Relypsa : Announces Publication of Results of Veltassa Drug-Drug Interaction Studies in Journal of Cardiovascular Pharmacology and Therapeutics

NEWS RELEASE

Contact: Albert Liao

Director of U.S. Communications Relypsa

[phone]

[e-mail]

Relypsa Announces Publication of Results of Veltassa Drug-Drug Interaction Studies in

Journal of Cardiovascular Pharmacology and Therapeutics

• Phase 1 studies with 12 oral medications commonly used in hyperkalemic patients with chronic kidney disease showed minimal risk for drug-drug interactions with Veltassa when other oral drugs are administered 3 hours apart

• Veltassa label was recently updated based on Phase 1 results, with removal of Boxed Warning regarding drug-drug-interactions

REDWOOD CITY, Calif., February 13, 2017 - Relypsa, Inc., a Vifor Pharma company, today announced that results of drug-drug interaction studies of Veltassa® (patiromer) for oral suspension were published online by the Journal of Cardiovascular Pharmacology and Therapeutics. Results from 12 individual Phase 1 studies in healthy volunteers of 12 oral medications showed there were no clinically meaningful or statistically significant interactions between Veltassa and the 12 oral medications when taken at least three hours apart. Relypsa previously announced these findings in January 2016.

"These Phase 1 studies in healthy volunteers were rigorously designed to maximize the probability of identifying drug-drug interactions with Veltassa if they were to occur," said Lawrence J. Lesko, Ph.D., lead author of the publication, and Professor and Director of the Center for Pharmacometrics and Systems Pharmacology at the University of Florida College of Pharmacy in Orlando, Fla. "We believe these clinical results confirm minimal risk of drug-drug interactions with Veltassa and the majority of the drugs tested. Furthermore, where an interaction was observed, separating Veltassa from the other oral medications by at least 3 hours removed the potential for an interaction. These findings significantly add to our understanding of Veltassa and how to avoid drug-drug interactions with co-administered oral medications."

Based on these study results, the U.S. Food and Drug Administration (FDA) recently approved a supplemental New Drug Application (sNDA) for Veltassa with important updates to the label. Veltassa's updated label no longer includes a Boxed Warning that Veltassa binds to many orally administered medications and now recommends that patients take Veltassa at least 3 hours before or 3 hours after other oral medications. Veltassa was approved by the FDA for the treatment of hyperkalemia in the United States in October 2015, becoming the first medicine in more than 50 years for people with elevated blood potassium levels.

"With the change to a 3-hour dose separation between Veltassa and other medications, physicians now have increased flexibility in selecting Veltassa for patients with hyperkalemia and adding it to their daily treatment regimen," said Lance Berman, M.D., chief medical officer of Relypsa. "We are pleased by

these study results and by the updated Veltassa label and are working to provide this information to physicians who treat patients with hyperkalemia."

Results of Veltassa Drug-Drug Interaction Studies

Previously, Relypsa tested 28 drugs likely to be used in chronic kidney disease (CKD) patients with hyperkalemia to determine the potential for interaction with Veltassa. Drug-drug interaction tests conducted in vitro (in test tubes) showed that 14 drugs did not bind with Veltassa. Of the 14 drugs that did show an interaction, 12 were selected for further testing in Phase 1 studies. They are amlodipine, cinacalcet, ciprofloxacin, clopidogrel, furosemide, levothyroxine, lithium, metformin, metoprolol, trimethoprim, verapamil and warfarin. Two drugs were not tested: thiamine, as it is readily available in food, and quinidine, which is not commonly used.

Dr. Lesko and colleagues studied the 12 drugs in 12 separate randomized, open-label Phase 1 studies in a total of 370 healthy volunteers. The studies had a three-way crossover design in which each study participant received the test drug alone, Veltassa and the test drug administered at the same time, and Veltassa administered 3 hours after the test drug. Each study evaluated the concentration of the test drug in the blood over time and peak blood concentration of the test drug.

Results showed that Veltassa did not alter the extent of systemic absorption of nine of the 12 drugs when co-administered. Veltassa reduced absorption of three drugs when co-administered. However, there was no clinically significant interaction when Veltassa and these three drugs were taken 3 hours apart. Across all 12 studies, Veltassa was generally well tolerated with safety findings consistent with U.S. prescribing information.

The publication is available in the Online First section of the Journal of Cardiovascular Pharmacology and Therapeutics' website at http://journals.sagepub.com/doi/full/10.1177/1074248417691135.

About Hyperkalemia

Approximately 3 million people in the United States with stage 3 or 4 chronic kidney disease (CKD) and/or heart failure have hyperkalemia, or elevated blood potassium levels. Hyperkalemia can cause abnormal heart rhythms and even sudden death. There are often no warning signs, meaning a person can unknowingly experience spikes in potassium levels recurrently and be at risk for these cardiac events.

Some medicines that are often prescribed to people with CKD and heart failure to help delay progression of their underlying disease can cause hyperkalemia as a side effect. These include renin angiotensin aldosterone system (RAAS) inhibitors such as angiotensin receptor blockers (ARBs), aldosterone antagonists (AAs) and angiotensin-converting-enzyme (ACE) inhibitors.

About Veltassa

Veltassa is a potassium binder approved for the treatment of hyperkalemia. Veltassa should not be used as an emergency treatment for life-threatening hyperkalemia because of its delayed onset of action.

Made in powder form consisting of smooth, spherical beads, Veltassa is mixed with water (one-third of a cup) and taken once-a-day with food. Veltassa is not absorbed and acts within the gastrointestinal tract. It binds to potassium in exchange for calcium, primarily in the colon. The potassium is then excreted from the body through the normal excretion process.

Important Safety Information Contraindications

Veltassa is contraindicated in patients with a history of a hypersensitivity reaction to Veltassa or any of its components.

Worsening of Gastrointestinal Motility

Use of Veltassa should be avoided in patients with severe constipation, bowel obstruction or impaction, including abnormal post-operative bowel motility disorders, because Veltassa may be ineffective and may worsen gastrointestinal conditions. Patients with a history of bowel obstruction or major gastrointestinal surgery, severe gastrointestinal disorders, or swallowing disorders were not included in clinical studies.

Hypomagnesemia

Veltassa binds to magnesium in the colon, which can lead to hypomagnesemia. In clinical studies, hypomagnesemia was reported as an adverse reaction in 5.3 percent of patients treated with Veltassa. Approximately 9 percent of patients in clinical trials developed hypomagnesemia with a serum magnesium value

Adverse Reactions

The most common adverse reactions (incidence ≥2 percent) are constipation, hypomagnesemia, diarrhea, nausea, abdominal discomfort and flatulence. Mild to moderate hypersensitivity reactions were reported in 0.3 percent of patients treated with Veltassa and included edema of the lips.

For Veltassa's full Prescribing Information, please visit https://www.veltassa.com/pi.pdf.

About Relypsa, Inc.

Relypsa, Inc. is a biopharmaceutical company focused on the discovery, development and commercialization of polymeric medicines for patients with conditions that are often overlooked and undertreated and can be addressed in the gastrointestinal tract. The Company's first medicine, Veltassa® (patiromer) for oral suspension, was developed based on Relypsa's rich legacy in polymer science.

Relypsa was founded in 2007 and, in September 2016, became a Vifor Pharma company. More information is available at www.relypsa.com.

About Vifor Pharma

Vifor Pharma, a company of the Galenica Group, is a world leader in the discovery, development, manufacturing and marketing of pharmaceutical products for the treatment of iron deficiency. The company also offers a diversified portfolio of prescription medicines as well as over-the-counter (OTC) products. Vifor Pharma, headquartered in Zurich, Switzerland, has an increasingly global presence and a broad network of affiliates and partners around the world. For more information about Vifor Pharma, please visit www.viforpharma.com.

###