- Bijker, Else M;
- Schats, Remko;
- Obiero, Joshua M;
- Behet, Marije C;
- van Gemert, Geert-Jan;
- van de Vegte-Bolmer, Marga;
- Graumans, Wouter;
- van Lieshout, Lisette;
- Bastiaens, Guido JH;
- Teelen, Karina;
- Hermsen, Cornelus C;
- Scholzen, Anja;
- Visser, Leo G;
- Sauerwein, Robert W
- Editor(s): Borrmann, Steffen
Immunization of healthy volunteers with chloroquine ChemoProphylaxis and Sporozoites (CPS-CQ) efficiently and reproducibly induces dose-dependent and long-lasting protection against homologous Plasmodium falciparum challenge. Here, we studied whether chloroquine can be replaced by mefloquine, which is the only other licensed anti-malarial chemoprophylactic drug that does not affect pre-erythrocytic stages, exposure to which is considered essential for induction of protection by CPS immunization. In a double blind randomized controlled clinical trial, volunteers under either chloroquine prophylaxis (CPS-CQ, n = 5) or mefloquine prophylaxis (CPS-MQ, n = 10) received three sub-optimal CPS immunizations by bites from eight P. falciparum infected mosquitoes each, at monthly intervals. Four control volunteers received mefloquine prophylaxis and bites from uninfected mosquitoes. CPS-MQ immunization is safe and equally potent compared to CPS-CQ inducing protection in 7/10 (70%) versus 3/5 (60%) volunteers, respectively. Furthermore, specific antibody levels and cellular immune memory responses were comparable between both groups. We therefore conclude that mefloquine and chloroquine are equally effective in CPS-induced immune responses and protection. Trial registration: ClinicalTrials.gov NCT01422954.