Pharmacokinetic and safety evaluation of MB12066, an NQO1 substrate.

OBJECTIVE: This study evaluated the pharmacokinetics (PKs) and safety of a newly developed β-lapachone (MB12066) tablet, a natural NAD(P)H:quinone oxidoreductase 1 (NQO1) substrate, in healthy male volunteers.

METHODS: In a randomized, double-blind, multiple-dose, two-treatment study, 100 mg MB12066 or placebo was given twice daily for 8 days to groups of eight or three fasted healthy male subjects, respectively, followed by serial blood sampling. Plasma concentrations for β-lapachone were determined using liquid chromatography-tandem mass spectrometry. PK parameters were obtained with non-compartmental analysis. Tolerability was assessed based on physical examinations, vital signs, clinical laboratory tests, and electrocardiograms.

RESULTS: Following a single 100 mg MB12066 oral dose, maximum plasma concentration ( C max ) of β-lapachone was 3.56±1.55 ng/mL, and the median (range) time to reach C max was 3 h (2-5 h). After the 8 days of 100 mg twice daily repeated dosing was completed, mean terminal half-life was determined to be 18.16±3.14 h, and the mean area under the plasma concentration vs time curve at steady state was 50.44±29.68 ng·h/mL. Accumulation index was 2.72±0.37. No serious adverse events (AEs) were reported, and all reported intensities of AEs were mild.

CONCLUSION: The results demonstrated that MB12066 was safe and well tolerated in healthy volunteers and that there were no serious AEs. Accumulation in plasma with twice-daily administration was associated with a 2.72 accumulation ratio.