Bed nets have protected Mary Akye and her five children from malaria-carrying mosquitoes in Ghana.

A four-year study has shown that four available antimalarial treatments are safe to use in pregnancy.

The PREGACT study (PREGnancy Artemisinin-based Combination Treatments) compared four artemisinin-based combination treatments (ACTs), amodiaquine-artesunate (AQAS), dihydroartemisinin-piperaquine (DHAPQ), artemether-lumefantrine (AL), and mefloquine-artesunate (MQAS). Led by the Belgian Institute of Tropical Medicine Antwerp (ITM) and coordinated by Professor Umberto D’Alessandro, the study included women in Burkina Faso, Ghana, Malawi and Zambia.

A total of 3,428 pregnant women with malaria in the second and third trimester were randomly assigned to one of these four antimalarial treatments. The researchers concluded that all four treatments, which are already used in adults and children, were effective and safe. DHAPQ was found to be the most effective treatment for uncomplicated malaria in pregnancy, with good safety, and longer protection from re-infection after treatment. Dr Pedro Alonso, Director of the Global Malaria Programme at the World Health Organization, said: “Pregnant women in Africa are at increased risk of malaria infection and its harmful consequences for both themselves and their foetus. Identifying safe and effective treatment regimens is a priority for malaria control programmes.”

Few studies on antimalarial drugs have been carried out in pregnant women. As a high-risk group, pregnant women are excluded from most clinical trials, so information on the safety and efficacy of current antimalarials in pregnancy is scarce, especially in Africa. Professor D’Alessandro, director of the MRC Unit, The Gambia, and affiliated with the ITM and the London School of Hygiene and Tropical Medicine, said: “We hope that the use of these ACTs among pregnant women will now increase. “These results provide strong support for the use of ACTs in the second and third trimester of pregnancy and will help African countries in either confirming or changing their treatment guidelines for pregnant women with malaria. Even though ACTs are already recommended for pregnant women in the second and third trimester, some of them may still receive quinine, an old drug with many side effects.”

The study results also provide information on which treatment to use in different situations. For example, in regions where the malaria presence is intense, including Burkina Faso, women can experience several infections in a limited time span. In such cases, a treatment providing several weeks protection, such as DHAPQ, would be the best choice. Where transmission is less intense, other treatments could be used.  Professor Feiko ter Kuile, coordinator of the Malaria in Pregnancy Consortium, said: “The results of this trial, which is the largest comparative malaria treatment trial for pregnant women in Africa to date, is excellent news for policy makers and pregnant women as it shows that all four commonly used artemisinin-based antimalarial combinations appear safe and have excellent efficacy in treating malaria in this high risk group.”

The study was funded by the European and Developing Countries Clinical Trials Partnership (EDCTP) and the Bill & Melinda Gates Foundation.