This is a multi-center, open-label extension (OLE) study of up to 60 participants with FCS rolling-over from Study ISIS 678354-CS3 (NCT04568434). Participants will receive olezarsen during a 53-week treatment period, followed by a 13-week post-treatment follow-up period. The length of participation in this study is approximately 70 weeks, which includes an up to 31-day qualification period, a 53-week treatment period, and a 13-week post-treatment evaluation period.
The purpose of this study is to evaluate the effect of olezarsen (formerly known as AKCEA-APOCIII-LRx) on the percent change in fasting triglycerides (TG) from baseline.