EANM guideline for harmonisation on molar activity or specific activity of radiopharmaceuticals: impact on safety and imaging quality

This guideline on molar activity (A(m)) and specific activity (A(s)) focusses on small molecules, peptides and macromolecules radiolabelled for diagnostic and therapeutic applications. In this guideline we describe the definition of A(m) and A(s), and how these measurements must be standardised and harmonised. Selected examples highlighting the importance of A(m) and A(s) in imaging studies of saturable binding sites will be given, and the necessity of using appropriate materials and equipment will be discussed. Furthermore, common A(m) pitfalls and remedies are described. Finally, some aspects of A(m) in relation the emergence of a new generation of highly sensitive PET scanners will be discussed.

Automated summary

This guideline focuses on the molar activity and specific activity of radiolabelled small molecules, peptides, and macromolecules for diagnostic and therapeutic applications. It describes the standardisation and harmonisation of these measurements, discusses the importance of A(m) and A(s) in imaging studies of saturable binding sites, and highlights the necessity of using appropriate materials and equipment. Additionally, common pitfalls and remedies in molar activity are described, along with considerations related to the emergence of highly sensitive PET scanners.