Dose Escalation Study of ADXS31-164 in Subjects With HER2 Expressing Solid Tumors

This is a Phase 1b, dose-escalation, open-label study in subjects with HER2 expressing solid tumors. Subjects will receive escalating doses of ADXS31-164 every 3 weeks during a 12-week treatment cycle. Subjects will receive a prophylactic regimen completed at least 30 minutes prior to each ADXS31-164 infusion to mitigate and manage the potential immune response seen with immunotherapy administration. In addition, all subjects will participate in a 3 year Lm surveillance period. The surveillance period will begin following the last dose of study treatment or at the time of study discontinuation. This period is intended to help ensure the eradication of Lm bacteria. This period will also include a 6- month course of trimethoprim/sulfamethoxazole which will be initiated approximately 72 hours after the completion of the last dose of ADXS31-164 or immediately following study discontinuation. In subjects with a sulfa allergy, the 6-month course should consist of ampicillin 500 mg 4 times daily initiated approximately 72 hours following the last dose of study treatment or immediately following study discontinuation. Dose escalations and de-escalations will be dictated by a 3+3 design. Three dose levels may be evaluated during the dose escalation portion starting with Dose Level 1 at 1 x 109 colony forming units (CFU). Once the Maximum Tolerated Dose (MTD) and RP2D have been identified, up to 4 HER2 overexpressing tumor specific expansion cohorts will be evaluated. The specific tumor types included in the expansion cohorts may include breast and gastric cancer with the remaining to be determined by the sponsor after review of data from Part A. Treatment cycles can be repeated at the RP2D (or less) for each subject for up to 2 years, until a study discontinuation criterion is met or he/she has completed \>6 months of study therapy and at least 1 cycle of treatment post observation of a complete response (CR)