Background and Update for S1602 “A Phase III Randomized Trial to Evaluate the Influence of BCG Strain Differences and T Cell Priming with Intradermal BCG Before Intravesical Therapy for BCG-naïve High-grade Non-muscle-invasive Bladder Cancer

The S1602 Intergroup trial is a randomized phase III clinical trial that aims to test two important hypotheses: (1) priming with intradermal bacillus Calmette-Guérin (BCG) vaccine prior to standard intravesical BCG improves response to BCG in terms of recurrence-free survival and (2) Tokyo-172 BCG strain is non-inferior to TICE BCG in terms of time to high-grade recurrence. The study was approved by the Cancer Therapy Evaluation Program of the National Cancer Institute and activated in spring 2017. Here, we provide a synopsis of the study background, design, and update of the clinical trial. The S1602 Intergroup trial is a randomized phase III clinical trial that aims to evaluate the efficacy of priming with intradermal bacillus Calmette-Guérin (BCG) vaccine prior to standard intravesical BCG and to compare different BCG strains (TICE vs Tokyo-172). The study has enrolled over 100 of 969 planned patients.