Ionis Pharmaceuticals’ olezarsen meets primary Phase 3 efficacy endpoint

Ionis Pharmaceuticals announced positive topline results for the Phase 3 Balance study of olezarsen in people with familial chylomicronemia syndrome – FCS -. The trial met its primary efficacy endpoint with a statistically significant reduction in triglyceride levels with the olezarsen 80 mg monthly dose at six months compared to placebo; triglyceride lowering continued to improve at 12 months. In addition, olezarsen 80 mg showed a 100% reduction in acute pancreatitis events compared to placebo, a key secondary endpoint. Treatment with olezarsen 80 mg resulted in a greater than75% reduction in apoC-III, a protein produced in the liver that regulates TG metabolism in the blood. Olezarsen demonstrated a dose-dependent effect, with both study doses showing a substantial reduction in pancreatitis. The lower 50 mg dose did not reach statistical significance at six months on the primary endpoint of triglyceride lowering. Ionis plans to file a New Drug Application in early 2024 with the FDA in addition to EU regulatory filings. If approved, olezarsen would be the first available treatment in the U.S. for FCS, a rare, debilitating genetic disease that can lead to acute, potentially fatal pancreatitis attacks. The FDA granted olezarsen Fast Track designation for the treatment of FCS in 2023. Olezarsen demonstrated a favorable safety and tolerability profile in the study. There were more adverse events in the placebo group compared to the olezarsen groups, primarily due to pancreatitis events.