Renasant Bio, a new biotechnology company focused on developing treatments for autosomal dominant polycystic kidney disease (ADPKD), has raised $54.5 million in seed financing from prominent investors including 5AM Ventures, Atlas Venture, OrbiMed and Qiming Venture Partners USA. The company launched Thursday with a novel approach to treating the hereditary kidney condition that affects approximately 12 million people worldwide.
Novel Therapeutic Approach Inspired by Cystic Fibrosis
Renasant draws inspiration from successful drug development in cystic fibrosis, recognizing that both conditions are linked to malformed ion channels. Similar to how Vertex Pharmaceuticals' Trikafta works by correcting and boosting the activity of channel proteins in cystic fibrosis, Renasant believes it can develop "corrector" and "potentiator" treatments that restore and open up the channels relevant to ADPKD.
"What a corrector does is it helps that misfolded protein fold properly," explained Emily Conley, Renasant's CEO. "Once the protein gets into the right shape, then it can go where it needs to go, and then the potentiator holds the channel open."
Conley, a Stanford University scientist who previously led Federation Bio and oversaw business development at 23AndMe, emphasized the company's confidence in their approach: "We know what's broken. If we can fix it with correctors and potentiators, then we could have this very dramatic effect on patient outcomes."
Addressing a Significant Unmet Medical Need
ADPKD is one of the most prevalent hereditary kidney conditions, affecting approximately 300,000 Americans. The disease causes cysts to develop on patients' kidneys and sometimes their liver, with severe consequences for patients. "Ultimately, the cysts and their kidneys enlarge massively. Their kidneys can be 30 pounds a piece. You'll see people wearing T-shirts that say, 'I'm not pregnant. I have ADPKD,' because their kidneys balloons so much in size," Conley told STAT. The condition frequently pushes patients onto dialysis or leads to kidney failure.
Currently, treatment options remain limited. Patients can use Otsuka's Jynarque, which U.S. regulators cleared in 2018 to slow the decline in organ function caused by the condition, but they have few other good options. Sanofi was developing venglustat around the same time as Jynarque's approval but stopped clinical testing in 2021 after negative study results.
Development Pipeline and Leadership
Renasant's lead drug candidate is a small molecule corrector currently in preclinical testing. The company designed this molecule to work in patients with any of the wide range of mutations that cause ADPKD. While Renasant envisions this molecule working as a standalone treatment, it's also developing a potentiator that could be used in combination to prevent cysts from forming or growing in the kidney.
The company plans to enter clinical testing in the next few years. Overseeing Renasant's scientific work is Gus Gustafson, a veteran of large pharmaceutical firms including Johnson & Johnson and Merck & Co. The board of directors is led by Natalie Holles, former CEO of Third Harmonic Bio, and includes Charlotte McKee, chief medical officer of cystic fibrosis drugmaker Sionna Therapeutics, as well as venture investors.
Scientific Foundation and Competitive Landscape
Renasant originated from the research of University of California, San Francisco professors Jeremy Reiter and Markus Delling, who sent 5AM Ventures a cold email in 2022 with a pitch built from their research into the disease's biology. "Renasant has assembled the right team, with years of research experience in polycystic disease that has informed the right scientific approach," said Deborah Palestrant, a partner at 5AM, which incubated the biotech.
The company enters a competitive landscape where other major pharmaceutical companies are also pursuing ADPKD treatments. In April, Novartis agreed to pay $800 million to acquire Regulus Therapeutics and an experimental therapy, farabursen, that the Swiss pharmaceutical company said showed "promising clinical efficacy and safety." Vertex is also developing a drug for the disease, demonstrating continued industry interest in addressing this significant unmet medical need.
