This is a randomized, double-blind, placebo-controlled, multiple-dose phase Ib study.~It aimed in this study to evaluate the safety and tolerability and to characterize the pharmacokinetics of ZM-H1505R among Chinese healthy subjects following single and multiple doses administration, and to assess whether there are ethnic differences in PK characteristic among Chinese and American healthy subjects. Study was also conducted to evaluate the safety and tolerability, to characterize the pharmacokinetics and to assess the preliminary pharmacodynamics of ZM-H1505R following multiple ascending dose administration among chronic hepatitis B virus-infected patients; the PK/PD model was established among adults to provide a basis for the oral doses determination in subsequent clinical studies of ZM-H1505R.~Part I: Study among healthy subjects for safety evaluation and PK bridging Based on the PK results among American healthy subjects in Phase Ia study, 75 mg (cohort 1) was selected for PK bridging. Twelve healthy subjects were enrolled, of which 8 subjects received ZM-H1505R and 4 subjects received placebo.~Part II: Study among chronic hepatitis B virus-infected patients Subjects in four cohorts (scheduled as cohort 2, 50 mg; cohort 3, 100 mg; cohort 4, 200 mg; cohort 5, 300 mg) were enrolled in sequence from 50 mg dose group (cohort 2). Dose ascending was continued when safety evaluation on Day 8 showed that the lower dose could be tolerated. Based on the results of PK and tolerability and PD, dose ascending to 300 mg dose group (cohort 5) from 200 mg dose group (cohort 4) was discontinued determined by sponsor and investigators. Ten chronic hepatitis B virus-infected patients were enrolled in each cohort to receive ZM-H1505R (n=8) or placebo (n=2).
This phase Ib study included two parts in which Part I was to evaluate the safety and bridge for PK among healthy Chinese subjects and Part II were about study among Chinese chronic hepatitis B virus-infected patients. Study of Part II was carried out following the safety assessment and racial difference evaluation in Part I.