. Treatments will be given weekly for three weeks followed one week later by safety and disease assessments, then another 3 weekly instillations will be performed. Each dose cohort will receive the same dose for all treatments. The first dose cohort will receive 2 mg of DTA-H19 plasmid per intravesical treatment for all treatments. The next dose cohort of 3 patients will receive 4 mg, the next 6 mg, the next 12 mg,and then the final dose cohort will receive 20 mg of DTA-H19 plasmid DNA. All doses will be mixed with polyethylenimine (PEI) to improve transduction efficiency. Doses will be escalated if none of the first three patients in the preceding dose cohort experience a dose limiting toxicity (DLT) after the first three weekly intravesical treatments.