This paper presented a new class of antimalarial drugs that were identified through structure–activity relationships of previously known — albeit non-optimal — antimalarial drugs. Two compounds (ELQ-300 and P4Q-391, both quinolone-3-diarylethers) were highly active against Plasmodium falciparum and Plasmodium vivax and inhibited the parasite's mitochondrial cytochrome bc1 complex. Importantly, the compounds targeted the liver and blood stages of the parasite as well as the forms that are crucial for disease transmission. Further studies of ELQ-300 showed that it was orally bioavailable, metabolically stable and highly efficacious in blocking transmission of malaria to the mosquito vector in a rodent model of malaria.