Urate transporter 1 (URAT1) is a well-known therapeutic target for reducing urate levels in the treatment of hyperuricemia and gout. However, current pharmacological studies have failed to evaluate the efficacy of URAT1 inhibitors in non-primate animal models. We established a human URAT1 (hURAT1) transgenic knock-in (KI) mouse model to assess uricosuric agents' effectiveness and characterize URAT1-caused pathogenesis.