Relationships Between the Use of Antimalarial Drugs in Pregnancy and Plasmodium Falciparum Resistance

Plasmodium falciparum resistance to chloroquine (CQ) and sulfadoxine-pyrimethamine (SP) continue to spread, impeding control of this important disease. CQ and SP are still the most commonly used antimalarial drugs for malaria prevention during pregnancy and might be made less effective by resistance. However, the treatment and prophylaxis regimens used may also create conditions for selecting resistant malaria parasite strains. A better understanding of the relationships between chemoprophylaxis regimens and resistance would be helpful to improve chemoprophylaxis of malaria in pregnancy.

This work aims to improve the use of chemoprophylaxis in pregnancy by determining whether there is a relationship between the use of standard prophylactic regimens with CQ and SP and the occurrence of P. falciparum resistant strains in pregnant women. The study consists of 2 parts. The first part is a randomized trial comparing 3 chemoprophylactic treatment groups: - weekly CQ after initial presumptive CQ treatment, - CQ intermittent presumptive treatment given as a standard dose at 2nd and 3rd trimester, respectively and SP intermittent presumptive treatment given as a single dose at 2nd and 3rd trimester, respectively. These treatment groups will also be compared to a group of women delivering at the same health centre but who have not been participating in the study. The second part will be a clinical trial for assessment of clinical and parasitological efficacy of CQ and SP treatment in pregnant women presenting with uncomplicated malaria attacks.

The study will be conducted from October 2002 to March 2005 in a health centre of Ouagadougou, Burkina Faso where malaria transmission is seasonal and resistance to CQ and SP is low.