ECE2017 Eposter Presentations: Thyroid Thyroid (non-cancer) (260 abstracts)
1Jagiellonian University Medical College, Krakow, Poland; 2Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy; 3Innsbruck Medical University, Innsbruck, Austria; 4University Medical Centre Ljubljana, Ljubljana, Slovenia; 5Radioisotope Centre Polatom, NCBJ, Otwock, Poland; 6University Hospital Freiburg, Freiburg, Germany; 7Molecular Radiopharmacy, INRASTES, NCSR Demokritos, Athens, Greece; 8Erasmus MC, Rotterdam, The Netherlands; 9University Hospital, Krakow, Poland.
Effective targeted therapy for advanced endocrine malignancies is a goal of modern endocrinology. We herein present promising results of the first phase of clinical part of European project (Gran-T-MTC) aimed to assess the safety of gastrin analogue CP04 (DOTA-(DGlu)6-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2) i.v. administration in dose (50 μg) useful for translation to 177In-CP04 for PRRT. CP04 has been selected for MTC therapy based on a high CCK-2 receptor expression in MTC and superior pharmacokinetics properties among gastrin analogues tested. Positive results of preclinical part of the study confirmed possibility of 111In-CP04 applying in humans.
Aim: To assess 111In-CP04 safety, biodistribution and dosimetry.
Material and methods: Four patients: three with progressive/metastatic MEN2A-related MTC (18F-FDG-PET/MRI positivity), one with sporadic MTC (short calcitonin doubling time) were enrolled. Basal calcitonin levels ranged between 279 and 824 pg/ml.
Study design: During the first clinical trial phase each patient received 111In-CP04 (200 MBq) in 2 different doses: a low (10 μg) and high (50 μg). Biodistribution and dosimetry data were assessed based on serial planar and SPECT/CT images over time.
Results: No side effects were observed during injection of either CP04 dose. In all patients 111In-CP04 uptake was confirmed in MTC lesions regardless of peptide dose (in one patient uptake was low). The compound showed both a renal clearance and uptake in the stomach wall with subsequent intestinal clearance with for both peptide doses similar kinetics and little variation across patients. The Effective dose was 6 mSv/200 MBq, irrespective of the amount of peptide. The kidney absorbed dose for the 50 μg therapeutic amount of CP04 if labeled with 177Lu was estimated at 0.32Gy/GBq and the stomach absorbed dose at 0.13Gy/GBq.
Conclusions: MTC metastases can be detected with 111In-CP04. Biodistribution and dosimetry data show CP04 promising radiopharmaceutical for MTC therapy if labeled with 177Lu. The confirmatory second part of clinical phase of trial has just begun.