Actinium Appoints Accomplished Oncology Expert Steffen Heeger MD, MSc as Chief Medical Officer to Drive Rejuvenated Pipeline Development

Proven Chief Medical Officer at several publicly listed and clinical-stage oncology companies with successful track record developing multiple modalities including radiotherapies from preclinical through global approvals across hematologic malignancies and solid tumors Played a leading role in clinical development and worldwide approvals of Erbitux® at Merck KGaA leading to its blockbuster status Led clinical development as CMO of NBE Therapeutics which was acquired by Boehringer Ingelheim for $1.4 billion, and most recently CMO of radiotherapy company Full-Life Technologies Timely key hire with Dr. Heeger's operational rigor and clinical expertise expected to elevate development of Actimab-A, ATNM-400, and Iomab-ACT as Actinium advances toward key data readouts and expanded clinical trials in 2H:2026 NEW YORK, June 1, 2026 /PRNewswire/ -- Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) (Actinium or the Company), a pioneer in the development of targeted radiotherapies, today announced the appointment of Steffen Heeger, MD, MSc, as Chief Medical Officer. Dr. Heeger brings a rare combination of radiotherapy expertise, global oncology drug development leadership, and public-company experience.