B-MS' Nefazodone: Launch Soon In USA

Bristol-Myers Squibb has received approval in the USA for its novel antidepressant drug Serzone (nefazodone). This is the second approval for the drug; it was originally approved in Canada earlier on in 1994.

Nefazodone acts as an antagonist at 5-HT2 receptors and also prevents 5-HT reuptake, as well as inhibiting noradrenaline uptake by presynaptic noradrenaline autoreceptors. The company believes that nefazodone therefore represents a new and useful approach to the management of depression, targeting both serotonergic and noradrenergic transmission, which is also seen with other new agents such as Wyeth-Ayerst's Effexor (venlafaxine) and Organon's recently-introduced Remeron (mirtazepine).

In effect, the rationale behind the design of new antidepressants has gone full circle; the older tricyclic agents targeted both serotonergic and noradrenergic systems but were associated with certain side effects. Companies therefore developed agents which are more selective to serotonin, ie the selective serotonin reuptake inhibitors (eg Lilly's fluoxetine, Pfizer's sertraline, SmithKline Beecham's paroxetine and Solvay's fluvoxamine). Now, facilitating both noradrenergic and serotonergic transmission while providing selective antagonism at certain 5-HT subtypes associated with side effects should, theoretically at least, result in effective agents with "cleaner" profiles.