ARDELYX, INC. (ARDX)

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

You should read the following discussion and analysis of our financial condition and results of operations in conjunction with the condensed financial statements and notes thereto included elsewhere in this report and with the audited financial statements and related notes thereto included as part of our 2025 Form 10-K. This discussion and analysis and other parts of this report contain forward-looking statements that involve risk and uncertainties, such as statements of our plans, objectives, expectations and intentions. Our actual results could differ materially from those discussed in these forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, those discussed in the section of this report titled “Risk Factors.” These forward-looking statements speak only as of the date hereof. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason. Unless the context requires otherwise, the terms “Ardelyx,” “Company,” “we,” “us” and “our” refer to Ardelyx, Inc.

EXECUTIVE SUMMARY

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, an 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. In addition, we are building a pipeline which is currently focused on expanding the commercial footprint of tenapanor.

We are committed to our mission of developing and commercializing innovative medicines that address unmet patient needs. Our principal strategy is to continue our commercial momentum with our current products while advancing and expanding a portfolio of important medicines for patients with unmet medical needs.

Our priorities include (i) driving significant IBSRELA growth, (ii) maintaining XPHOZAH commercial momentum, (iii) further advancing our pipeline and portfolio and (iv) maintaining a solid financial foundation to support our future growth.

Tenapanor, branded as IBSRELA®, is approved in the U.S. for the treatment of adults with IBS-C. We believe that IBSRELA can bring meaningful benefit to the approximately 13 million Americans who suffer from the symptoms of IBS-C, many of whom continue to experience symptoms despite intervention with other therapies. We are seeking to further expand the IBSRELA eligible patient population to include patients with CIC, and have initiated a Phase 3 clinical trial (ACCEL) evaluating tenapanor in adults with CIC. In January 2026, we dosed the first patient in ACCEL and have initiated all pre-identified sites. We expect to complete enrollment by the end of 2026 and to announce topline data in the second half of 2027. IBSRELA is also being evaluated in multiple pediatric clinical trials which could expand its use and potentially provide six months of additional patent life for tenapanor.

Tenapanor, branded as XPHOZAH®, is approved in the U.S. to reduce serum phosphorus in adults with CKD 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 believe XPHOZAH can bring meaningful relief to adult CKD patients on dialysis, the vast majority of whom have elevated levels of serum phosphorus and are unable to achieve target serum phosphorus levels with phosphate binders alone. Continually elevated levels of serum phosphorus can result in severe cardiovascular health complications.

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. RDX10531 is currently being tested in IND-enabling studies. If successful, RDX10531 has potential for broad applications across multiple therapeutic areas.

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Effective April 28, 2026, we entered into the Sixth Amendment to our Loan Agreement with SLR as collateral agent and the lenders party thereto, resulting in better overall terms.

On June 26, 2026, the U.S. Court of Appeals for the District of Columbia Circuit affirmed the District Court’s dismissal of our lawsuit against CMS related to CMS reimbursement classification of XPHOZAH. We are not pursuing further litigation on this matter.

On June 29, 2026, we received $50.0 million of funding as a result of our draw down of the Term F Loan. We elected to draw down the Term F Loan for general corporate purposes and to enhance flexibility to support our ongoing strategic initiatives, in line with our capital allocation strategy.

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.

RESULTS OF OPERATIONS

The results of operations for the three and six months ended June 30, 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. See Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” of our 2025 Form 10-K to enhance the understanding of our financial metrics below.

Revenues

Below is a summary of our total revenues:

Below is a summary of our product sales, net by product:

Product sales, net:

The increase in IBSRELA product sales, net in the three and six months ended June 30, 2026 primarily reflected higher demand, driven by continued increase in awareness and prescriber experience, and to a lesser extent, higher net price.

The increase in XPHOZAH product sales, net in the three and six months ended June 30, 2026 primarily reflected higher demand and net price. XPHOZAH product sales, net in the six months ended June 30, 2025 included a $3.8 million favorable adjustment driven by a change in previously estimated product returns.

Product supply revenue:

Product supply revenue is primarily impacted by the timing of product supply shipments to our collaboration partners under our product supply agreements in support of the development and commercialization of our products ex-U.S. by our collaboration partners.

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The product supply revenue was primarily attributable to Fosun Pharma in the three and six months ended June 30, 2026. In the three and six months ended June 30, 2025, the product supply revenue was primarily attributable to Kyowa Kirin.

Licensing revenue:

Licensing revenue is primarily impacted by the timing of regulatory and commercialization milestone achievements as well as sales-based royalties received from our collaboration partners.

The licensing revenue was primarily attributable to sales-based royalties received from Fosun Pharma in the three and six months ended June 30, 2026. The licensing revenue in the six months ended June 30, 2025 included a $5.0 million milestone earned in the 2025 first quarter under the terms of the Fosun Agreement, following 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.

Non-cash royalty revenue:

The decrease in non-cash royalty revenue in the three and six months ended June 30, 2026 reflected lower royalties received from Kyowa Kirin for sales of PHOZEVEL in Japan.

GTN Adjustments

Reconciliation of gross product sales to product sales, net is as follows:

The increase in GTN adjustment percentage in the three and six months ended June 30, 2026 primarily reflected an unfavorable channel mix as well as Medicare and Medicaid Inflation Rebate charges.

The increase in GTN adjustment percentage in the six months ended June 30, 2026 reflected a $3.8 million favorable adjustment recognized in the 2025 first quarter, which was driven by a change in previously estimated XPHOZAH product returns.

The activities and ending reserve balances for each significant category of GTN adjustments on product sales, net, which constitute variable consideration, were as follows:

(1)Adjustments to prior period provisions recorded in the current period were not material.

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Costs and Expenses

Below is a summary of our costs and operating expenses, interest expense, non-cash interest expense related to the sale of future royalties and other income, net:

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

You should read the following discussion and analysis of our financial condition and results of operations in conjunction with our financial statements and related notes included elsewhere in this report. This discussion and other parts of this report contain forward-looking statements that involve risk and uncertainties, such as statements of our plans, objectives, expectations and intentions. Our actual results could differ materially from those discussed in these forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, those discussed in the section of this report titled “Risk Factors.” These forward-looking statements speak only as of the date hereof. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason. Unless the context requires otherwise, the terms “Ardelyx,” “Company,” “we,” “us” and “our” refer to Ardelyx, Inc.

EXECUTIVE SUMMARY AND FINANCIAL HIGHLIGHTS

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, an 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, first-in-class, oral, small molecule therapy.

Tenapanor, branded as IBSRELA®, is approved in the U.S. for the treatment of adults with irritable bowel syndrome with constipation. We believe that IBSRELA can bring meaningful benefit to the approximately 13 million Americans who suffer from the symptoms of IBS-C, many of whom continue to experience symptoms despite intervention with other therapies. We are seeking to further expand the IBSRELA eligible patient population to include patients with 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 believe XPHOZAH can bring meaningful relief to adult chronic kidney disease patients on dialysis, the vast majority of whom have elevated levels of serum phosphorus and are unable to achieve target serum phosphorus levels with phosphate binders alone. Continually elevated levels of serum phosphorus can result in severe cardiovascular health complications.

In addition to commercializing IBSRELA and XPHOZAH, we are also developing a next-generation NHE3 inhibitor that we believe can have application across multiple therapeutic areas.

Refer to the Summary of Abbreviated Terms at the end of this Annual Report on Form 10-K for definitions of terms used throughout the document.

We are committed to our mission of developing and commercializing innovative medicines that address unmet patient needs. Our principal strategy is to continue our commercial momentum with our current products while advancing and expanding a portfolio of important medicines for patients with unmet medical needs.

Our priorities include (i) driving significant IBSRELA growth, (ii) maintaining XPHOZAH commercial momentum, (iii) further advancing our pipeline and portfolio and (iv) maintaining a solid financial foundation to support our future growth.

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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 under the terms of the Fosun Agreement, which was recorded as licensing revenue on our statements of operations and comprehensive loss when earned during the 2025 first quarter and was received in April 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 under the AstraZeneca Termination Agreement.

On June 30, 2025, we entered into an amendment to our 2022 Loan Agreement (the Fifth Amendment), by and among the Company, as borrower, SLR, as collateral agent and the lenders party thereto. The Fifth Amendment, among other things, (i) provided for the immediate draw of $50.0 million of the Term E Loan on the closing date of the Fifth Amendment; and (ii) provides us with the option to draw an additional $100.0 million of committed senior secured term loans, consisting of the Term F Loan and the Term G Loan, each in the amount of $50.0 million. The Term F Loan and the Term G Loan may be drawn at the Company’s election by June 30, 2026 and December 20, 2026, respectively.

In September 2025, we submitted an IND application to the FDA for IBSRELA to expand the IBSRELA eligible patient population to include patients with CIC. In January 2026, we initiated ACCEL (ten-03-301), a Phase 3 clinical trial designed to assess the safety and efficacy of tenapanor for the treatment of CIC. Enrollment in ACCEL is expected throughout 2026, with topline data read out in the second half of 2027. CIC is characterized by difficult, infrequent or incomplete bowel movements, and is associated with significantly impaired quality of life, disrupted productivity and high healthcare-related costs. CIC is estimated to affect more than 34 million Americans. Pending the outcome of the Phase 3 clinical trial, if successful, we intend to submit a supplemental NDA to the FDA for tenapanor for the CIC indication.

In October 2025, we announced a development program for RDX10531. We believe RDX10531 is a next-generation NHE3 inhibitor with potential application across multiple therapeutic areas. We are currently conducting activities to support an IND submission to the FDA for RDX10531 in the second half of 2026.

The 2023 Open Market Sales Agreement with Jefferies with respect to an “at-the-market offering” program which was established under the Company’s prior shelf registration statement on Form S-3 expired in January 2026. In November 2025, we filed an automatic shelf registration statement on Form S-3ASR, along with a prospectus supplement relating to the offering and sale of up to $100.0 million of our common stock pursuant to the 2025 Open Market Sales Agreement with Jefferies, deemed to be “at-the-market offerings.” During the year ended December 31, 2025, we did not sell any shares under the 2023 or 2025 Open Market Sales Agreements.

On January 22, 2026, we received an Issue Notification from the USPTO indicating the issuance of U.S. Patent No. 12,539,299. The patent relates to the formulation of tenapanor and covers the commercial formulations of IBSRELA and XPHOZAH and has an expiration date of November 26, 2042.

Below is a summary of our product sales, net by product for the years ended December 31 and total cash, cash equivalents and short-term investments as of December 31:

RECENT ACCOUNTING PRONOUNCEMENTS

A summary of recent accounting pronouncements that we have adopted or expect to adopt is included in Note 2. Summary of Significant Accounting Policies in the notes to our financial statements, included in Part II, Item 8, of this Annual Report on Form 10-K.

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

A detailed discussion of our significant accounting policies can be found in Note 2. Summary of Significant Accounting Policies, in the notes to our financial statements, included in Part II, Item 8, of this Annual Report on Form 10-K. The preparation of financial statements requires the use of estimates and assumptions that affect the reported amounts of assets and liabilities and the reported amounts of revenues and expenses. Our critical accounting policies are those that significantly affect

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our financial condition and results of operations and require the most difficult, subjective or complex judgments, often because of the need to make estimates about the effect of matters that are inherently uncertain.

While we believe that our estimates, assumptions and judgments are reasonable, they are based on information presently available. Actual results may differ significantly from these estimates due to changes in judgments, assumptions or conditions as a result of unforeseen events or otherwise, which could have a material impact on our financial position and results of operations.

Revenue Recognition

The application of ASC 606 Revenue from Contracts with Customers substantially impacts our reported results, particularly product sales, net, which requires certain estimates in determining the transaction price. Total revenues are recognized following a five-step model: (i) identify the customer contract, (ii) identify the contract’s performance obligations, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations and (v) recognize revenue when or as a performance obligation is satisfied.

Product Sales, Net

Product revenue is recognized when Customers take control of the product, which typically occurs upon delivery to the Customers. The transaction price for product sales is reduced for estimates of variable consideration related to (i) discounts and chargebacks, (ii) rebates, wholesaler and GPO fees, and (iii) copay assistance and returns (collectively, gross-to-net adjustments or GTN adjustments). Except for certain wholesaler and GPO fees and discounts, which are based on contracts, our estimates of GTN adjustments involve assumptions and judgments. Our estimates of GTN adjustments for rebates, copay assistance and chargebacks require significant assumptions and judgments, considering factors such as legal interpretations of applicable laws and regulations, historical experience, payor mix (e.g., Medicare or Medicaid), current contract prices under applicable programs, unbilled claims, processing time lags and inventory levels in the distribution channel. Estimates are assessed each period and adjusted as required to revise information or actual experience.

Discounts and Chargebacks

Our U.S. business participates in programs with government entities, the most significant of which are the U.S. Department of Defense, the U.S. VA, and other parties, including covered entities under the 340B program, whereby pricing on products is extended below wholesale acquisition cost (lower program price) for qualified government providers when products are purchased through wholesalers. The chargeback represents the difference between the wholesale acquisition cost and this lower program price that the wholesalers charge us. In such sales, accounts receivable is reduced for the estimated amount of unprocessed chargeback claims (typically within a two- to four-week time lag).

Our Customers may receive prompt pay discounts for payment within a specified period, generally approximating two percent of the invoiced sales price. Our payment terms are generally 30 to 60 days. We expect discounts to be earned when offered and therefore deduct the full amount of these discounts from product sales when revenue is recognized. Accordingly, accounts receivable is reduced for the estimated amount of these discounts.

Rebates, Wholesaler and GPO Fees

Our U.S. business participates in state government Medicaid and Medic

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