In all 4 studies, duloxetine demonstrated superiority over placebo as measured by improvement in the 17-item Hamilton Depression Rating Scale (HAMD-17) total score (Studies 1 to 4 in Table 7).
In all of these clinical studies, analyses of the relationship between treatment outcome and age, gender, and race did not suggest any differential responsiveness on the basis of these patient characteristics.

Table 7: Summary of the Primary Efficacy Results for Studies in Major Depressive Disorder

SD: standard deviation; SE: standard error; LS Mean: least-squares mean; CI: confidence interval, not adjusted for multiplicity in trials where multiple dose groups were included.

aDifference (drug minus placebo) in least-squares mean change from baseline.

b Doses statistically significantly superior to placebo.

Primary Efficacy Measure: HAMD-17
 
Study
Number
 Treatment Group
 Mean Baseline Score (SD)
 LS Mean Change from Baseline (SE)
 Placebo-subtracted Differencea
(95% Cl)
 
Study 1
 Duloxetine (60 mg/day) b
 21.5 (4.10)

 -10.9 (0.70)

 -4.9 (-6.8, -2.9)

 Placebo
 21.1 (3.71)
 -6.1 (0.69)
 --
 
Study 2
 Duloxetine (60 mg/day) b 
 20.3 (3.32)

 -10.5 (0.71)

 -2.2 (-4.0, -0.3)

 Placebo
 20.5 (3.42)
 -8.3 (0.67)
 -
 
Study 3
 Duloxetine (20 mg BID) b
 18.6 (5.85)

 -7.4 (0.80)

 -2.4 (-4.7, -0.2)

 Duloxetine (40 mg BID) b
 18.1 (4.52)

 -8.6 (0.81)

 -3.6 (-5.9, -1.4)

 Placebo
 17.2 (5.11)
 -5.0 (0.81)
 --
 
Study 4
 Duloxetine (40 mg BID) b
 19.9 (3.54)

 -11.0 (0.49)

 -2.2 (-3.6, -0.9)

 Duloxetine (60 mg BID) b
 20.2 (3.41)

 -12.1 (0.49)

 -3.3 (-4.7, -1.9)

 Placebo
 19.9 (3.58)
 -8.8 (0.50)
 --
In another study, 533 patients meeting DSM-IV criteria for MDD received duloxetine 60 mg once daily during an initial 12-week open-label treatment phase. Two hundred and seventy-eight patients who responded to open label treatment (defined as meeting the following criteria at weeks 10 and 12: a HAMD-17 total score ≤9, Clinical Global Impressions of Severity (CGI-S) ≤2, and not meeting the DSM-IV criteria for MDD) were randomly assigned to continuation of duloxetine at the same dose (N=136) or to placebo (N=142) for 6 months. Patients on duloxetine experienced a statistically significantly longer time to relapse of depression than did patients on placebo (Study 5 in Figure 1). Relapse was defined as an increase in the CGI–S score of ≥2 points compared with that obtained at week 12, as well as meeting theDSM-IV criteria for MDD at 2 consecutive visits at least 2 weeks apart, where the 2-week temporal criterion had to be satisfied at only the second visit. The effectiveness of duloxetine in hospitalized patients with major depressive disorder has not been studied.

Figure 1

14.2 Generalized Anxie