Actinium Pharmaceuticals to announces preclinical data from ATNM-400 program

Actinium Pharmaceuticals (ATNM) announced that the first-ever preclinical data from its ATNM-400 program in non-small cell lung cancer has been accepted for presentation at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics being held October 22 – 26, 2025, at the Hynes Convention Center in Boston, Massachusetts. ATNM-400 is a highly innovative, first-in-class, Actinium-225 antibody radioconjugate with preclinical data in both prostate cancer and NSCLC. Together, these two indications represent more than 500,000 new cases annually in the U.S. alone. NSCLC accounts for approximately 85% of lung cancer cases and remains the leading cause of cancer mortality worldwide. While EGFR tyrosine kinase inhibitors such as osimertinib have transformed outcomes for patients with EGFR-mutant NSCLC, virtually all patients develop resistance within 2 to 3 years, leading to disease progression and a lack of effective therapeutic options. Preclinical data to be presented at AACR-NCI-EORTC conference demonstrate that ATNM-400 exerts potent anti-tumor activity in EGFR-mutant NSCLC models and is capable of overcoming resistance to osimertinib and is furthermore synergistic in combination osimertinib. This represents a potential breakthrough for patients with relapsed or refractory EGFR-mutant NSCLC, one of the most urgent areas of unmet need in oncology. In the multicenter, single-arm Phase 2 trial titled “osimertinib plus consolidative radiotherapy for advanced EGFR-mutant non-small cell lung cancer,” Sampath et al. reported a median progression-free survival of 32.3 months. This reflects a notable 12.3-month improvement over the 20.0-month median PFS observed with osimertinib monotherapy, as reported by Watanabe et al. in a real-world clinical setting.