This study will investigate the effect of Tafenoquine (TQ) 150 mg tablet ageing (dissolution profiles) on human exposure of TQ comparing the relative bioavailability of TQ from tablets exhibiting different dissolution profiles in healthy subjects. This is a single-centre, 2-arm, randomized open-label, parallel-group study in healthy subjects. All subjects will arrive in the unit approximately 24 hours prior to dosing and will be discharged after the 72-hour post-dose assessments are completed. Subjects will return for outpatient visits on Days 7, 14, 21, 28, and 56 after dosing. A total of 14 subjects (n=7 subjects in each arm) are planned to be enrolled. All subjects will receive a single dose of study medication (2x150 mg TQ tablets + 30 mg TQ SIL in solution) and participate through a 56-day post dose follow-up visit. To enable the application of peripheral microsampling in planned paediatric studies, a comparison of the measured pharmacokinetic (PK) exposure via peripheral blood collection (via microsampling) to venous collection will also be performed in this study.