The sample size is as large or greater than those in the previous human laboratory studies assessing safety and initial efficacy of agonist-like pharmacotherapies for stimulant dependence. For example, these previous studies used samples of 7 (Herin et al., 2010; Stoops et al., 2008; Dackis et al., 2003), and 10 (Sofuoglu et al., 2009) subjects to obtain significant reductions in subjective effects of d-amphetamine by atomoxetine and those of cocaine by modafinil.