144/A 0002044416-26-000001 0002044416 XXXXXXXX LIVE 0001437402 ARDELYX, INC. 001-36485 400 Fifth Avenue, Suite 210 Waltham MA 02451 510-745-1700 Reilly Joseph James Officer Common Stock Morgan Stanley Smith Barney LLC Executive Financial Services

1 New York Plaza, 8th Floor New York NY 10004

4991 33539.52 245247427 02/20/2026 NASDAQ Common Stock 02/19/2026 Vesting of restricted stock units Issuer N 10388 02/19/2026 Services Rendered N Joseph James Reilly

400 Fifth Avenue, Suite 210 Waltham MA 02451

Common Stock 11/21/2025 11086 61382.07 Pursuant to an automatic sell-to-cover imposed by the terms of the initial grant of the restricted stock units (RSUs) awards, the shares are to be sold upon the vesting of the RSUs solely to cover applicable withholding taxes. This amendment to Form 144 filed on February 20, 2026, amends by increasing the number of shares to be sold by 91 shares and amends the aggregate market value in accordance with instruction 3(d). The original filing underestimated the share count due to a lower than expected execution price in an automated tax withholding sell-to-cover transaction. 02/23/2026 Elizabeth Grammer, as Attorney-in-Fact for Joseph James Reilly