Add-on fluvoxamine treatment for schizophrenia: An updated meta-analysis of randomized controlled trials

We performed an updated meta-analysis of fluvoxamine add-on therapy in patients with schizophrenia treated with antipsychotics based on two previous meta-analyses (Sepehry et al., in J Clin Psychiatry 68:604-610, 2007 and Singh et al., in Br J Psychiatry J Mental Sci 197:174-179, 2010). We searched PubMed, the Cochrane Library database, and PsycINFO up to January 2013. We conducted a systematic review and meta-analysis of individual patient data from randomized controlled trials comparing fluvoxamine add-on therapy with placebo. The risk ratio (RR), 95 % confidence intervals (CI), and standardized mean difference (SMD) were calculated. Seven studies (total n = 272) were identified. These included two clozapine studies, one olanzapine study, one second-generation antipsychotic (SGA) monotherapy study, and three first-generation antipsychotics (FGAs) monotherapy studies. There were significant effect of fluvoxamine add-on therapy on overall (SMD = -0.46, CI = -0.75 to -0.16, p = 0.003, I ² = 0 %, 5 studies, n = 180) and negative symptoms (SMD = -0.44, CI = -0.74 to -0.14, p = 0.004, I ² = 0 %, 5 studies, n = 180). However, fluvoxamine add-on therapy showed no significant effects on positive symptoms, depressive symptoms, and discontinuations from any cause or adverse events. Fluvoxamine add-on therapy in patients primarily treated with SGAs improved overall (p = 0.02) but not negative symptoms (p = 0.31). On the other hand, fluvoxamine add-on therapy in patients primarily treated with FGAs improved both overall (p = 0.04) and negative symptoms (p = 0.004) compared with control groups. Our results suggest that fluvoxamine add-on therapy is more beneficial on the psychopathology (especially negative symptoms) than controls in patients with schizophrenia who are primarily treated with FGAs. Given that a small number of studies were included in this meta-analysis, the results should be treated with caution.