Citius, Altius, Fortius: An Olympian Dream for Theranostics

64Cu-SARTATE PET Imaging of Patients with Neuroendocrine Tumors Demonstrates High Tumor Uptake and Retention, Potentially Allowing Prospective Dosimetry for Peptide Receptor Radionuclide Therapy

“…There is increasing evidence that changing either the radionuclide or the chelating agent can alter the affinity of SSAs for somatostatin receptors (20). Accordingly, the performance of novel radiopharmaceuticals cannot be reliably predicted by the receptorbinding affinity of the peptide (21). Additionally, when a long-lived radioisotope is used, retention of activity at sites of disease is important both for diagnostic and for therapeutic purposes.…”

Peptide Receptor Radionuclide Therapy with 67Cu-CuSarTATE Is Highly Efficacious Against a Somatostatin-Positive Neuroendocrine Tumor Model

“…The use of a short-lived radionuclide (gallium-68, t1/2 = 68 minutes) to predict dosimetry for subsequent therapy with long-lived radionuclide lutetium-177 (t1/2 = 6.65 d, β -= 100%, Eβ -(mean) = 134 keV) introduces limitations in modelling dosimetry. Furthermore, the use of two different chemical elements (gallium and lutetium) with different chemistries can lead to inconsistent tissue biodistribution as it is likely that peptide-metal complex assemblies prepared with different metal ions do not have the same binding and internalization interactions and altered excretory pathways (6)(7)(8). Furthermore, the use of the same element for both imaging and therapy would represent an important advance for radionuclide therapy, particularly if the half-life of the diagnostic agent is sufficient to evaluate clearance kinetics from critical target organs.…”

Less Exploited GPCRs in Precision Medicine: Targets for Molecular Imaging and Theranostics

“…Within this context, G-protein-coupled receptors (GPCRs), apart from being intensively studied drug targets [29], have been also largely exploited as molecular targets for noninvasive imaging and/or systemic radiotherapy of various diseases. The most paradigmatic and clinically successful example is the use of somatostatin receptors (SSTRs)-targeted radiolabeled somatostatin analogs for imaging and peptide receptor radionuclide therapy of neuroendocrine tumors (NETs) [30]. A set of excellent reviews has surveyed the most relevant achievements in this field, namely SPECT and PET imaging [31,32,33,34,35,36,37,38,39], and radionuclide therapy [40,41], including theranostic applications [42,43].…”