Malaria is one of the largest global health problems. As per the World Health Organization (WHO), in 2008 there were an estimated 243 million cases and 863,000 malaria-related deaths. Malaria in pregnancy (MIP) is one of the most common causes of preventable mortality and morbidity in pregnant women and infants in sub-Saharan Africa with an estimated 30 million pregnancies at risk each year; resulting in about 200,000 infants and 10,000 women deaths annually.

MIP is associated with suboptimal pregnancy outcomes including low birth-weight (LBW) neonates, still births and miscarriages. LBW is the most predictive risk factor for neonatal mortality in sub-Saharan Africa. Thus reducing the incidence of LBW has broad public health implications. Important progress has been made in the control of MIP with the introduction of intermittent preventive treatment for malaria in pregnancy (IPTp). The WHO recommends IPTp during antenatal visits in high malaria transmission areas of sub-Saharan Africa. However, widespread sulfadoxine-pyrimethamine (SP) resistance especially in East and Southern Africa greatly limits the protective effect of IPTp. The development of safe, efficacious and affordable replacement of SP for IPTp is therefore an urgent priority.

The combination of azithromycin (AZ) and chloroquine (CQ) could potentially replace

SP for IPTp. AZ and CQ are synergistic against CQ resistant strains of P. falciparum and their co-administration has demonstrated efficacy, safety and tolerability in Phase 3 clinical studies in the treatment of malaria in non-pregnant adults in sub-Saharan Africa. In addition, AZ and CQ have been on the market for several years and have extensive safety records in adults, children and pregnant women. Both drugs have also been widely used in all trimesters of pregnancy and are considered safe in pregnant women as individual agents.

A fixed dose combination tablet formulation of AZ and CQ has been developed for IPTp and will be evaluated in this study. The study is a Phase 3 clinical trial aimed at demonstrating superiority of AZCQ over SP, the current standard of care for IPTp indication. It will be conducted primarily in East and Southern Africa where SP resistance is evident. The study will enroll asymptomatic pregnant participants during second trimester of pregnancy. This will be the pivotal study for regulatory submissions to European Medicines Agency (EMA) and to the national regulatory agencies in sub-Saharan African countries.