Quetiapine addition to serotonin reuptake inhibitor treatment in patients with treatment-refractory obsessive-compulsive disorder: An open-label study

Objective: Although patients with obsessive-compulsive disorder (OCD) benefit from treatment with serotonin reuptake inhibitors (SRIs), it is estimated that 40% to 60% of the patients remain unimproved. The objective of this study was to examine whether addition of the atypical antipsychotic quetiapine to SRIs is useful for patients with OCD who do not respond to SRI monotherapy. Method. Ten patients with OCD (DSM-IV criteria) who had not responded to at least 3 previous treatments with an SRI at maximum dose and duration were assigned to receive quetiapine in addition to an SRI for 8 weeks. Treatment response was assessed using the Yale-Brown Obsessive-Compulsive Scale (YBOCS). Results: Seven of 10 patients responded to the quetiapine addition. The mean +/-SD baseline YBOCS score of 31.4 +/- 7.8 dropped to a mean of 20.8 +/- 8.4 at endpoint with a mean reduction of 35.4%. Conclusion: This is the first study to show that treatment-refractory OCD patients may benefit from addition of quetiapine to ongoing SRI therapy.