ZS Pharma Raises $55M to Develop Drug to Treat Hyperkalemia

ZS Pharma, a Fort Worth-area biotech developing a chronic kidney disease drug, has raised $55 million in new equity financing.

ZS Pharma will use the Series D funding round to continue to develop its lead drug candidate, ZS-9, an experimental treatment for people with hyperkalemia, and get the company to the point of filing new drug applications with the FDA and the European Medicines Agency. ZS Pharma expects to submit those documents to regulators in early 2015. New investors included Novo A/S, RA Capital, Adage Capital, Sofinnova Ventures. Existing investors such as Alta Partners, Devon Park Bioventures, 3×5 Special Opportunity Fund, Salem Partners, and RiverVest also participated in the financing.

At Kidney Week this past November, ZS Pharma reported that its drug reduced excess amounts of potassium in the blood of hyperkalemia patients. The finding—if confirmed in two additional studies planned for this year—could be medically significant. That’s because people with failing kidneys are often left with too much potassium in the blood, which can lead to potentially deadly irregular heart rhythms.

At that time, complete data from the phase III trial, which included 753 patients, had not been reported. Specifically, the company did not reveal patients’ baseline levels of potassium, so the preliminary results didn’t show if the drug was able to bring their potassium levels back to normal.

Author: Angela Shah

Angela Shah was formerly the editor of Xconomy Texas. She has written about startups along a wide entrepreneurial spectrum, from Silicon Valley transplants to Austin transforming a once-sleepy university town in the '90s tech boom to 20-something women defying cultural norms as they seek to build vital IT infrastructure in a war-torn Afghanistan. As a foreign correspondent based in Dubai, her work appeared in The New York Times, TIME, Newsweek/Daily Beast and Forbes Asia. Before moving overseas, Shah was a staff writer and columnist with The Dallas Morning News and the Austin American-Statesman. She has a Bachelor's of Journalism from the University of Texas at Austin, and she is a 2007 Knight-Wallace Fellow at the University of Michigan. With the launch of Xconomy Texas, she's returned to her hometown of Houston.