Actinium Pharmaceuticals

ATNM

Market cap $45.5M

ATNM-400 is advancing as a first-in-class, multi-tumor Actinium-225 radiotherapy candidate with activity across prostate and lung cancers, two of the largest cancer indications globally New preclinical findings demonstrate ATNM-400 overcomes resistance to the EGFR inhibitor osimertinib in EGFR-mutated NSCLC, addressing a major unmet clinical need NEW YORK , Oct. 13, 2025 /PRNewswire/ -- Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM), a leader in the development of differentiated targeted radiotherapies, today announced that the first-ever preclinical data from its ATNM-400 program in non-small cell lung cancer (NSCLC) 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 (Ac-225) antibody radioconjugate with preclinical data in both prostate cancer and NSCLC.

-   ATNM-400 targets a highly differentiated, non-PSMA antigen associated with the development and progression of prostate cancer, exhibiting potent therapeutic activity independent of PSMA expression levels -   Extended follow-up in prostate cancer models demonstrated durable anti-tumor responses with ATNM-400, exceeding those achieved with the androgen receptor pathway inhibitor (ARPI), enzalutamide NEW YORK , Oct. 13, 2025 /PRNewswire/ -- Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) (Actinium or the Company), a pioneer in the development of differentiated targeted radiotherapies, today announced that compelling preclinical data for ATNM-400, its novel, first-in-class antibody radioconjugate armed with the potent alpha-emitter Actinium-225 (Ac-225), has been accepted for presentation at the 32nd Annual Prostate Cancer Foundation (PCF) Scientific Retreat being held on October 23 – 25, 2025 in Carlsbad, CA. The presentation will highlight ATNM-400's ability to induce robust, durable anti-tumor activity in metastatic castration-resistant prostate cancer (mCRPC) models, including tumors resistant to standard-of-care therapies such as the androgen receptor pathway inhibitor (ARPI), enzalutamide (Xtandi®, Astellas/Pfizer) and the PSMA-targeted therapy, 177Lu-PSMA-617 (active agent in Pluvicto®, Novartis) as well as superior efficacy compared to 225Ac-PSMA-617.

Here is how Actinium Pharmaceuticals (ATNM) and Avadel (AVDL) have performed compared to their sector so far this year.

-     ATNM-400 demonstrates robust efficacy in prostate cancer tumor models with acquired resistance to Pluvicto ® and enzalutamide, follow-up continues -     ATNM-400 significantly improved survival compared to the approved prostate cancer treatment Pluvicto ®, the first blockbuster radiotherapy -     In combination with enzalutamide, an approved ARPI therapy, ATNM-400 produced enhanced efficacy with 40% of prostate cancer tumor-bearing animals achieving complete cures NEW YORK , July 31, 2025 /PRNewswire/ -- Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) (Actinium or the Company), a pioneer in the development of targeted radiotherapies, today reported additional preclinical data supporting its ATNM-400 radiotherapy prostate cancer candidate at the 4th Annual Targeted Radiopharmaceuticals Summit (TRP) being held July 29 – 31, 2025 in San Diego, CA. ATNM-400 is a novel, first-in-class targeted radiotherapy designed to deliver potent Actinium-225 (Ac-225), an alpha-emitter radioisotope, to prostate cancer cells by targeting a non-Prostate Specific Membrane Antigen (PSMA), disease-driving protein overexpressed in advanced and treatment-resistant disease.

-  ATNM-400 shows; superior prostate cancer cell killing compared to androgen receptor inhibitor Xtandi® (enzalutamide), the ability to overcome Xtandi resistance, and activity in combination -  ATNM-400 is more efficacious than both Pluvicto® (177-Lu-PSMA-617) and Ac-225-PSMA-617 targeted radiotherapy in prostate cancer in vitro and in vivo models and overcome resistance in prostate cancer tumors that failed Pluvicto® therapy -  ATNM-400's target is highly differentiated from PSMA as it is implicated in disease biology, contributing to disease progression, faster progression to castration resistance and poorer survival outcomes with target expression reported following androgen receptor inhibitor and PSMA radiotherapy -  Data further supports ATNM-400's potential to address critical gaps in prostate cancer treatment as a monotherapy or in sequence with other therapeutic modalities NEW YORK , June 23, 2025 /PRNewswire/ -- Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) (Actinium or the Company), a pioneer in the development of targeted radiotherapies, today reported new preclinical data from its first-in-class, non-PSMA targeting radiotherapy prostate cancer candidate ATNM-400, that leverages the potent alpha-particle emitter Actinium-225 (Ac-225) isotope, at the Society of Nuclear Medicine & Molecular Imaging (SNMMI) annual meeting being held June 21 st – 24th, 2025, in New Orleans, Louisiana. The data presented at SNMMI showed ATNM-400 has superior potency compared Xtandi® (enzalutamide) and is highly efficacious in Xtandi® resistant prostate models.

NEW YORK , June 10, 2025 /PRNewswire/ -- Kuehn Law, PLLC, a shareholder litigation law firm, is investigating whether certain officers and directors of Actinium Pharmaceuticals, Inc. (NYSE: ATNM)  breached their fiduciary duties to shareholders.  According to a federal securities lawsuit, Insiders at Actinium Pharmaceuticals caused the company to misrepresent or fail to disclose that (1) the Company's data from the Sierra Trial was unlikely to satisfy the FDA's guidelines for the acceptance and approval of Iomab-B BLA; (2) the additional analyses, including long-term follow-ups that purportedly demonstrated a trend towards improved Overall Survival that the Company provided to the FDA in an attempt to mitigate Sierra's poor OS data were unlikely to satisfy the FDA's guidelines for the acceptance and approval of Iomab-B BLA; (3) as a result, the FDA would likely refuse to review the Iomab-B BLA or, if it did consider that BLA, that the application in its current form was unlikely to be approved; and (4), as a result, positive statements about the Company's business, operations, and prospects were materially misleading and/or lacked a reasonable basis.

NEW YORK, NY / ACCESS Newswire / May 27, 2025 / If you suffered a loss on your Actinium Pharmaceuticals, Inc. (NYSE:ATNM) investment and want to learn about a potential recovery under the federal securities laws, follow the link below for more information: https://zlk.com/pslra-1/actinium-lawsuit-submission-form?prid=150393&wire=1&utm_campaign=21 or contact Joseph E. Levi, Esq.

NEW YORK, NY / ACCESS Newswire / May 27, 2025 / If you suffered a loss on your Actinium Pharmaceuticals, Inc. (NYSE:ATNM) investment and want to learn about a potential recovery under the federal securities laws, follow the link below for more information: https://zlk.com/pslra-1/actinium-lawsuit-submission-form?prid=150356&wire=1&utm_campaign=19 or contact Joseph E. Levi, Esq.

NEW YORK, NY / ACCESS Newswire / May 27, 2025 / Rosen Law Firm: WHY: Rosen Law Firm, a global investor rights law firm, reminds purchasers of securities of Actinium Pharmaceuticals, Inc. (NYSE American:ATNM) between October 31, 2022 and August 2, 2024, both dates inclusive (the "Class Period"), of the important May 27, 2025 lead plaintiff deadline. SO WHAT: If you purchased Actinium securities during the Class Period you may be entitled to compensation without payment of any out of pocket fees or costs through a contingency fee arrangement.

NEW YORK, NY / ACCESS Newswire / May 26, 2025 / If you suffered a loss on your Actinium Pharmaceuticals, Inc. (NYSE:ATNM) investment and want to learn about a potential recovery under the federal securities laws, follow the link below for more information: https://zlk.com/pslra-1/actinium-lawsuit-submission-form?prid=150273&wire=1&utm_campaign=13 or contact Joseph E. Levi, Esq.