Efficacy and Safety of NBI-98854 in Subjects With Tardive Dyskinesia

This is a Phase 2, open-label, dose titration study to assess the efficacy and safety of three once daily (q.d.) doses (12.5, 25, and 50 mg) of NBI-98854 administered once daily for up to 12 days consisting of three treatment periods of 4 days each (Periods 1, 2, and 3). The starting dose will be 12.5 mg q.d. (Period 1), and this dose will be escalated to 25 mg q.d. (Period 2) and then to 50 mg q.d. (Period 3) based upon each subject's ability to tolerate NBI-98854. Progression to the next dose level will be based upon the subject's ability to tolerate the previous dose and the Investigator's review of adverse events and safety data. For subjects who do not tolerate a dose increase, the dose may be decreased to the dose that was previously administered (i.e., 25 mg to 12.5 mg, 50 mg to 25 mg) and continued at that dose for the remainder of the study treatment. Up to 10 medically stable subjects with schizophrenia or schizoaffective disorder who have moderate or severe symptoms of TD will be enrolled as outpatients.