Akebia Therapeutics Reports Fourth Quarter and Full-Year 2022 Financial Results and Recent Business Highlights Akebia to host conference call on March 9 at 8:30 a.m. ET Receives positive CHMP opinion for Vafseo (vadadust

Akebia Therapeutics Reports Fourth Quarter and Full-Year 2022 Financial Results and

Recent Business Highlights

Akebia to host conference call on March 9 at 8:30 a.m. ET

CAMBRIDGE, Mass. March 9, 2023 Akebia Therapeutics , Inc.

(Nasdaq: AKBA), a biopharmaceutical company with the purpose to better the lives of people impacted by kidney disease, today reported financial results for the fourth quarter and full-year ended December 31, 2022 and provided business

We ended our year delivering on our strategic focus, which included a commitment to maximize Auryxia revenue, support vadadustat

globally and thoughtfully invest in our pipeline, said John P. Butler, Chief Executive Officer of Akebia. We believe the work our team executed through the fourth quarter and more broadly in 2022 has put us in a strong position as we

prepare for several meaningful upcoming milestones. Building on our positive CHMP opinion for vadadustat in Europe, we anticipate potential Marketing Authorization of Vafseo by the European Commission in May 2023, and we are active in our process to

select a partner in Europe to deliver Vafseo to patients with chronic kidney disease (CKD) on dialysis, if approved.

announced that the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion recommending the European Commission (EC) to approve

Vafseo (vadadustat), for the treatment of symptomatic anaemia associated with CKD in adults on chronic maintenance dialysis. If approved, an EC Marketing Authorization of Vafseo would be

applicable to all 27 European Union member states plus Iceland, Norway and Liechtenstein. Akebia is seeking a partner to commercialize vadadustat in Europe.

Additionally, Akebia had an important year with several key milestones in 2022 and into early 2023:

Pipeline Progress Expected in 2023

continues to fund our business, and we entered 2023 with a robust operating plan, including funding for several compelling pipeline opportunities, said David A. Spellman, Chief Financial Officer of Akebia. Regarding revenue, we reported

nearly 25% net product revenue growth for Auryxia over 2021, which exceeded guidance. The fourth quarter of 2022 included an inventory build of approximately $3M year over year. We have set 2023 net product revenue guidance at $175-180 million as we remain cautious about a phosphate binder market recovery; the market continues to contract modestly due to COVID-19 and dialysis staffing issues.

We will continue to be mindful of non-essential spend and work to reduce costs overall.

Akebia will host a conference call on

Thursday, March 9 at 8:30 a.m. ET to discuss its financial results and recent business highlights. To access the call, please register by clicking on this Registration Link, and then you will be provided with dial in details. To avoid

delays, we encourage dialing into the conference call fifteen minutes ahead of the scheduled start time.

A live webcast of the conference call will be

available via the Investors section of Akebia s website at: https://ir.akebia.com/. An online archive of the webcast can be accessed via the Investors section of Akebia s website at http://ir.akebia.com approximately two hours after the

About Akebia Therapeutics

Therapeutics, Inc. is a fully integrated biopharmaceutical company with the purpose to better the lives of people impacted by kidney disease. Akebia was founded in 2007 and is headquartered in Cambridge, Massachusetts. For more information, please

visit our website at www.akebia.com, which does not form a part of this release.

Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor designed to mimic the physiologic effect of altitude on oxygen availability. At

higher altitudes, the body responds to lower oxygen availability with stabilization of hypoxia-inducible factor, which can lead to increased red blood cell production and improved oxygen delivery to tissues. Vadadustat is an

investigational new drug and is not approved by the U.S. Food and Drug Administration (FDA). On March 29, 2022, the FDA issued a complete response letter to Akebia s New Drug

Application for vadadustat for the treatment of anemia due to chronic kidney disease (CKD). Vadadustat is currently under review by the European Medicines Agency for the treatment of anemia due to CKD in adults. In Japan, vadadustat is approved as a

treatment for anemia due to CKD in both dialysis-dependent and non-dialysis dependent adult patients.

IMPORTANT U.S. SAFETY INFORMATION FOR AURYXIA (ferric citrate) CONTRAINDICATION

AURYXIA (ferric citrate) is contraindicated in patients with iron overload syndromes, e.g., hemochromatosis.

WARNINGS AND PRECAUTIONS

Most common adverse reactions with

SPECIFIC POPULATIONS

adverse reactions, contact Akebia Therapeutics at 1-844-445-3799.

Please see full Prescribing Information

Forward-Looking Statements

Statements in this press release regarding Akebia Therapeutics, Inc. s ( Akebia s ) strategy, plans, prospects, expectations, beliefs,

intentions and goals are forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995, as amended, and include, but are not limited to, statements regarding: Akebia s plans, strategies and prospects

for its business, including with respect to the FDRR that Akebia submitted with the FDA to appeal the Complete Response Letter that it received in March 2022; Akebia s expectations on the timing for certain regulatory decisions for vadadustat

by the FDA and regulatory authorities in the U.K., Switzerland and Australia; Akebia s expectations on the timing of a decision from the European Commission and, if approved, Akebia s plans with respect to commercializing and identifying a

partner for vadadustat in Europe; Akebia s expectations with respect to certain development activities and the timing of those activities, including the initiation of a trial to study vadadustat for the treatment of ARDS; Akebia s future

plans with respect to its strategic growth and operating plans; Akebia s revenue guidance for Auryxia in 2023 and assumptions related thereto; Akebia s plans with respect to vadadustat as a treatment of anemia due to CKD in patients on

dialysis; and Akebia s goals, objectives and expectations with respect to its operating plan, expenses, cash resources and sources of funding for its cash runway, including its belief that its existing cash resources and revenues from Auryxia

will be sufficient to fund its current operating plan for at least the next twelve months. The terms intend, believe, plan, goal, expect, potential, will,

continue, derivatives of these words, and similar references are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results, performance or experience may

differ materially from those expressed or implied by any forward-looking statement as a result of various risks, uncertainties and other factors, including, but not limited to, risks associated with: the potential demand and market potential and

acceptance of, as well as coverage and reimbursement related to, Auryxia, including estimates regarding the potential market opportunity; the competitive landscape for Auryxia, including potential generic entrants; the ability of Akebia to attract

and retain qualified personnel; Akebia s ability to implement cost avoidance measures and reduce operating expenses; decisions made by health authorities, such as the FDA and the European Medicines Agency, with respect to regulatory filings,

including the New Drug Application and the FDRR for vadadustat; Akebia s ability to partner for vadadustat in Europe in a timely manner, on acceptable terms, or at all; the potential therapeutic benefits, safety profile, and effectiveness of

vadadustat; the results of preclinical and clinical research; the direct or indirect impact of the COVID-19 pandemic on regulators and Akebia s business, operations, and the markets and communities in

which Akebia and its partners, collaborators, vendors and customers operate; manufacturing, supply chain and quality matters and any recalls, write-downs, impairments or other related consequences or potential consequences; and early termination of

any of Akebia s collaborations. Other risks and uncertainties include those identified under the heading Risk Factors in Akebia s Quarterly Report on Form 10-Q for the quarter ended

September 30, 2022, and other filings that Akebia may make with the U.S. Securities and Exchange Commission in the future. These forward-looking statements (except as otherwise noted) speak only as of the date of this press release, and, except

as required by law, Akebia does not undertake, and specifically disclaims, any obligation to update any forward-looking statements contained in this press release.

Akebia Therapeutics , Auryxia (ferric citrate), and Vafseo (vadadustat) are registered trademarks of Akebia Therapeutics, Inc. and its affiliates.

Akebia Therapeutics Contact

AKEBIA THERAPEUTICS,

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AKEBIA THERAPEUTICS, INC.

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