Arrowhead Pharmaceuticals Secures $200 Million Novartis Deal for Alpha-Synuclein siRNA Therapy
Key Insights
Arrowhead Pharmaceuticals announced a global collaboration with Novartis for ARO-SNCA, a preclinical siRNA candidate targeting alpha-synuclein (search) for synucleinopathies (search) including Parkinson's disease (search).
The agreement includes a $200 million upfront payment and potential milestone payments up to $2 billion, plus royalties on commercial sales.
Positive Phase 3 results from Ionis' olezarsen in severe hypertriglyceridemia (search) provide encouraging read-through for Arrowhead's competing plozasiran program.
Arrowhead Pharmaceuticals announced on September 2, 2025, a global collaboration and licensing agreement with Novartis for ARO-SNCA, a preclinical stage siRNA candidate that targets alpha-synuclein (search) for the treatment of synucleinopathies (search), including Parkinson's disease (search). The deal includes a substantial $200 million upfront payment and positions Arrowhead to receive up to $2 billion in milestone payments along with royalties on commercial sales.
Strategic Partnership Structure
The collaboration extends beyond ARO-SNCA to include additional targets utilizing Arrowhead's TRiM platform technology. Under the agreement terms, Arrowhead will conduct and complete preclinical research activities required for clinical trial application filing, with Novartis subsequently assuming control over development, manufacturing, and commercialization activities. The collaboration agreement is expected to close in the second half of 2025.
Competitive Landscape Validation
The announcement comes alongside positive developments in the broader RNA therapeutics space. On the same day, Ionis Pharmaceuticals (search) reported positive topline results from Phase 3 CORE and CORE2 trials of olezarsen in patients with severe hypertriglyceridemia (search) (sHTG). The study demonstrated a statistically significant placebo-adjusted mean reduction in fasting triglycerides of up to 72% and an 85% reduction in acute pancreatitis events. Adverse events were generally balanced across treatment groups, with serious adverse events occurring less frequently in the olezarsen group compared to placebo.
These results provide encouraging read-through for Arrowhead's plozasiran program in sHTG, currently being evaluated in the fully enrolled SHASTA-3 and SHASTA-4 trials. The trials are anticipated to complete in mid-2026, with a planned supplemental new drug application filing in the fourth quarter of 2026. An NDA for plozasiran for familial chylomicronemia syndrome (search) treatment is currently under FDA evaluation with a PDUFA date of November 18, 2025.
Financial Milestones and Strategic Positioning
The Novartis collaboration represents the latest in a series of strategic partnerships for Arrowhead. In August 2025, the company received a $100 million milestone payment from Sarepta Therapeutics tied to enrollment in the Phase 1 trial of ARO-DM1. Arrowhead elected to receive approximately $50 million in company stock, which was placed into treasury to reduce outstanding shares, and $50 million in cash. A second milestone payment of $200 million from Sarepta is expected before the end of calendar 2025.
Platform Technology Advancement
The collaboration highlights the potential of Arrowhead's TRiM platform technology in addressing neurological disorders. ARO-SNCA represents a novel approach to targeting alpha-synuclein (search), a protein implicated in various synucleinopathies (search) including Parkinson's disease (search). The partnership structure allows Arrowhead to leverage its platform capabilities while benefiting from Novartis' development and commercialization expertise.
The agreement reflects growing industry confidence in RNA interference therapeutics for neurological applications and validates Arrowhead's strategic approach of forming partnerships to advance multiple pipeline candidates while strengthening its financial position.