Lack of tyramine pressor response effect with oral CX157: A specific reversible MAOI

This Phase 1, single-center, double-blind, placebo-controlled, three-period study assessed cardiovascular safety of CX157, a specific Reversible Inhibitor of Monoamine Oxidase A (RIMA), following the oral administration of tyramine. In Period 1, the sensitivity of each subject to orally administered tyramine was established by determining the dose of tyramine that elevates SBP ≥30 mmHg on ≥3 consecutive occasions (i.e., TYR303 ). Twelve subjects qualified for randomization in Period 2 during which an oral CX157 Modified Release Tablet (125 mg [N = 10]) or placebo (N = 2) were administered twice per day for 6 days to reach steady state. In Period 3, CX157 and placebo were administered with oral tyramine in fed state with daily increases in the tyramine dose of 20, 40, and 80 mg in an attempt to achieve the TYR303 . CX157 Modified Release Tablet, 125 mg administered twice per day (250 mg daily dose), was not associated with a tyramine reaction (i.e., TYR303 ). It is generally agreed that a high tyramine meal would contain up to 40 mg of dietary tyramine. These data obtained with CX157 provide an adequate margin of safety with respect to tyramine interaction and suggest that future studies can be conducted without the need for dietary tyramine restrictions.