Positive Phase 2 Data for RLY5016 Presented in Late-Breaker Session at Heart Failure Society of America Meeting

Positive Phase 2 Data for RLY5016 Presented in Late-Breaker Session at Heart Failure Society of America Meeting
Noted Cardiovascular Endocrinology Expert Mason Freeman, M.D., Joins Relypsa as Strategic Clinical Advisor for Development of RLY5016

SANTA CLARA, Calif.--(BUSINESS WIRE)--Relypsa, Inc., a biopharmaceutical company developing non-absorbed polymeric drugs, today announced positive results from the company's PEARL-HF study, a Phase 2 clinical trial of the company's lead compound, RLY5016. These data were presented by Dr. Bertram Pitt, Professor of Medicine Emeritus, Division of Medicine at the University of Michigan School of Medicine, during the Late-Breaking Clinical Trials Session in an oral presentation titled "The PEARL-HF (Multicenter, Randomized, Double-Blind, Placebo-Controlled, Parallel Group, Multiple-Dose To Evaluate the Effects of RLY5016 in Heart Failure Patients) Trial" at the 14th Annual Scientific Meeting of the Heart Failure Society of America held in San Diego, CA September 13-15, 2010.

PEARL-HF randomized heart failure patients who were already receiving one or more RAAS inhibitors (angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), or β-blockers) to 28 days treatment with RLY5016 or placebo. All patients were started on an aldosterone antagonist (spironolactone) on the same day as receiving their first dose of RLY5016. The study met its primary endpoint (mean change from baseline in serum potassium) and multiple secondary endpoints (including reduction of incidence of hyperkalemia and increased dose of spironolactone on RLY5016 versus placebo). In the entire study population, there was also a statistically significant three-fold difference favoring RLY5016 in the proportion of patients developing hyperkalemia compared to placebo. This difference was amplified in patients with chronic kidney disease (eGFR <60 mL/min). Consistent with findings from earlier studies, RLY5016 was safe and well tolerated.

In addition, Relypsa announced that Dr. Mason Freeman, Professor of Medicine, Harvard Medical School, an expert in cardiovascular endocrinology, has joined the company as a strategic clinical advisor for the ongoing development of RLY5016.

"Dr. Pitt's presentations on behalf of the PEARL-HF investigators at HFSA this week and at the European Society of Cardiology meeting in Stockholm in August underscore the potent potassium-lowering effects of RLY5016 and its potential utility for the cardiology and nephrology communities," commented Dr. Freeman. "RLY5016 has demonstrated its potential to manage serum potassium and thereby enable the optimal use of proven RAAS inhibitors in treating diabetic, chronic kidney disease and heart failure patients. I am excited by the data generated to date from this program and am pleased to be involved in helping Relypsa advance RLY5016 to pivotal studies."

About RLY5016 and Hyperkalemia

Hyperkalemia is a condition frequently prevalent in patients that suffer from renal impairment, hypertension, diabetes and heart failure. It is characterized by elevated serum potassium levels, which can lead to cardiac arrhythmia and sudden death. Heart failure patients are at particular risk for developing hyperkalemia, especially those with underlying chronic kidney disease treated with Renin-Angiotensin-Aldosterone-System (RAAS) inhibitors. RAAS inhibition in such patients provides a life-saving therapy, but has the undesirable side effect of increasing serum potassium.

RLY5016 is a high capacity non-absorbed oral potassium binder being developed for the chronic and acute management of elevated serum potassium levels. Relypsa has completed several clinical trials of RLY5016, including the PEARL-HF Phase 2 clinical trial, a multi-center, randomized, placebo-controlled study that assessed the efficacy, safety and tolerability of RLY5016 for the prevention of hyperkalemia in heart failure patients. A multi-center, open-label study to explore titration of RLY5016 is currently underway and is intended to inform pivotal study design.

About Relypsa, Inc.

Relypsa, Inc. is a, clinical-stage biopharmaceutical company leading the discovery and development of novel non-absorbed polymeric drugs for important applications in cardiovascular and renal diseases. Relypsa's lead product candidate is RLY5016, a non-absorbed potassium binder for the treatment of hyperkalemia. Relypsa is dedicated to the discovery of additional product candidates through use of its proprietary polymer platform. Privately-held, Relypsa's investors include: OrbiMed Advisors, 5AM Ventures, Delphi Ventures, New Leaf Venture Partners, Sprout Group, Amgen and Mediphase Venture Partners. For additional information, please see the Relypsa website at www.relypsa.com.