Evaluation of the 177mLu-concentration in in-house produced 177Lu-radiopharmaceuticals and commercially available Lutathera®

Matthias Balzer; Fleur Spiecker; Stephanie Bluemel; Holger Amthauer; Winfried Brenner; Sarah Spreckelmeyer

doi:10.1186/s41181-023-00222-2

Evaluation of the ^177mLu-concentration in in-house produced ¹⁷⁷Lu-radiopharmaceuticals and commercially available Lutathera^®

EJNMMI Radiopharm Chem. 2023 Nov 6;8(1):37. doi: 10.1186/s41181-023-00222-2.

Authors

Matthias Balzer¹, Fleur Spiecker¹, Stephanie Bluemel¹, Holger Amthauer¹, Winfried Brenner¹, Sarah Spreckelmeyer²

Affiliations

¹ Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Nuclear Medicine, Augustenburger Platz 1, Berlin, 13353, Germany.
² Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Nuclear Medicine, Augustenburger Platz 1, Berlin, 13353, Germany. sarah.spreckelmeyer@charite.de.

Abstract

Background: ¹⁷⁷Lu-radiopharmaceuticals can contain the metastable impurity [^177mLu]lutetium with a physical half-life of 160.4 days, in varying concentrations depending on the route of production of the radionuclidic precursor [¹⁷⁷Lu]lutetium. Due to the long half-life of [^177mLu]lutetium, difficulties with waste disposal or sterility testing could arise. Here, we analyzed several ¹⁷⁷Lu-samples of different origins and suppliers regarding their ^177mLu-concentration.

Results: All samples tested showed a ^177mLu-concentration in the range that was stated on the certificate of analysis from the supplier which is in accordance with the European Pharmacopoeia.

Conclusions: Although all ^177mLu-concentrations were in accordance with the European Pharmacopoeia, we need to take into account the respective national legislation regarding radioactivity release limits. With regard to the German legislation, several probes for sterility testing in external laboratories could not be released for transport due to the concentration of [^177mLu]lutetium. Moreover, waste water tanks should specifically be monitored for ^177mLu-concentration, when e.g. Lutathera^® is administered in the clinic.

Keywords: Long-lived; Lutetium-177 m; Metastable; Radionuclidic impurities; Radiopharmaceutical quality control; Waste management.