Krintafel (tafenoquine)

An antimalarial drug approved in the U.S. as Arakoda for malaria prevention and, as GSK's Krintafel, to prevent relapse of P. vivax malaria. It is now being studied in a Phase 2 trial (B-FREE) in people with chronic babesiosis and severe fatigue.

Tafenoquine is an 8-aminoquinoline that generates reactive oxygen species inside parasite-infected red blood cells, killing the Babesia parasites. Unlike atovaquone, it has a long half-life (about 15 to 17 days), which may help prevent relapse in patients with chronic or relapsing babesiosis.

Neither tafenoquine label carries a boxed warning. A G6PD blood test is required before anyone is prescribed tafenoquine, because people with G6PD deficiency can develop severe hemolytic anemia, and it is not given when G6PD status is unknown. Arakoda is not given to people with a history of psychotic disorders or current psychotic symptoms. Other label warnings cover methemoglobinemia, serious allergic reactions and harm to a G6PD-deficient baby during pregnancy or breastfeeding. Reported side effects include headache, dizziness, nausea, trouble sleeping, unusual dreams and anxiety. The drug stays in the body for weeks, with a half-life of about 15 to 17 days, so side effects can start late or last longer.^[1][2]

Dosing for the B-FREE babesiosis trial has not been publicly disclosed. For malaria, Krintafel is a single 300mg dose taken with chloroquine to prevent P. vivax relapse in people 16 and older. Arakoda for malaria prevention is 200mg a day for 3 days before travel, then 200mg weekly, with 1 last dose the week after leaving. In the expanded access program for persistent babesiosis, the registry lists 200mg a day with food on days 1 to 4, then weekly from day 11. The long half-life means fewer doses may be needed compared to standard babesiosis treatment.

Not for Babesiosis. Tafenoquine (Krintafel, Arakoda) has been FDA approved for other uses since 2018, but not for Babesiosis, where it is being studied in phase 2 clinical trials.

No. Tafenoquine is not FDA-approved for babesiosis; it is approved in the U.S. as Arakoda for malaria prevention and as GSK's Krintafel to prevent relapse of P. vivax malaria. For babesiosis it is in a Phase 2 trial (B-FREE), and as of September 2026, 60 Degrees Pharmaceuticals says it plans to ask the FDA to add babesiosis to the Arakoda label after reporting that all 3 evaluable expanded access patients were cured. ^[3][4]

B-FREE (NCT06656351) is an open-label Phase 2 trial of a 90-day tafenoquine regimen in about 40 adults with chronic babesiosis and severe fatigue, run at the Icahn School of Medicine at Mount Sinai and sponsored by 60 Degrees Pharmaceuticals. Its main measure is the change in fatigue at Day 90. The trial began in November 2025 and is recruiting; participants must have confirmed G6PD-normal status. ^[3]

G6PD testing is required before tafenoquine is prescribed, because people with G6PD deficiency can develop severe hemolytic anemia. Arakoda is not given to people with a history of psychosis. Other side effects include headache, dizziness, nausea, trouble sleeping, unusual dreams and anxiety, and the labels also warn about methemoglobinemia and allergic reactions. ^[1][2]

Tafenoquine is an 8-aminoquinoline that generates reactive oxygen species inside parasite-infected red blood cells, killing Babesia parasites. Unlike atovaquone, it has a long half-life of about 15 to 17 days, which may help prevent relapse in chronic or relapsing babesiosis and may mean fewer doses are needed. Dosing for the B-FREE babesiosis trial has not been publicly disclosed; for malaria Krintafel is a single 300mg dose and Arakoda is taken weekly after 3 daily loading doses. ^[3]