Early Clinical Experience With AZD4831, A Novel Myeloperoxidase Inhibitor, Developed for Patients With Heart Failure With Preserved Ejection Fraction.

We evaluated safety, tolerability, pharmacokinetics (PKs), and pharmacodynamics of AZD4831, a novel oral myeloperoxidase (MPO) inhibitor, in a randomized, single-blind, placebo-controlled study, following once-daily multiple ascending dosing to steady-state in healthy subjects. Target engagement was measured as specific MPO activity in plasma following ex vivo zymosan stimulation of whole blood. Except for generalized maculopapular rash in 4 of 13 subjects receiving the 2 highest doses, 15 and 45 mg AZD4831, no clinically relevant safety and tolerability findings were observed. AZD4831 was rapidly absorbed and plasma concentrations declined slowly with an elimination half-life of ~ 60 hours. A dose/concentration-effect relationship between MPO inhibition vs. AZD4831 exposure was established with > 50% MPO inhibition in plasma at concentrations in the low nanomolar range. Steady-state levels were achieved within 10 days. Taken together, the PK profile, the sustained dose/concentration-dependent MPO inhibition, and available clinical data support further clinical development of AZD4831 in patients with heart failure with preserved ejection fraction.