Safety and Efficacy of Fingolimod in Schizophrenia Patients Who Have Suboptimal Responses to Antipsychotic Drug Treatment

Study Design:

This will be a single site safety and proof of concept study conducted at the Indiana University Psychotic Disorders Program. Forty subjects with schizophrenia or schizoaffective disorders will be randomized 1:1 to double-blind treatment with fingolimod or matched placebo for duration of 8 weeks.

All subjects will be admitted to the Indiana Clinical and Translational Sciences Institute Clinical Research Center (CRC) and remain hospitalized for the first 24 (+/- 2) hours post initial dose of study medication. The CRC is located in Indiana University Hospital and has 24 hour staffing with nurses skilled in conducting Phase 1 and Phase 2 investigational drug studies.

Background and Rationale:

Schizophrenia is a severe brain disorder that begins during the teenage years and early twenties and typically progresses to a life-long chronic illness marked by psychotic symptoms, cognitive impairment and poor functioning. A leading hypothesis to account for the symptoms and cognitive dysfunction of this disorder is that abnormalities exist in cortical circuits, particularly in frontal and temporal areas. An interest in cortical circuitry has led to a focus on the integrity of cortical white matter tracts as possibly contributing to the pathophysiology of this illness. Indeed, several lines of evidence have supported abnormalities in white matter structure and function in schizophrenia. Numerous myelin-related genes and their functional expression have been associated with schizophrenia. Moreover, quantitative and qualitative abnormalities in prefrontal cortical oligodendrocytes have been found in postmortem studies. MRI-determined volumetric reductions in prefrontal white matter have been reported in schizophrenia. Advances in MRI technology have enhanced the ability to study white matter pathology in vivo. Diffusion tensor imaging (DTI) and fractional anisotropy (FA) provides an assessment of the density and integrity of white matter tracts. Decreased FA has been reported in many de-myelinating diseases including multiple sclerosis (MS), leukodystrophies, and HIV. Numerous studies using DTI have reported decrements in FA in schizophrenia with the most consistent abnormalities occurring in frontal cortical white matter. Also, FA has been shown to be sensitive to therapeutic drug effects in MS which supports DTI-derived FA as an outcome measure in clinical trials of neuroprotective agents.