The goals of this study are to evaluate the efficacy of JNJ-18038683 in an 8 week trial to ameliorate the cognitive deficit and reduce residual depressive symptoms in 60 stable bipolar outpatients receiving treatment for depression. JNJ-18038683 will be studied and compared with placebo as adjunctive treatment to standard pharmacologic treatment for bipolar disorder.

Most, but not all, patients with bipolar disorder (BPD) have clinically significant cognitive impairment. Impairment is present in both the manic and depressed phases of BPD, as well as in euthymic periods. The percentage of BPD patients with cognitive impairment (CIBD) varies among studies, with 40-60% representing the best estimate. The weight of the evidence supports no overall difference in the type and severity of cognitive impairment in any phase of BPD, i.e. it is a stable trait feature of BPD, albeit variable from one patient to another. The most commonly affected cognitive domains are speed of processing, declarative memory, attention and working memory. Although CIBD is milder in severity than the cognitive impairment associated with schizophrenia (CIAS), on average, as in schizophrenia, CIBD has a major impact on function and quality of life in most patients, particularly because the greater preservation of function of BPD enables them to engage in activities which are more dependent on intact cognitive function. Thus, it is highly likely that improvement in CIBD will have valuable clinical benefit, especially with regard to quality of life measures. It is reasonable to predict that treatments effective to improve CIBD could also be beneficial for CIAS. Efficacy for cognitive impairment is likely to be greater in BPD than schizophrenia, because the baseline severity is milder in the former. Despite this strong rationale for targeting CIBD, there has been minimal focus on clinical trials to improve CIBD, perhaps because so many resources have been devoted to the effort to treat CIAS, but lack of appreciation of the severity of CIBD and its importance as a determinant of functional outcome in BPD may be the most important factors.

In a recent study of CIBD, using the MATRICS Consensus Cognitive Battery (MCCB), impairment was found in both treatment resistant BP I and II depressed inpatients within all MCCB domains. The greatest impairment was evident in speed of processing, declarative memory and attention. The impairment was numerically greater in BP I than BP II patients but the difference was not significant. Compared to normal controls, the deficits, in BP 1 patients, in speed of processing was 1.2SD, in attention, 1.0 SD, and in verbal learning, 1.8 SD. The least affected domain was visual learning, with a mean deficit of 0.8SD compared to normal controls. The mean composite score deficit was 1.25 SD. Medication for BPD, particularly mood stabilizers, may adversely affect some domains of cognition in BPD. However, antidepressant medications have not been found to affect the severity of cognitive impairment in major depression or BPD.

Based on the pre-clinical, pro-cognitive effects of 5-HT7 antagonism in our laboratory, along with the reported pre-clinical antidepressant effects of JNJ-18038683, we propose to conduct a randomized, placebo- controlled parallel, design study to assess the effects of JNJ-18038683 on multiple domains of cognition and mood symptoms. Since our preclinical studies show that 5-HT7 receptor blockade is highly effective in improving declarative memory in rodents, the declarative memory measures will be the primary outcome measures.

Due to the effect of JNJ-18038683 on depressive symptoms in preclinical paradigms, we will investigate the following in the clinical trial the potential antidepressant effect of JNJ-18038683 on patients with baseline MADRS score between 8 and 20.

Inclusion Criteria

1. All participants must have signed an informed consent document indicating they understand the purpose of the study and the procedures required for the study and are willing to participate by complying with the study procedures and restrictions.

2. Male or female individuals of any race; between 18 to 60 years of age, inclusive.

3. Resides in a stable living situation, according to the investigator's judgment.

4. Diagnosis of bipolar disorder I or II for at least 1 year in duration, as established by the SCID-I, and verified with medical records and/or confirmation of diagnosis by treating clinician. Patients will be in a nonacute phase at the time of initial screening and have been so for at least 1 month.

5. No more than moderate clinical symptom burden severity, as defined by the following: Montgomery Asberg Depression Rating Scale < 20 Young Mania Rating Scale <12

6. Individuals medically stable enough to complete an 8 week clinical trial, in the judgment of the investigator

7. Women of childbearing potential must have a negative pregnancy serum test at screening, negative pregnancy urine test at baseline, and agree to use adequate protection (i.e. double barrier method) for birth control.

8. Antidepressant (AD) medications are allowed if the subject has been treated with a stable dose for at least 2 months before screening.

9. Individuals receiving a single mood stabilizer (e.g., lithium. valproate, or lamictal) are allowed if a stable dose has been maintained for at least 2 months prior to screening.

10. Individuals may be receiving one treatment of each the following groups:

    antidepressants, mood stabilizers, and atypical antipsychotics other than clozapine, but not more than one from each group.

11. Individuals taking ripseridone, lurasidone, or ziprasidone must be currently taking < doses of 3mg, 40mg, and, 80mg, respectively.

12. Subjects may be treated with inclusionary antipsychotic drugs as long as they are on a stable dose of injectable medication for 2 months or a sable dose of an oral medication for 1 month. Exclusionary antipsychotic drugs are listed in Appendix 2 in the protocol.

13. Patients with a history of compliance with a drug treatment regimen for bipolar disorder, as noted in medical/psychiatric history.

14. CNS stimulants (e.g., Adderall, Ritalin) are permitted if the participant is stable on their dosage of medication for 1 month before screening and cannot change dosage throughout the study.

15. Able to complete cognition assessments in English

16. Individuals must demonstrate a substantive cognitive deficit, as measured by the Trails A, Hopkins Verbal Learning Test (HVLT), and the Letter Number Span, administered at the screening visit. Eligible individuals will have an established cognitive deficit as measured by one or more of these tests, scoring below the 75th percentile, using comparative norms according to age, gender, and education.

17. Able to understand and complete cognition assessments

Exclusion Criteria

1. Failure to perform screening or baseline examinations
2. Hospitalization within 8 weeks before screening, or change in mood stabilizing or antidepressant medication or dose within 2 months prior to screening.
3. Individuals who have participated in another clinical study within the past 2 months.
4. Individuals with tardive dyskinesia.
5. Individuals with other DSM-V Axis I or Axis II primary diagnoses.
6. Diagnosis of alcohol or substance use disorder within the past 3 months.
7. Subject assessed to be at significant suicide risk based on responses to the Columbia Suicide Severity Rating Scale (C-SSRS).
8. History of myocardial infarction, unstable angina, uncontrolled hypotension or hypertension within 3 months before screening.
9. Clinically significant abnormality on screening ECG.
10. Alanine transaminase (ALT) or aspartate transaminase (AST) > 2.5 times the upper limit of normal (ULN).
11. History of stroke, brain tumor, head trauma with loss of consciousness, or other clinically significant neurological condition within 12 months before screening.
12. Individuals with other uncontrolled medical conditions, in the opinion of the investigator.
13. Use of drugs known to be metabolized by CYP2D6.

During the study, from baseline to week12 (from baseline to 4 weeks after the study completion)

The total number affected by any Serious Adverse Event was 4 patients but 5 events.

Regarding Non-Serious Adverse Events, reports are according to the threshold of 5%