This study was to evaluate the pharmacokinetics of single and multiple doses of oral lafutidine tablets and the effect of food on pharmacokinetics in healthy Chinese subjects. The tolerability and the effect of sex on the pharmacokinetic properties were also evaluated to acquire more pharmacokinetic information.

The study of single-dose was randomized, three-period, crossover. And in this study, 12 subjects were randomly assigned to 3 dose groups and received a single dose of 10mg, 20mg and 40mg lafutidine tablets. The washout period was 7 calendar days. In the multiple-dose, 12 subjects took lafutidine tablets of 10 mg twice a day for 6 consecutive days. In the food-effect study, 12 subjects were randomly assigned to 2 groups. One group received a single dose of 10mg lafutidine tablets under fasted condition, while the other were in fed condition. The drug administrations were separated by a wash-out period of seven calendar days. In each study group, the male and the female are both in half of the subjects. Using a liquid chromatography tandem mass spectrometry (LC/MS/MS) method to determine the plasma concentration of lafutidine. Pharmacokinetic parameters were calculated using the single compartment model.

Inclusion Criteria:

• body mass index between19 and 24 kg/m2
• negative for HIV and hepatitis B
• had no clinical important findings on health tests
• thorax radiography and ECG with no abnormalities
• normal blood pressure values
• heart rate

Exclusion Criteria:

• any drug treatment within 2 weeks before starting the study
• participation in another clinical study within the previous 3 months
• alcoholism and smoking
• pregnancy
• breast-feeding
• hypocalcemia
• blood donation or participation in other clinical trials within 3 months before enrollment in the study
• sitting blood pressure <80/50 mm Hg or >140/100 mm Hg
• A ventricular rate <60 beats/min or >100 beats/min at rest