Olezarsen and Beyond: Emerging Targeted Treatments for Familial Chylomicronemia Syndrome and Related Triglyceride Disorders

In familial chylomicronemia syndrome (FCS), a rare lipid disorder, triglycerides rise to extremely high levels because of the inability to utilize lipoprotein lipase (LPL) for fat metabolism. Traditional triglyceride-lowering medications are ineffective, leaving patients dependent on strict low-fat diets. This review examines emerging non-LPL-based therapies for FCS. This narrative review assessed therapeutic strategies targeting key regulators of triglyceride metabolism, including apolipoprotein C-III (APOC3) and angiopoietin-like protein 3 (ANGPTL3), in both animal and human studies. Investigational approaches included monoclonal antibodies, RNA-based therapies, gene therapy modalities, genome editing platforms, and plasmapheresis. Olezarsen effectively lowers triglycerides with greater safety than older options. Other agents, such as ANGPTL3 inhibitors and RNA interference therapies, also reduce lipids and provide additional treatment options. Gene therapy and clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 approaches are expected to become available in the near future, while plasmapheresis remains an intervention for acute pancreatitis. Innovative therapies targeting APOC3, ANGPTL3, or liver-specific genes are transforming the management of FCS. These advances not only address this rare disorder but also offer insights into treating triglyceride-related cardiovascular risk and lipid abnormalities. Although some uncertainties remain, the outlook for FCS therapy appears highly promising.