Early Improvement With Vilazodone Might Predict Response, Remission in GAD

Sufficient dosing and treatment duration might be needed to assess vilazodone's effectivness for management of symptoms among patients with GAD, concluded authors of a pooled analysis of data from three phase 3 clinical trials.

SAN ANTONIO, TX—Vilazodone, a selective serotonin reuptake inhibitor (SSRI) and 5-HT1A receptor partial agonist approved for treating adults with major depressive disorder, might help some patients with generalized anxiety disorder (GAD) better manage symptoms, according to findings from an analysis of data pooled from three randomized, double-blind, placebo-controlled trials, presented at the U.S. Psychiatric & Mental Health Congress.

“At Week 8, the percentage of patients with HAMA [Hamilton Anxiety Rating Scale] response or remission was significantly greater with vilazodone than placebo,” reported lead study author Anita Clayton, MD, of the University of Virginia, in Charlottesville, VA, and coauthors.

At Week 4, among patients with available HAMA assessments, vilazodone was associated with a significantly better rate of Week 8 response (49.5% vs. 39.6%; P<0.001) and Week 8 remission (28.9% vs. 21.7%; OR: 1.5; 95% CI: 1.1–1.9; P<0.01), the authors reported.

HAMA remission rates at Week 8 were 26.0% for patients receiving vilazodone and 20.0% for patients receiving placebo (odds ratio [OR]: 1.4; 95% CI: 1.1–1.8).

Week 4 early improvement might be a better predictor of response and remission, but early improvement “did not perfectly predict Week 8 outcomes,” they cautioned. Results from the predictive model were similar for placebo and vilazodone-treated patients, and Week 4 improvement was noted for half (50.7%) of HAMA-assessed placebo-treated patients, compared to 62.6% of vilazodone-treated patients, they noted. 

SSRIs and serotonin norepinephrine reuptake inhibitors (SNRIs) are first-line pharmacotherapies for GAD, but many patients do not adequately respond to these medications, the authors reported.

To assess vilazodone management of GAD, authors pooled data from 3 randomized, double-blind, placebo-controlled clinical trials (NCT01629966, NCT01766401, and NCT01844115) of vilazodone (20–40 mg daily) in adult patients diagnosed with GAD. The pooled intention-to-treat (ITT) population included 844 patients administered vilazodone and 618 patients in clinical trial placebo groups.

“In patients with GAD, sufficient dosing and treatment duration may be required before any conclusions can be made regarding an individual patient’s responsiveness to vilazodone,” the authors concluded.