Purpose: Residual cardiovascular risk reduction by fenofibrate in patients with high serum triglyceride (TG) levels despite previous statin monotherapy is not well characterized. The purpose of this study was to evaluate the efficacy and safety of a combination of choline fenofibrate and statin in patients with inadequately controlled TG levels despite previous statin monotherapy.Methods: This prospective, multicenter, randomized, double-blind study was conducted in Korea. A total of 133 patients with controlled LDL-C but elevated TG levels, already receiving statin monotherapy, were enrolled in the study, which was conducted from July 2018 to December 2019. Patients were randomly assigned to receive combination therapy with choline fenofibrate and statin or statin monotherapy in a 1:1 ratio. After 8 weeks of treatment, the lipid profiles and safety parameters of the patients in the 2 groups were compared.Findings: The study included 127 patients (64 in the combination group and 63 in the control group) older than 19 years. After 8 weeks of therapy, mean serum TG levels significantly decreased from 269.8 to 145.5 mg/dL ( P < 0.0001) in the combination therapy group, whereas no significant changes occurred in the statin monotherapy group (from 271.1 to 280.5 mg/dL). Contrarily, the mean serum HDLC levels significantly increased from 45.0 to 50.4 mg/dL ( P = 0.0004) in the combination therapy group, whereas there were no significant changes in the monotherapy group (from 44.3 to 44.7 mg/dL). There were no additional serious adverse events in the combination therapy group compared with the statin monotherapy group.Implications: The combination therapy using choline fenofibrate and statin was found to be effective in serum TG control and likely tolerable in patients with high TG levels despite statin monotherapy. A