This is a Phase 3, multi-center, open-label safety study of up to 30 participants with FCS, previously treated with volanesorsen. The study consists of 3 periods: 1) Screening Period: Week -4 to Week -1 (up to 4 weeks); 2) Treatment Period up to Week 53; and 3) Post-Treatment Follow-up Period: Week 54 to Week 66 (13 weeks). Participants enrolled will receive olezarsen every 4 weeks during the 53-week Treatment Period.
The purpose of the study is to evaluate the safety, tolerability, pharmacokinetic (PK) and pharmacodynamic (PD) effects of olezarsen (formerly known as AKCEA -APOCIII-LRX) in participants with FCS previously treated with volanesorsen.