Lymph node dissection is a therapeutic option for prostate cancer patients with a high risk of- or proven lymph node metastases. Radioguided surgery after intravenous injection of [99mTc]Tc-PSMA could improve the selectivity of lymph node dissection. The aim of this project was to develop an automated synthesis method for [99mTc]Tc-PSMA, using the disposables and chemicals used at our institute for [68Ga]Ga-PSMA labeling. Furthermore, quality control procedures and validation results of the automated production of [99mTc]Tc-PSMA conform cGMP and cGRPP are presented.
[99mTc]Tc-PSMA is produced fully automatic with a Scintomics synthesis module. Quality control procedures are described and performed for: activity, labeling yield, visual inspection, pH measurement, sterility and endotoxin determination, radionuclide purity, radiochemical purity (99mTc-colloids, unbound [99mTc]pertechnetate, and other impurities), and HEPES content. Three batches of [99mTc]Tc-PSMA were prepared on three separate days for validation and stability testing at 0, 4, 6, and 24 h.
[99mTc]Tc-PSMA can be successfully manufactured automatically within a [68Ga]Ga-PSMA workflow with the addition of only [99mTc]pertechnetate and stannous chloride. The radiochemical purity after production was highly reproducible (96.3%, 97.6%, and 98.2%) and remained > 90% (required for patient administration) up to 6 h later.
A fully automated labeling procedure with corresponding quality control methods for production of [99mTc]Tc-PSMA is presented, which is validated according to cGMP and cGRPP guidelines and can be implemented in a GMP environment. The produced [99mTc]Tc-PSMA is stable for up to 6 h. The presented procedure is almost identical to the automated production of [68Ga]Ga-PSMA and can therefore be implemented expediently if a workflow for [68Ga]Ga-PSMA is already in place.
EJNMMI radiopharmacy and chemistry. 2020 May 01*** epublish ***
Else A Aalbersberg, Lotte van Andel, Martine M Geluk-Jonker, Jos H Beijnen, Marcel P M Stokkel, Jeroen J M A Hendrikx
Department of Nuclear Medicine, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, the Netherlands. ., Department of Nuclear Medicine, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, the Netherlands., Department of Pharmacy & Pharmacology, Netherlands Cancer Institute, Amsterdam, the Netherlands.