NBI-98854 for the Treatment of Tardive Dyskinesia in Subjects With Schizophrenia or Schizoaffective Disorder (KINECT Study)

The purpose of this study is to evaluate the efficacy, safety, and tolerability of two doses (50 and 100 mg) of NBI-98854 administered once daily for the treatment of Tardive Dyskinesia (TD) symptoms.

This is a Phase 2, multicenter, randomized, double-blind, placebo-controlled, parallel group study to evaluate the efficacy, safety, and tolerability of two doses (50 and 100 mg) of NBI-98854 administered once daily for up to 2 weeks. The study will also allow for an evaluation of the efficacy of NBI-98854 50 mg once daily for up to 6 weeks and the safety and tolerability of NBI 98854 50 mg once daily for up to 12 weeks.

The double-blind placebo-controlled treatment period the study has three arms:

* NBI-98854 50 mg once daily for 6 weeks
* NBI-98854 100 mg once daily for 2 weeks followed by 50 mg once daily for the remaining 4 weeks
* placebo

At the end of the 6-week placebo-controlled double-blind treatment period, subjects will continue in the study for an additional 6-week open-label period where all subjects who have completed the double-blind treatment period will receive NBI-98854 50 mg once daily. Two and four weeks after the last dose of study drug, follow-up assessments will be performed.

Eligibility Criteria:
Inclusion Criteria:

* Have a clinical diagnosis of schizophrenia or schizoaffective disorder and a clinical diagnosis of neuroleptic-induced tardive dyskinesia for at least 3 months prior to screening.
* Be receiving a stable dose of antipsychotic medication for a minimum of 30 days before study start. Subjects who are not using antipsychotic medication must have stable psychiatric status.
* Have the doses of concurrent medications and the conditions being treated be stable for a minimum of 30 days before study start and be expected to remain stable during the study.
* Subjects of childbearing potential must agree to use hormonal or two forms of nonhormonal birth control during the study.
* Female subjects must not be pregnant.
* Be in good general health and expected to complete the clinical study as designed.
* Have a body mass index (BMI) of 18 to 38 kg/m2 (both inclusive).
* Have a negative urine drug screen (negative for amphetamines, barbiturates, benzodiazepine, phencyclidine, cocaine, opiates, or cannabinoids) at screening and study start, except for any subject receiving a stable dose of benzodiazepine.
* Have a negative alcohol breath test at screening and study start.

Exclusion Criteria:

* Have an active clinically significant unstable medical condition within 1 month (30 days) prior to screening.
* Have a history of substance dependence or substance (drug) or alcohol abuse within the 3 months before study start(nicotine and caffeine dependence are not exclusionary).
* Have a known history of neuroleptic malignant syndrome.
* Have a significant risk of suicidal or violent behavior.
* Receiving any excluded concomitant medication such as reserpine, metoclopramide, stimulants, or tetrabenazine.
* Receiving medication for the treatment of tardive dyskinesia.
* Have a positive human immunodeficiency virus antibody, (HIV-Ab), hepatitis B surface antigen (HBsAg), or hepatitis C virus (HCV) antibody result at screening or have a history of positive result.
* Have received an investigational drug within 30 days before screening or plan to use an investigational drug (other than NBI-98854) during the study.
* Have an allergy, hypersensitivity, or intolerance to tetrabenazine.
* Have had previous exposure with NBI-98854.