Conditions: Tardive Dyskinesia
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 109
Healthy volunteers: no

Brief summary:
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.

Detailed description:
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.

Arms:
arm 1: NBI-98854 50 mg administered as two (2) 25 mg capsules by mouth, taken every morning between 7:00am - 10:00am for 6 weeks. arm 2: NBI-98854 100 mg administered as two (2) 50 mg capsules taken every morning between 7:00am - 10:00am for 2 weeks. After 2 weeks, NBI-98854 50 mg administered by two (2) 25 mg capsules by mouth, taken every morning between 7:00am - 10:00am for remaining 4 weeks. arm 3: Capsule containing no active substance, manufactured to mimic NBI-98854 25 mg and 50 mg capsules.

Interventions: intervention 1: NBI-98854 intervention 2: NBI-98854 intervention 3: Placebo
Intervention descriptions: intervention 1: 25 mg capsule intervention 2: 50 mg capsule intervention 3: None

Protocol document: