Plasmodium falciparum clearance is pitting-dependent with artemisinin-based drugs but pitting-independent with atovaquone-proguanil or mefloquine Short tittle: Drug-specific pitting in malaria.

Pitting, the removal of dead parasites from their host erythrocyte, has been studied in patients with severe malaria treated parenterally with quinine or artesunate, and was recently shown to contribute to delayed hemolysis, a frequent adverse event of artesunate. We quantified pitting in 81 travelers treated with oral antimalarial therapy. Pitting rate was high (55.8%) with artemisinin-based combinations, but lower than 10% with the non-artemisinin drugs quinine, mefloquine and atovaquone-proguanil. This may, in part explain the slower parasite clearance in patients treated with antimalarial drugs lacking an artemisinin component, as well as the absence of post-treatment hemolysis with these drugs.