• Fasting TG ≥ 10 mmol/L (≥ 880 mg/dL) at screening refractory to standard lipid lowering therapy

• Diagnosis of FCS

• Willing to follow dietary counseling as per investigator judgement based on local standard of care

• Participants of childbearing potential (males & females) must use highly-effective contraception during the study and for at least 24 weeks following the last dose of study medication. Males must not donate sperm during the study and for at least 24 weeks following the last dose of study medication

• Women of childbearing potential must have a negative pregnancy test at Screening and cannot be breastfeeding

• Women of childbearing potential on hormonal contraceptives must be stable on the medication for ≥ 2 menstrual cycles prior to Day 1