AIMS: Per the package insert, pemafibrate was contraindicated for use in patients with severe renal impairment despite its biliary excretion. To validate this, we evaluated the pharmacokinetics and safety of pemafibrate for 12 weeks in patients with hypertriglyceridemia and renal impairment. METHODS: In this phase 4, multicenter, placebo-controlled, double-blind, parallel-group, comparative study, 21 patients were randomly assigned to pemafibrate 0.2 mg/day or placebo within Groups A (estimated glomerular filtration rate [eGFR] ＜30 mL/min/1.73m without hemodialysis; pemafibrate n=4; placebo, n=2), B (hemodialysis; pemafibrate, n=4; placebo, n=1), and C (eGFR ≥ 30 and ＜60 mL/min/1.73m without hemodialysis; pemafibrate, n=8; placebo, n=2) for 12 weeks. Area under the concentration vs time curve within the dosing interval (τ) (AUC) of pemafibrate was measured after 12-week administration. RESULTS: The AUC (geometric mean) of pemafibrate was 7.333 and 7.991 ng·h/mL in Groups A+B and C, respectively; in Groups A+B to C at 12 weeks, the geometric mean ratio of pemafibrate AUC was 0.92 (90% confidence interval [CI]: 0.62, 1.36). The upper limit of the 90% CI was ≤ 2.0 (predetermined criterion). There was no consistent trend in the AUC and maximum plasma concentration of pemafibrate with/without statin use. Renal impairment degree did not affect the incidence of adverse events. No safety concerns were observed. CONCLUSION: Pemafibrate repeated administration in patients with severe renal impairment did not increase pemafibrate exposure.