This study is a two part study: Phase I and Phase II. The Phase 1 portion is an open-label, safety study. Patients will have previously received 3-6 instillations of weekly intravesical Bacillus Calmette-Guerin (BCG) induction therapy (as standard of care) followed by low dose intradermal (1*10^6 cells) HS-410 monotherapy. In Phase 2, patients will be assigned to treatment groups based on whether they will receive induction BCG in the typical post-TURBT window. If the investigator plans to administer BCG, patients will be randomized to one of three blinded (physician-patient), placebo-controlled groups and receive either intradermal placebo or low dose (1*10^6 cells) or high dose (1*10^7 cells) vesigenurtacel-L in combination with induction and maintenance intravesical BCG. If patients will not receive BCG, they will be enrolled into an open-label, non-randomized group and receive high dose (1*10^7 cells) intradermal HS-410 monotherapy.
Phase I/II study: Phase 1 is an open-label, safety study, patients who previously received 3-6 instillations of weekly intravesical Bacillus Calmette-Guerin (BCG) induction therapy (as standard of care) followed by low dose intradermal (1*10^6 cells) HS-410 monotherapy. Phase 2, patients will be randomized to one of three blinded (physician-patient), placebo-controlled groups and receive either intradermal placebo or low dose (1*10^6 cells) or high dose (1*10^7 cells) vesigenurtacel-L in combination with induction and maintenance intravesical BCG. Patients who do not receive BCG will be enrolled into an open-label, non-randomized group receiving high dose (1*10^7 cells) intradermal HS-410 monotherapy.