Treague Limited, a Cambridge, UK based pharma company and MMV, are a month into the Phase I stage of clinical development of the single enantiomer, RS(+) mefloquine for the treatment of malaria. The comparative safety, tolerability and pharmacokinetics of RS(+) mefloquine and racemic mefloquine will be investigated in a dose-ascending, double-blind, active and placebo-controlled Phase I study in healthy subjects in the UK.