A Study to Evaluate the Safety and Efficacy of AC607 for the Treatment of Kidney Injury in Cardiac Surgery Subjects

Inclusion Criteria: * Age ≥ 21 years * Had cardiovascular surgery utilizing cardiopulmonary bypass * Have a pre-operative (baseline) serum creatinine value collected within 30 days of surgery (if multiple laboratory results are available within this time window, the most recent serum creatinine value prior to surgery will be used to establish the baseline) * Willing and able to comply with visit schedule and study procedures including post-hospitalization discharge follow-up * Ability to give informed consent or have a legally acceptable representative do so for them * Have AKI defined as ≥ 0.5 mg/dL rise in serum creatinine from baseline within 48 hours of removal from cardiopulmonary bypass Exclusion Criteria: * Active cancer and/or receiving active treatment for cancer, with the exception of squamous cell or basal cell carcinoma of the skin * Had surgery for thoraco-abdominal aortic aneurysm (TAAA) * Currently participating in another interventional drug or device clinical study * Prisoner or other detainee * Has a current medical condition that would preclude or compromise femoral artery catheter placement * Has an intra-aortic balloon pump (IABP) in place within 2 hours of catheter placement * Has a ventricular assist device (VAD) or extracorporeal membrane oxygenation (ECMO) in place at the time of the study catheter placement * Prior history of solid organ or bone marrow transplant * Stage 5 CKD or currently on dialysis * Are expected to receive dialysis within 24 hours of enrollment or dosing * Had a complication during surgery or post-operatively that, in the opinion of the principal investigator (PI), significantly increases the risk of complications to the subject and therefore precludes dosing the subject * Are pregnant or lactating. A woman with child-bearing potential may be tested for pregnancy at the discretion of the PI.