Many modern antidepressant drugs are available that work by improving the neurotransmission of serotonin, norepinephrine, or both.
A third neurotransmitter, dopamine, is also implicated in mood enhancement and the pathophysiology of depression, and US biotech Euthymics Bioscience is working on amitifadine, a drug that acts as a reuptake inhibitor of all three of these hormones as a potential treatment for patients with major depressive disorder.1
A six week, randomised, double blind, parallel, placebo controlled trial has been carried out in 63 patients with major depressive disorder.2 They were randomised to receive either 25mg of amitifadine twice a day for two weeks, followed by 50mg twice a day for a further four weeks, or placebo.
After the six-week period, the mean change from baseline in the Montgomery-Åsberg depression rating scale was statistically significantly better for those who had received the drug compared with the placebo group. The drug was well tolerated, and while two patients on each treatment arm discontinued the trial early because of adverse events, none reported serious adverse events. Further trials are now underway.
references
1. P. Skolnick et al. Eur. J. Pharmacol. 2003, 461, 99
2. P. Tran et al. J. Psychiatr. Res. 2012, 46, 64
