Efficacy, Safety, and Tolerability of TC-5619 in Adults With Attention Deficit/Hyperactivity Disorder (ADHD)

A randomized, parallel, forced-titration design is being used to assess effects of TC-5619 versus placebo on efficacy. A parallel group design allows the effects of TC-5619 to be clearly established, and the randomized nature of the design allows minimization of observer and subject bias. Because a forced dose up-titration design will be used, effects of individual doses will be preliminary, because the design confounds dose with time. The doses chosen (1mg, 5mg, and 25mg) reflect an appropriate range around the anticipated efficacious dose (3-10 mg), based upon preclinical extrapolations to the human, and upon the pro-cognitive effects of TC-5619 identified by CDR in the MRD study (Targacept Study TC-5619-238-CLP-002). All subjects will be tobacco non-users. It is possible that tobacco (nicotine) interferes with α7 NNR-mediated effects.