X0508 4 2025-12-17 0 0000879407 ARROWHEAD PHARMACEUTICALS, INC. ARWR 0001423029 Anzalone Christopher Richard 177 E. COLORADO BLVD SUITE 700 PASADENA CA 91105 1 1 0 0 Chief Executive Officer 0 Common Stock 2025-12-17 4 S 0 46287 63.55 D 3870670 D Common Stock 2025-12-17 4 S 0 35750 64.51 D 3834920 D Common Stock 2025-12-17 4 S 0 982 65.53 D 3833938 D Common Stock 2025-12-17 4 S 0 1981 66.30 D 3831957 D Shares sold exclusively to cover anticipated taxes on performance awards that vested December 12, 2025. These performance awards were previously reported on form 4. The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $63.07 to $64.05, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote of this Form 4. Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person, a portion of which are still subject to certain vesting conditions. The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $64.06 to $64.84, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote of this Form 4. The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $65.48 to $65.54, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote of this Form 4. The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $66.03 to $66.48, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote of this Form 4. /s/Christopher Anzalone 2025-12-19