BACKGROUNDThis first-in-human study evaluated HRS-1780, an oral selective non-steroidal mineralocorticoid receptor antagonist, in healthy men.RESEARCH DESIGN AND METHODSIn single ascending dose (SAD) part, 10 participants for each dose cohort (5, 10, 20, 40, 60, and 80 mg) were randomized (8:2) to HRS-1780 or placebo. In multiple ascending dose part, 12 participants for each dose (10, 20, and 40 mg) were randomized (9:3) to HRS-1780 or placebo once daily for 7 days. The primary endpoint was safety and tolerability.RESULTSHRS-1780 was well tolerated with all adverse events being mild. In the steady state, the median time to maximum concentration (Tmax) was 0.750 h and mean half-life was 1.76-1.96 h. High-fat/high-calorie meal prolonged Tmax but did not affect exposure. Multiple dosing of HRS-1780 at 40 mg showed a decreasing trend in systolic blood pressure compared with placebo. Changes in plasma aldosterone and norepinephrine with HRS-1780 were higher compared to placebo. Upper bounds of two-sided 90% confidence interval of placebo-adjusted change-from-baseline QTcF were below 10 msec at the maximum concentration in SAD. The trial had limited sample size and short study duration.CONCLUSIONSHRS-1780 had favorable safety and pharmacokinetic profiles and did not cause clinically meaningful QTcF prolongation.TRIAL REGISTRATIONClinicalTrials.gov (NCT05638126).