Actinium Pharmaceuticals Appoints Radiotherapy Expert Steffen Heeger as Chief Medical Officer
Key Insights
Actinium Pharmaceuticals has appointed Steffen Heeger (search), MD, MSc, as Chief Medical Officer, bringing extensive radiotherapy expertise and a track record of developing multiple oncology programs from preclinical through global approvals.
Dr. Heeger previously led clinical development of blockbuster drug Erbitux at Merck KGaA and served as CMO at NBE Therapeutics (search), which was acquired by Boehringer Ingelheim for $1.4 billion.
The appointment comes as Actinium prepares to advance its targeted radiotherapy pipeline, including Actimab-A (search), ATNM-400 (search), and Iomab-ACT, toward key data readouts and expanded clinical trials in the second half of 2026.
Actinium Pharmaceuticals announced the appointment of Steffen Heeger (search), MD, MSc, as Chief Medical Officer, bringing a rare combination of radiotherapy expertise and global oncology drug development leadership to the targeted radiotherapy company. Dr. Heeger's appointment comes at a pivotal moment as Actinium prepares to advance its pipeline toward key data readouts and expanded clinical trials in the second half of 2026.
Proven Track Record in Oncology Development
Dr. Heeger brings extensive experience translating multiple programs from IND submission through global clinical approval in the US, EU, and Japan. His career highlights include leading the global clinical development and life cycle management for Erbitux® (cetuximab) at Merck KGaA, contributing to its blockbuster status across colorectal, head and neck, gastric, and lung cancers in major markets including the US, Europe, Japan, and China.
Most recently, Dr. Heeger served as Chief Medical Officer of Full-Life Technologies (search), where he led the translation of three targeted radioconjugate compounds from preclinical to clinical stage within two years, securing IND clearance and fast track designation. His work included advancing an anti-PSMA (search) program in metastatic castration-resistant prostate cancer (search), directly relevant to Actinium's ATNM-400 (search) asset.
Strategic Leadership Experience
Dr. Heeger's leadership has been instrumental in significant corporate transactions. As CMO of NBE-Therapeutics, he led the IND submission and initial clinical trial of NBE-002, a first-in-class immune-stimulatory antibody-drug conjugate targeting ROR1 in triple-negative breast cancer (search), non-small cell lung cancer (search), and sarcoma (search). NBE-Therapeutics was subsequently acquired by Boehringer Ingelheim for $1.4 billion.
Earlier in his career, he served as Vice President, Head of Clinical Development at MorphoSys AG, where he led clinical strategy and execution for hematology and oncology programs, including monoclonal antibody therapeutics targeting CD19 (search), CD38 (search), and PSMA (search).
Alignment with Actinium's Pipeline
"Steffen's background is uniquely suited to unlock the value in Actinium's pipeline," said Sandesh Seth, Chairman and Chief Executive Officer of Actinium Pharmaceuticals. "He has successfully taken multiple targeted oncology and radiotherapy programs from the lab into patients, including anti-PSMA (search) programs directly relevant to our ATNM-400 (search) asset, and has deep experience navigating global regulatory pathways with the FDA and international agencies."
Dr. Heeger's experience spans both hematologic malignancies (search) and solid tumors (search), aligning with Actinium's strategic focus. His direct experience with alpha-emitting radiotherapies and translational medicine positions him to advance Actinium's clinical programs across three key areas: solid tumor therapeutics including ATNM-400 (search) and Actimab-A (search), therapeutic applications for acute myeloid leukemia (search) and myelodysplastic syndrome (search), and targeted conditioning agents for bone marrow transplant and cell and gene therapy.
Pipeline Advancement Plans
ATNM-400 (search) targets a novel antigen distinct from PSMA (search) and has demonstrated preclinical activity across metastatic castration-resistant prostate cancer (search), non-small cell lung cancer (search), and breast cancer (search). Actimab-A (search) has shown improved survival in relapsed/refractory AML with CLAG-M and is advancing toward a Phase 2/3 trial, with additional development ongoing through a CRADA with the National Cancer Institute.
"Actinium is developing what I believe is one of the most compelling radiotherapy pipelines today," said Dr. Heeger. "Their biology-driven R&D has yielded several highly differentiated, even unique, assets that offer real opportunity to bring transformative therapies to patients with limited options. Their assets have nothing comparable being developed and each has blockbuster potential."
Scientific Background and Expertise
Dr. Heeger holds an MD and Master of Healthcare Management from the University of Heidelberg, Germany, a world-leading institution for research in nuclear medicine and targeted radionuclide therapies. He trained as a clinical oncologist at the University Hospital Heidelberg and the German Cancer Research Center, authoring more than 20 peer-reviewed publications across oncology and radiopharmaceutical research.
His scientific roots include early work in alpha-radiotherapy, including published research involving alpha-radioimmunotherapy using antibody conjugates in hematologic malignancies (search). Actinium holds approximately 250 patents and patent applications, including intellectual property related to cyclotron-based production of Ac-225.