ARDELYX, INC. 10-Q

ITEM 1. FINANCIAL STATEMENTS ARDELYX, INC. CONDENSED BALANCE SHEETS (Unaudited) (in thousands, except share and per share amounts) March 31, 2026 December 31, 2025 Assets Current assets Cash and cash equivalents $ 31,209 $ 67,999 Short-term investments 206,865 196,690 Accounts receivable 82,840 71,848 Inventory 22,745 17,735 Prepaid commercial manufacturing 14,635 14,479 Prepaid expenses and other current assets 23,576 13,566 Total current assets 381,870 382,317 Property and equipment, net 2,002 2,184 Inventory, non-current 105,280 105,372 Prepaid commercial manufacturing, non-current 4,238 — Right-of-use assets 4,433 4,795 Other assets 6,684 6,936 Total assets $ 504,507 $ 501,604 Liabilities and stockholders’ equity Current liabilities Accounts payable $ 28,195 $ 19,235 Accrued compensation and benefits 9,382 19,108 Current portion of operating lease liability 1,510 1,479 Deferred revenue 3,248 1,206 Accrued expenses and other current liabilities 67,233 47,577 Total current liabilities 109,568 88,605 Operating lease liability, net of current portion 3,237 3,641 Long-term debt 203,517 202,834 Deferred revenue, non-current 13,699 13,699 Deferred royalty obligation related to the sale of future royalties 25,864 25,876 Total liabilities 355,885 334,655 Commitments and contingencies (Note 14) Stockholders’ equity Common stock, $ 0.0001 par value per share; 500,000,000 shares authorized; 246,973,414 and 244,351,501 shares issued and outstanding as of March 31, 2026 and December 31, 2025, respectively 25 24 Additional paid-in capital 1,133,265 1,113,666 Accumulated deficit ( 984,544 ) ( 946,939 ) Accumulated other comprehensive (loss) income ( 124 ) 198 Total stockholders’ equity 148,622 166,949 Total liabilities and stockholders’ equity $ 504,507 $ 501,604 The accompanying notes are an integral part of these condensed financial statements. 2 Table of Contents ARDELYX, INC. CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) (in thousands, except share and per share amounts) Three Months Ended March 31, 2026 2025 Revenues Product sales, net $ 93,373 $ 67,814 Product supply revenue 354 254 Licensing revenue 51 5,020 Non-cash royalty revenue related to the sale of future royalties 695 1,026 Total revenues 94,473 74,114 Costs and operating expenses Cost of sales 4,811 12,303 Research and development 20,188 14,938 Selling, general and administrative 102,267 83,222 Total costs and operating expenses 127,266 110,463 Loss from operations ( 32,793 ) ( 36,349 ) Interest expense ( 5,599 ) ( 4,191 ) Non-cash interest expense related to the sale of future royalties ( 1,317 ) ( 2,071 ) Other income, net 2,112 2,326 Loss before provision for income taxes ( 37,597 ) ( 40,285 ) Provision for income taxes 8 859 Net loss $ ( 37,605 ) $ ( 41,144 ) Net loss per share of common stock - basic and diluted $ ( 0.15 ) $ ( 0.17 ) Shares used in computing net loss per share - basic and diluted 245,855,082 238,624,145 Comprehensive loss Net loss $ ( 37,605 ) $ ( 41,144 ) Unrealized losses on available-for-sale securities ( 322 ) ( 39 ) Comprehensive loss $ ( 37,927 ) $ ( 41,183 ) The accompanying notes are an integral part of these condensed financial statements. 3 Table of Contents ARDELYX, INC. CONDENSED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY (Unaudited) (in thousands, except share amounts) Three Months Ended March 31, 2026 Common Stock Additional Paid-In Capital Accumulated Deficit Accumulated Other Comprehensive Income (Loss) Total Stockholders’ Equity Shares Amount Balance as of December 31, 2025 244,351,501 $ 24 $ 1,113,666 $ ( 946,939 ) $ 198 $ 166,949 Issuance of common stock under employee stock purchase plan 136,480 — 742 — — 742 Issuance of common stock upon exercise of options 1,100,306 1 4,699 — — 4,700 Issuance of common stock upon vesting of restricted stock units 1,385,127 — — — — — Stock-based compensation — — 14,158 — — 14,158 Unrealized losses on available-for-sale securities — — — — ( 322 ) ( 322 ) Net loss — — — ( 37,605 ) — ( 37,605 ) Balance as of March 31, 2026 246,973,414 $ 25 $ 1,133,265 $ ( 984,544 ) $ ( 124 ) $ 148,622 Three Months Ended March 31, 2025 Common Stock Additional Paid-In Capital Accumulated Deficit Accumulated Other Comprehensive Income (Loss) Total Stockholders’ Equity Shares Amount Balance as of December 31, 2024 238,015,825 $ 24 $ 1,058,548 $ ( 885,340 ) $ 57 $ 173,289 Issuance of common stock under employee stock purchase plan 222,734 — 1,015 — — 1,015 Issuance of common stock upon exercise of options 389,963 — 467 — — 467 Issuance of common stock upon vesting of restricted stock units 572,734 — — — — — Stock-based compensation — — 12,088 — — 12,088 Unrealized losses on available-for-sale securities — — — — ( 39 ) ( 39 ) Net loss — — — ( 41,144 ) — ( 41,144 ) Balance as of March 31, 2025 239,201,256 $ 24 $ 1,072,118 $ ( 926,484 ) $ 18 $ 145,676 The accompanying notes are an integral part of these condensed financial statements. 4 Table of Contents ARDELYX, INC. CONDENSED STATEMENTS OF CASH FLOWS (Unaudited) (in thousands) Three Months Ended March 31, 2026 2025 Operating activities Net loss $ ( 37,605 ) $ ( 41,144 ) Adjustments to reconcile net loss to net cash used in operating activities Depreciation and amortization expense 915 602 Non-cash lease expense 362 923 Stock-based compensation 14,158 12,088 Non-cash interest expense 1,582 2,136 Non-cash royalty revenue related to the sale of future royalties ( 695 ) ( 1,026 ) Other, net ( 571 ) ( 1,191 ) Changes in operating assets and liabilities Accounts receivable ( 10,992 ) 11,238 Inventory ( 4,918 ) ( 14,692 ) Prepaid commercial manufacturing ( 4,394 ) ( 716 ) Prepaid expenses and other assets ( 10,004 ) ( 5,022 ) Accounts payable 8,960 ( 2,278 ) Accrued compensation and benefits ( 9,726 ) ( 7,772 ) Operating lease liabilities ( 373 ) ( 991 ) Accrued and other liabilities 19,022 8,043 Deferred revenue 2,042 1,345 Net cash used in operating activities ( 32,237 ) ( 38,457 ) Investing activities Proceeds from maturities and redemptions of investments 37,950 34,726 Purchases of investments ( 47,876 ) ( 31,550 ) Purchases of property and equipment ( 69 ) ( 325 ) Net cash (used in) provided by investing activities ( 9,995 ) 2,851 Financing activities Proceeds from issuance of common stock under equity incentive plans 5,442 1,482 Net cash provided by financing activities 5,442 1,482 Net decrease in cash and cash equivalents ( 36,790 ) ( 34,124 ) Cash and cash equivalents at beginning of period 67,999 64,932 Cash and cash equivalents at end of period $ 31,209 $ 30,808 Supplemental disclosure of cash flow information Cash paid for interest $ 3,114 $ 2,454 Cash (refunded) paid for income taxes $ ( 69 ) $ 2 Supplemental disclosure of non-cash activity Right-of-use assets obtained in exchange for lease obligations $ — $ 2,213 The accompanying notes are an integral part of these condensed financial statements. 5 Table of Contents ARDELYX, INC . NOTES TO CONDENSED FINANCIAL STATEMENTS (Unaudited) NOTE 1. NATURE OF OPERATIONS We are a commercial-stage biopharmaceutical company focused on the development and commercialization of innovative medicines that meet significant unmet medical needs. We currently market two therapies from the active ingredient tenapanor, a sodium/hydrogen exchanger (NHE3) inhibitor that was discovered and developed by Ardelyx. NHE3 is an antiporter expressed on the apical surface of the small and large intestines. Tenapanor is a minimally absorbed, small molecule therapy. Tenapanor, branded as IBSRELA ® , is approved in the U.S. for the treatment of adults with irritable bowel syndrome with constipation (IBS-C). We are seeking to further expand the IBSRELA eligible patient population to include patients with chronic idiopathic constipation (CIC), and have initiated a Phase 3 clinical trial evaluating tenapanor in adult CIC patients. Tenapanor, branded as XPHOZAH ® , is approved in the U.S. to reduce serum phosphorus in adults with chronic kidney disease on dialysis as add-on therapy in patients who have an inadequate response to phosphate binders or who are intolerant of any dose of phosphate binder therapy. We are also developing a next-generation NHE3 inhibitor, RDX10531, which has demonstrated in preclinical models to have improved solubility and potency compared to tenapanor. We believe that RDX10531 can have application across multiple therapeutic areas. We operate in one business segment, which is the development and commercialization of biopharmaceutical products. Refer to Note 12. Segment Reporting for further segment reporting information. Basis of Presentation These condensed financial statements have been prepared in accordance with U.S. GAAP and pursuant to the requirements of the SEC for interim reporting. As permitted under those rules and regulations, certain footnotes or other financial information that are normally required by U.S. GAAP have been condensed or omitted. These condensed financial statements have been prepared on the same basis as our most recent annual financial statements and, in the opinion of management, reflect all normal and recurring adjustments necessary to present fairly our financial position, results of operations, changes in stockholders’ equity and cash flows for the interim periods presented. Certain prior year amounts have been reclassified to conform to the current year presentation on the condensed statements of operations and comprehensive loss to include the “cost of product sales” and the “other cost of revenue” captions within the “cost of sales” caption. Certain prior year amounts have also been reclassified to conform to the current year presentation in Note 12. Segment Reporting . These reclassifications had no effect on the previously reported results of operations. The accompanying condensed financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto included in our 2025 Form 10-K. The results for the three months ended March 31, 2026 are not necessarily indicative of results to be expected for the entire year ending December 31, 2026, or for any other interim period or future year. Refer to the Summary of Abbreviated Terms at the end of this Quarterly Report on Form 10-Q for definitions of terms used throughout the document. Critical Accounting Policies and Estimates The preparation of financial statements requires management to make estimates, judgments and assumptions. The most significant assumptions are estimates used in our revenue gross-to-net accruals and other assumptions. Management bases its estimates on historical experience and on various other market-specific and relevant assumptions that management believes to be reasonable under the circumstances. Actual results could materially differ from those estimates. Our critical accounting policies and estimates are discussed in our 2025 Form 10-K. Concentration of Credit Risk Financial instruments that potentially subject us to significant concentrations of credit risk consist primarily of cash, cash equivalents, short-term investments and accounts receivable. We are exposed to credit risks in the event of default by the counterparties to the extent of the amount recorded in our balance sheets. Cash, cash equivalents and short-term investments are invested through banks and other financial institutions in the U.S. 6 Table of Contents Recent Accounting Pronouncements Recent Accounting Pronouncement Not Yet Adopted In November 2024, the FASB issued ASU No. 2024-03, Income Statement (Topic 220) - Reporting Comprehensive Income - Expense Disaggregation Disclosures, Disaggregation of Income Statement Expenses , which requires public companies to disclose, in interim and annual reporting periods, additional information about certain expenses in the financial statements. The new disclosure requirements are effective for the Company’s annual periods beginning January 1, 2027, and interim periods beginning January 1, 2028, with early adoption permitted, and may be applied either prospectively or retrospectively. The Company is in the process of evaluating the impact of this new guidance on its disclosures. NOTE 2. CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS The following table summarizes our cash, cash equivalents and short-term investments: March 31, 2026 December 31, 2025 Gross Unrealized Gross Unrealized (in thousands) Amortized Cost Gains Losses Fair Value Amortized Cost Gains Losses Fair Value Cash and cash equivalents Cash $ 9,543 $ — $ — $ 9,543 $ 18,569 $ — $ — $ 18,569 Money market funds 21,666 — — 21,666 49,430 — — 49,430 Total cash and cash equivalents 31,209 — — 31,209 67,999 — — 67,999 Short-term investments U.S. treasury securities $ 94,379 $ 11 $ ( 38 ) $ 94,352 $ 95,052 $ 105 $ — $ 95,157 Commercial paper 48,958 3 ( 68 ) 48,893 46,421 32 ( 3 ) 46,450 U.S. government-sponsored agency bonds 35,266 5 ( 18 ) 35,253 27,330 36 — 27,366 Corporate bonds 23,274 3 ( 15 ) 23,262 22,557 25 — 22,582 Yankee bonds 5,112 — ( 7 ) 5,105 5,132 3 — 5,135 Total short-term investments 206,989 22 ( 146 ) 206,865 196,492 201 ( 3 ) 196,690 Total cash, cash equivalents and investments $ 238,198 $ 22 $ ( 146 ) $ 238,074 $ 264,491 $ 201 $ ( 3 ) $ 264,689 Realized gains or losses have not been significant and are included in other income, net in our condensed statements of operations and comprehensive loss. Unrealized losses as of March 31, 2026 and December 31, 2025 were not material. All of the short-term available-for-sale securities held as of March 31, 2026 and December 31, 2025 had contractual maturities of less than one year, and no investment was in a continuous unrealized loss position for more than one year. Therefore, we believe that it is more likely than not that the investments will be held until maturity or a forecasted recovery of fair value. Based on our procedures under the expected credit loss model, including an assessment of unrealized losses in our portfolio, we concluded that any unrealized losses on our marketable securities were not attributable to credit and, therefore, we have not recorded an allowance for credit losses for these securities as of March 31, 2026 and December 31, 2025. See “Cash Equivalents” and “Short-Term Investments” captions of Note 2. Summary of Significant Accounting Policies of our 2025 Form 10-K for more information on our accounting policies for cash equivalents and short-term investments. 7 Table of Contents NOTE 3. FAIR VALUE MEASUREMENTS Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The three-level hierarchy for the inputs to valuation techniques is briefly summarized as follows: Level 1 – Valuations are based on quoted prices in active markets for identical assets or liabilities and readily accessible by us at the reporting date. Level 2 – Valuations based on inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 – Valuations based on unobservable inputs for which there is little or no market data, which require us to develop our own assumptions. The following table sets forth the fair value of our financial assets that are measured or disclosed on a recurring basis by level within the fair value hierarchy: March 31, 2026 December 31, 2025 (in thousands) Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Assets Money market funds $ 21,666 $ 21,666 $ — $ — $ 49,430 $ 49,430 $ — $ — U.S. treasury securities 94,352 — 94,352 — 95,157 — 95,157 — Commercial paper 48,893 — 48,893 — 46,450 — 46,450 — U.S. government-sponsored agency bonds 35,253 — 35,253 — 27,366 — 27,366 — Corporate bonds 23,262 — 23,262 — 22,582 — 22,582 — Yankee bonds 5,105 — 5,105 — 5,135 — 5,135 — Total $ 228,531 $ 21,666 $ 206,865 $ — $ 246,120 $ 49,430 $ 196,690 $ — Fair Value of Debt The outstanding principal under our 2022 Loan Agreement is subject to a variable interest rate and therefore, we believe the carrying amount of the term loan facility approximated its fair value as of March 31, 2026 and December 31, 2025. See Note 8. Borrowing for a description of the Level 2 inputs used to estimate the fair value of the liability. The carrying value of the deferred royalty obligation related to the sale of future royalties approximated its fair value as of March 31, 2026 and December 31, 2025, and is based on our current estimates of future royalties and commercialization milestones expected to be received by HCR over the life of the HCR Agreement. See Note 7. Deferred Royalty Obligation Related to the Sale of Future Royalties . NOTE 4. INVENTORY Inventory consisted of the following: (in thousands) March 31, 2026 December 31, 2025 Raw materials $ 27,941 $ 28,009 Work in process 90,043 88,259 Finished goods 10,041 6,839 Total $ 128,025 $ 123,107 Reported as Inventory $ 22,745 $ 17,735 Inventory, non-current 105,280 105,372 Total $ 128,025 $ 123,107 8 Table of Contents Prepaid commercial manufacturing with third-party CMOs not included in inventory was $ 18.9 million and $ 14.5 million as of March 31, 2026 and December 31, 2025, respectively. There were $ 4.2 million prepayments expected to be converted into inventory after 12 months as of March 31, 2026, compared to none as of December 31, 2025. NOTE 5. REVENUE Disaggregation of total revenues by nature is as follows: Three Months Ended March 31, (in thousands) 2026 2025 Product sales, net $ 93,373 $ 67,814 Product supply revenue 354 254 Licensing revenue 51 5,020 Non-cash royalty revenue related to the sale of future royalties 695 1,026 Total revenues $ 94,473 $ 74,114 Product Sales, Net Total product sales, net was as follows: Three Months Ended March 31, (in thousands) 2026 2025 Product sales, net IBSRELA $ 70,074 $ 44,403 XPHOZAH 23,299 23,411 Total product sales, net $ 93,373 $ 67,814 Product sales, net as a percentage of total revenues 98.8 % 91.5 % Concentrations Gross product sales from Customers accounting for more than 10% of total revenues were as follows: Three Months Ended March 31, 2026 2025 Customers (1) BioRidge Pharma, LLC 85.5 % 63.8 % Cencora, Inc. 17.2 % 18.2 % McKesson Corporation 15.7 % 16.9 % Cardinal Health, Inc. 12.8 % 22.2 % Caremark, LLC 12.1 % — % (1) The total of the above percentages exceeds 100% as the numerators used in the calculations represent gross product sales for each Customer, as opposed to product sales, net as presented in our condensed statements of operations and comprehensive loss. 9 Table of Contents GTN Adjustments The activities and ending reserve balances for each significant category of GTN adjustments on product sales, net, which constitute variable consideration, were as follows: (in thousands) Discounts and Chargebacks Rebates, Wholesaler and GPO Fees Copay Assistance and Returns Total Balance as of December 31, 2025 $ 1,693 $ 34,456 $ 9,274 $ 45,423 Provisions (1) 8,205 29,969 15,071 53,245 Credits/payments ( 7,753 ) ( 25,012 ) ( 12,475 ) ( 45,240 ) Balance as of March 31, 2026 $ 2,145 $ 39,413 $ 11,870 $ 53,428 (1) Adjustments to prior period provisions recorded in the current period were not material. NOTE 6. COLLABORATION AND LICENSING AGREEMENTS We have out-licensed to external partners for the development and commercialization of tenapanor outside of the U.S. We recognize revenue from our collaboration partnerships as licensing revenue, product supply revenue or non-cash royalty revenue related to the sale of future royalties. See Note 7. Collaboration and Licensing Agreements and “Collaboration and Licensing Revenue” caption of Note 2. Summary of Significant Accounting Policies of our 2025 Form 10-K for more information on the nature, purpose, significant rights and obligations of the parties, as well as our accounting policies for such revenue streams. The following table summarizes total revenues by collaboration partner: Three Months Ended March 31, (in thousands) 2026 2025 Licensing revenue Knight $ 31 $ 20 Fosun Pharma 20 5,000 Total licensing revenue $ 51 $ 5,020 Product supply revenue Fosun Pharma $ 352 $ — Kyowa Kirin 2 — Knight — 254 Total supply revenue $ 354 $ 254 Non-cash royalty revenue related to the sale of future royalties Kyowa Kirin $ 695 $ 1,026 The following table presents changes in our current deferred revenue balances by collaboration partner: (in thousands) 2026 2025 Current Kyowa Kirin Fosun Pharma Total Kyowa Kirin Fosun Pharma Total Deferred revenue balance as of January 1, $ — $ 1,206 $ 1,206 $ 10,686 $ — $ 10,686 Prepaid product supply — 2,391 2,391 227 — 227 Product supply delivered — ( 349 ) ( 349 ) — — — Reclassify amounts to be recognized in the next 12 months — — — — — — Deferred revenue balance as of March 31, $ — $ 3,248 $ 3,248 $ 10,913 $ — $ 10,913 10 Table of Contents The following table presents changes in our non-current deferred revenue balances by collaboration partner: (in thousands) 2026 2025 Non-current Kyowa Kirin Fosun Pharma Total Kyowa Kirin Fosun Pharma Total Deferred revenue balance as of January 1, $ 13,699 $ — $ 13,699 $ 7,232 $ — $ 7,232 Prepaid product supply — — — 1,118 — 1,118 Product supply delivered — — — — — — Reclassify amounts to be recognized in the next 12 months — — — — — — Deferred revenue balance as of March 31, $ 13,699 $ — $ 13,699 $ 8,350 $ — $ 8,350 Significant developments and updates related to our collaboration partnerships in the three months ended March 31, 2026 and 2025 are discussed below. Fosun Pharma In March 2026, Fosun Pharma reported the first commercial sales of tenapanor, marketed under the Chinese trade name Wan Ti Le, for patients with CKD on hemodialysis with hyperphosphatemia in China. Pursuant to the terms of the license and manufacturing services agreements with Fosun Pharma, we are eligible to receive reimbursement of cost plus a reasonable overhead for the supply of product and tiered royalties on net sales ranging from the mid-teens to 20 %. In February 2025, we announced the NDA approval by China’s Center for Drug Evaluation of the NMPA for tenapanor in the control of serum phosphorus in adult patients with CKD on hemodialysis. This approval triggered a $ 5.0 million milestone to us, which was recorded as licensing revenue in our condensed statements of operations and comprehensive loss in the 2025 first quarter. Knight - Former Collaboration Partner Effective as of March 13, 2026, we entered into a termination agreement with Knight, pursuant to which we and Knight agreed to mutually terminate our exclusive license agreement for the development, commercialization and distribution of tenapanor in Canada for hyperphosphatemia and IBS-C. The decision was not related to any concerns regarding the safety, efficacy or quality of the product. Sales of IBSRELA in Canada were discontinued effective March 31, 2026. The termination did not have a material effect on our operations or financial results, and we do not expect it to adversely impact our operations or financial results in the future. AstraZeneca In connection with the AstraZeneca Termination Agreement, we recognized royalty expense as cost of sales in our condensed statements of operations and comprehensive loss of $ 8.8 million in the three months ended March 31, 2025. As of the end of the 2025 second quarter, we had fully recognized the maximum $ 75.0 million royalty obligation, which had been fully remitted as of the end of the 2025 third quarter. NOTE 7. DEFERRED ROYALTY OBLIGATION RELATED TO THE SALE OF FUTURE ROYALTIES We and HCR have an agreement in which HCR paid $ 15.0 million in exchange for royalty and commercialization milestone payments that we may receive under our Kyowa Kirin Agreement. See Note 8. Deferred Royalty Obligation Related to the Sale of Future Royalties of our 2025 Form 10-K for further discussion on the nature, purpose, significant rights and obligations of the parties, as well as our accounting policies regarding the HCR Agreement. Payments received from HCR are recorded as a deferred royalty obligation on our balance sheets, which is being amortized as non-cash interest expense over the estimated life of the HCR Agreement using the effective interest method. The deferred royalty obligation will be effectively repaid over the life of the HCR Agreement as we remit to HCR royalties and commercialization milestones paid to us by Kyowa Kirin. We periodically assess the estimated amounts and timing of future royalties and commercialization milestone payments from Kyowa Kirin and, to the extent that the amount or timing of such payments is materially different than our original estimates, we prospectively adjust the imputed interest rate and the related amortization of the deferred royalty obligation. 11 Table of Contents A summary of financial information related to the HCR Agreement is as follows: Three Months Ended March 31, ($ in thousands) 2026 2025 Non-cash interest expense related to the sale of future royalties $ ( 1,317 ) $ ( 2,071 ) Effective interest rate 20.4 % 32.5 % (in thousands) 2026 2025 Deferred royalty obligation balance as of January 1, $ 25,876 $ 25,527 Non-cash interest expense related to the sale of future royalties 1,317 2,071 Royalty and commercialization milestone payments remitted to HCR ( 1,329 ) ( 1,076 ) Deferred royalty obligation balance as of March 31, $ 25,864 $ 26,522 NOTE 8. BORROWING The following table presents our outstanding term loans under the 2022 Loan Agreement: (in thousands) March 31, 2026 December 31, 2025 Interest Rates Principal Term A Loan $ 27,500 $ 27,500 7.95 % + 0.022 % + SOFR (subject to a floor of 1.0 %) Term B Loan 22,500 22,500 7.95 % + 0.022 % + SOFR (subject to a floor of 1.0 %) Term C Loan 50,000 50,000 4.25 % + 0.022 % + SOFR (subject to a floor of 4.7 %) Term D Loan 50,000 50,000 4.00 % + 0.022 % + SOFR (subject to a floor of 4.7 %) Term E Loan 50,000 50,000 4.00 % + 0.022 % + SOFR (subject to a floor of 4.7 %) Total principal 200,000 200,000 Adjustments to principal value Unamortized discount and debt issuance costs ( 1,029 ) ( 1,127 ) Accreted value of final fee 4,546 3,961 Total long-term debt 203,517 202,834 Less: Current portion of long-term debt — — Long-term debt, net of current portion $ 203,517 $ 202,834 The total unaccreted final fee was $ 5.4 million and $ 5.9 million as of March 31, 2026 and December 31, 2025, respectively. As of March 31, 2026, our total future payment obligation related to the outstanding balance of the term loans, excluding interest payments, was $ 209.9 million, which is due on July 1, 2028. As of March 31, 2026, there have been no changes to the principal, maturity, interest rates, interest payment terms and debt covenants since December 31, 2025. See Note 9. Borrowing of our 2025 Form 10-K for additional information regarding our 2022 Loan Agreement. Effective as of April 28, 2026, we entered into the Sixth Amendment with SLR as collateral agent and the lenders party thereto. For additional information, refer to Note 15. Subsequent Events . 12 Table of Contents NOTE 9. LEASES The following table provides additional details of our facility leases presented in our condensed balance sheets: ($ in thousands) Facilities March 31, 2026 December 31, 2025 Right-of-use assets $ 4,433 $ 4,795 Current portion of lease liabilities $ 1,510 $ 1,479 Operating lease liability, net of current portion 3,237 3,641 Total lease liabilities $ 4,747 $ 5,120 Weighted-average remaining term (in years) 2.9 3.1 Weighted-average discount rate 5.6 % 5.6 % The following table presents the lease costs, which are included in our condensed statements of operations and comprehensive loss, and the supplemental cash flow information related to the leases: Three Months Ended March 31, (in thousands) 2026 2025 Operating lease expense $ 432 $ 977 Cash paid for operating leases $ 442 $ 1,047 The following table summarizes our undiscounted cash payment obligations for our operating lease liabilities as of March 31, 2026: (in thousands) Operating Leases Remainder of 2026 $ 1,342 2027 1,836 2028 1,402 2029 575 Thereafter — Total undiscounted operating lease payments 5,155 Imputed interest expenses ( 408 ) Total operating lease liabilities 4,747 Less: Current portion of operating lease liability ( 1,510 ) Operating lease liability, net of current portion $ 3,237 NOTE 10. STOCKHOLDERS’ EQUITY In November 2025, we filed an automatic shelf registration statement on Form S-3ASR, which became effective upon filing, containing (i) a base prospectus, which covers the offering, issuance and sale from time to time in one or more offerings of our common stock, preferred stock, debt securities, warrants and/or units; and (ii) a prospectus supplement for the offering, issuance and sale of up to a maximum aggregate offering price of $ 100.0 million of our common stock that may be issued and sold from time to time under the 2025 Open Market Sales Agreement, deemed to be “at-the-market offerings.” Pursuant to the 2025 Open Market Sales Agreement, Jefferies, as sales agent, may receive a commission of up to three percent of the gross sales price for shares of our common stock sold under the 2025 Open Market Sales Agreement. As of March 31, 2026, there have been no sales of our common stock under the 2025 Open Market Sales Agreement. 13 Table of Contents NOTE 11. EQUITY INCENTIVE PLANS Stock-Based Compensation Expense Stock-based compensation expense for stock options, RSUs and our ESPP included in our condensed statements of operations and comprehensive loss was as follows: Three Months Ended March 31, (in thousands) 2026 2025 Selling, general and administrative $ 11,556 $ 8,484 Research and development 2,602 3,604 Total $ 14,158 $ 12,088 A summary of our total unrecognized stock-based compensation expense, net of estimated forfeitures, as of March 31, 2026 is as follows: Unrecognized Compensation Expense (in thousands) Average Remaining Vesting Period (in years) Stock option grants $ 56,408 2.7 RSU grants $ 95,632 3.0 ESPP $ 318 0.4 Stock Options A summary of our stock option activity and related information for the three months ended March 31, 2026 is as follows: Number of Shares (in thousands) Weighted-Average Exercise Price per Share Balance as of December 31, 2025 28,977 $ 5.54 Options granted 2,948 $ 7.71 Options exercised ( 1,100 ) $ 4.27 Options forfeited or canceled ( 1,014 ) $ 9.03 Balance as of March 31, 2026 29,811 $ 5.69 Exercisable as of March 31, 2026 17,718 $ 5.31 Restricted Stock Units A summary of our RSU activity and related information for the three months ended March 31, 2026 is as follows: Number of RSUs (in thousands) Weighted-Average Grant Date Fair Value per Share Non-vested restricted stock units as of December 31, 2025 12,583 $ 5.71 Granted 5,274 $ 7.59 Vested ( 1,385 ) $ 6.16 Forfeited ( 540 ) $ 6.10 Non-vested restricted stock units as of March 31, 2026 15,932 $ 6.28 Employee Stock Purchase Plan During the three months ended March 31, 2026, we issued approximately 0.1 million shares of our common stock under the ESPP. The shares were purchased by employees at an average purchase price of $ 5.44 per share, resulting in proceeds to us of approximately $ 0.7 million. 14 Table of Contents NOTE 12. SEGMENT REPORTING We operate in a single reportable segment. The Chief Executive Officer is our Chief Operating Decision Maker, who primarily uses aggregated net loss as reported on the condensed statements of operations and comprehensive loss to measure segment loss, supplemented by certain additional significant expense details reflected in the table below. There have been no changes in the determination of segmentation or the measurements used to determine reported segment loss discussed in our 2025 Form 10-K. See Note 17. Segment Reporting of our 2025 Form 10-K for more discussion on our segment reporting. Detailed information regarding our single operating segment’s significant revenues, expenses and operating loss is as follows: Three Months Ended March 31, (in thousands) 2026 2025 Revenues Product sales, net $ 93,373 $ 67,814 Other revenues (1) 1,100 6,300 Total revenues 94,473 74,114 Less Cost of product sales (2) 2,875 2,340 Other cost of revenue (3) 1,936 9,963 Research and development (4) 17,586 11,335 Selling (4) 67,395 56,800 General and administrative (4) 23,316 17,937 Stock-based compensation 14,158 12,088 Total costs and operating expenses 127,266 110,463 Consolidated loss from operations ( 32,793 ) ( 36,349 ) Other reconciliation items (5) ( 4,812 ) ( 4,795 ) Consolidated net loss $ ( 37,605 ) $ ( 41,144 ) (1) Other revenues includes revenues from our collaboration partnerships, including licensing revenue, product supply revenue and non-cash royalty revenue related to the sale of future royalties. (2) Cost of product sales includes the cost of commercial goods sold to our Customers, such as the cost of materials, third-party contract manufacturing, third-party packaging services, freight, labor costs for personnel involved in the manufacturing process and indirect overhead costs. (3) Other cost of revenue includes the cost of materials sold to our collaboration partners under product supply agreements, certain costs related to capacity expansion at current and future CMOs and payments due to AstraZeneca. As of the end of the 2025 second quarter, the maximum $ 75.0 million royalty obligation under the AstraZeneca Termination Agreement had been fully recognized. (4) Research and development, selling and general and administrative expenses herein do not include stock-based compensation expenses. (5) Other reconciliation items includes interest expense, non-cash interest expense related to the sale of future royalties, provision for income taxes and other income, net. NOTE 13. NET LOSS PER SHARE Basic net loss per share is calculated by dividing net loss by the weighted-average number of common shares outstanding during the period and excludes any dilutive effect of stock-based awards. Diluted net loss per common share is computed giving effect to all potential dilutive common shares, including common stock issuable upon exercise of stock options, unvested restricted stock units and ESPP shares issuable pursuant to the current purchase period. As we had net losses for the three months ended March 31, 2026 and 2025, all potential common shares were determined to be anti-dilutive during those periods. The following table sets forth the computation of net loss per common share: Three Months Ended March 31, (in thousands, except per share amounts) 2026 2025 Numerator Net loss $ ( 37,605 ) $ ( 41,144 ) Denominator Weighted average common shares outstanding - basic and diluted 245,855 238,624 Net loss per share of common stock - basic and diluted $ ( 0.15 ) $ ( 0.17 ) 15 Table of Contents The total numbers of securities that could potentially dilute net income per share in the future that were not considered in the diluted net loss per share calculations because the effect would have been anti-dilutive were as follows: Three Months Ended March 31, (in thousands) 2026 2025 Options to purchase common stock 29,708 29,129 Restricted stock units 15,467 10,370 ESPP shares issuable 146 213 Total 45,321 39,712 NOTE 14. COMMITMENTS AND CONTINGENCIES On December 7, 2021 and March 29, 2022, two verified shareholder derivative lawsuits were filed in the U.S. District Court for the Northern District of California purportedly on behalf of Ardelyx against certain of Ardelyx’s executive officers and members of our board of directors, captioned Go v. Raab, et al., Case No. 4:21-cv-09455-HSG, and Morris v. Raab, et al., Case No. 4:22-cv-01988-JSC (together, the Go and Morris actions). The complaints allege that the defendants’ violations of Section 14(a) of the Exchange Act, breaches of fiduciary duties, unjust enrichment, abuse of control, gross mismanagement, and waste of corporate assets for personally making and/or causing Ardelyx to make materially false and misleading statements regarding the Company’s business, operations and prospects. The complaint seeks contribution under Sections 10(b) and 21D of the Exchange Act from two executive officers. On January 19, 2022 and April 27, 2022, the court granted the parties’ stipulation to stay the Go and Morris actions, respectively, until resolution of the motion(s) to dismiss in the lawsuits captioned Strezsak v. Ardelyx, Inc., et al., Case No. 4:21-cv-05868-HSG and Siegel v. Ardelyx, Inc., et al., Case No. 5:21-cv-06228-HSG (together, the Securities Class Actions). On October 25, 2022, the parties filed a stipulation to consolidate and stay the Go and Morris actions, and on October 27, 2022, the court consolidated the Go and Morris actions and stayed the consolidated action pending resolution of the anticipated motion(s) to dismiss in the Securities Class Action. The Securities Class Actions were voluntarily dismissed on March 5, 2025. The court dismissed the Go and Morris actions on April 30, 2025. On July 17, 2024, in partnership with the AAKP and the NMQF, we filed a lawsuit in the U.S. District Court for the District of Columbia against CMS, claiming that CMS has violated its statutory and regulatory authority under MIPPA, which established the ESRD PPS bundled payment system for dialysis services in 2008. Specifically, the lawsuit claims that moving XPHOZAH, along with all oral-only drugs, into the ESRD PPS is inconsistent with MIPPA’s statutory provision, and contradicts CMS’s own regulations. XPHOZAH and other oral-only drugs are not administered by dialysis providers and cannot be taken during the delivery of maintenance dialysis. On November 8, 2024, the U.S. District Court for the District of Columbia granted defendants’ Motion to Dismiss and denied plaintiffs’ Motion for Preliminary Injunction, or in the Alternative, for Expedited Summary Judgment. Following the District Court’s denial of plaintiffs’ Motion to Alter or Amend the Judgment, or in the Alternative, for an Injunction Pending Appeal, plaintiffs filed an Emergency Motion for an Administrative Stay and Injunction Pending Appeal, which was denied by the United States Court of Appeals for the District of Columbia Circuit. Appellants filed an initial brief in the appeal on February 4, 2025; Appellees filed an initial brief on March 6, 2025; and Appellants filed a reply brief on March 27, 2025. Both Appellees and Appellants filed a final brief on April 10, 2025. Oral argument in the case was heard on September 25, 2025. On August 16, 2024, a complaint was filed against us in the U.S. District Court of Massachusetts, captioned Yarborough v. Ardelyx, Inc., et al., No. 24-cv-12119 (D. Mass.). The complaint names the Company, Michael Raab, and Justin Renz as defendants and alleges violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder, related to our announcement on July 2, 2024 that it had chosen not to file an application for Transitional Drug Add-on Payment Adjustment for XPHOZAH (the Yarborough Action). The plaintiffs seek damages and interest, and an award of costs, including attorneys’ fees. The Court appointed Tate Wood as lead plaintiff on October 30, 2024. The lead plaintiff filed an amended complaint on January 13, 2025, in which he added Susan Rodriguez, Laura Williams and Elizabeth Grammer as additional defendants and removed Justin Renz as a defendant. The lead plaintiff purports to bring claims on behalf of all those who acquired Ardelyx common stock between February 22, 2024 and July 1, 2024. Defendants filed a motion to dismiss the amended complaint on March 14, 2025. Plaintiffs filed a response on May 13, 2025. Defendants filed a reply in support of their motion to dismiss on June 23, 2025. A hearing on the motion to dismiss was held on September 25, 2025, and on December 24, 2025, the Court granted defendants’ motion to dismiss and issued an order dismissing the case with prejudice. On January 21, 2026, Plaintiffs appealed the District Court’s decisions to the United States Court of Appeals for the First Circuit. On March 26, 2026, the Court granted the Parties’ stipulated voluntary dismissal of Plaintiffs’ appeal. On September 6 and 13, 2024, certain Ardelyx shareholders filed two verified derivative complaints purportedly on behalf of the Company in the United States District Court for the District of Massachusetts alleging violations of Sections 10(b) and/or 14(a) of the Exchange Act, breaches of fiduciary duty, unjust enrichment, waste, and aiding and abetting breaches of fiduciary 16 Table of Contents duty against certain members of our board of directors and management based on substantially the same factual allegations in the Yarborough Action. The complaints seek unspecified damages and corporate governance reforms, as well as costs and attorneys’ fees. On September 25, 2024, the Court consolidated the two derivative actions into the case In re Ardelyx, Inc. Stockholder Derivative Litigation, Case No. 1:24-cv-12302-LTS (D. Mass.). On November 7, 2024, the Court stayed the consolidated derivative action pending resolution of any and all motion(s) to dismiss in the Yarborough Action. On April 9, 2026, the Court dismissed the consolidated derivative action pursuant to the parties’ stipulation of dismissal. From time to time, we may be involved in legal proceedings arising in the ordinary course of business. As of March 31, 2026, there is no litigation pending that would reasonably be expected to have a material adverse effect on our results of operations and financial condition. NOTE 15. SUBSEQUENT EVENTS On April 28, 2026, we entered into an amendment to our 2022 Loan Agreement (the Sixth Amendment), by and among the Company, as borrower, SLR, as collateral agent and the lenders party thereto. 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.