Purity >98%. Monoamine oxidases, MAO-A and MAO-B, regulate the intracellular concentrations of biogenic monoamines such as 5-hydroxytryptamine and dopamine via oxidative deamination. Inhibitors of MAO-A are widely used for the therapy of affective disorders, whereas MAO-B inhibitors have clinical efficacy in the treatment of Parkinson's disease. Lazabemide is a reversible inhibitor of monoamine oxidase B (MAO-B) with IC50 values of 0.48 and 1.5 μM measured in platelets of human subjects ages 19-36 and 60-78, respectively. It is structurally similar to the MAO-B preferential substrate phenylethylamine and can be oxidized by MAO-B, forming tightly, but reversibly, bound adducts with the active site of the enzyme. The selectivity of lazabemide for MAO-B inhibition has been demonstrated in both in vitro and ex vivo conditions and it was evaluated in clinical trials for possible neuroprotective actions in the treatment of Parkinson's disease.