Fusion Pharmaceuticals Announces First Patient Dosed in Phase 1 Study of FPI-2059, a Targeted Alpha Therapy (TAT) for the Treatment of Solid Tumors Expressing NTSR1
Fusion Pharmaceuticals Inc., a clinical-stage oncology company focused on developing next-generation radiopharmaceuticals as precision medicines, today announced that the first patient has been dosed in the Phase 1 study evaluating [225Ac]-FPI-2059 (FPI-2059). FPI-2059 is a small molecule targeted alpha therapy (TAT) designed to deliver actinium-225 to tumor sites expressing neurotensin receptor 1 (NTSR1), a protein that is overexpressed in gastrointestinal, prostate, pancreatic ductal adenocarcinoma (PDAC) and multiple other cancers.
"Tremendous opportunity exists in the radiopharmaceutical field to look beyond the few established targets, particularly when using a potent payload like actinium-225. The initiation of the Phase 1 study of FPI-2059 marks an important milestone in this regard, bringing us a step closer to providing a differentiated therapy for patients," said Chief Executive Officer, John Valliant, Ph.D. "FPI-2059 is our fourth clinical program and the second small molecule-based TAT in our pipeline of radiopharmaceuticals, showcasing the potential for our platform technology to create TATs that treat a broad array of solid tumor types with high unmet need."
Fusion acquired [177Lu]-IPN-1087 (IPN-1087), a lutetium-based beta-emitting radiopharmaceutical, from Ipsen in April 2021, and converted the compound to the alpha-emitting FPI-2059. In clinical studies, IPN-1087, also referred to as 3BP-227, showed promising early safety data, evidence of anti-tumor activity and uptake in multiple tumor types based on imaging of the distribution of the drug in patients. Fusion showed that in preclinical models, replacing the beta emitter with an alpha emitter resulted in responses at 1,500 times lower administered doses.
The Phase 1, multi-center, open-label clinical trial is designed to investigate the safety, tolerability, dosimetry, biodistribution, and pharmacokinetics of FPI-2059 as well as preliminary anti-tumor activity in participants with neurotensin receptor 1 (NTSR1) expressing advanced metastatic solid tumors. The study will employ a 3+3 dose escalation design to identify the recommended Phase 2 dose (RP2D) of FPI-2059 administered intravenously every 56 days for up to four cycles.
Fusion plans to provide guidance on timing for pharmacokinetic, imaging and safety data following early experience with FPI-2059 patient screening and enrollment.
About FPI-2059
FPI-2059 is a small molecule radiopharmaceutical targeting neurotensin receptor 1 (NTSR1) which is overexpressed in multiple solid tumors, including pancreatic ductal adenocarcinoma, colorectal, squamous cell carcinoma head & neck, gastric, Ewings sarcoma, and neuroendocrine differentiated prostate. FPI-2059 is based upon a compound previously referred to as IPN-1087 and 3BP-227 that had previously been studied in investigator sponsored studies and a Phase 1 clinical trial as a beta-emitting radiopharmaceutical. Fusion acquired the asset in 2021 and converted it to an alpha-emitting radiopharmaceutical using actinium-225. The diagnostic analogue which uses indium-111 in place of actinium-225 is referred to as FPI-2058.
About Fusion
Fusion Pharmaceuticals is a clinical-stage oncology company focused on developing next-generation radiopharmaceuticals as precision medicines. Fusion connects alpha particle emitting isotopes to various targeting molecules to selectively deliver the alpha emitting payloads to tumors. Fusion's clinical portfolio includes: FPI-2265 targeting prostate specific membrane antigen (PSMA) for the treatment of metastatic castration resistant prostate cancer, currently in a Phase 2 trial; FPI-1434 targeting insulin-like growth factor 1 receptor, currently in a Phase 1 trial; FPI-1966 targeting the fibroblast growth factor receptor 3 (FGFR3), currently in a Phase 1 trial; and FPI-2059, a small molecule targeting neurotensin receptor 1 (NTSR1), currently in a Phase 1 trial. In addition to a robust proprietary pipeline, Fusion has a collaboration with AstraZeneca to jointly develop novel targeted alpha therapies (TATs) and combination programs between Fusion's TATs and AstraZeneca's DNA Damage Response Inhibitors (DDRis) and immuno-oncology agents. Fusion has also entered into a collaboration with Merck to evaluate FPI-1434 in combination with Merck's KEYTRUDA® (pembrolizumab) in patients with solid tumors expressing IGF-1R. To support Fusion's growing pipeline of TATs, the company has signed strategic actinium supply agreements with TRIUMF, Niowave, Inc. and BWXT Medical.
SOURCE: Fusion Pharmaceuticals
21 March 2023