The present Phase IIa study aims to confirm, in patients, the observed activity of MMV390048 against P. falciparum in pre-clinical models and the human IBSM human challenge model, and to determine the activity against P. vivax malaria in patients, both over 14 and 28 days. Additional aims are to characterise the safety of MMV390048 in patients. Patient safety will be monitored for up to 35 days post-dose including pharmacokinetic assessments. The study will investigate descending single doses of MMV390048 in response to results obtained in the first cohort/dose in each malaria sub type.~The results of this trial will identify active, well tolerated doses for investigation in combination with a partner drug within a Phase IIb clinical trial.~Preclinical studies using SCID mice inoculated with P. falciparum-infected red blood cells link doses and exposures to the efficacy of MMV390048.38 The active dose in the SCID model causing maximum effect (ED90) against the parasites is 1 mg/kg/day. The MPC derived from the SCID data was 39 ng/ml.39 A human dose for the treatment of P. falciparum was sought that could maintain blood concentrations above 39 ng/ml (100 nM) for 8 days. Assuming linear pharmacokinetics and based on observed data from the Phase I exploratory formulation study in human volunteers, a dose of approximately 20 mg would be estimated to achieve the pharmacodynamic target drug concentration in humans based on the preclinical efficacy data generated in the SCID mice model. For new antimalarial drugs the translation of a predicted efficacious dose from the SCID mouse to the human challenge model and in turn to the treatment of acute, uncomplicated P. vivax or P. falciparum is unknown. To minimise the risk to patients and to ensure the highest probability of success, the maximum safe dose (as determined in healthy volunteers) that maintains a toxicokinetic safety margin to the repeat dose studies was selected for the first cohort in this study. This dose is expected to exceed the predicted MPC on Day 8 and provide significant target coverage at the site of action.
The present proof-of-concept Phase IIa study aims to confirm, in patients, the observed activity of MMV390048 against P. falciparum in pre-clinical models and the human Induced Blood-Stage Malaria (IBSM) challenge model, and to determine the activity against P. vivax malaria in patients, both over 14 and 28 days. Additional aims are to characterise the safety of MMV390048 in patients. Patient safety will be monitored for up to 35 days post-dose including pharmacokinetic assessments. The study will investigate descending single doses of MMV390048 in response to results obtained in the first cohort/dose in each malaria sub-type. The results of this trial will identify active, well-tolerated doses for investigation in combination with a partner drug within a Phase IIb clinical trial.