This study is a pre-registration trial of generic duloxetine that was approved by the China Food
and Drug Administration (approval number: 2006L01603).
Compare the treatment efficacy and safety of generic duloxetine to that of paroxetine in patients with
major depressive disorders (MDD).
This was a double-dummy, double-blind, multicenter, positive drug (paroxetine), parallel
randomized controlled clinical trial. The 299 patients with MDD recruited for the study were randomly
assigned to use duloxetine (n=149; 40–60 mg/d) or paroxetine (n=150; 20 mg/d) for 8 weeks. The Hamilton
Depression rating scale (HAMD-17) was administered at baseline and 1, 2, 4, 6, and 8 weeks after starting
treatment. Remission was defined as a HAMD-17 score below 8 at the end of the trial, and treatment
effectiveness was defined as a decrease in baseline HAMD-17 score of at least 50% by the end of the trial.
Safety was assessed based on the reported prevalence and severity of side effects and changes in laboratory
and electrocardiographic findings. Three patients in the duloxetine group dropped out before starting
medication, so results were analyzed using a modified intention-to-treat (ITT) method with 146 in the
experimental group and 150 in the control group.
Both groups experienced 29 dropouts during the 8-week trial. HAMD-17 scores decreased
significantly from baseline throughout the trial in both groups. Based on the ITT analysis, at the end of
the trial there was no significant difference between the duloxetine group and the paroxetine group in
effectiveness (67.1% v. 71.3%, X2=0.62 p=0.433), remission rate (41.1% v. 51.3%, X2=3.12, p=0.077), or in
the incidence of side effects (56.8% v. 54.7%, X2=0.14, p=0.705).
Generic duloxetine is as effective and safe as paroxetine in the acute treatment of patients
with MDD who seek care at psychiatric outpatient departments in China.