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EX-99.1

2 ardx-20260331xexhibit991.htm

EX-99.1

Document

Exhibit 99.1

Ardelyx Reports First Quarter 2026 Financial Results and Provides Business Update

Q1 2026 total product revenue of $93.4 million, reflecting 38% growth year-over-year

IBSRELA Q1 2026 revenue growth of 58% year-over-year to $70.1 million; Reiterating guidance of $410-$430 million

Strong financial position with $238.1 million in cash, cash equivalents and investments as of March 31, 2026

Conference call scheduled for 4:30 PM Eastern Time

WALTHAM, Mass., April 30, 2026 – Ardelyx Inc. (Nasdaq: ARDX), (“Ardelyx” or the “Company”) a commercial-stage biopharmaceutical company focused on the development and commercialization of innovative medicines that meet significant unmet medical needs, today reported financial results for the first quarter ended March 31, 2026, and provided a business update.

“In the first quarter of 2026, Ardelyx continued our strong commercial execution which coupled with our strengthening cash position allows us to conduct multiple IBSRELA clinical trials, advance development of our next-generation NHE3 inhibitor, RDX10531, and purposefully explore various avenues to build a significant and sustainable pipeline of important medicines,” said Mike Raab, President and Chief Executive Officer of Ardelyx. “IBSRELA is the cornerstone for the company we’re building and is on the path to becoming a blockbuster by achieving at least one billion dollars in revenue in 2029 with continued strong growth thereafter. We are in a position of financial strength, providing flexibility to allocate capital across the business, accelerate commercial momentum, and drive intrinsic long-term value for the Company, our patients, and our shareholders.”

Product Revenue

Revenue for IBSRELA® (tenapanor) during the first quarter of 2026 was $70.1 million, reflecting year-over-year growth of approximately 58%. The growth was driven by increases across key demand indicators, including total writers and new and refill prescriptions and continued improvement to prescription pull-through.

Revenue for XPHOZAH® (tenapanor) during the first quarter of 2026 was $23.3 million driven by a strong increase in paid prescriptions.

2026 Revenue Guidance

Ardelyx reiterates its full-year 2026 revenue guidance:

•IBSRELA revenue between $410.0 and $430.0 million

•XPHOZAH revenue between $110.0 and $120.0 million

Advancing a Pipeline of Important Medicines

•IBSRELA is being evaluated for the treatment of chronic idiopathic constipation (CIC) in adults in a Phase 3 clinical trial, ACCEL. In January 2026, the Company dosed the first patient in ACCEL and has initiated all pre-identified sites. The Company expects to complete enrollment by the end of 2026 with topline data read out in the second half of 2027.

•IBSRELA is also being evaluated in multiple pediatric clinical trials which could potentially provide six months of additional patent life for tenapanor.

•RDX10531, the Company’s next-generation NHE3 inhibitor is currently being tested in IND-enabling studies. If successful, RDX10531 has potential for broad applications across multiple therapeutic areas.

Other Corporate Developments

•In February, Ardelyx announced a multi-year partnership with the LPGA to serve as an official corporate pharmaceutical marketing partner, focusing on digestive health education and patient empowerment throughout the 2026 season.

•In April, the Company expanded its executive leadership team with the appointment of Rajani Dinavahi, M.D. as Chief Medical Officer and Felecia W. Ettenberg, Esq. as Chief Legal Officer.

•In April, the Company and SLR Investment Corp refinanced their existing debt, resulting in better overall terms. Morgan Stanley & Co. LLC acted as financial advisor to Ardelyx.

•The Company’s abstracts containing additional tenapanor data were accepted for poster presentations at the upcoming Digestive Disease Week conference (May 2-5, 2026) and National Kidney Foundation’s Spring Clinical Meeting (May 6-10, 2026).

First Quarter 2026 Financial Results

•    Cash Position: As of March 31, 2026, the Company had total cash, cash equivalents and short-term investments of $238.1 million, compared to total cash, cash equivalents and short-term investments of $264.7 million as of December 31, 2025.

•    Revenues: Total product revenue for the quarter ended March 31, 2026 was $93.4 million, compared to $67.8 million for the quarter ended March 31, 2025, reflecting 38% growth, driven by increased demand.

•    R&D Expenses: Research and development expenses were $20.2 million for the quarter ended March 31, 2026, compared to $14.9 million for the quarter ended March 31, 2025. The increase was primarily related to investments in the ACCEL Phase 3 trial for CIC.

•    SG&A Expenses: Selling, general and administrative expenses were $102.3 million for the quarter ended March 31, 2026, compared to $83.2 million for the quarter ended March 31, 2025. The increase was re

ardx-202602190001437402false00014374022026-02-192026-02-19

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 19, 2026

ARDELYX, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3648526-1303944 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification Number)

400 FIFTH AVE., SUITE 210, WALTHAM, MASSACHUSETTS 02451

(Address of principal executive offices, including Zip Code) Registrant’s telephone number, including area code: (510) 745-1700

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.0001 per shareARDXThe Nasdaq Global Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company  ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  o

Item 2.02    Results of Operations and Financial Condition. On February 19, 2026, Ardelyx, Inc. (the “Company”) announced its financial results for the quarter and year ended December 31, 2025. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K. The information furnished under this Item 2.02, including Exhibit 99.1 hereto, shall not be considered “filed” under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), nor shall it be incorporated by reference into any future filing under the Securities Act of 1933, as amended (the “Securities Act”), or under the Exchange Act, unless the Company expressly sets forth in such future filing that such information is to be considered “filed” or incorporated by reference therein.

Item 7.01    Regulation FD Disclosure.

On February 19, 2026, the Company will host a conference call to discuss its financial results for the quarter and year ended December 31, 2025. A copy of the earnings presentation that will be used during this conference call is furnished as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated herein by reference. The information furnished under this Item 7.01, including Exhibit 99.2 hereto, shall not be considered “filed” under the Exchange Act nor shall it be incorporated by reference into any future filing under the Securities Act, or under the Exchange Act, unless the Company expressly sets forth in such future filing that such information is to be considered “filed” or incorporated by reference therein.

Item 9.01    Financial Statements and Exhibits. (d) Exhibits.

Exhibit No. Description 99.1Press Release of Ardelyx, Inc.

99.2Earnings Presentation of Ardelyx, Inc.

104Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: February 19, 2026ARDELYX, INC.

By:/s/ Susan Hohenleitner Susan Hohenleitner Chief Financial Officer