This study aims to investigate the concentration dependent effects of OZ439 on the clearance of P. falciparum parasites in patients, specifically the determination of an in-vivo minimum inhibitory concentration (MIC) of OZ439. Characterisation of PK-PD (Pharmacokinetic-Pharmacodynamic) relationships is essential for rational evidence based dosing. The adaptive investigation of a range of doses will provide the best chance of accurate PK-PD characterisation, allowing the observation of Plasmodium falciparum growth dynamics and the subsequent identification of MIC and MPC (minimum parasiticidal concentration). Additionally the tolerability and pharmacokinetics of OZ439 will be confirmed. The PK/PD relationship between OZ439 exposure and subsequent effects on parasitaemia will be investigated.