PASADENA, Calif., June 22, 2026
Arrowhead Pharmaceuticals has reached a major regulatory milestone after the European Commission (EC) granted marketing authorization for REDEMPLO® (plozasiran), a small interfering RNA (siRNA) therapy indicated as an adjunct to diet for reducing triglyceride levels in adults with Familial Chylomicronemia Syndrome (FCS). The approval makes REDEMPLO® the first and only siRNA medicine authorized in the European Union for adults living with FCS and the first approved treatment that does not require genetic confirmation of the disease for eligible patients. The authorization is supported by compelling results from the Phase 3 PALISADE clinical trial, where REDEMPLO® demonstrated significant reductions in triglyceride levels while lowering the incidence of acute pancreatitis, a serious and potentially life-threatening complication of FCS. The latest approval reinforces Arrowhead Pharmaceuticals’ leadership in RNA interference (RNAi) therapeutics and expands treatment options for patients affected by this rare inherited lipid disorder.
Phase 3 PALISADE Trial Demonstrates Strong Clinical Benefit
The European Commission approval is based on positive findings from the Phase 3 PALISADE study, which evaluated the efficacy and safety of REDEMPLO® in adults diagnosed with Familial Chylomicronemia Syndrome. Clinical data showed that patients receiving the 25 mg dose experienced an 80% reduction in triglyceride levels from baseline, demonstrating robust lipid-lowering efficacy. In pooled analyses across treatment groups, the therapy also achieved an 83% reduction in the incidence of acute pancreatitis compared with placebo, addressing one of the most serious complications associated with FCS.
Characterized by extremely elevated triglyceride levels resulting from impaired chylomicron metabolism, FCS significantly increases the risk of recurrent pancreatitis, chronic abdominal pain, fatigue, and reduced quality of life. By delivering sustained triglyceride reductions through targeted RNA interference technology, REDEMPLO® offers a new therapeutic option capable of addressing the underlying disease process while reducing the burden of severe clinical complications.
RNAi Innovation Expands Treatment Options for Rare Disease
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REDEMPLO® (plozasiran) is an RNA interference (RNAi)-based medicine developed using Arrowhead’s proprietary Targeted RNAi Molecule (TRiM™) platform, which enables selective silencing of disease-causing genes involved in lipid metabolism. The therapy is designed to reduce production of apolipoprotein C-III (APOC3), an important regulator of triglyceride metabolism whose overexpression contributes to severe hypertriglyceridemia in patients with FCS. Unlike previous treatment approaches that primarily rely on strict dietary fat restriction and supportive care, REDEMPLO® directly targets the molecular mechanisms responsible for elevated triglycerides.
Importantly, the European approval allows treatment based on clinical diagnostic criteria, eliminating the requirement for genetic confirmation, which may improve access for eligible patients across the European Union. This milestone further validates the growing role of RNAi therapeutics in addressing rare metabolic diseases with high unmet medical need.
Global Regulatory Success Strengthens Arrowhead’s RNAi Portfolio
The European authorization follows previous regulatory approvals in the United States, Canada, Australia, and China, reflecting growing international recognition of REDEMPLO® as an important new treatment for Familial Chylomicronemia Syndrome. The approval further strengthens Arrowhead Pharmaceuticals’ expanding cardiometabolic pipeline, which leverages RNA interference technology to develop precision medicines targeting genetically validated disease pathways. As demand continues to grow for highly targeted therapies capable of improving outcomes in rare and severe metabolic disorders, REDEMPLO® represents another significant advancement in precision medicine.
The latest European milestone also reinforces the commercial potential of RNAi-based therapeutics, positioning Arrowhead to expand its global presence while delivering innovative treatment options for patients with limited therapeutic alternatives. By combining scientific innovation, targeted gene silencing, and strong clinical efficacy, REDEMPLO® has the potential to transform the long-term management of Familial Chylomicronemia Syndrome, offering new hope for patients living with one of the world’s rarest and most challenging lipid disorders.
Source: Arrowhead Pharmaceuticals press release
