Either pregnenolone (30 mg/d or 200 mg/d), DHEA (400 mg/d)or placebo will be added to regular treatment for 8 weeks. Subjects will be assessed at baseline and after 2, 4, 6 and 8 weeks of treatment. An extensive battery of research instruments will be used for assessment of the following domains of interest: psychopathology, insight, side effects, and cognitive functions. Plasma pregnenolone, DHEA(S), cortisol and other relevant steroids will be assayed at baseline, 2, 4, 6 and 8 weeks of treatment. Efficacy and safety of augmentation of antipsychotic treatment with pregnenolone will be analyzed.