Tafenoquine successfully completes Phase IIb clinical trials

Study results published today in The Lancet

19 Dec 2013

The results of the Phase IIb study investigating tafenoquine plus 3 days of chloroquine for the treatment and prevention of Plasmodium vivax (relapsing) malaria have been published today in The Lancet.1Tafenoquine is in development with GSK and MMV.

While Plasmodium falciparum is the deadliest of malaria parasites, P. vivax has proven the most elusive to cure. It has a dormant liver form (the hypnozoite) that can reactivate any time between 3 weeks and several years – leaving its victims vulnerable to the effects of multiple relapses of malaria.

The Phase IIb study recruited more than 300 patients with confirmed P. vivax malaria from seven centres in Brazil, Peru, India and Thailand – some of the countries most severely affected by relapsing malaria. The study defined 300 mg as the optimal dose to take forward into Phase III, as this dose was found to have an acceptable overall benefit–risk profile.

 “Tafenoquine shows potential as a drug to prevent further episodes of relapsing malaria, and could be a key tool to control and eventually eliminate malaria,” said Dr Timothy Wells, MMV’s Chief Scientific Officer.

1. Llanos-Cuentas A et al. Tafenoquine plus chloroquine for the treatment and relapse prevention of Plasmodium vivax malaria (DETECTIVE): a multicentre, double-blind, randomised, phase 2 dose-selection study The Lancet (2013). doi:10.1016/S0140-6736(13)62568-4.