A Phase 3 interventional study of Olezarsen in Familial Chylomicronemia Syndrome, sponsored by Ionis Pharmaceuticals, Inc.. Active, not recruiting at 27 sites in 11 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-12-12.
Sponsored by Ionis Pharmaceuticals, Inc. · Phase 3, Interventional, and Treatment
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.
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 157-week treatment period, followed by a 13-week post-treatment follow-up period. The length of participation in this study is approximately 201 weeks, which includes an up to 31-day qualification period, a 157-week treatment period, and a 13-week post-treatment evaluation period.
Treatment has been extended to obtain additional safety assessments and efficacy data and to provide patients with continued access to ISIS 678354 until the drug may be available commercially.
Ionis Pharmaceuticals, Inc. is the lead sponsor of 116 studies on the registry; 10 are open to participants now.
Of its 48 completed or terminated interventional studies of FDA-regulated products, 21 (44%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Olezarsen will be administered once every 4 weeks by subcutaneous (SC) injection from Week 1 through Week 153.
Drug: Olezarsen
Olezarsen will be administered by SC injection.
Also known as: ISIS 678354, AKCEA -APOCIII-LRx
Percent Change From Baseline in Fasting TG at 6 Months (Average of Weeks 23, 25, and 27) Compared to Baseline
Time frame: Baseline and 6 months
Percent Change From Baseline in Fasting TG at 12 Months (Average of Weeks 51 and 53) at 24 Months (Average of Week 103 and Week 105) and 36 Months (Average of Week 155 and Week 157)
Time frame: Baseline and 36 months
Percentage of Participants Who Achieve ≥ 40% Reduction in Fasting TG From Baseline at 6 Months
Time frame: At 6 months
Percentage of Participants Who Achieve ≥ 40% Reduction in Fasting TG From Baseline at 12, 24, 36 Months
Time frame: At 12, 24, 36 months
Percent Change in Fasting apoC-III from Baseline at Month 6
Time frame: Baseline and 6 months
Percent Change in Fasting apoC-III from Month 12, 24, 36
Time frame: At 12, 24, 36 months
Percent Change From Baseline in Fasting Apolipoprotein 48 (apoB48) at 6 Months
Time frame: At 6 months
Percent Change From Baseline in Fasting apoB48 at 12, 24, 36 Months
Time frame: At 12, 24, 36 months
Percent Change in Fasting non-HDL-C from Baseline at Month 6
Time frame: Baseline and 6 months
Percent Change in Fasting non-HDL-C from Months 12, 24, 36
Time frame: At 12, 24, 36 months
Percentage of Participants Who Achieve Fasting TG ≤ 880 milligrams per deciliter (mg/dL) at 6 Months
Time frame: At 6 months
Percentage of Participants Who Achieve Fasting TG ≤ 880 mg/dL at 12, 24, 36 months
Time frame: At 12, 24, 36 months
Adjudicated Acute Pancreatitis Event Rate During the Treatment Period in Participants With ≥ 2 Events of Adjudicated Acute Pancreatitis in 5 Years Prior to Treatment With Study Drug in the Index Study
Time frame: Week 1 through Week 157
Adjudicated Acute Pancreatitis Event Rate During the Treatment Period
Time frame: Week 1 through Weeks 53, 105, or 157
Adjudicated Acute Pancreatitis Event Rate During the Treatment Period in Patients with a Prior History of Pancreatitis within 10 Years Prior to Screening in the Index Study
Time frame: Week 1 through Weeks 53, 105, or 157
Percentage of Participants Who Achieve ≥ 70% Reduction in Fasting TG From Baseline at 6 Months
Time frame: At 6 months
Percentage of Participants Who Achieve ≥ 70% Reduction in Fasting TG From Baseline at 12, 24, 36 Months
Time frame: At 12, 24, 36 months
Percentage of Participants Who Achieve Fasting TG ≤ 500 mg/dL at 6 Months
Time frame: At 6 months
Percentage of Participants Who Achieve Fasting TG ≤ 500 mg/dL at 12, 24, 36 Months
Time frame: At 12, 24, 36 months
Plan to share: Yes — Ionis may share anonymized individual participant data, aggregated clinical data, and other types of data that support the results in this study. Data requests from qualified researchers will be considered once all three of the following criteria are met: (1) 12 months from marketing approval of the study drug in both the United States and European Union; (2) 18 months from conclusion of the study; and (3) 6 months from publication of study article. Access would be via a secure environment and is contingent upon approval of a research proposal and entry into an appropriate data use agreement. Requests to access data can be submitted via the website https://vivli.org/ourmember/ionis/.
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This study is active, not recruiting, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.
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Familial hyperchylomicronemia syndrome
Ionis Pharmaceuticals, Inc.