Tafenoquine at therapeutic concentrations does not prolong fridericia-corrected QT interval in healthy subjects

Tafenoquine is being developed for relapse prevention in Plasmodium vivax malaria. This Phase I, single‐blind, randomized, placebo‐ and active‐controlled parallel group study investigated whether tafenoquine at supratherapeutic and therapeutic concentrations prolonged cardiac repolarization in healthy volunteers. Subjects aged 18–65 years were randomized to one of five treatment groups (n = 52 per group) to receive placebo, tafenoquine 300, 600, or 1200 mg, or moxifloxacin 400 mg (positive control). Lack of effect was demonstrated if the upper 90% CI of the change from baseline in QTcF following supratherapeutic tafenoquine 1200 mg versus placebo (ΔΔQTcF) was