Optimization of 177Lu-labelling of DOTA-TOC, PSMA-I&T and FAPI-46 for clinical application

Abstract

Background: (177)Lu-radiopharmaceuticals are routinely used for the treatment of various tumor entities. The productions of radiopharmaceuticals follow strict good-manufacturing practice guidelines and synthesis optimizations thereof have a strong impact on e.g. the quality of the product, radiation safety and costs. The purpose of this study is to optimize the precursor load of three radiopharmaceuticals. For that, different precursor loads were evaluated and compared to previously reported findings. Results: All three radiopharmaceuticals were successfully synthesized in high radiochemical purities and yields on the ML Eazy. The precursor load was optimized for [Lu-177]Lu-FAPI-46 from 27.0 to 9.7 mu g/GBq, for [Lu-177]Lu-DOTATOC from 11 to 10 mu g/GBq and for [Lu-177]Lu-PSMA-I&T from 16.3 to 11.6 mu g/GBq. Conclusions: We successfully reduced the precursor load for all three radiopharmaceuticals while maintaining their quality.