Safety and Efficacy of Add-On Oral Bexarotene to Antipsychotic Treatment in Schizophrenia Patients: An Open Label Trial

In this proposed study, we aim to investigate the effects of Bexarotene (Targretin; LGD1069; 4-[1-{5,6,7,8-tetrahydro-3,5,5,8,8-pentamethyl-2-naphthalenyl} ethenyl] benzoic acid) on severity of psychopathology, cognitive impairment, and quality of life in schizophrenia patients in an open label trial. The rationale behind add-on oral bexarotene to ongoing antipsychotic treatment in schizophrenia patients is based on both the retinoid dysregulation hypothesis (Goodman, 1995) and the growth factors deficiency and synaptic destabilization hypothesis (Moises et al, 2002) of schizophrenia. In this clinical trial, a novel regimen of low dose bexarotene (Targretin, 75 mg/day) will be added for 6 weeks to the standard treatment of 15 schizophrenia patients on stable antipsychotic treatment. Participants will be assessed at baseline and after 2, 4 and 6 weeks of treatment. A battery of research instruments will be used for assessment of efficacy and safety (psychopathology, and side effects). In addition, cholesterol and triglyceride levels, liver and thyroid function tests and a blood cell count will be monitored at baseline and during therapy.