Tafenoquine for primary and terminal prophylaxis of malaria in apparently healthy people: a systematic review

Primaquine was the only licenced antimalarial hypnozoiticidal drug available until recently. Now there is a newly approved alternative: tafenoquine. This review explores the efficacy of tafenoquine as a primary and terminal prophylactic agent in malaria. Multiple databases (Cochrane Central Register of Controlled Trials [CENTRAL], MEDLINE [PubMed], Embase [Ovid], Scopus, CINAHL [EBSCOhost] and LILACS) were searched for clinical randomised controlled trials that had used tafenoquine for prophylaxis without language or time restrictions. The last date of searching was 13 August 2018. For primary prophylaxis, tafenoquine reduced episodes of malaria compared with placebo, at a dose range from 50 mg weekly to 400 mg monthly in three trials conducted in Ghana, Kenya and Thailand. Two trials compared tafenoquine vs mefloquine, but malaria episodes were too few to reach a conclusion. For terminal prophylaxis, evidence from two trials suggest that tafenoquine may have equal or better efficacy compared with primaquine. All trials excluded pregnant participants or those with G6PD deficiency. Tafenoquine is effective for both primary and terminal prophylaxis. If used for primary prophylaxis it may continue to offer protection against vivax relapses after exposure has ended (as terminal prophylaxis).