Olezarsen: A Next-Generation Antisense Therapy for Hypertriglyceridemia and Familial Chylomicronemia Syndrome

Olezarsen (Tryngolza) is a next-generation, N-acetylgalactosamine (GalNAc)-conjugated antisense oligonucleotide that selectively inhibits hepatic ApoC-III, a key regulator of triglyceride metabolism. By inhibiting ApoC-III, olezarsen increases triglyceride clearance through both lipoprotein lipase (LPL)-dependent and -independent pathways. In the Phase 3 BALANCE trial, olezarsen reduced fasting triglycerides by approximately 60% at 12 months in patients with familial chylomicronemia syndrome (FCS), with a marked decrease in pancreatitis events versus placebo. Consistent triglyceride reductions (around 50%) were also observed in moderate and severe hypertriglyceridemia, along with improvements in ApoB-containing lipoproteins and high-density lipoprotein (HDL) profiles. In completed trials, olezarsen demonstrated a favorable safety profile, with most adverse events limited to mild injection-site reactions and no clinically significant thrombocytopenia. Ongoing Phase 3 trials (ESSENCE, CORE, and CORE2) will further define its role in cardiovascular risk reduction and pancreatitis prevention in broader hypertriglyceridemic populations. Olezarsen represents a precision medicine advance, offering effective triglyceride lowering with improved tolerability compared with earlier antisense therapies.