Alpha-9 Oncology Initiates Phase 1 Clinical Trial of GRPR-Targeted Radiotherapy, First Patient Dosed

Alpha-9 Oncology, a U.S. clinical-stage radiopharmaceutical company, recently announced that the first patient has been dosed in its Phase 1 clinical trial evaluating two GRPR-targeted radiopharmaceuticals. The study involves the actinium-225-labeled compound 225Ac-A9-0642 and the lutetium-177-labeled compound 177Lu-A9-0631, primarily enrolling patients with breast cancer and other solid tumors, with data expected to be released by the end of 2027.

According to the company, both 225Ac-A9-0642 and 177Lu-A9-0631 target the gastrin-releasing peptide receptor (GRPR). GRPR is considered a solid tumor-associated target with potential clinical application value in breast cancer and other solid tumors. 225Ac-A9-0642 is Alpha-9's first actinium-225 GRPR-targeted compound to enter clinical evaluation, while 177Lu-A9-0631 is a lutetium-177 GRPR-targeted compound.

This Phase 1 study will evaluate the safety, tolerability, dosimetric characteristics, and recommended dose of both investigational candidates in patients with GRPR-positive advanced or metastatic tumors. Patient screening will be conducted using the company's proprietary GRPR imaging compound 68Ga-A9-6217.

Alpha-9 Oncology stated that its radiopharmaceutical development employs a modular molecular engineering approach, optimizing combinations of components such as binders, linkers, chelators, and radioisotopes, with the goal of enhancing tumor retention while reducing healthy tissue exposure. The company noted that early diagnostic imaging data demonstrate favorable tumor-targeting performance of 68Ga-A9-6217 with limited uptake in healthy organs. Additionally, early results from compassionate use of 177Lu-A9-0631 indicate good tolerability in patients with GRPR-positive tumors.