Actinium Pharmaceuticals Showcases ATNM-400 Antitumor Activity at EANM 2026

Actinium Pharmaceuticals, Inc. has announced key presentations at the 39th Annual Congress of the European Association of Nuclear Medicine (EANM), held from October 17 to 21, 2026, in Vienna, Austria. The focus of these presentations is on preclinical data demonstrating the broad potential of ATNM-400, the company's first-in-class Actinium-225 (²²⁵Ac) radiotherapy, in various cancer models, including non-small cell lung cancer (NSCLC), colorectal cancer, and ovarian cancer.

In NSCLC, ATNM-400 exhibited antitumor activity as a standalone treatment and showed enhanced effects when combined with KRAS or ALK inhibitors in resistant models. These results build upon earlier findings concerning EGFR-mutant cases and underline the mutation-agnostic potential of ATNM-400.

For colorectal cancer, ATNM-400 displayed effectiveness both as a monotherapy in SW620 xenografts and in combination with bevacizumab and oxaliplatin in HCT15 xenografts, demonstrating enhanced activity in a model that previously had limited responses to standard treatments.

In the context of ovarian cancer, ATNM-400 provided durable antitumor activity, including in models resistant to bevacizumab, supporting its potential as a treatment option in recurrent disease scenarios.

The data presented indicate that ATNM-400 may serve both as a monotherapy and in conjunction with established cancer treatments, suggesting its versatility in addressing multiple solid tumor indications.

Sandesh Seth, Chairman and CEO of Actinium, remarked on the promising findings, emphasizing their commitment to expanding targeted radiotherapy options across significant solid tumor indications. He noted the importance of ATNM-400's capability to address a wide lung cancer demographic, irrespective of oncogenic mutations, while also highlighting the opportunities it presents in colorectal and ovarian cancer areas with unmet medical needs.

Presentation Details at EANM 2026

• Abstract Title: ATNM-400 Elicits Durable Anti-tumor Responses in KRAS- and ALK-Driven NSCLC Models in a Mutation-Agnostic Manner
• Abstract Number: EPS-149
• Presentation Type: Oral presentation
• Session Date & Time: Monday, October 19, 2026, 4:45–6:15 p.m. CEST
• Location: Hall G2
• Abstract Title: ATNM-400, a First-in-Class Actinium-225 Radioconjugate Improves Response to Standard-of-Care Therapeutics in Colorectal Cancer Models
• Abstract Number: EP-0163
• Presentation Type: e-Poster
• Abstract Title: ATNM-400, a First-in-Class Actinium-225 Radioconjugate Triggers Durable Antitumor Responses in Ovarian Cancer Models
• Abstract Number: EP-0176
• Presentation Type: e-Poster