BACKGROUND: We investigated the effects of sacubitril/valsartan, a first-in-class angiotensin receptor neprilysin inhibitor (ARNI), on 24-hour blood pressure (BP) and safety for 12 weeks in Japanese patients with non-dialysis advanced chronic kidney disease (CKD). METHODS: We conducted a prospective, single-arm exploratory study. Patients with non-dialysis CKD stage G4-5 (estimated glomerular filtration (eGFR) <
30 mL/min/1.73 m2) who did not achieve their BP goals with angiotensin receptor blocker (ARB) administration, were enrolled and switched to sacubitril/valsartan. Primary and key secondary endpoints were changes from baseline in the 24-hour systolic BP (SBP) measured via ambulatory BP monitoring (ABPM) over 12 weeks and the safety, especially incidence of serum creatinine (Cr) increase (≥30% increase from baseline) and hyperkalemia. RESULTS: Thirty patients were enrolled, and 29 patients were switched to sacubitril/valsartan. Efficacy analysis was conducted on 26 patients. Baseline mean eGFR and office BP were 21.1±5.0 mL/min/1.73m2 and 149.4±23.7/80.7±11.9 mmHg, respectively. Baseline 24-hour, daytime, and nighttime BP were 139.6±17.7/77.0±7.8 mmHg, 143.5±18.5/79.6±8.7 mmHg, and 131.0±20.4/71.1±8.8 mmHg, respectively. After 12 weeks, changes in 24-hour, daytime, and nighttime SBP from baseline were -7.1±12.4 mmHg (P <
0.01), -7.7±12.9 mmHg (P <
0.01), and -5.8±15.8 mmHg (P = 0.07), respectively. No incidences of potassium values >
6.0 mmol/L or serum Cr ≥30% increase from baseline were reported after sacubitril/valsartan initiation. CONCLUSIONS: Switching from ARB to sacubitril/valsartan can safely enhance 24-hour antihypertensive treatment in patients with non-dialysis CKD G4-5 who do not achieve BP goals with ARBs.CLINICAL TRIALS REGISTRATION: Trial Number jRCT1031220149.