Actinium Pharmaceuticals, Inc.

Actinium is hiring a Senior Clinical Trial Manager! Please visit our careers page to to view the job description for this exciting role. Interested candidates can contact Julie Gibson https://lnkd.in/e6u8DdyW

Actinium Pharmaceuticals announced compelling preclinical data for ATNM-400, a first-in-class Actinium-225 (AC-225) antibody radioconjugate, in hormone receptor positive (HR+), HER2 positive (HER2+) and triple-negative breast cancer (TNBC) that will be presented at the San Antonio Breast Cancer Symposium being held December 10‑14, 2025 in San Antonio, Texas. The data demonstrates significant anti-tumor activity in breast cancer models resistant to standard-of-care therapies including endocrine therapy tamoxifen and HER2-targeted therapy trastuzumab (Herceptin, Roche) as well as potent tumor growth inhibition in TNBC models. ATNM-400 SABCS Presentation Details Abstract Title: Anti-tumor activity of ATNM-400, a first-in-class Actinium-225 antibody radioconjugate, in tamoxifen and trastuzumab resistant breast cancer models Date & Time: December 11, 2025, 5:00 PM – 6:30 PM CT Abstract Number: 2069 Presentation Number: PS4‑04‑26 Date/Time: Thursday, December 11, 2025, 5:00 PM–6:30 PM CT Session: Poster Session 4 Read the press release for more details: https://lnkd.in/gKPht2ct #Radiotherapy #Oncology #CancerResearch #BreastCancer #SABCS25

Actinium is hiring! We are looking for a Senior Research Associate to join our R&D team to work on highly innovative targeted radiotherapies. https://lnkd.in/e6u8DdyW

Actinium Highlights Expanded Data Set for ATNM-400 in Prostate Cancer Demonstrating Superior Efficacy to Enzalutamide and Ability to Overcome Resistance to ARPI Therapy and PSMA-Ac-225/Lu-177 Labelled Radiotherapy at the Society of Nuclear Medicine & Molecular Imaging Annual Meeting. Read the press release: https://bit.ly/4jYVkX7 #SNMMI25

Actinium Announces Enrollment of First Patient in the Iomab-ACT Commercial CAR-T Trial at the University of Texas Southwestern Medical Center. Read the press release: https://bit.ly/3RQW8lu #utswmed #radiotherapy

Wrapping up an incredible #AACR25! Our team was pleased by the positive response to our posters on ATNM-400 and Actimab-A. A huge thank you to the AACR community for the insightful discussions and interest. Stay tuned for more updates. Both of our abstracts can be found here: https://bit.ly/3EUvDIG #Radiotherapy

Actinium (NYSE: ATNM) Presents Data Showing ATNM-400 is More Efficacious than Pluvicto and is Highly Efficacious after Pluvicto Resistance in Prostate Cancer Tumor Models at the American Association for Cancer Research Annual Meeting. Read the press release here: https://bit.ly/42NuI4P #AACR25

Actinium Highlights Mutation Agnostic Antileukemic Activity of Actimab-A Against FLT3, NPM1, KMT2A and TP53 Mutations in AML Models Demonstrating Backbone Potential for Acute Myeloid Leukemia Treatment at the #AACR25. Read the press release here: https://bit.ly/42w85TG

Actinium is looking forward to presenting ATNM-400 data at #AACR25 today. The abstract includes results from in vitro and in vivo studies, including biodistribution imaging and efficacy analyses with various dose levels of ATNM-400. https://bit.ly/41OmjPt

Initial preclinical data from ATNM-400 will be presented at #AACR25 in Chicago on April 27, 2025, 2:00 pm – 5:00 pm CT. Actinium continues to advance ATNM-400 with additional data expected from Pluvicto-resistant prostate cancer models at AACR. Highlights from the abstract include: • ATNM-400 selectively binds to prostate cancer cells, undergoes rapid internalization, and induces dose-dependent cytotoxicity. • In prostate cancer xenograft mouse models, ATNM-400 accumulated in tumors for up to 144 hours, while showing minimal uptake in normal tissues. • Small animal SPECT/CT imaging with Indium-111-labeled antibody confirmed selective tumor accumulation and clearance from healthy tissues. • A single dose of ATNM-400 achieved 68.5% tumor growth inhibition at 20 µCi/kg and 99.8% at 40 µCi/kg, with all doses being well tolerated. ATNM-400 AACR Presentation Details: • Title: ATNM-400 is a novel Actinium-225 antibody radioconjugate with strong efficacy in preclinical models of prostate cancer • Abstract Number: 578 • Session: PO.ET08.01 - Theranostics and Radiotheranostics • Date & Time: April 27, 2025 – 2:00 pm – 5:00 pm CT More details here: https://bit.ly/41OmjPt #Oncology #Pharma #CancerResearch