A Phase 1, Open-label, Randomized, Three-period Crossover Drug Interaction Study Evaluating the Pharmacokinetic Profiles of SPD503 and CONCERTA, Administered Alone and in Combination in Healthy Adult Volunteers

This is a drug-drug interaction study; the purpose of this study is to examine the pharmacokinetics (levels of drug in the blood) of SPD503 (guanfacine hydrochloride) and Concerta (methylphenidate HCl) when given alone, and in combination.