Reduced cytochrome P-450 (CYP) 2D6 activity and Plasmodium vivax malaria risk in Amazonians: A retrospective, population-based cohort study

Amazonians with an AS ≤ 0.25, but not necessarily those with intermediate CYP2D6 activity, have a greater risk of recurrence after a PQ-treated P. vivax infection and require alternative relapse suppression regimens for the radical cure of vivax malaria.