A Study to Evaluate the Efficacy and Safety of GDC-8264 in Preventing Cardiac Surgery-Associated Acute Kidney Injury (AKI) and Major Adverse Kidney Events (MAKE)

Open to people ages 40 years and up

1. One of the following non-emergent cardiac surgery types that requires cardiopulmonary bypass (CPB) to be done in one procedure rather than separate procedures: Isolated Coronary Artery Bypass Grafting (CABG); Isolated Surgical Aortic Valve Replacement (AVR), Mitral Valve Replacement (MVR), Mitral Valve repair (MVr); Combined CABG+AVR, CABG+MVR, CABG+MVr, AVR+MVR, AVR+MVr
2. At least one or at least two of the following AKI risk factors, depending on the type of surgery: age > 70 years, history of CKD with eGFR < 60 milliliters/ minutes/ 1.73 meter square (ml/min/1.73 m²) within the last 6 months, diabetes (type 1 or type 2) requiring at least one oral hypoglycemic agent or insulin, history of chronic obstructive pulmonary disease (COPD) requiring medical therapy, left ventricular ejection fraction (LVEF) < 40%, preoperative anemia [hemoglobin <10 grams/deciliters (g/dL)]
3. Stable kidney function with no known episodes of AKI within 2 weeks of screening

1. Need for renal replacement therapy (peritoneal dialysis or hemodialysis)
2. Need for intra-aortic balloon pump, temporary mechanical circulatory support, or extracorporeal membrane oxygenation prior to scheduled surgery
3. Presence of a durable left ventricular assist device
4. Need for concurrent aortic surgery that requires circulatory arrest and deep hypothermia or repair of congenital heart defects
5. Heart transplant
6. Transcatheter valve replacements
7. Hypotension or shock requiring hospital admission
8. Cardiopulmonary resuscitation
9. eGFR < 20 mL/min/1.73 m²
10. Heart failure with ejection fraction < 20%, or episode of decompensated heart failure requiring intervention within 2 weeks prior to screening
11. History of kidney transplant or only one kidney (due to donation)
12. Renal agenesis, total nephrectomy, or partial nephrectomy of > 50%