%0 Journal Article
%T Dosimetry and pharmacokinetics of [177Lu]Lu-satoreotide tetraxetan in patients with progressive neuroendocrine tumours.
%A Schürrle SB
%A Eberlein U
%A Ansquer C
%A Beauregard JM
%A Durand-Gasselin L
%A Grønbæk H
%A Haug A
%A Hicks RJ
%A Lenzo NP
%A Navalkissoor S
%A Nicolas GP
%A Pais B
%A Volteau M
%A Wild D
%A McEwan A
%A Lassmann M
%J Eur J Nucl Med Mol Imaging
%V 51
%N 8
%D 2024 Jul 26
%M 38528164
%F 10.057
%R 10.1007/s00259-024-06682-1
%X <B>OBJECTIVE: </B>To evaluate the dosimetry and pharmacokinetics of the novel radiolabelled somatostatin receptor antagonist [177Lu]Lu-satoreotide tetraxetan in patients with advanced neuroendocrine tumours (NETs).<BR><B>METHODS: </B>This study was part of a phase I/II trial of [177Lu]Lu-satoreotide tetraxetan, administered at a median cumulative activity of 13.0 GBq over three planned cycles (median activity/cycle: 4.5 GBq), in 40 patients with progressive NETs. Organ absorbed doses were monitored at each cycle using patient-specific dosimetry; the cumulative absorbed-dose limits were set at 23.0 Gy for the kidneys and 1.5 Gy for bone marrow. Absorbed dose coefficients (ADCs) were calculated using both patient-specific and model-based dosimetry for some patients.<BR><B>RESULTS: </B>In all evaluated organs, maximum [177Lu]Lu-satoreotide tetraxetan uptake was observed at the first imaging timepoint (4 h after injection), followed by an exponential decrease. Kidneys were the main route of elimination, with a cumulative excretion of 57-66% within 48 h following the first treatment cycle. At the first treatment cycle, [177Lu]Lu-satoreotide tetraxetan showed a median terminal blood half-life of 127 h and median ADCs of [177Lu]Lu-satoreotide tetraxetan were 5.0 Gy/GBq in tumours, 0.1 Gy/GBq in the bone marrow, 0.9 Gy/GBq in kidneys, 0.2 Gy/GBq in the liver and 0.8 Gy/GBq in the spleen. Using image-based dosimetry, the bone marrow and kidneys received median cumulative absorbed doses of 1.1 and 10.8 Gy, respectively, after three cycles.<BR><B>CONCLUSIONS: </B>[177Lu]Lu-satoreotide tetraxetan showed a favourable dosimetry profile, with high and prolonged tumour uptake, supporting its acceptable safety profile and promising efficacy.<BR><B>BACKGROUND: </B>NCT02592707. Registered October 30, 2015.