A Study of Olezarsen (Formerly Known as AKCEA-APOCIII-LRX) Administered to Adults With Familial Chylomicronemia Syndrome (FCS) Previously Treated With Volanesorsen

Inclusion Criteria

• •1. Participants with FCS (clinical or genetic diagnosis) currently on or previously treated with volanesorsen (ISIS 304801)
• •o Study participants in countries where Waylivra® is commercially approved and available for participants should not be deprived of the treatment option with Waylivra®. Participation in this study for such participants will only be allowed when Waylivra® was discontinued due to AEs
• •2. The following concomitant medications will be allowed if dosing regimen is expected to remain constant through the end of the study (occasional or intermittent use of over-the-counter (OTC) medications will be allowed at Investigator's discretion):
• •* Statins, omega-3 fatty acids (prescription and OTC), fibrates, or other lipid-lowering medications. Participants taking OTC omega-3 fatty acids should make every effort to remain on the same brand through the end of the study
• •* Antidiabetic medications
• •* Oral anticoagulants (e.g., dabigatran, rivaroxaban, or apixaban, and warfarin with regular clinical monitoring)
• •* Tamoxifen, estrogens or progestins