To investigate the efficacy and safety of K-877 Extended Release (ER) 0.2 mg/day or 0.4 mg/day (once daily) for 12 weeks in dyslipidemia, using K-877 Immediate Release (IR) 0.2 mg/day (twice daily) as a control.

Inclusion Criteria:

1. Patients with dyslipidemia had to be age 20 years or older at written informed consent
2. Patients who have received dietary or exercise guidance from 12 weeks or more prior to Screening
3. Patients with the fasting serum TG >= 200 mg/dL twice consecutively at Screening

Exclusion Criteria:

1. Patients with a fasting serum TG > 1000 mg/dL at Screening
2. Patients who require administration of prohibited drugs during the clinical trial period after written informed consent
3. Patients with uncontrolled thyroid disease
4. Patients with type 1 diabetes and uncontrolled diabetes [HbA1c(NGSP) >= 8.0 % at Screening]
5. Patients with uncontrolled hypertension (SBP >= 160 mmHg or DBP >= 100 mmHg)
6. Patients with an AST or ALT three times the upper limit at Screening
7. Patients with an CK five times the upper limit at Screening
8. Patients with cirrhosis or those with biliary obstruction
9. Patients with acute myocardial infarction within 3 months before obtaining informed consent
10. Patients with heart failure class III or higher according to NYHA cardiac function classification
11. Patients with malignant tumor or those who are judged to have a high risk of recurrence
12. Patients with a history of serious drug allergies (anaphylactic shock, etc.)
13. Pregnant women, lactating women, women planning to become pregnant or lactating during the study period, or pregnant women who do not use specific contraceptive methods
14. Patients who have collected 400 mL or more of whole blood within 16 weeks, or 200 mL or more of whole blood within 4 weeks, or blood samples (plasma and platelet components) within 2 weeks before Screening
15. Patients who have received K-877 (pemafibrate)
16. Patients who participate in other clinical trials at the time of written informed consent and who received medication or who have received clinical trials other than placebo for less than 16 weeks
17. Patients who have been determined inappropriate by the investigator, etc