R1 Therapeutics adds $3M to reach $80.5M Series A for kidney drug
What's the deal? R1 Therapeutics has expanded its Series A financing to $80.5 million, adding new investor Samsara BioCapitalDealroom has a profile for this one. Try Dealroom → to fund a global Phase 2b trial of its lead kidney drug. The Redwood City biopharmaceutical company builds on an oversubscribed $77.5 million round announced in March 2026.
Who else is in? Samsara joins a syndicate that includes AbingworthDealroom has a profile for this one. Try Dealroom →, DaVita Venture GroupDealroom has a profile for this one. Try Dealroom →, F-Prime, Curie.BioDealroom has a profile for this one. Try Dealroom →, SNMA Capital, and U.S. Renal CareDealroom has a profile for this one. Try Dealroom →.
What's the endgame? Proceeds will advance AP306, a first-in-class pan phosphate transporter inhibitor being tested as a monotherapy for hyperphosphatemia in dialysis patients with chronic kidney disease. It is the only agent that blocks the "active" transport of phosphate, targeting three transporters in the gut. Topline Phase 2b data are expected in the first half of 2027.
Why now? The investment lands ahead of that readout. "Their decision to join ahead of the Phase 2b readout is a strong endorsement of our novel approach," said Krishna Polu, co-founder, president and chief executive officer.
Why it matters: Phosphate binders have been the standard of care for 60 years, yet more than 70% of US dialysis patients fail to reach normal phosphate levels. Uncontrolled hyperphosphatemia contributes to cardiovascular disease, bone disease, and mortality.
What could go wrong? The company's value rests on a single clinical-stage asset that has yet to report Phase 2b results. R1 has licensed global rights outside Greater China to AP306 from Alebund Pharmaceuticals, which is running the trial's China sites.
The signal: Backing from a syndicate heavy with kidney-care specialists — DaVita and U.S. Renal Care among them — points to appetite for a mechanism that could displace a decades-old treatment approach, if the data holds.
Read more: benzinga.com
Image credit: newslighter
