UK-based biotechnology firm e-Therapeutics has initiated a randomised, double-blind controlled Phase IIb study of ETS6103 as a second-line treatment for patients who have not responded adequately to first-line therapy with selective serotonin reuptake inhibitor (SSRI).
The trial is being conducted by a group of primary care centres with a history of involvement in depression studies in Glasgow, Scotland.
Under the trial protocol, about 160 patients will be enrolled prior to first-line treatment and will be given the SSRI citalopram.
The company said patients with significant depressive symptoms remaining after six weeks on citalopram will enter the randomised phase of the trial, which compares two different doses of ETS6103 with amitriptyline, a tricyclic antidepressant.
The main aim of the trial is to test whether the two ETS6103 regimens have antidepressant activity non-inferior to that of amitriptyline.
Primary measure of activity is the change in Montgomery-Åsberg Depression Rating Scale (MADRS) score between randomisation and the end of treatment eight weeks later, while safety and several secondary efficacy variables will also be evaluated in the trial.
Results of the trial will be released in the first half of 2015 and if these are positive the company expects to seek a licensing deal for the drug.
e-Therapeutics development director Stephen Self said a clear need exists for better treatments for patients who do not respond well to first-line anti-depressant therapies.
"We believe that ETS6103 has potential in this population and are working with an experienced group of clinicians to test this proposition in a randomised controlled trial," Self said.
The company said that an earlier small Phase IIa trial released encouraging results when it compared ETS6103 with the established antidepressant amitriptyline in patients with major depressive disorder.