Luca Palmieri1, Filipe Elvas1, Christel Vangestel1, Koon Pak2, Brian Gray2, Sigrid Stroobants1, Steven Staelens3, Leonie Wyffels4. 1. Molecular Imaging Center Antwerp, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, B-2610 Wilrijk, Belgium; Antwerp University Hospital, Department of Nuclear Medicine, Wilrijkstraat 10, B-2650, Edegem, Belgium. 2. Molecular Targeting Technologies, Inc., West Chester, PA, USA. 3. Molecular Imaging Center Antwerp, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, B-2610 Wilrijk, Belgium. 4. Molecular Imaging Center Antwerp, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, B-2610 Wilrijk, Belgium; Antwerp University Hospital, Department of Nuclear Medicine, Wilrijkstraat 10, B-2650, Edegem, Belgium. Electronic address: leonie.wyffels@uza.be.
Abstract
INTRODUCTION: [99mTc]duramycin is a SPECT tracer for cell death imaging. We evaluated the impact of kit formulation, purification and species difference on the pharmacokinetic profile and cell death targeting properties of [99mTc]duramycin in order to define the optimal conditions for (pre-)clinical use. METHODS: Three kits were prepared (A: traditional formulation, B: containing 1/3 of ingredients, C: containing HYNIC-PEG12-duramycin). Following labeling, the kits were used without purification, or with SPE or HPLC purification. The pharmacokinetic profile was evaluated in mice and rats at 24 h post tracer injection (p.i.). Non-specific accumulation of [99mTc]duramcyin was studied by μSPECT imaging in chemotherapy treated COLO205 tumor bearing mice pre-treated with cold duramycin (0.01-50 μg). Cell death targeting ability of the kits displaying the best pharmacokinetic profile was compared in a treatment response study in COLO205 tumor bearing mice treated with conatumumab (anti-DR5 antibody). RESULTS: HPLC purification of kit prepared [99mTc]duramycin and reducing the amount of kit ingredients resulted in the best pharmacokinetic profile with low accumulation in liver, spleen and kidneys. The use of PEGylated [99mTc]duramycin required longer circulation times (> 4 h pi) to obtain good imaging characteristics. Pre-treatment with duramycin significantly decreased tracer uptake in chemotherapy treated tumors in a dose-dependent manner. A blocking dose of 50 μg significantly increased non-specific accumulation in liver and spleen. Non-specific accumulation of [99mTc]duramycin was however demonstrated to be species dependent. HPLC purified kit A (5.21±1.71 %ID/cc) and non-purified kit B (1.68±0.46 %ID/cc) demonstrated a significant increase in tumor uptake compared to baseline following conatumumab treatment. CONCLUSIONS: To obtain [99mTc]duramycin with favorable imaging characteristics for cell death imaging in mice [99mTc]duramycin needs to be prepared with high specific activity by applying HPLC purification. The need for HPLC purification appears to be a species dependent phenomenon and might therefore not be required for clinical translation.
INTRODUCTION: [99mTc]duramycin is a SPECT tracer for cell death imaging. We evaluated the impact of kit formulation, purification and species difference on the pharmacokinetic profile and cell death targeting properties of [99mTc]duramycin in order to define the optimal conditions for (pre-)clinical use. METHODS: Three kits were prepared (A: traditional formulation, B: containing 1/3 of ingredients, C: containing HYNIC-PEG12-duramycin). Following labeling, the kits were used without purification, or with SPE or HPLC purification. The pharmacokinetic profile was evaluated in mice and rats at 24 h post tracer injection (p.i.). Non-specific accumulation of [99mTc]duramcyin was studied by μSPECT imaging in chemotherapy treated COLO205 tumor bearing mice pre-treated with cold duramycin (0.01-50 μg). Cell death targeting ability of the kits displaying the best pharmacokinetic profile was compared in a treatment response study in COLO205 tumor bearing mice treated with conatumumab (anti-DR5 antibody). RESULTS: HPLC purification of kit prepared [99mTc]duramycin and reducing the amount of kit ingredients resulted in the best pharmacokinetic profile with low accumulation in liver, spleen and kidneys. The use of PEGylated [99mTc]duramycin required longer circulation times (> 4 h pi) to obtain good imaging characteristics. Pre-treatment with duramycin significantly decreased tracer uptake in chemotherapy treated tumors in a dose-dependent manner. A blocking dose of 50 μg significantly increased non-specific accumulation in liver and spleen. Non-specific accumulation of [99mTc]duramycin was however demonstrated to be species dependent. HPLC purified kit A (5.21±1.71 %ID/cc) and non-purified kit B (1.68±0.46 %ID/cc) demonstrated a significant increase in tumor uptake compared to baseline following conatumumab treatment. CONCLUSIONS: To obtain [99mTc]duramycin with favorable imaging characteristics for cell death imaging in mice [99mTc]duramycin needs to be prepared with high specific activity by applying HPLC purification. The need for HPLC purification appears to be a species dependent phenomenon and might therefore not be required for clinical translation.
Authors: Hannah E Greenwood; Patrick N McCormick; Thibault Gendron; Matthias Glaser; Raul Pereira; Oliver D K Maddocks; Kerstin Sander; Tong Zhang; Norman Koglin; Mark F Lythgoe; Erik Årstad; Daniel Hochhauser; Timothy H Witney Journal: Clin Cancer Res Date: 2019-01-16 Impact factor: 12.531
Authors: Eliana Mc Tacconi; Sophie Badie; Giuliana De Gregoriis; Timo Reisländer; Xianning Lai; Manuela Porru; Cecilia Folio; John Moore; Arnaud Kopp; Júlia Baguña Torres; Deborah Sneddon; Marcus Green; Simon Dedic; Jonathan W Lee; Ankita Sati Batra; Oscar M Rueda; Alejandra Bruna; Carlo Leonetti; Carlos Caldas; Bart Cornelissen; Laurent Brino; Anderson Ryan; Annamaria Biroccio; Madalena Tarsounas Journal: EMBO Mol Med Date: 2019-05-24 Impact factor: 12.137