SAR-monoFAP

SAR-monoFAP is a radiopharmaceutical agent designed as a monomeric fibroblast activation protein (FAP) antagonist, developed by Clarity Pharmaceuticals. It is intended for use in both diagnostic imaging and potential targeted radiotherapy of cancers that express FAP, which is highly upregulated in cancer-associated fibroblasts across many tumor types. The compound can be labeled with copper radioisotopes—copper-64 (^64Cu) for positron emission tomography (PET) imaging and copper-67 (^67Cu) for therapeutic applications. Preclinical studies have demonstrated its ability to target FAP-expressing tumors, though uptake and retention are lower compared to the dimeric version (SAR-bisFAP). As of June 2025, SAR-monoFAP remains an investigational product without regulatory approval; its safety and efficacy have not been established in humans[1][4][6][9].