Relypsa Announces Assignment of October 21, 2015 PDUFA Date for New Drug Application for Patiromer for Oral Suspension

FDA Not Currently Planning to Hold an Advisory Committee Meeting
Company to Host Webcasted Analyst Day in New York on January 8, 2015

REDWOOD CITY, Calif., Jan. 5, 2015 (GLOBE NEWSWIRE) — Relypsa, Inc. (Nasdaq:RLYP), today announced that the U.S. Food and Drug Administration (FDA) has assigned a Prescription Drug User Fee Act (PDUFA) action date of October 21, 2015 for completion of the review of the New Drug Application (NDA) for the investigational agent Patiromer for Oral Suspension (Patiromer FOS) for the treatment of hyperkalemia, a serious condition defined as abnormally elevated levels of potassium in the blood. The company had announced on December 15, 2014 that the FDA accepted the Patiromer FOS NDA for review. In the day-74 letter to Relypsa, the FDA further indicated that it does not currently plan to convene an Advisory Committee for advice on the company’s NDA.

If approved, Patiromer FOS is expected to be the first new therapeutic made available for the treatment of hyperkalemia in over 50 years.

“There are limited options for the treatment of hyperkalemia, a condition that affects many people with chronic kidney disease and heart failure and may be further exacerbated in patients on renin-angiotensin-aldosterone-system (RAAS) inhibitors,” said John A. Orwin, president and chief executive officer of Relypsa. “We are pleased that the NDA is considered filed by FDA and look forward to potentially offering patients and physicians a new treatment option that has been evaluated in acute and chronic settings.”

The NDA is supported by eight clinical trials, including a Phase 3 program that was conducted under a Special Protocol Assessment, a long-term treatment trial that evaluated the safety and efficacy of Patiromer FOS in patients for up to one year, and an onset-of-action study that evaluated the time to potassium lowering action.

The company also announced that it will host and webcast an Analyst Day to be held in New York on Thursday, January 8, 2015 at 9:00 a.m. ET. Interested parties may access the live webcast and subsequent archived recording by visiting the Investor Events section of Relypsa’s website at www.relypsa.com.

About Hyperkalemia
Hyperkalemia, a serious condition defined as abnormally elevated levels of potassium in the blood, is frequently prevalent in patients who suffer from chronic kidney disease, hypertension, diabetes and/or heart failure. Hyperkalemia can lead to life-threatening cardiac arrhythmia and sudden death. Patients with chronic kidney disease or heart failure are at particular risk for developing hyperkalemia, especially those treated with renin-angiotensin-aldosterone-system (RAAS) inhibitors such as ARBs (Angiotensin Receptor Blockers), AAs (Aldosterone Antagonists), and ACE (Angiotensin-Converting-Enzyme) inhibitors. Although RAAS inhibition has been shown to protect kidney and cardiac function, many patients who could benefit from RAAS inhibitors are untreated or undertreated due to the undesirable side effect of increasing serum potassium.

About Patiromer FOS
Patiromer for Oral Suspension is a high capacity, oral potassium binder being developed for the treatment of hyperkalemia. The compound has been evaluated in CKD patients with hyperkalemia, including a two part Phase 3 study, a 12-month Phase 2 trial and a 48-hour Phase 1 onset-of-action study. In all of those studies, Patiromer FOS met its efficacy endpoints and the treatment was well tolerated. The pivotal clinical study for Patiromer FOS was conducted under a Special Protocol Assessment with the FDA.

About Relypsa, Inc.
Relypsa, Inc. is a biopharmaceutical company focused on the development and commercialization of non-absorbed polymeric drugs to treat disorders in the areas of renal, cardiovascular and metabolic diseases. The company’s two-part pivotal Phase 3 trial of its lead product candidate, Patiromer for Oral Suspension, for the treatment of hyperkalemia, a potentially life-threatening condition defined as abnormally elevated levels of potassium in the blood, has been completed and the primary and secondary endpoints were met. Relypsa has global royalty-free commercialization rights to Patiromer for Oral Suspension, which has intellectual property protection in the U.S. until at least 2030. More information is available at www.relypsa.com.

Forward Looking Statements
To the extent that statements contained in this press release are not descriptions of historical facts regarding Relypsa, they are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, including statements regarding the anticipated Prescription Drug User Fee Act goal date, the current plan of the U.S. Food and Drug Administration, or FDA, not to convene an Advisory Committee, the limited options for the treatment of hyperkalemia, the potential FDA approval of Patiromer for Oral Suspension, or Patiromer FOS, and the therapeutic and commercial potential of the drug. Such forward-looking statements involve substantial risks and uncertainties that relate to future events and the actual results could differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, the uncertainties inherent in the clinical drug development process, including the regulatory approval process, the timing of the company’s regulatory filings, the company’s substantial dependence on Patiromer FOS, its commercialization plans and efforts and other matters that could affect the availability or commercial potential of Patiromer FOS. Relypsa undertakes no obligation to update or revise any forward-looking statements. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the business of the company in general, see the company’s current and future reports filed with the U.S. Securities and Exchange Commission, including its Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2014.

Contact
Sylvia Wheeler
V.P., Investor Relations and Corporate Affairs
650 421 9504
IR @relypsa.com