NEW YORK – Precirix said on Thursday it has dosed the first patient in a Phase I/II trial of its precision radiopharmaceutical, called CAM-H2, in HER2-positive metastatic breast and gastric or gastroesophageal cancer.
Brussels-based Precirix will enroll up to 70 patients in the trial with HER2-positive metastatic breast and gastric or gastroesophageal cancer who are relapsed or refractory to available anti-HER2 therapies. The trial will also enroll patients whose cancers have spread to the brain.
The first stage of the study will evaluate three dose levels of CAM-H2 with at least three patients in each dose cohort. In the second stage, researchers will enroll up to 70 patients, give them the recommended Phase II dose, and evaluate their objective response and clinical benefit rate on treatment.
Researchers will also assess progression-free survival in the entire study population and in patients with brain metastases, duration of response, overall survival, and the proportion of patients who develop anti-drug antibodies from treatment.
CAM-H2 is a single-domain HER2-targeting antibody that is covalently linked to iodine-131. Previous studies of the drug showed that CAM-H2 was able to cross the blood-tumor barrier and target HER2-positive brain lesions in breast cancer patients. In a comparative preclinical trial, CAM-H2 increased survival in mice compared to Genentech's HER2-targeted therapy trastuzumab (Herceptin).