Novel terbium series application for diagnosis and therapy. (Photo: J. Vera Araujo/IAEA)
Theranostic radiopharmaceuticals, which combine diagnosis and therapy within a single administration, are transforming the management of cancer and other diseases.
The IAEA is inviting research organizations to participate in a new coordinated research project supporting the development and harmonization of production methods, radiolabelling strategies and quality control procedures for terbium radioisotopes, while strengthening technical capacity across participating institutions.
Theranostics represents an important pillar of modern oncology, enabling more accurate diagnosis and targeted treatment. Increasing global demand is placing pressure on health systems to ensure that these technologies are not only effective, but also scalable, accessible and cost‑efficient.
Despite rapid scientific advances, producing a reliable and sustainable supply of radionuclides and radiopharmaceuticals at scale remains a key challenge. Even for well-established isotopes, constraints related to production capacity, infrastructure and global distribution continue to limit availability. Addressing these challenges is essential for expanding equitable access to precision oncology solutions globally.
Why Terbium?
Terbium isotopes are receiving increasing attention due to their favourable decay properties and unique theranostic potential.
Terbium's key advantage is that it contains multiple isotopes that can be used for both imaging and therapy: terbium‑152 and terbium‑155 for imaging, and terbium‑161 and terbium‑149 for targeted radionuclide therapy.
This 'one element, multiple applications' approach supports the development of matched radiopharmaceutical pairs, enabling patient‑tailored diagnosis, treatment planning and therapy monitoring within a unified theranostic framework.
Terbium-161 has shown strong promise due to its emission of low-energy beta particles and Auger electrons, which may enhance therapeutic efficacy, especially for small lesions and disseminated disease. Despite this potential, the clinical and translational uptake of terbium-based radiopharmaceuticals remains at an early stage.
Major challenges include insufficient sustainable production routes, limited availability of enriched targets and the need for harmonized radiochemical processing and quality control approaches. Several countries also face capacity gaps in radionuclide production, radiochemistry and quality assurance. Without coordinated action to address these challenges, terbium‑based theranostic applications are unlikely to be developed or implemented at scale.
Laboratory work supporting the production and processing of radiopharmaceuticals for medical applications. (Photo: L. Gil Martinez / IAEA)
Research Objectives
The new IAEA Coordinated Research Project on Advanced Theranostics Using Terbium Radioisotope Series (Tb Series) will provide a platform for knowledge exchange and technology transfer among Member States.
Participating institutions will work to establish reliable methodologies for radionuclide production and radiopharmaceutical development, supporting safe and effective implementation in preclinical and early phase clinical settings. The initiative builds on existing IAEA efforts in theranostics and aims to facilitate the broader adoption of emerging radionuclides in nuclear medicine.
The project has four main objectives:
- Strengthen Member States' capacity for production and quality control of terbium radioisotopes.
- Develop and harmonize production and radiolabelling methodologies.
- Facilitate knowledge sharing and technology transfer among participating institutions.
- Support the translation of emerging terbium radionuclides into preclinical and clinical research to enable broader access to novel theranostic agents.
Through these activities, the project aims to deliver standardised and validated production protocols, enhance technical expertise, improve the availability of terbium radioisotopes for research and strengthen international collaboration and dissemination of best practices.
How to Join
Participation is open to IAEA Member States with demonstrated or emerging capabilities in radionuclide production, radiochemisty or radiopharmaceutical sciences.
Eligible institutions should have access to appropriate irradiation facilities, such as cyclotrons, research reactors or accelerator-based systems, or plans to collaborate with facilities capable of producing terbium radioisotopes.
Expertise in radiochemistry, radiolabelling, quality control or preclinical and clinical translation of theranostic radiopharmaceuticals is also welcome.
Research organizations wishing to participate are invited to submit their Proposal for Research Contract or Agreement by email no later than 31 July 2026 to the IAEA's Research Contracts Administration Section using the appropriate template on the Coordinated Research Activities web portal . The IAEA encourages applicant institutions to involve women and young researchers in their proposals.
