In Part I, 12 subjects were randomly allocated to one of 2 cohorts, running in parallel. The 6 cohort 1 subjects received 25 mg and then 200 mg during their treatment periods 1 and 2, respectively. The 6 cohort 2 subjects received 75mg, 500mg, and 1000 mg during their treatment periods 1, 2, and 3, respectively. During Part II of the study, the same 12 subjects from Part I were randomized to receive either 200 mg jet or placebo in a 1:1 ratio.