GlaxoSmithKline and the Medicines for Malaria Venture are seeking permission to market single-dose tafenoquine in the US to prevent relapse of Plasmodium vivax malaria.

The application, which relates to patients 16 years of age and older, is based on data from the GATHER and DETECTIVE trials.

The Phase III DETECTIVE trial showed that a statistically significant greater proportion of patients treated with single-dose tafenoquine (60 percent) remained relapse-free over the six-month follow-up period than patients on placebo (26 percent).

The GATHER trial investigated a single-dose of 300mg tafenoquine on levels of haemoglobin when compared to a 14-day course of 15mg primaquine, and showed that the incidence of decline “was very low and similar between the two treatment groups”, at 2.4 percent versus 1.2 percent, respectively.

GSK and MMV note that, if approved, tafenoquine would be the first new medicine for the prevention of relapse of P vivax malaria in more than 60 years, “potentially addressing the need for a single-dose and effective medicine for this debilitating disease”.

“One of the greatest challenges for patients with P. vivax malaria is preventing relapses,” said Patrick Vallance, president of R&D at GSK.

“Being able to treat patients with a single dose of medicine would be an important step forward in ensuring efficacious treatment, thereby reducing the risk of relapse, particularly in areas with very limited healthcare infrastructure.”