Studies on batch formulation of a freeze dried kit for the preparation of 99mTc-HYNIC-TATE for imaging neuroendocrine tumors

Abstract

Aim: To formulate freeze dried cold kits for preparation of ^99mTc-HYNIC-TATE suitable for use at hospital radiopharmacy and establish clinical utility of ^99mTc-HYNIC-TATE prepared using kits for detection of neuroendocrine tumors (NETs).

Methods: Standardization of reagent concentrations for formulation of freeze dried kits of HYNIC-TATE was carried out. Consistency in formulation was tested by six batch preparation. Quality control tests were carried out to establish compliance of specifications of purity and safety criteria for both kits and ^99mTc-HYNIC-TATE formulated using kits. Clinical utility of ^99mTc-HYNIC-TATE prepared using kits was demonstrated in patients with histopathologically confirmed well-differentiated NETs.

Results: Pharmaceutical grade HYNIC-TATE kits compliant with all the quality control criteria were formulated and successfully radiolabeled with ^99mTc. Radiopharmaceutical was successfully utilized for detection of NETs in patients and comparison with uptake of ^99mTc-HYNIC-TOC and ¹⁷⁷Lu-DOTA-TATE was made.

Conclusion: The formulated kits are robust and provide consistently high radiolabeling yields (> 95%) with ^99mTc in short time periods requiring no additional purification. Initial clinical trials demonstrate the utility of ^99mTc-HYNIC-TATE using formulated kits.

Keywords: (99m)Tc-HYNIC-Octreotate ((99m)Tc-HYNIC-TATE); Diagnostic imaging; Neuroendocrine tumors (NET); Somatostatin receptors.