Effects of Oxytocin Nasal Spray on Social Affiliation

Effects of Oxytocin Nasal Spray on Social Affiliation

Schizophrenia is a complex and heritable disorder that encompasses several clinical symptom domains and functional impairments. Existing treatments of schizophrenia, although effective against positive symptoms, fail to benefit negative symptoms, the focus of the current protocol. One of the strategies of novel drug development depends on identifying heritable physiological deficits that mark the disease liability and are thought to occur along the causal pathway of negative symptoms. These heritable physiological deficits are often found in the biological relatives of schizophrenia proband; particularly those who have schizophrenia related personality styles [defined by schizophrenia spectrum personalities (SSP) in the diagnostic system], even though they do not have the full-blown illness. The current protocol will pilot a strategy of targeting biomarkers of negative symptoms using intranasal oxytocin in relatives of schizophrenia patients. The drug probe studies in such non-clinical sample have several advantages including the absence of other drug treatment that may modulate the response, and the lack of generalized deficits causing problems with task comprehension/engagement that may mute the therapeutic signal. In addition, finding of efficacy of the experimental drug on the target physiological deficit and the associated symptoms has clinical implications on its own rights. This is because about 25% of subjects with schizophrenia spectrum personality disorders experience serious functional impairments.

Oxytocin is an extensively used drug, which is well tolerated with few serious side effects. Several lines of evidence suggest its putative role in the treatment of negatives symptoms, particularly a lack of social drive and related symptoms.

The current study will examine the effects of intranasal oxytocin on physiological/cognitive markers of negative symptoms in 24 participants with schizophrenia spectrum traits. Subjects will be tested in two one-day studies carried out at least a month apart. Subjects will receive a 24 IU dose of intranasal oxytocin (or placebo) followed by a battery of cognitive/neurophysiological tests administered 50 minutes later completed over the next 155 minutes. A second dose of the drug (oxytocin or placebo) will be administered 2 hours after the 1st in order to maintain therapeutic plasma levels and to complete all testing.

Inclusion Criteria:

• Male/Female subjects between ages of 18-64 years
• The presence of 3 or more SSP symptoms (at least 2 of the SSP symptoms will be negative symptoms as defined by the schizoid traits)
• The presence of visuo-spatial working memory impairment as defined by error in the oculomotor delayed response (ODR) task of more than 0.5 SD above the mean values in healthy control subjects
• Relative of an individual with schizophrenia, schizo-affective, or schizophreniform disorder
• Able to provide written informed consent. Females are excluded due to risk of discomfort and unblinding due to potential uterine cramps induced by oxytocin.

Exclusion Criteria:

• Subjects meeting criteria for a life-time diagnosis of any one of the DSM IV, Axis I psychotic disorders (exceptions being a single past episode of major depressive disorder with psychotic features or psychotic symptoms associated with substance abuse with the substance abuse ending 6-months prior to study participation) (this is for the SSP recruitment)
• Subjects meeting DSM-IV criteria for current alcohol or substance dependence (other than nicotine) within the last 6 months or DSM-IV criteria for alcohol or substance abuse (other than nicotine) within the last month
• Medical conditions that preclude participation in drug trials or assessments of outcome measures (including significant brain, cardiac, liver, lung, endocrinological or metabolic disorders)
• Received any investigational drug in the preceding four weeks.