Clinical pharmacology studies of befloxatone, a new selective reversible inhibitor of monoamine oxidase-A (MAO-A), have addressed safety, with special emphasis on tyramine interactions, and have also investigated pharmacokinetics (PK) and pharmacodynamics in terms of both MAO-A inhibition (using 3,4-dihydroxyphenylglycol, DHPG, as a pharmacological activity marker) and effects on psychomotor and cognitive function, in young and elderly healthy volunteers. Clinical and laboratory safety data were satisfactory in healthy volunteers given single doses of up to 160 mg or repeated doses of up to 80 mg/day for 7 days. Tyramine interaction studies showed that the expected potentiation of the tyramine pressor effect occurred with a safety margin that was so wide as to make dietary restrictions unnecessary with dosages of up to 20 mg once daily in clinical settings. Absorption was rapid (tmax = 2 h), terminal halflife was about 11 h, and PK parameters increased linearly with the dose. Befloxatone induced a dose-dependent decrease in plasma DHPG levels from 2.5 mg upwards, and a 10-mg dose provided sub-maximal activity (80% DHPG decrease) of 24 h duration. No sedative or stimulant effects were detected using several batteries of psychometric tests. Befloxatone was devoid of deleterious effects on memory in young volunteers, and exhibited the EEG profile of a non-sedative antidepressant. In summary, available clinical pharmacology studies confirm that befloxatone is a safe and potent RIMA with no potential for inducing deleterious CNS effects.