In addition, subjects were to receive exogenous test administrations(stimulation test) on Day -1, Day 1 and Day 7 at the same time on each day (ie for Day -1, 23.5 h before the first dose of IMP, and for Days 1 and 7, 0.5 h after the first dose of IMP on the respective day). Blood samples for PD and PK analyses were taken at specified time points after each dosing.