Search

BACKGROUND: 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. Hot topics cover the entire scope of EJNMMI Radiopharmacy and Chemistry, demonstrating the progress in the research field in many aspects.

There is limited information on utilizing commercially supplied [18F]Fluoride from an off-site cyclotron for the synthesis of radiopharmaceuticals. This study explored the production of the PET hypoxia marker [18F]FMISO, using the Scintomics® GRP module and distantly produced [18F]Fluoride, which lacks published data. A radiochemical yield of 27.4 ± 3.6% (n = 5) and high radiochemical purity were achieved in synthesis time of 48 min. The [18F]FMISO met all Ph. Eur. standards, demonstrating the consistency and reliability of the module in generating a clinical-grade radiopharmaceutical using off-site produced [18F]Fluoride, but available patient doses were severely limited. [ABSTRACT FROM AUTHOR]

The labeling of peptides with gallium‐68 is often initially performed by manual labeling, but with high clinical demand, other alternatives are needed. Cold‐kits or automated synthesis are viable options for standardized methods and deemed pharmaceutically more acceptable. This study compares these [68Ga]Ga‐PSMA‐11 production methods. Data from 40 kit‐based and 40 automated syntheses of [68Ga]Ga‐PSMA‐11 were analyzed. Pre‐set criteria were evaluated including radiochemical purity, radionuclidic purity, chemical purity, physiological acceptability and sterility. The operator time and radiation dose received were measured. The robustness and repeatability of each method were assessed and a comparison of the running costs of each method is also provided. For both the methods all the analyzed products met the release criteria. No differences were found in radiochemical purity, radiochemical identity, radionuclidic purity, and sterility. However, radiochemical yield and apparent molar activity showed significant differences. For both methods, whole body radiation exposure to operators was lower than with manual labeling (25 – 40 μSv). The exposure during kit‐based labeling (14.5 ± μSv) was seven times higher than that of automated synthesis (2.05 ± 0.99 μSv). The automated synthesis was the more expensive method. Both methods are sound alternatives to manual synthesis and offer higher quality, better radiation protection and a more reliable manufacturing of radiopharmaceuticals. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to optimize a radiolabeling method using cationic processed Ga-68 eluates from a SnO2-based 68Ge/68Ga generator, followed by the development of DOTA-Tyr3-Thre8-octreotide (DOTATATE) kits.Procedures: Diluted generator eluates were adsorbed on a SCX resin and desorbed with acidified 5 M NaCl solution. Optimized labeling conditions were determined by variation of pH, using 35 μg DOTATATE and sodium acetate buffer. DOTATATE kits were developed based on optimized radiolabeling conditions, were labeled, and evaluated.Results: Optimized labeling conditions resulted in a radiolabeling efficiency of around 99 % and radiochemical yield of almost 85 %. Different kit preparation methods did not significantly influence the radiolabeling results. Kits were found to be stable over 3 months.Conclusion: A labeling method using SCX-processed Ga-68 eluates was optimized. DOTATATE kits specifically for these SCX-processed Ga-68 eluates were successfully formulated. A post-labeling Sep-Pak C18 purification should be optional. [ABSTRACT FROM AUTHOR]

Purpose: This study was aimed to develop single vial 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-peptide kits to be used with fractionated eluates from a SnO2-based 68Ge/68Ga generator.Procedures: Kits were formulated with 35 μg DOTA-Tyr3-Thre8-octreotide, DOTA-[Tyr3]-octreotide and DOTA-[NaI3]-octreotide (DOTATATE, DOTATOC and DOTANOC) and sodium acetate powder, vacuum-dried and stored at -20 °C for up to 12 months. Labelling of the kits was carried out with 2 ml 68Ga eluate. Comparative labelling was carried out using aqueous DOTA-peptide stock solutions kept frozen at -20 °C for up to 12 months.Results: The quality of the kits was found to be suitable over a 1-year storage period (pH, sterility, endotoxin content, radiolabelling efficiency and radiochemical yields of 68Ga-labelled DOTA-peptides). Radiochemical yields ranged from 73 to 83 %, while those obtained from stock solutions from 64 to 79 %. No significant decline in kit labelling yields was observed over a 12-month storage period.Conclusion: The single vial kit formulations met the quality release specifications for human administration and appear to be highly advantageous over using peptide stock solutions in terms of stability and user-friendliness. [ABSTRACT FROM AUTHOR]

Infective endocarditis is an important disease in developing countries. A combination of clinical findings, typical organisms cultured from blood, and specific echocardiographic features are used to establish the diagnosis. The diagnosis is often difficult because cultures are not always positive and transthoracic echocardiography lacks sensitivity and specificity, leading to delayed treatment or inappropriate therapy. As (99m)Tc-HMPAO-labeled leucocyte scintigraphy is used routinely to evaluate patients with suspected infectious processes, it was postulated that this technique might also aid in the diagnosis of infective endocarditis in patients with underlying chronic rheumatic heart disease or other valvular disease. Six patients were referred for (99m)Tc-HMPAO-labeled leucocyte scintigraphy. The white blood cells were labeled according to standard procedures. Whole-body planar imaging and single photon emission tomography of the chest area, with imaging at 30 minutes, 3 hours and 24 hours after the administration of the labeled leucocytes, were performed on all patients. All the scintigrams were negative. The reasons for the negative findings are not entirely clear, but probably reflect the pathological nature of vegetations, which consist mainly of masses of fibrin, clotted platelets and blood cell debris, containing the causative organisms. Leucocytes do not play a major role in the pathological process. Although only six patients were studied, it appears that (99m)Tc-HMPAO leucocyte scintigraphy is of little value in the evaluation of patients with infective endocarditis. A study after the administration of radiolabelled antibiotics may be of greater value and should be considered in these patients.