An Updated Review of Novel Triglyceride-Lowering Therapies in Adults with Familial Chylomicronemia Syndrome.

Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder resulting in hypertriglyceridemia. Historically, treatment options for this patient population have been limited as available triglyceride-lowering medications are often ineffective. Recently, new pharmacological agents targeting apolipoprotein C-III (apoC-III) production have been found to effectively and substantially lower triglyceride levels. A literature search in PubMed and EMBASE was conducted from January 2013 to July 2025 using keywords "familial chylomicronemia syndrome", "olezarsen", "volanesorsen", and "plozasiran". Phase III trials evaluating safety and efficacy of volanesorsen, olezarsen, and plozasiran were included. From 1376 articles, 4 phase III trials fulfilled the inclusion criteria. Triglyceride (TG) levels were reduced by 73-77% with volanesorsen, a least-square means reduction in TGs between 22.4 and 43.5 percentage points with olezarsen, and a 78-80% reduction in TGs with plozasiran when compared with placebo. The number of acute pancreatitis events was also lower with the study medications versus placebo. These new apoC-III lowering medications provide a novel treatment approach for patients with FCS, a population long without effective pharmacological treatment options. Provider familiarity with the availability and purpose of these medications will allow patients to receive the best therapy available to manage FCS.