Dual-Nuclide Radiopharmaceuticals for Positron Emission Tomography Based Dosimetry in Radiotherapy

Improvement of the accuracy of dosimetry in radionuclide therapy has the potential to enhance patient safety and therapeutic outcomes. Although positron emission tomography (PET) is ideally suited for acquisition of dosimetric data because PET is inherently quantitative and offers high sensitivity and spatial reso-lution, it is not directly applicable for this purpose since common therapeutic radionuclides lack the necessary positron emission. We report on synthesis of dual-nuclide labeled radiopharmaceuticals with therapeutic and PET functionality which are based on common and widely available metal radionuclides. Dual-chelator conjugates, featuring interlinked cyclen- and triazacy-clononane-based polyphosphinates DOTPI and TRAP, allow for strictly regioselective complexation of thera-peutic (e.g, 177LuIII or 213BiIII) and PET (particularly 68GaIII) radiometals in the same molecular framework by exploiting the orthogonal metal ion selectivity of these chelators (DOTPI: large cations, such as lanthanide(III) ions; TRAP: small trivalent ions, such as GaIII). Such DOTPI-TRAP conjugates were decorated with 3 Gly-urea-Lys (KuE) motifs for targeting prostate-specific membrane antigen (PSMA), employing Cu-catalyzed (CuAAC) as well as strain-promoted (SPAAC) click chemistry. These were labeled with 177Lu or 213Bi and 68Ga and used for in-vivo imaging of LNCaP (human prostate carcinoma) tumor xenografts in SCID mice by PET, thus proving practical applicability of the concept.

WURZER A;  SEIDL C.;  MORGENSTERN Alfred;  BRUCHERTSEIFER Frank;  SCHWAIGER Markus;  WESTER Hans-Jürgen;  NOTNI Johannes; 

2018-05-03

WILEY-V C H VERLAG GMBH

JRC106081

0947-6539,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC106081,   

10.1002/chem.201702335,