Other reports indicate that polymorphically expressed monoamine oxidase A (Ariffin et al., 2019), CYP2C8 (Silvino et al., 2016), CYP2C19 (Ariffin et al., 2019; Chamnanphon et al., 2020), UDP-glucuronosyltransferase 2B7 (Chamnanphon et al., 2020), ATP-binding cassette transporter G2 (Chamnanphon et al., 2020), and solute carrier organic anion transporters 1A2, 1B1, and 2B1 (Sortica et al., 2017) may also contribute to PQ metabolism, and thus play a role in variable treatment outcomes for vivax malaria. Here, CYP2C8 is linked to Plasmodium vivax malaria.