ARDELYX, INC.

Entry into a Material Definitive Agreement

On April 28, 2026, Ardelyx, Inc. (the Company) entered into a Sixth Amendment (the Sixth Amendment) to the Loan and Security Agreement, originally dated February 23, 2022, by and among the Company, as borrower, SLR Investment Corp. (SLR), as collateral agent and the lenders party thereto (as later amended, amended and restated, supplemented or otherwise modified from time to time).

Pursuant to the Sixth Amendment, among other things, (i) a portion of $200.0 million in outstanding principal previously allocated among the outstanding Term A through C Loans (collectively, the Revised Loans) was refinanced with a new Term H Loan; (ii) the maturity date for the Revised Loans has been extended from July 1, 2028 to July 1, 2030 (the New Maturity Date), which is the maturity date applicable for each other term loan; (iii) the interest-only payment period for the Revised Loans has been extended until the New Maturity Date; (iv) the interest rates for the Revised Loans, the Term H Loan, and the Term F and Term G Loans will have a collectively reduced interest rate, at the sum of 4.55% plus the greater of (a) the 1-month SOFR reference rate or (b) 3.5%; (v) the Company will retain the option to draw the Term F and Term G Loans, each in the amount of $50.0 million, at the Company’s election by June 30, 2026 and December 20, 2026, respectively; and (vi) certain negative covenants and other conditions were amended to provide additional flexibility to the Company.

On the closing date of the Sixth Amendment, the Company paid approximately $1.9 million in final fees and prepayment fees in connection with the partial paydown of the Term A through C Loans.

The Company is obligated to pay a final fee with respect to each of the outstanding amounts under each of the term loans, upon the earliest to occur of (i) the New Maturity Date, (ii) the acceleration of the applicable term loan or (iii) the prepayment, refinancing, substitution or replacement of the applicable term loan. This final fee is 4.95% for the Term A through E loans, 3.45% for the Term F and Term G Loans and 2.50% for the new Term H Loan.

The above summary of the material terms of the Sixth Amendment does not purport to be complete and is qualified in its entirety by reference to the Sixth Amendment, a copy of which is filed as Exhibit 10.3 to this Quarterly Report on Form 10-Q and incorporated by reference herein.

Trading Plans

During the three months ended March 31, 2026, our Section 16 officers and directors adopted orterminated contracts, instructions or written plans for the purchase or sale of our securities as noted below.