Biochemical pharmacology of befloxatone (MD370503), a new potent reversible MAO-A inhibitor.

In vitro and ex-vivo studies show that befloxatone, a new oxazolidinone derivative, is a potent, reversible, competitive and specific MAO-A inhibitor (KiA from 1.9 to 3.6 nM and KiB/KiA ratio between 100 and 400, in the Rat and in Man, depending on the tissue). Befloxatone possesses a marked activity in antidepressant-sensitive behavioral models in rats (from 0.03 to 0.15 mg/kg po) and mice (from 0.21 to 0.29 mg/kg po). At these doses, befloxatone does not induce a significant potentiation of oral tyramine. Befloxatone is devoid of sedative, anticholinergic and cardiovascular effects. Befloxatone is rapidly and extensively distributed in rat brain, the pharmacokinetics are linear in the rat and in man in a large range of doses. Befloxatone is well tolerated in healthy volunteers and is developed as an antidepressant.