A Study of Olezarsen (ISIS 678354) Administered to Participants With Severe Hypertriglyceridemia

Key Inclusion Criteria:

• Fasting TG ≥ 500 mg/dL (5.65 mmol/L) at Screening and Qualification

• Patients must be on lipid-lowering therapy that should adhere to standard of care (SOC) per local guidelines. Lipid-lowering medications should be optimized andstabilized for at least 4 weeks prior to Screening to minimize changes in thesemedications during the study.

Key Exclusion Criteria:

• Hemoglobin A1c (HbA1c) ≥ 9.5% at Screening

• Alanine aminotransferase or aspartate aminotransferase > 3.0 × upper limit of normal

• Total bilirubin > upper limit of normal unless due to Gilbert's syndrome

• Estimated GFR < 30 mL/min/1.73 m^2