Relypsa Presents Sub-Group Analysis From Phase 3 Study of Patiromer FOS in Patients With Advanced Chronic Kidney Disease at 2015 National Kidney Foundation Spring Clinical Meeting

Phase 3 OPAL-HK Trial Primary Outcomes Previously Published in the New England Journal of Medicine


REDWOOD CITY, Calif., March 26, 2015 (GLOBE NEWSWIRE) -- Relypsa Inc. (Nasdaq:RLYP), a biopharmaceutical company, today announced that data from a Phase 3 clinical program showing that Patiromer for Oral Suspension (Patiromer FOS), the Company's lead product candidate, was effective in reducing potassium levels and preventing a recurrence of hyperkalemia in patients with advanced (stage 4-5) chronic kidney disease (CKD) receiving ongoing treatment with renin-angiotensin-aldosterone system (RAAS) inhibitors were presented today as a poster at the National Kidney Foundation 2015 Spring Clinical Meeting. The results are from a sub-group analysis of the two part Phase 3 trial, OPAL-HK, conducted under a Special Protocol Assessment (SPA) with the U.S. Food and Drug Administration (FDA) that was led by Matthew Weir, M.D., Professor and Director, Division of Nephrology, University of Maryland School of Medicine.

The Phase 3 OPAL-HK trial primary outcomes, previously published in the New England Journal of Medicine, were combined with results from Relypsa's broader clinical development program to support the Company's New Drug Application (NDA) for Patiromer FOS. The FDA has assigned a Prescription Drug User Fee Act (PDUFA) action date of October 21, 2015 for completion of the review of the NDA.

"The efficacy of Patiromer FOS in correcting hyperkalemia and preventing a recurrence demonstrated in this sub-group analysis reflects consistent trends observed in the full study, despite severely impaired renal function in a high risk patient population with multiple comorbidities," said Lance Berman, M.D., chief medical officer of Relypsa. "RAAS inhibitor therapy is an important treatment option for preventing progression of renal disease, and treatment of hypertension in patients with severe CKD, however the risks of hyperkalemia have limited their use. The data from this sub-analysis of the OPAL-HK study suggest that a greater number of stage 4-5 CKD patients on Patiromer FOS may be able to remain on RAAS inhibitor therapy than those on placebo. If approved, Patiromer FOS may represent a new treatment option for controlling hyperkalemia in these patients while simultaneously managing their CKD."

Poster #240, entitled "Patiromer Reduced Recurrent Hyperkalemia in Patients With Advanced CKD on RAAS Inhibitors: Results From the Randomized Phase 3 OPAL-HK Study," reports that a statistically significant reduction in potassium levels from baseline were observed in 106 patients with stage 4-5 CKD treated with Patiromer FOS during an initial four week treatment phase.

Baseline demographics include estimated glomerular filtration rate (eGFR) levels of 21.3 mL/min/1.73m2, 62 percent of patients with type 2 diabetes, 97 percent with hypertension, and 23 percent with a history of myocardial infarction. Patients had mean Charlson Comorbidity Index (CCI) score of 6.5, consistent with a significant disease burden and high mortality risk. All patients were receiving RAAS inhibitor therapy, including 40 percent at investigator-determined maximal dose.

At the conclusion of the four week treatment phase, 72 percent of patients had potassium levels within a normal target range. Following the treatment phase, eligible patients underwent an eight week placebo-controlled withdrawal phase in which 69 percent of placebo patients had at least one recurrent hyperkalemia event (serum potassium ≥ 5.5 mEq/L) versus 20 percent of Patiromer FOS patients. Additionally, in a prespecified exploratory analysis, 65 percent of placebo patients required an adjustment or discontinuation of RAAS inhibitor therapy due to hyperkalemia during the withdrawal phase as compared to 14 percent of patients treated with Patiromer FOS. Mean levels of calcium and magnesium consistently remained within normal ranges in patients treated throughout both phases of the study. Overall, Patiromer FOS was well tolerated, with a low rate of discontinuations due to adverse events and a low rate of hypokalemia. The Phase 3 OPAL-HK trial primary outcomes were previously published in the New England Journal of Medicine.

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 FOS is an 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 program, a 12-month Phase 2 trial and a 48-hour Phase 1 onset-of-action trial. In all of those trials, Patiromer FOS met its efficacy endpoints and the treatment was well tolerated. The pivotal clinical trial 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. A New Drug Application for Patiromer for Oral Suspension for the treatment of hyperkalemia was accepted by the U.S. Food and Drug Administration and is currently under review. 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 potential approval of Patiromer for Oral Suspension, or Patiromer FOS, the efficacy of Patiromer FOS in correcting hyperkalemia and preventing a recurrence, the importance of renin-angiotensin-aldosterone-system, or RAAS, inhibitor therapy for patients with severe chronic kidney disease, or CKD, and the risks of hyperkalemia limiting the use of RAAS inhibitor therapy, the potential of Patiromer FOS to enable stage 4-5 CKD patients to remain on RAAS inhibitor therapy, the potential of Patiromer FOS to enable these patients to control hyperkalemia while simultaneously managing their CKD. Such forward-looking statements involve substantial risks and uncertainties that could cause our clinical development program, future results, performance or achievements to 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 Relypsa's regulatory filings, Relypsa's substantial dependence on Patiromer FOS, Relypsa's 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 Relypsa in general, see Relypsa's current and future reports filed with the U.S. Securities and Exchange Commission, including its Annual Report on Form 10-K for the year ended December 31, 2014.



            

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