A Study to Evaluate the Safety and Efficacy of BIIB104 in Participants With Cognitive Impairment Associated With Schizophrenia (CIAS)

A Phase 2, Randomized, Double-Blind, Multiple-Dose, Placebo-Controlled Study to Evaluate the Safety and Efficacy of BIIB104 in Subjects With Cognitive Impairment Associated With Schizophrenia (CIAS)

The primary objective of the study is to evaluate the efficacy of BIIB104 in participants with CIAS, using the Working Memory Domain of the MATRICS Consensus Cognitive Battery (MCCB).

The secondary objectives of this study are to evaluate the safety and tolerability of BIIB104 in participants with CIAS, and to evaluate the efficacy of BIIB104 in participants with CIAS on measures of cognition, functioning, and psychiatric symptomology.

Key Inclusion Criteria:

• Otherwise healthy participant with a Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), diagnosis of schizophrenia of at least 2 years' duration as confirmed by the mini-international neuropsychiatric interview (MINI) 7.0.2 for Psychotic Disorders.
• Evidence of stable schizophrenia symptomatology ≥12 weeks (e.g., no hospitalizations for schizophrenia, no increase in level of psychiatric care due to worsening of schizophrenia symptoms).
• Participants must be in ongoing maintenance atypical antipsychotic therapy (except clozapine), on a stable treatment regimen for ≥8 weeks prior to Baseline/Day 1, including concomitant psychotropic medication. Doses of background atypical antipsychotics should be within the recommended dose range listed in the approved product labeling of the country where the study is being conducted.
• SCI-PANSS: No more than moderate-severe rating (score ≤5) on delusions, hallucinatory behavior, grandiosity, suspiciousness / persecution, and hostility (i.e. PANSS, positive symptom items P1, P3, P5, P6, P7); or unusual thought content (G9); and no more than a moderate rating (score ≤4) on conceptual disorganization (P2).

Key Exclusion Criteria:

• Participation in a trial using any component or version of the MATRICS Consensus Cognitive Battery (MCCB) or the University of California, San Diego (UCSD) Performance-Based Skills Assessment test within the previous 6 months.
• Participation in cognitive remediation therapy within 6 months prior to randomization.
• Screening MCCB Working Memory Domain T-score ≥60.
• Current DSM-5 diagnosis of schizoaffective disorder on the MINI 7.0.2 for Psychotic Disorders.
• Current DSM-5 diagnosis of major depressive episode, manic and hypomanic episode, panic disorder, agoraphobia, social anxiety disorder, obsessive-compulsive disorder, posttraumatic stress disorder, and/or generalized anxiety disorder on the MINI 7.0.2 for Psychotic Disorders.
• Lifetime DSM-5 diagnosis of antisocial personality disorder, anorexia nervosa, bulimia nervosa, and/or binge-eating disorder on the MINI 7.0.2 for Psychotic Disorders.
• Meets the DSM-5 diagnosis of moderate or severe substance use disorder (excluding nicotine dependence) within 12 months of screening on the MINI 7.0.2 for Psychotic Disorders interview.
• DSM-5 diagnosis of Intellectual Disability (intellectual developmental disorder).

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.