Reducing Involuntary Movements in Participants With Tardive Dyskinesia
Condition: Tardive Dyskinesia
MeSH terms: Dyskinesias; Tardive Dyskinesia
Intervention: SD-809; Placebo
Intervention description: SD-809 will be administered per dose and schedule specified in the arm.; Placebo matching to SD-809 will be administered per schedule specified in the arm.
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 343.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No
Keywords: Dyskinesias; Movement Disorders; Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Signs and Symptoms

Summary:

      The purpose of this study is to evaluate the long-term safety, tolerability, and efficacy of
      SD-809 in reducing the severity of abnormal involuntary movements of moderate to severe
      tardive dyskinesia. The purpose of part B is to establish the durability of effect of SD-809
      following 1-week period of randomized withdrawal (SD-809 and placebo), followed by 12 weeks
      of maintenance with SD-809.
    

Eligibility criteria:

        Inclusion Criteria:

          -  History of using a dopamine receptor antagonist for at least 3 months

          -  Clinical diagnosis of tardive dyskinesia and has had symptoms for at least 3 months
             prior to screening

          -  Participant has successfully completed a controlled study of SD-809 for treatment of
             moderate to severe tardive dyskinesia

          -  Participants with underlying psychiatric diagnosis are stable and have no change in
             psychoactive medications

          -  Have a mental health provider and does not anticipate any changes to treatment regimen
             in the next 3 months

          -  History of being compliant with prescribed medications

          -  Able to swallow study drug whole

          -  Be in good general health and is expected to attend all study visits and complete
             study assessments

          -  Female participants must not be pregnant and agree to an acceptable method of
             contraception

        Exclusion Criteria:

          -  Currently receiving medication for the treatment of tardive dyskinesia

          -  Have a neurological condition other than tardive dyskinesia that may interfere with
             assessing the severity of dyskinesias

          -  Have a serious untreated or undertreated psychiatric illness

          -  Have recent history or presence of violent behavior

          -  Have unstable or serious medical illness

          -  Have evidence of hepatic impairment

          -  Have evidence of renal impairment

          -  Have known allergy to any component of SD-809 or tetrabenazine

          -  Has participated in an investigational drug or device trial (other than Study C-18,
             Study C-23, or any other eligible TEV-50717 parent study) and received study drug
             within 30 days

          -  Have acknowledged use of illicit drugs

          -  Have a history of alcohol or substance abuse in the previous 12 months