The main purpose of this research study is to evaluate the safety and dosing of CG0070.

Cohorts of three to six patients will be assigned to receive intravesical (into the bladder) administration of CG0070 either Weekly or Every 4 Weeks for up to a total of 6 doses.

Inclusion Criteria:

• High grade non-muscle invasive bladder cancer (stages Ta, T1 and/or CIS - carcinoma in situ). High grade being defined as G2 or G3 disease.
• Failure of at least one prior treatment with BCG, defined as evidence of TCC on cystoscopic exam and biopsy or cystoscopic exam and urine cytology at least 6 weeks from last BCG treatment
• ECOG performance status 0-1
• Adequate bone marrow, renal, liver and coagulation function

Exclusion Criteria:

• Pregnant or nursing
• HIV positive
• Use of anticoagulants such as coumadin or heparin
• History of bleeding disorder
• Active systemic autoimmune disease or chronic immunodeficiency
• Prior gene therapy
• Uncontrolled cystitis, bladder pain, bladder spasms, urinary incontinence, or reduced bladder volume