177Lu-BetaBart in Patients With Relapsed/Refractory, Locally Advanced Inoperable, or Metastatic Solid Tumors

The main objectives of the study are to establish the safety, recommended Phase 2 dose (RP2D), pharmacokinetics (pk), and preliminary anti-tumour activity of 177Lu-BetaBart, a lutetium-labeled anti-B7-H3 monoclonal antibody, in patients with solid tumors who may benefit from this treatment and who meet the study eligibility criteria. The study is divided into 2 phases. Phase 1 is the dose escalation phase to establish the safety profile of 177Lu-BetaBart and to determine the maximum tolerated dose (MTD) and/or RP2D of 177Lu-BetaBart. Phase 2a is the dose expansion phase to evaluate preliminary anti-tumor activity and to confirm the safety of 177Lu-BetaBart in select patient populations. Each phase consists of a Screening Period, a Treatment Period, and a Safety and Long-term Follow-up Period. The estimated total time on study is 22 weeks excluding the Long-term Follow-up Period.