The Fusion Pipeline


[225Ac]-FPI-1434 is our lead clinical candidate that was engineered to deliver alpha particles to cancer cells. The new drug was created by combining an antibody for an established cancer biomarker, IGF-1R, with our Fast-Clear™ Linker Technology to create a targeted alpha therapeutic that has the potential to be used across multiple tumor types.

The first human trial of [225Ac]-FPI-1434 is actively recruiting. For more information or questions about trial eligibility, please contact Fusion.

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Trial Overview

The Phase 1 clinical study is a dose-escalation study that will characterize the safety and tolerability of a single dose [225Ac]-FPI-1434 Injection in patients with advanced solid tumors. [225Ac]-FPI-1434 is a targeted alpha radioimmunoconjugate that consists of a humanized monoclonal antibody targeting the insulin-like growth factor-1 receptor 1 (IGF-1R), our Fast-Clear™ linker technology, a bifunctional chelate, and actinium-225.

Patients will initially be screened using the imaging agent [111In]-FPI-1547. [111In]-FPI-1547 contains the same targeting antibody and bifunctional chelate as the [225Ac]-FPI-1434 therapeutic form. However, it will contain indium-111 in place of actinium-225, allowing standard clinical imaging techniques to be used to visualize tumor uptake.

Only patients who exhibit uptake of the imaging agent in their tumors as detected by single photon emission computed tomography (SPECT) will receive the [225Ac]-FPI-1434 therapeutic radioimmunoconjugate. Investigators will evaluate the safety and tolerability of a targeted alpha-emitting radiotherapeutic. Fusion will be treating up to 30 patients.