Olezarsen, a (GalNAc)-conjugated, antisense oligonucleotide (ASO) targeted to hepatic APOC3 mRNA to inhibit apoC-III, has received Orphan Drug designation from the FDA for familial chylomicronemia syndrome (FCS).

FCS is a rare, genetic disease that is characterized by extremely elevated triglyceride levels (10-100 times higher than normal) and recurrent acute pancreatitis. It is estimated that one to two people per million people worldwide are affected by FCS. People with FCS have impaired function of lipoprotein lipase, which leads to impaired breakdown of chylomicrons.

Olezarsen is designed to inhibit the production of apoC-III, a protein that regulates the metabolism of triglycerides in the blood. The FDA has granted the Orphan Drug designation to olezarsen for FCS. In addition, olezarsen is being investigated in phase 3 clinical trials for the treatment of severe hypertriglyceridemia.

The orphan drug status provides incentives for the sponsor, as well as seven year market exclusivity after drug approval.

Source: Press release Ionis Pharmaceuticals, Feb 15, 2024