Arrowhead Pharmaceuticals' Plozasiran NDA Acceptance: A Breakthrough for Familial Chylomicronemia Syndrome

Arrowhead Pharmaceuticals, Inc. (NASDAQ: ARWR) has announced that the U.S. Food and Drug Administration (FDA) has accepted the New Drug Application (NDA) for investigational plozasiran for the treatment of familial chylomicronemia syndrome (FCS), a severe and rare genetic disease with no approved therapies in the U.S. The FDA provided a Prescription Drug User Fee Act (PDUFA) action date of November 18, 2025, and indicated it is not currently planning to hold an advisory committee meeting. This acceptance marks a significant milestone for Arrowhead and the FCS community, as it brings the company one step closer to potentially launching a new drug on the market.

The NDA submission is based on positive results from the Phase 3 PALISADE study, which successfully met its primary endpoint and all multiplicity-controlled key secondary endpoints, including statistically significant reductions in triglycerides (TGs), apolipoprotein C-III (APOC3), and the incidence of acute pancreatitis (AP). In PALISADE, plozasiran achieved deep and durable reductions in triglycerides, with a median change from baseline of 80% in the plozasiran 25 mg group and a statistically significant 83% reduction in the risk of developing acute pancreatitis compared to placebo in the pooled plozasiran 25 mg and 50 mg group. Overall, plozasiran has been generally well-tolerated to date, with the most frequently reported treatment emergent adverse events for the 25 mg dose being abdominal pain, COVID-19, nasopharyngitis, and nausea.

The acceptance of the NDA by the FDA is a testament to the strong clinical data generated by Arrowhead's plozasiran program. The company's commitment to developing innovative therapies for rare and underserved diseases has paid off, as plozasiran has shown promising results in multiple clinical studies. The positive results from the PALISADE study, along with supportive confirmatory evidence from the Phase 2 clinical studies of the SUMMIT Program, have provided a solid foundation for the NDA submission.

Arrowhead plans to file a New Drug Application by year-end 2024, pending the FDA's final decision on approval. If approved, plozasiran would be the first FDA-approved treatment for FCS, a severe and rare genetic disease with significant unmet medical need. The approval of plozasiran would provide a much-needed therapeutic option for patients with FCS, who currently have no approved treatments in the U.S.

The acceptance of the NDA for plozasiran by the FDA is a positive development for Arrowhead Pharmaceuticals, as it brings the company one step closer to potentially launching a new drug on the market. The company's commitment to developing innovative therapies for rare and underserved diseases has paid off, as plozasiran has shown promising results in multiple clinical studies. If approved, plozasiran would be the first FDA-approved treatment for FCS, a severe and rare genetic disease with significant unmet medical need. The approval of plozasiran would provide a much-needed therapeutic option for patients with FCS, who currently have no approved treatments in the U.S.



In conclusion, the acceptance of the NDA for plozasiran by the FDA is a significant milestone for Arrowhead Pharmaceuticals and the FCS community. The positive results from the PALISADE study, along with the company's commitment to developing innovative therapies for rare and underserved diseases, have positioned plozasiran as a potential breakthrough treatment for FCS. If approved, plozasiran would provide a much-needed therapeutic option for patients with FCS, who currently have no approved treatments in the U.S. Investors should closely monitor the progress of plozasiran's development and the FDA's final decision on approval.