Tipiracil (TPI) is a potent and competitive inhibitor of thymidine phosphorylase (TPase) with an IC50 value of 35 nM for human placental TPase. It is selective for TPase over other pyrimidine-metabolizing enzymes (IC50s = >1 mM for UPase, OPRTase, TK, and DPDase). TPI inhibits the phosphorolysis and degradation of trifluorothymidine , a cytotoxic nucleoside, in human breast and colon carcinoma tumor samples. Oral administration of TPI (12.5-50 mg/kg) enhances the anti-tumor activity of trifluorothymidine in a mouse AZ-521 stomach cancer xenograft model. Formulations containing TPI have been used for the treatment of metastatic colorectal cancer.
Tipiracil Hydrochloride serves as a treatment for metastatic colorectal cancer (mCRC). A thymidine phosphorylase inhibitor.
ChEBI: Tipiracil hydrochloride is a hydrochloride obtained by combining tipiracil with one equivalent of hydrochloric acid. Used in combination with trifluridine, a nucleoside metabolic inhibitor, for treatment of advanced/relapsed unresectable colorectal cancer. It has a role as an antineoplastic agent and an EC 2.4.2.4 (thymidine phosphorylase) inhibitor. It is a hydrochloride and an iminium salt. It contains a tipiracil(1+).
Tipiracil is an inhibitor of thymidine phosphorylase. Tipiracil is used in combination with trifluridine as TAS-102 for the treatment of refractory metastatic colorectal cancer. Tipiracil increases the bioavailability of trifluridine by blocking the enzyme that would otherwise protect the tumors by metabolizing trifluridine.
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