The US Food and Drug Administration (FDA) has issued a clearance letter allowing Angion Biomedica to start its Phase II GUARD clinical trial (GUard Against Renal Damage) using investigational drug BB3 to treat patients at risk for acute kidney injury (AKI).

The company has been developing BB3, which is a proprietary small molecule that mimics the activity of hepatocyte growth factor (HGF). In preclinical models of AKI, BB3 showed organ protective and regenerative therapeutic effects.

Currently, there is no FDA approved drug therapy for the prevention or treatment of AKI, which is one of the most serious and frequent in-hospital complications.

Patients who undergo cardiac surgery involving use of cardiopulmonary bypass, also called as a heart-lung machine, in combination with predisposing factors, are at increased risk for AKI.

Angion president and CEO Itzhak Goldberg said: "The GUARD study complements our Phase III study on BB3 in renal transplant patients presenting with delayed graft function, another form of AKI."

The multicenter, randomized, placebo-controlled, double-blind GUARD study is designed to evaluate the potential of BB3 to treat AKI in patients who undergo open heart surgery and require the use of cardiopulmonary bypass.

Around 100 patients in the US who have risk factors for AKI including existing kidney disease, previous cardiac surgery, compromised heart function, advanced age and diabetes will be included in this trial.

University of Maryland School of Medicine professor of Medicine and Division of Nephrology head Matthew Weir said: "The evaluation of BB3 to treat patients at risk for AKI, and Angion's additional Phase 3 clinical trial of BB3 to treat delayed graft function in renal transplant patients, are both very exciting.

"Should BB3 prove effective for preventing or treating AKI, it will represent a major breakthrough in the field of nephrology."