Clinical outcome and tolerability of duloxetine in the treatment of major depressive disorder: a 12-week study with plasma levels

• Published in: Journal of psychopharmacology (Oxford) 2010-08, Vol.24 (8), p.1193-1199
• Main Authors: Volonteri, LS, Colasanti, A., Cerveri, G., Fiorentini, A., De Gaspari, IF, Mauri, MC, Valli, A., Papa, P., Mencacci, C.
• Format: Article
• Language: English
• Subjects: Adrenergic Uptake Inhibitors - adverse effects; Adrenergic Uptake Inhibitors - blood; Adrenergic Uptake Inhibitors - therapeutic use; Adult and adolescent clinical studies; Aged; Anxiety; Biological and medical sciences; Clinical outcomes; Correlation analysis; Depression; Depressive Disorder, Major - drug therapy; Duloxetine Hydrochloride; Female; Humans; Male; Medical sciences; Medical treatment; Mental depression; Middle Aged; Mood disorders; Neuropharmacology; Pharmacology. Drug treatments; Plasma; Psychiatric Status Rating Scales; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer..., (alzheimer disease); Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Psychopharmacology; Serotonin Uptake Inhibitors - adverse effects; Serotonin Uptake Inhibitors - blood; Serotonin Uptake Inhibitors - therapeutic use; Thiophenes - adverse effects; Thiophenes - blood; Thiophenes - therapeutic use; Time Factors; Treatment Outcome
• ISSN: 0269-8811; 1461-7285
• DOI: 10.1177/0269881109104863

Duloxetine (DLX) is a dual serotonin and norepinephrine reuptake inhibitor that has been recently approved for the treatment of major depressive disorder (MDD). However, little is known about the relationship between DLX plasma levels and clinical response. The aims of this open-label study were 1) to assess clinical outcome and tolerability of DLX by means of clinician and patient assessments and 2) to evaluate the value of plasma DLX levels as predictors of clinical response and tolerability. This was a naturalistic, open-label study of 45 outpatients affected with MDD (16 men and 29 women), who received DLX at doses of 30—120 mg/day and were evaluated at baseline (T0) and after 2, 4 and 12 weeks (T1—3). The assessments included the Hamilton Rating Scales for Depression (HRSD) and Anxiety (HRSA), Clinical Global Impression-Severity (CGI-S), Beck’s Depression Inventory (BDI) and a mood visual analogue scale (VAS). Compared with T0, there were significant improvements in HRSD at T1, T2 and T3 (P < 0.001), in HRSA, CGI-S and the self-administered BDI at T2 and T3 (P < 0.001), and in the VAS scores shown at T3 (P = 0.01). DLX treatment was safe and well tolerated. Plasma DLX levels at T2 ranged from 5 to 135 ng/mL (mean ± SD = 53.56 ± 39.45) and correlated almost significantly with the DLX dose (r = 0.35; P = 0.069). There was a significant curvilinear quadratic relationship between the improvement of HRSA scores and plasma DLX levels (R2 = 0.27; P = 0.02). The incidence of anxiety or irritability was associated with the highest plasma levels. Our findings suggest that monitoring plasma DLX levels may be helpful in predicting better treatment responses and tolerability. The present data seem to suggest an optimal anxiolytic efficacy of DLX at intermediate plasma levels.