A Double-Blind, Randomized, Placebo-Controlled, Multicenter, Fixed Dose Study to Assess Efficacy, Safety, and Tolerability of TC-5619 as Augmentation Therapy to Improve Cognition in Outpatients With Cognitive Dysfunction in Schizophrenia
Overview
- Phase
- Phase 2
- Intervention
- TC-5619
- Conditions
- Cognitive Dysfunction
- Sponsor
- Targacept Inc.
- Enrollment
- 184
- Locations
- 16
- Primary Endpoint
- To assess the efficacy of TC-5619 as augmentation therapy to quetiapine or risperidone, to improve cognition in stable outpatients with Cognitive Dysfunction in Schizophrenia (CDS), using the GML test of the CogState Schizophrenia Test Battery (CSTB).
- Status
- Completed
- Last Updated
- 12 years ago
Overview
Brief Summary
Schizophrenia affects approximately 1% of the population worldwide, and in about 80% of cases, it is a lifelong, disabling illness. It is a multi-dimensional disease that is associated with symptoms that have been characterized as positive, negative, and cognitive. CDS is a core feature of schizophrenia, and most individuals with schizophrenia exhibit cognitive impairment. Attention disorders, slow information processing, working memory disorders, and lack of flexibility for adaptive strategies are symptoms of cognitive impairment that have a devastating impact on the function, employment, and social status of patients with schizophrenia.
Older typical neuroleptic medications (e.g., haloperidol, fluphenazine) do not improve cognition. In fact, haloperidol has been shown to induce cognitive impairment in schizophrenic patients.
Novel atypical antipsychotics, such as risperidone, clozapine, and olanzapine, seem to produce gains in cognition. This improvement may reflect a diminution of extrapyramidal side effects of the typical high potency neuroleptics. Alternatively, it might reflect more effective symptom reduction by the novel antipsychotics, or direct cognitive enhancement through the effects of the newer agents on a variety of neurotransmitters, their receptors, and gene expression. Even when the newer antipsychotic medications improve cognition, they do not normalize it.
Presently, there are no approved therapies for CDS. However, in schizophrenic patients, nicotine improves multiple cognitive domains, including working memory and attention. Furthermore, based on a strong body of evidence ranging from genetic mapping to clinical trials, the alpha7 NNR subtype has emerged as a primary therapeutic target relevant to CDS and other core symptoms of schizophrenia
Investigators
Eligibility Criteria
Inclusion Criteria
- •Diagnosis of schizophrenia, per DSM-IV TR criteria, as aided by the MINI International Neuropsychiatric Interview (MINI)
- •Controlled schizophrenia, on same dose of quetiapine or risperidone for no less than 2 months prior to screening
- •Age 18 - 60, male or female
- •Stable schizophrenia as documented by lack of psychiatric hospitalization for 2 months prior to Screening
- •Clinical history of stable psychotic symptoms for 1 month prior to Screening
- •Stable positive symptoms of schizophrenia for 4 weeks prior to Day 1, as shown by score ≤ 4 on PANSS for items related to delusion, hallucination, conceptual disorganization, and unusual thought content, at Screening and at Day 1
- •Calgary Depression Scale for Schizophrenia score \< 6
- •Outpatient with stable housing, and presence of an informant who sees the subject at least 4 times weekly
- •Able to understand and sign informed consent
Exclusion Criteria
- •Diagnosis of schizoaffective or schizophreniform disorders 1 year prior to Screening
- •Patients at significant risk of suicide or of danger to themselves or others
- •Antipsychotics other than quetiapine or risperidone, or a change in dosing of these within 2 months of Screening
- •Treatment with mood stabilizers, antidepressants, or anxiolytics (short-acting hypnotics permitted)
- •Treatment within 1 month using cognition-affecting agents other than the above, as listed in Appendix 3 (e.g. CNS stimulants)
- •Use of other prohibited concomitant medications
- •Other concomitant medications that have been changed within 1 month prior to Screening
- •History within past 6 months of alcohol or illicit drug abuse
- •Use of smoking cessation therapy within 1 month prior to Screening
- •Tobacco users with no detectable urine cotinine level; and tobacco non-users with a detectable urine cotinine level
Arms & Interventions
TC-5619
TC-5619 capsules will be administered once a day in a forced titration scheme at 1 mg for 4 weeks, 5 mg for 4 weeks and 25 mg for 4 weeks (12 weeks total).
Intervention: TC-5619
Placebo
Intervention: Placebo
Outcomes
Primary Outcomes
To assess the efficacy of TC-5619 as augmentation therapy to quetiapine or risperidone, to improve cognition in stable outpatients with Cognitive Dysfunction in Schizophrenia (CDS), using the GML test of the CogState Schizophrenia Test Battery (CSTB).
Time Frame: Day 1 - Week 4; Week 4 - Week 8; and finally Week 8 - Week 12. There will be a 2-week follow-up period following the end of the treatment period.
Secondary Outcomes
- Assess the efficacy, safety and tolerability of TC-5619 administered adjunctively with quetiapine or risperidone, evaluate the pharmacokinetics of TC-5619 and plasma levels of quetiapine and risperidone/9-OH-risperidone.(Day 1 - Week 4; Week 4 - Week 8; and finally Week 8 - Week 12. There will be a 2-week follow-up period following the end of the treatment period.)