* Phase 1: Cell dose escalation to identify the maximum dose of BPX-603 administered without or with rimiducid. The first subject in each dose cohort will receive BPX-603 alone (without rimiducid) in order to assess safety of the CAR-T monotherapy.
* Phase 2: Indication-specific dose expansion to assess the safety, pharmacodynamics (including BPX-603 persistence and response to temsirolimus as applicable), and clinical activity at the recommended dose for expansion (RDE) identified in Phase 1 in various HER2+ solid tumors.
* During Phase 1 or 2, temsirolimus (single IV dose at 25 mg) may be administered following BPX-603 infusion in response to treatment-emergent toxicity in order to activate the iRC9 safety switch.
