Impact of Conversion from Conventional Pemafibrate to Novel Pemafibrate XR on Hypertriglyceridemia: An Observational Retrospective Study

<b>Background:</b> Pemafibrate is a novel selective peroxisome proliferator-activated receptor-α modulator, which was demonstrated to reduce serum triglyceride levels with few drug-related adverse events in several clinical studies, as well as phase II and III clinical trials. One of the limitations of this medicine was the requirement of twice-daily oral administration, resulting in reduced medication adherence, particularly in elderly patients, who are rather good targets for this medicine. Recently, a once-daily extended-release (XR) tablet has been introduced. Given an improvement in medication adherence, the therapeutic efficacy of pemafibrate may be enhanced. <b>Methods:</b> Patients with hypertriglyceridemia, in whom conventional twice-daily immediate-release (IR) pemafibrate was converted to pemafibrate XR between 2023 and 2024, were eligible. Each type of tablet was prescribed for three months, respectively. A dose change was not attempted. The serum triglyceride levels were compared between 3 months pre-conversion and 3 months post-conversion using a Friedman test and a post hoc Wilcoxon signed-rank test. <b>Results:</b> A total of 46 patients were included. The median age was 62 years, and 29 were men. IR was continued for 698 (280, 1183) days before the conversion. During the last 3-month IR therapy, serum triglyceride levels remained unchanged from 171 (138, 239) mg/dL to 181 (123, 245) mg/dL (<i>p</i> = 0.78). Following the conversion, no patients had drug-related adverse events, and all patients completed 3-month XR therapy. At three months after the conversion, the serum triglyceride levels decreased significantly from 181 (123, 245) mg/dL to 146 (107, 184) mg/dL (<i>p</i> < 0.001). <b>Conclusions:</b> Pemafibrate XR might be a more promising medication than conventional IR in improving hypertriglyceridemia, probably due to improved medication adherence.