Remission with mirtazapine and selective serotonin reuptake inhibitors: a meta-analysis of individual patient data from 15 controlled trials of acute phase treatment of major depression.

Antidepressants that enhance both serotonergic and noradrenergic neurotransmission may be more effective than selective serotonin reuptake inhibitors (SSRIs) for acute-phase therapy of major depressive disorder. Mirtazapine in particular has been suggested to have a faster onset of action than reuptake inhibitors. The aim of this study is to compare the remission rates and time to remission in patients with major depression taking either mirtazapine or an SSRI in an all-inclusive set of studies. Data were obtained from all eligible randomized controlled studies contrasting mirtazapine and SSRIs. Meta-analyses of remission rates and time to remission, together with a supportive analysis of mean change from baseline Hamilton Depression Rating Scales-17 were performed, using individual patient data from 15 randomized controlled trials of mirtazapine (N = 1484) versus various SSRIs (N = 1487) across 6 weeks of double-blind therapy. Analyses were repeated for the eight studies that lasted at least 8 weeks. Remission rates for patients treated with mirtazapine were significantly higher when compared with those treated with an SSRI after 1 (3.4 vs. 1.6%, P = 0.0017), 2 (13.0 vs. 7.8%, P<0.0001), 4 (33.1 vs. 25.1%, P<0.0001), and 6 weeks (43.4 vs. 37.5%, P = 0.0006) of treatment. Mirtazapine-treated patients had a 74% higher likelihood of achieving remission during the first 2 weeks of therapy compared with patients treated with SSRIs. In conclusion, the findings indicate that mirtazapine may be a more rapidly effective antidepressant than SSRIs.

Mirtazapine orally disintegrating tablets versus venlafaxine extended release: a double-blind, randomized multicenter trial comparing the onset of antidepressant response in patients with major depressive disorder.

This randomized, multicenter, double-blind study was designed to compare specifically the onset of antidepressant action of mirtazapine orally disintegrating tablets (ODT) with venlafaxine extended-release (XR) formulation in outpatients with major depression. Both treatments were administered in a rapidly escalating dosing regimen. Target doses (mirtazapine ODT, 45 mg OD; venlafaxine XR, 225 mg OD) were reached by day 6 of treatment. On the primary efficacy parameter [the average of the change in HAM-D (17-item) total score on days 5, 8, 11, and 15], mirtazapine ODT was significantly superior to venlafaxine XR (P = 0.008). In addition, calculating the HAM-D score without the sleep items resulted in significant reductions in favor of mirtazapine ODT on days 8 (P = 0.006) and 11 (P = 0.037). The proportion of responders (HAM-D decrease of > or =50% from baseline) was higher in the mirtazapine ODT group on all assessment days, being significant on days 8 (P = 0.002), 11 (P = 0.004), and 22 (P = 0.027). More patients in the mirtazapine ODT group achieved remission (HAM-D total score of < or =7) up to day 29, and the difference was statistically significant on day 15 (P = 0.016). Significant differences in favor of mirtazapine ODT were evident in the CGI of change on days 8 (P = 0.019), 11 (P = 0.004), and 15 (P = 0.031), and the CGI of severity on days 8 (P = 0.014) and 11 (P = 0.033). Both treatments were well tolerated. These results indicate that mirtazapine ODT has a faster onset of antidepressant efficacy than venlafaxine XR in patients with major depressive disorder, and that this effect is independent of its sleep-improving properties.