In phase 1, cohort 1, the potential impact of pre-dose administration of vofatamab on the dosimetry, PK, safety, and tolerability of [225Ac]-FPI-1966 and [111In]-FPI-1967 will be evaluated.~In later phase 1 cohorts, [225Ac]-FPI-1966 will be evaluated at ascending dose levels. Participants will receive [111In]-FPI-1967 during the imaging screening period to assess FGFR3 expression and to determine biodistribution and estimate radiation exposure to critical organs.~Once the recommended phase 2 dose (RP2D) or regimen is established and confirmed, three tumour-agnostic expansion cohorts may be initiated in parallel.
This first-in-human study evaluates safety, tolerability and distribution of [225Ac] FPI-1966, [111In]-FPI-1967, and vofatamab in patients with FGFR3-expressing solid tumors.