Increased inflammation has been seen both in patients with chronic schizophrenia and first episode psychosis. Alongside hyperactivity of the hypothalamic–pituitary–adrenal (HPA) axis, increased inflammation has been implicated in the development of psychosis. However, it is still unclear if inflammation has a role in the course of the illness, in particular clinical outcomes. This study aimed to investigate the association between inflammatory biomarkers and treatment response in first episode psychosis. Inflammation was assessed using a clinically relevant measure of high-sensitivity C-reactive protein (hsCRP), at baseline and at three-month follow up. Treatment response was defined by remission of symptoms at three-month follow-up, using criteria established by the Remission in Schizophrenia Working Group (Positive And Negative Syndrome Scale). There were 14 non-responders (mean±SEM age: 26.8±2.1years) and 33 responders (age: 30.5±1.6years). Since previous research has shown an effect of gender and ethnicity on hsCRP levels, these were controlled for in the analysis. Non-responders showed significantly higher hsCRP levels than responders at baseline (3.9±1.6 vs. 1.3±0.4, p=0.04), however there was no significant difference in hsCRP levels between groups at three-month follow-up (3.1±1.3 vs. 2.6±1.0, p=0.7). Our results suggest that treatment response at three-month follow up is associated with increased inflammation at baseline. Baseline hsCRP may be used as predictor of clinical outcome.