Thorough QT Study to Evaluate the Effect of Zoliflodacin, a Novel Therapeutic for Gonorrhea, on Cardiac Repolarization in Healthy Adults
Zoliflodacin is a novel spiropyrimidinetrione antibiotic being developed as single oral dose treatment to address the growing global threat of Neisseria gonorrhoeae . To evaluate the cardiac safety of zoliflodacin, a thorough QT/QTc (TQT) study was performed in healthy subjects. In this randomized, double-blind, placebo-controlled, 4-period crossover study, 72 subjects in a fasted state received a single dose of zoliflodacin 2 g (therapeutic), zoliflodacin 4 g (supratherapeutic), placebo, and moxifloxacin 400 mg as a positive comparator. Cardiac repolarization was measured by duration of the corrected QT interval by Fridericia’s formula (QTcF). At each time point up to 24 hours after zoliflodacin administration, the upper limit of the one-sided 95% confidence interval (CI) for the placebo-corrected change from the pre-dose baseline in QTcF (ΔΔQTcF) was less than 10 ms, indicating an absence of a clinically meaningful increase in QT prolongation. The lower limit of the one-sided multiplicity-adjusted 95% CI of ΔΔQTcF for moxifloxacin was longer than 5 ms at four time points from 1-4 hours after dosing, demonstrating adequate sensitivity of the QTc measurement. There were no clinically significant effects on heart rate, PR and QRS intervals, ECG morphology, or laboratory values. Treatment-emergent adverse events (AEs) were mild or moderate in severity and transient. This was a negative TQT study according to regulatory guidelines (E14) and confirms that a single oral dose of zoliflodacin is safe and well-tolerated. These findings suggest zoliflodacin is not proarrhythmic and contribute to the favorable assessment of cardiac safety for a single oral dose of zoliflodacin.