Thank to their particular pharmacokinetics, the use of small organic molecules can be a very promising alternative to macromolecular targeting biomolecules (i.e. antibodies, peptides…) for specific imaging of tumours.
View Article and Find Full Text PDFUnlabelled: Although peptide radionuclide therapy (PRRT) using a somatostatin analog (SSA) radiolabeled with a beta- emitter: [Lu]Lu-DOTATATE has shown a good clinical efficacy in neuroendocrine tumors (NETs), most of the patients only achieved tumoral stabilization and rare but severe long-term hematological toxicities have been reported. One of the promising options to improve PRRT is targeted alpha therapy. It is therefore essential to propose animal models that can mimic systemic spread disease, especially microscopic disease such as early stage of NET liver metastases to explore targeted alpha therapy.
View Article and Find Full Text PDF[ Ga]Ga-PentixaFor is a frequently used radiotracer to image the CXCR4/CXCL12 axis in various malignancies, infections, and cardiovascular diseases. To answer increasing clinical needs, an automatized synthesis process ensuring efficient and reproducible production and improving operator's radioprotection is needed. [ Ga]Ga-PentixaFor synthesis has been described on other synthesizers but not on the miniAiO.
View Article and Find Full Text PDFAlthough the concept of theranostics is neither new nor exclusive to nuclear medicine, it is a particularly promising approach for the future of nuclear oncology. This approach is based on the use of molecules targeting specific biomarkers in the tumour or its microenvironment, associated with optimal radionuclides which, depending on their emission properties, allow the combination of diagnosis by molecular imaging and targeted radionuclide therapy (TRT). Copper-64 has suitable decay properties (both β and β- decays) for PET imaging and potentially for TRT, making it both an imaging and therapy agent.
View Article and Find Full Text PDFThe development of diagnostic and therapeutic radiopharmaceuticals is an hot topic in nuclear medicine. Several radiolabeled antibodies are under development necessitating both biokinetic and dosimetry extrapolations for effective human translation. The validation of different animal-to-human dosimetry extrapolation methods still is an open issue.
View Article and Find Full Text PDFBackground: The Editorial Board of EJNMMI Radiopharmacy and Chemistry releases a biannual highlight commentary to update the readership on trends in the field of radiopharmaceutical development.
Main Body: This selection of highlights provides commentary on 21 different topics selected by each coauthoring Editorial Board member addressing a variety of aspects ranging from novel radiochemistry to first-in-human application of novel radiopharmaceuticals.
Conclusion: Trends in radiochemistry and radiopharmacy are highlighted.
Cyclam-picolinate chelators were functionalized click chemistry with an additional carboxyl group for subsequent bioconjugation to antibodies or for the modification of the overall charge of the corresponding Cu-radiocomplexes. The -aryl functionalization strategy developed here preserves the chemical properties of the radiocomplexes whilst deeply enhancing their applications within nuclear medicine.
View Article and Find Full Text PDFRadiopharmaceutical practices are divided into large-scale industrial manufacturing and small-scale "in-house" hospital radiopharmacy unit. The recent evolution of nuclear medicine involves deep consequences in this ever-present regulatory state, and hospital radiopharmacy units cannot be considered as contract manufacturing organizations (CMO). This review provides an updated status report of the official (and non-official) guidelines supporting the regulations required to meet hospital and industry common radiopharmaceutical manufacturing standards to facilitate the current and future innovative radiopharmaceutical development.
View Article and Find Full Text PDF1C1m-Fc, a promising anti-TEM-1 DOTA conjugate, was labeled with Cu to target cancer cells for PET imaging and predicting the efficacy and safety of a previously studied [Lu]Lu-1C1m-Fc companion therapy. DOTA-conjugated 1C1m-Fc was characterized by mass spectrometry, thin layer chromatography and immunoreactivity assessment. PET/CT and biodistribution studies were performed in human neuroblastoma xenografted mice.
View Article and Find Full Text PDFBackground: The Editorial Board of EJNMMI Radiopharmacy and Chemistry releases a biyearly highlight commentary to update the readership on trends in the field of radiopharmaceutical development.
Results: This commentary of highlights has resulted in 21 different topics selected by each member of the Editorial Board addressing a variety of aspects ranging from novel radiochemistry to first in man application of novel radiopharmaceuticals. Also the first contribution in relation to MRI-agents is included.
Purpose: The coronavirus disease 2019 (COVID-19) pandemic reshaped the usual risk: benefit equilibrium that became a trade-off between the infection exposure risk for the patient (and for staff) and the risk associated with delaying or cancelling the nuclear medicine examination. This study aimed at quantifying the impact of the first COVID-19 lockdown in France on nuclear medicine examination volume together with volume of examination cancellation and non-attendance.
Methods: We retrospectively assessed the volume of planned examinations from 1 month before to 1 month after the first lockdown in French high-volume nuclear medicine departments (NMD) sharing the same information management system including both university hospitals, UH (n = 7), and cancer centres, CC (n = 2).
Chem Sci
November 2020
Easy access to radioiodinated and At-labelled bio(macro)molecules is essential to develop new strategies in nuclear imaging and targeted radionuclide therapy of cancers. Yet, the labelling of complex molecules with heavy radiohalogens is often poorly effective due to the multiple steps and intermediate purifications needed. Herein, we investigate the potential of arylboron chemistry as an alternative approach for the late stage labelling of antibodies.
View Article and Find Full Text PDFPretargeting parameters for the use of anti-carcinoembryonic antigen (CEA) bispecific monoclonal antibody TF2 and the Ga-labeled IMP288 peptide for immuno-PET have been optimized in a first-in-humans study performed on medullary thyroid carcinoma (MTC) patients (the iPET-MTC study). The aim of this post hoc analysis was to determine the sensitivity of immuno-PET in relapsing MTC patients, in comparison with conventional imaging and F-l-dihydroxyphenylalanine (F-DOPA) PET/CT. Twenty-five studies were analyzed in 22 patients.
View Article and Find Full Text PDFHerein we present the preparation of two novel cyclam-based macrocycles ( and ), bearing phosphonate-appended pyridine side arms for the coordination of copper(II) ions in the context of Cu PET imaging. The two ligands have been prepared through conventional protection-alkylation sequences on cyclam, and their coordination properties have been thoroughly investigated. The corresponding copper complexes have been fully characterized in the solid state (X-ray diffraction analysis) and in solution (EPR and UV-vis spectroscopies).
View Article and Find Full Text PDF1C1m-Fc, an anti-tumor endothelial marker 1 (TEM-1) scFv-Fc fusion protein antibody, was previously successfully radiolabeled with Lu. TEM-1 specific tumor uptake was observed together with a non-saturation dependent liver uptake that could be related to the number of dodecane tetraacetic acid (DOTA) chelator per 1C1m-Fc. The objective of this study was to verify this hypothesis and to find the best DOTA per 1C1m-Fc ratio for theranostic applications.
View Article and Find Full Text PDFPurpose: The aim of this study was to compare retrospectively 18F-DOPA PET/CT versus 68Ga-DOTANOC PET/CT in a group of patients affected by midgut NET.
Patients And Methods: Patients with histologically proven grade 1 or grade 2 midgut NET were explored after injection of 150 MBq of 68Ga-DOTANOC and 210 MBq of 18F-DOPA. The PET/CTs were analyzed visually and semiquantitatively at the patient level, regional level (7 defined regions), and lesion level (maximum of 5 lesions/organ).
Whilst radiopharmaceuticals have an important role to play in both imaging and treatment of patients, most notably cancer patients, nuclear medicine and radiopharmacy are currently facing challenges to create innovative new drugs. Traditional radiopharmaceutical manufacture can be considered as either a routine hospital production or a large-scale industrial production. The gap between these two practices has meant that there is an inability to supply innovative radiopharmaceuticals for use at the local level for mono- or multicentric clinical trials with satisfactory quality and safety specifications.
View Article and Find Full Text PDFThis prospective study evaluated the imaging performance of a novel pretargeting immunologic PET (immuno-PET) method in patients with human epidermal growth factor receptor 2 (HER2)-negative, carcinoembryonic antigen (CEA)-positive metastatic breast cancer, compared with CT, bone MRI, and F-FDG PET. Twenty-three patients underwent whole-body immuno-PET after injection of 150 MBq of Ga-IMP288, a histamine-succinyl-glycine peptide given after initial targeting of a trivalent anti-CEA, bispecific, antipeptide antibody. The gold standards were histology and imaging follow-up.
View Article and Find Full Text PDFThe impressive development of cancer immunotherapy in the last few years originates from a more precise understanding of control mechanisms in the immune system leading to the discovery of new targets and new therapeutic tools. Since different stages of disease progression elicit different local and systemic inflammatory responses, the ability to longitudinally interrogate the migration and expansion of immune cells throughout the whole body will greatly facilitate disease characterization and guide selection of appropriate treatment regiments. While using radiolabeled white blood cells to detect inflammatory lesions has been a classical nuclear medicine technique for years, new non-invasive methods for monitoring the distribution and migration of biologically active cells in living organisms have emerged.
View Article and Find Full Text PDFBased on our previous works involving two 1,4,7-triazacyclononane (tacn)-based ligands Hno2py1pa (1-Picolinic acid-4,7-bis(pyridin-2-ylmethyl)-1,4,7-triazacyclononane) and Hno1pa (1-Picolinic acid-1,4,7-triazacyclononane), we report here the synthesis of analogues bearing picolinate-based π-conjugated ILCT (Intra-Ligand Charge Transfer) transition antenna (HL1, HL2), using regiospecific N-functionalization of the tacn skeleton and their related transition metal complexes (e.g. Cu, Zn and Mn).
View Article and Find Full Text PDFBioconjug Chem
September 2019
Following the successful synthesis of a -functionalized version of the TE1PA ligand, a monopicolinate cyclam, we looked to demonstrate its in vivo properties versus DOTA and NOTA, after conjugation on the 9E7.4 rat antibody, an IgG against CD138 murine, which has relevant properties for multiple myeloma targeting. For each ligand, different conjugation approaches had been considered to select the most appropriate for the comparative study.
View Article and Find Full Text PDFMonoclonal antibody (mAb)-based therapies have experienced considerable growth in cancer management. When labeled with radionuclides, mAbs also represent promising probes for imaging or theranostic approaches. Initially, mAbs have been radiolabeled with single-photon emitters, such as I, Tc, or In, for diagnostic purposes or to improve radioimmunotherapy (RIT) using dosimetry estimations.
View Article and Find Full Text PDFAlthough positron emission tomography (PET) imaging with 18-Fluorodeoxyglucose (F-FDG) is a promising technique in multiple myeloma (MM), the development of other radiopharmaceuticals seems relevant. CD138 is currently used as a standard marker for the identification of myeloma cells and could be used in phenotype tumor imaging. In this study, we used an anti-CD138 murine antibody (9E7.
View Article and Find Full Text PDFPurpose: The aim of this study was to compare the performances pretargeted immunoPET Ga-PETimaging (Ga-pPET) with anti carcino-embryonic antigen (CEA) and anti-histamine-succinyl-glycine (HSG) recombinant humanized bispecific monoclonal antibody (TF2) and Ga-labeled HSG peptide (IMP288) to conventional FDG-PET in an orthotopic murine model of liver metastases of human colonic cancer.
Methods: Hepatic tumor burden following intra-portal injection of luciferase-transfected LS174T cells in nude mice was confirmed using bioluminescence. One group of animals was injected intravenously with TF2 and with Ga-IMP288 24 hours later (n=8).
In view of the excellent copper(ii) and 64-copper(ii) complexation of a TE1PA ligand, a monopicolinate cyclam, in both aqueous medium and in vivo, we looked for a way to make it bifunctional, while maintaining its chelating properties. Overcoming the already known drawback of grafting via its carboxyl group, which is essential to the overall properties of the ligand, a TE1PA bifunctional derivative bearing an additional isothiocyanate coupling function on a carbon atom of the macrocyclic ring was synthesized. This led to an architecture that is comparable to that of other commercially available bifunctional copper(ii) chelators such as p-SCN-Bn-DOTA already used in clinical trials for 64Cu-immuno-PET imaging.
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