Talabostat mesylate is primarily investigated for its potential in cancer therapy due to its ability to modulate the immune system. It functions as an inhibitor of dipeptidyl peptidase enzymes, particularly DPPIV and FAP, which are involved in tumor microenvironment regulation. By inhibiting these enzymes, talabostat mesylate may help reduce tumor growth and metastasis in certain cancers. It has been studied in clinical trials for advanced solid tumors, including melanoma and non-small cell lung cancer, often in combination with other immunotherapies. The compound aims to enhance anti-tumor immune responses by altering peptide signaling and improving T-cell activation. Additionally, talabostat mesylate has shown potential in fibrotic diseases due to its effect on fibroblast activation protein, which plays a role in tissue remodeling and fibrosis. However, clinical development has faced challenges due to limited efficacy and toxicity concerns in later-stage trials.