New: Low-dose Primaquine Efficacy and Safety Study Groups

Primaquine is the only commercially available antimalarial that prevents relapse in P. vivax and P. ovale malaria infections, and the only potent drug to kill mature gametocytes of P. falciparum, the form of malaria parasite that is transmitted between humans and mosquitos. As malaria-endemic countries move towards elimination, primaquine is becoming increasingly important, but concerns about its safety often limit its use.

Although the treatment is widely recommended, practitioners avoid prescribing it because in patients deficient in the enzyme, glucose-6-phosphate dehydrogenase (G6PD), an inherited enzyme deficiency common in malarious regions, red blood cells may rupture, a potentially serious side effect. In 2012, the WHO recommended the addition of a single low-dose of primaquine to an artemisinin-based combination treatment (ACT) to block transmission of gametocytes in areas facing artemisinin resistance or approaching malaria elimination. Due to the safety concerns, adoption of the WHO recommendation has been slow in these areas.

WWARN, in partnership with the University of Washington and the Malaria Elimination Initiative at the University of California, San Francisco, have initiated the new Low-dose Primaquine Efficacy and Safety Study Groups. These study groups will analyse data pooled from many individual studies to better define the efficacy and safety of the low dose protocol. These analyses will provide evidence to inform clinical and policy decisions on use of low-dose primaquine as an agent to block the transmission of malaria infection.

“With global ambitions to eradicate malaria by 2040, efforts of which are threatened by the emergence of artemisinin resistance throughout Southeast Asia, we are racing against time on multiple fronts. A full picture of the safety and efficacy profile of primaquine is urgently needed,” says Dr Ingrid Chen, Malaria Elimination Initiative, University of California, San Francisco. “Harnessing the power of pooled analysis, we expect to gain new insights on the safety and efficacy profile of low dose primaquine in preventing malaria transmission.”

There will be two analyses of the data used within this study group; one will address efficacy in the prevention of transmission and a second that will focus on safety.

“We are now inviting researchers to join in our Study Group and share their data and expertise. Together we can tackle this problem,” adds Professor Andy Stergachis from the University of Washington.

Find out more about the analysis and governance proposal and how to join this group. For further information, email clinical@wwarn.org.