Guidance for Using Tafenoquine for Prevention and Antirelapse Therapy for Malaria — United States, 2019

Julia C. Haston, MD; Jimee Hwang, MD; Kathrine R. Tan, MD

Disclosures

Morbidity and Mortality Weekly Report. 2019;68(42):1062-1068. 

In This Article

Discussion

This guidance regarding use of tafenoquine for both prophylaxis of all species of malaria and antirelapse therapy for P. vivax is consistent with FDA labeling. Recommendations for PART and antirelapse therapy of P. ovale are off-label. It is not feasible to conduct adequately powered clinical trials for P. ovale malaria because of its relatively low incidence. Therefore, evidence for efficacy against P. vivax was extrapolated to P. ovale.

For persons with contraindications to tafenoquine, other antimalarial options for malaria chemoprophylaxis and radical cure can be considered. There are several other options for chemoprophylaxis, each with its own contraindications and warnings, which can be used depending on the patient and drug-resistance in the areas of travel. These include atovaquone-proguanil, chloroquine, doxycycline, and mefloquine. For antirelapse therapy, the only alternative is primaquine. For nonpregnant persons with borderline or intermediate G6PD deficiency requiring antirelapse treatment, an alternative dosing regimen of primaquine could be considered at 45 mg (base) once weekly for 8 weeks, with close monitoring and consultation with an infectious disease expert. Persons with severe G6PD deficiency will require antimalarials at prophylaxis doses for 1 year instead of an 8-aminoquinoline (i.e., primaquine or tafenoquine). Pregnant women with normal G6PD levels, requiring antirelapse therapy could be given chloroquine at chemoprophylaxis doses (500 mg salt once weekly) until after delivery, and then an 8-aminoquinoline, depending on whether the woman is breastfeeding and the G6PD status of the infant.

The approval of tafenoquine marks a notable advancement for the prevention of malaria and treatment of P. vivax and P. ovale. Its long half-life of 15 days allows for weekly prophylactic dosing during travel and a single dose for antirelapse therapy, which has the potential to increase adherence for both indications.[7,8] With two strengths of tafenoquine tablets available, it is important that clinicians ensure that the appropriate dose is used for each specific indication.

Malaria is a notifiable disease in the United States. CDC's National Malaria Surveillance System collects information about cases of malaria occurring in the United States, providing an opportunity to assess the use and clinical outcomes of tafenoquine. Postmarketing surveillance is being conducted to monitor the occurrence of adverse events. Adverse events related to tafenoquine should be reported voluntarily to FDA's MedWatch adverse event reporting system, and as part of routine reporting to CDC.

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