Efficacy and Safety Study of Adjunctive Troriluzole in Obsessive Compulsive Disorder

Inclusion Criteria:

1. Primary diagnosis of obsessive-compulsive disorder (OCD) as per Diagnostic andStatistical Manual of Mental Disorders, Fifth Edition as confirmed by the MINI atScreening; The duration of the subject's illness must be ≥ 1 year

2. An inadequate response to current Standard of Care medication defined as selectiveserotonin reuptake inhibitor (excluding fluvoxamine) or clomipramine treatment at anadequate and stable dose for at least 8 weeks prior to screening and at least 12weeks at baseline (adequate dose defined by USPI labeling); an inadequate responseas defined per the MGH-TRQ-OCD, there has been minimal or no meaningful clinicalbenefit as perceived by the subject

3. Determined by the investigator to be medically stable at baseline/randomization asassessed by medical history, physical examination, laboratory test results, andelectrocardiogram testing. Subjects must be physically able and expected to completethe trial as designed

Exclusion Criteria:

1. Subjects with a history of more than two (2) previous failed or inadequate treatmentclasses given for an adequate duration at an adequate dose as defined by theMGH-TRQ-OCD.

2. Current or prior history of: bipolar I or II disorder, schizophrenia or otherpsychotic disorders, schizoaffective disorder, autism or autistic spectrumdisorders, borderline personality disorder, antisocial personality disorder,Tourette's disorder, body dysmorphic disorder, hoarding disorder; or psychosurgery,Deep Brain Stimulation (DBS) or Electroconvulsive Therapy (ECT); or general medicalcondition that may confound safety and/or efficacy results

3. Previous treatment in a study with troriluzole