Arrowhead Pharmaceuticals Presents Phase 3 SHASTA-3 and SHASTA-4 Data Demonstrating Plozasiran Reduced Acute Pancreatitis Events in Patients with Severe Hypertriglyceridemia
- Plozasiran reduced triglycerides (TG) by 79% and 81% versus placebo in SHASTA-3 and SHASTA-4 across the broad sHTG population -
- More than 90% of plozasiran-treated patients achieved triglycerides below thresholds for AP risk, 500 mg/dL at Month 12, and more than half achieved triglycerides below 150 mg/dL -
- Plozasiran reduced cumulative acute pancreatitis (AP) events by 78% versus placebo in patients with TG above 500 mg/dL, with or without a prior history of AP -
- Greater absolute benefit of AP risk reduction was observed in patients at higher risk -
- In the highest-risk subgroup, patients with TG above 880 mg/dL and a prior history of AP, there was a 100% reduction in events versus placebo -
- Plozasiran demonstrated a favorable safety and tolerability profile, with overall treatment-emergent adverse events similar between plozasiran and placebo groups -
- Arrowhead plans to file a supplemental New Drug Application with the U.S. FDA by year-end 2026 and utilize a Priority Review Voucher -
- Detailed results presented at the European Society of Cardiology (ESC) Congress 2026 in Munich as a Hot Line Late-Breaking Science session -
PASADENA, Calif., August 30, 2026--Arrowhead Pharmaceuticals, Inc. (NASDAQ: ARWR) today presented results from the pivotal Phase 3 SHASTA-3 and SHASTA-4 studies of plozasiran in adults with severe hypertriglyceridemia (sHTG) during a Hot Line Late-Breaking Science session at the European Society of Cardiology (ESC) Congress 2026 in Munich, Germany.
SHASTA-3 and SHASTA-4 met their primary and all prespecified secondary endpoints and demonstrated deep and durable reductions in triglycerides (TG), with median reductions from baseline of 79% and 81%, respectively at Month 12 (p<0.0001 in both studies). In a prespecified pooled analysis, plozasiran also significantly reduced acute pancreatitis (AP) events across the broad sHTG study population, with greater absolute benefit observed among patients at higher risk of AP. More than 90% of plozasiran-treated patients in both studies achieved TG levels below 500 mg/dL (<5.65 mmol/L) at Month 12, and more than half achieved TG levels below 150 mg/dL (<1.69 mmol/L).
"These SHASTA-3 and -4 results build on the compelling topline data we reported in July and further strengthen our view that plozasiran has the potential to fundamentally change how severe hypertriglyceridemia is treated," said Christopher Anzalone, Ph.D., President and Chief Executive Officer at Arrowhead. "The depth and consistency of triglyceride lowering across two large pivotal studies are impressive, but what may be most important for patients and physicians is the significant reduction in acute pancreatitis. The benefit was particularly pronounced among patients with a prior history of pancreatitis, a population with substantial ongoing risk. Combined with quarterly dosing and a favorable safety and tolerability profile, we believe these data demonstrate a highly differentiated profile for plozasiran and unequivocally support our plans to seek regulatory approval for the broader sHTG population. Our purchase of a U.S. FDA Priority Review Voucher, announced earlier this month, will potentially accelerate our goal of getting this important new medicine to patients."