R1 Therapeutics is a clinical-stage biopharmaceutical company focused on developing first-in-class therapies for patients with kidney disease. Its lead program, AP306, targets hyperphosphatemia in patients with chronic kidney disease on dialysis and is described as a pan phosphate active transport inhibitor that blocks three key phosphate transporters in the gut. R1 positions AP306 as designed to deliver rapid and effective phosphate lowering with a reduced treatment burden. The company is partnering with Alebund on AP306 and plans to start a Phase 2b study later this year. R1 is led by Co-Founder, President and CEO Krishna Polu and is based in Redwood City, CA. The company strengthened its balance sheet with a $77.5M Series A to support its global development program.

Total raised

$78M

Funding rounds

1

Latest round

Series A

Latest activity

Mar 2026