Lu-177-FAPI-04

¹⁷⁷Lu-FAPI-04 is the therapeutic analogue of the PET Imaging agent ⁶⁸Ga-FAPI-04 from the FAPI. It is a DOTA-coupled quinolone analogue radiotherapeutic based on a Fibroplast Activation Protein (FAP)-specific enzyme inhibitor (FAPI). The same molecule has already been labeled with ⁹⁰Y.

FAPIs targets cancer-associated fibroblasts (CAFs), yielding images with similar or better quality compared with ¹⁸F-FDG-PET/CT among patients with cancer. Besides cancer, FAPIs may also be used for benign diseases such as fibroses, Atherosclerosis, rheumatoid arthritis, sarcoidosis, etc.

First attempts to Label the best molecules developed within this family with therapeutic radionuclides have proven successful. ⁶⁸Ga-FAPI-04 was tested in two breast cancer patients and ⁹⁰Y-FAPI-04 was used in one patient. First preclinical data with ⁶⁴Cu-FAPI-04 and ²²⁵Ac-FAPI-04 generated in pancreatic xenograft mouse models were published in October 2019. Of 15 synthesized FAPIs, FAPI-04 was identified as the most promising Tracer for clinical applications. Phase I studies are under preparation.

Target/Mechanism: Fibroblasts

Leading Emitter: beta electrons (β^–)