no). The intent for stratification is to ensure balance between treatment groups with respect to these important prognostic factors. A block size of 3 was chosen to control for potential imbalance between the three treatment groups. Given the limited sample size, a formal subgroup analysis based on the stratification variables will not be undertaken. Patients who will not receive BCG will be consecutively allocated (non-randomized) into Arm 4 consisting of vaccine monotherapy. Protocol Version 7.0 was updated to allow a temporary revision to the randomization algorithm due to delays in the batch release of certain doses of vaccine. This allowed the randomization schedule to be temporarily revised from a 1:1:1 randomization to a 1:1 randomization, with one arm being briefly Heat Biologics, Inc. Protocol HS410-101 HS410-101 SAP version 1.0 Page 14 of 25 suspended. The batch was released in time such that this change was never implemented; the randomization algorithm was never changed during the study. The randomization schedule will be prepared by an independent statistician not otherwise involved with this study, and will be implemented through an interactive web based system. The study will be single- blinded (physician-patient). 3.5 Study Variables In general, the schedules of assessments (SOA) are divided into an induction and maintenance phase. In the phase 1 component of the study, the induction phase will consist of 6 weekly vaccine doses, a one week drug free period and then followed by 6 more weekly doses. The maintenance phase will then consist of monthly treatments for 3 doses for up to a total of 15 doses, unless the criteria for treatment discontinuation are met. In the phase 2 component of the study, the induction phase will consist of 6 weekly HS-410 (or placebo) doses in combination with 6 doses of BCG, followed by 6 weeks of HS-410 or placebo monotherapy with a vaccine holiday on Week 13 to allow for disease assessment. This will be followed by a maintenance phase consisting of 3 courses of three once-weekly injections in combination with intravesical maintenance BCG for a total of 21 doses, unless the criteria for treatment discontinuation are met. Additional maintenance therapy will be at the discretion of the treating physician.