New drug combination could reduce malaria infection risk in pregnant women living with HIV

Researchers have tested a new combination of medications that could thwart resistance to common malaria drugs, significantly reducing the infection risk in pregnant women living with HIV.

The WHO estimates that 1 million women living with HIV in sub-Saharan Africa are also infected with malaria during pregnancy every year. At the same time, existing drugs are becoming less effective as malaria parasites become resistant to them.

The researchers from the Liverpool School of Tropical Medicine, Kenya Medical Research Institute, Kamuzu University of Health Sciences, and Malawi University of Science and Technology, unveiled this treatment in a collaborative study published earlier this month (12 January) in The Lancet.

The findings are applicable to not only areas with high malaria transmission, but also most importantly applies to areas with reported malaria-drug-resistance to cotrimozazole and fansidar.”

Simon Kariuki, Chief Research Officer, Kenya Medical Research Institute

They found that a monthly course of the antimalarial combination drug dihydroartemisinin–piperaquine added to a daily regimen of the antibiotic co-trimoxazole reduces the risk of malaria in pregnancy by 68 per cent.

Hellen Barsosio, assistant principal clinical research scientist at Kenya Medical Research Institute and lead author, said the drug combination is safe and well tolerated by pregnant women—which is important when a drug is given for prevention.

“These findings are very encouraging and could lead to a much-needed policy change that could make a real difference in improving maternal and newborn health in Africa,” she told SciDev.Net.

Drug resistance

In October 2017, the WHO Malaria Policy Advisory Committee highlighted the need for alternative medicines to prevent malaria in pregnant women living with HIV because of increasing drug resistance to medicines used for the prevention of malaria.

International malaria guidelines currently recommend daily co-trimoxazole to prevent malaria in pregnant women living with HIV in areas with high malaria transmission.

Co-trimoxazole, an antibiotic taken daily by people living with HIV to prevent opportunistic infections, also has some antimalarial properties similar to sulfadoxine–pyrimethamine, sold under the brand name Fansidar, which is recommended to prevent malaria in HIV-negative women in areas with high malaria transmission.

However, the challenges of malaria drug resistance, which impact Fansidar and weaken its ability to prevent malaria in HIV-negative women, also affect co-trimoxazole, Barsosio explains.

“Co-trimoxazole only provides partial protection against malaria for pregnant women living with HIV in areas of malaria-drug-resistance,” she told SciDev.Net.

Consequently, the WHO called for further research into drugs that could be used together with co-trimoxazole to prevent malaria in pregnant women living with HIV.

“Our study found dihydroartemisinin-piperaquine to be the most promising drug that can be safely combined with co-trimoxazole without side effects,” Barsosio said.

“It clears any existing malaria infections when taken and provides long-term protection.

“Our health care providers are also familiar with dihydroartemisinin–piperaquine and use it as second-line treatment for malaria.”

The researchers conducted a randomized controlled trial in pregnant women living with HIV in areas in Kenya and Malawi that have reported high malaria transmission and where parasites have demonstrated resistance to malaria drugs such as co-trimoxazole and Fansidar.

“This means the findings are applicable to not only areas with high malaria transmission, but also most importantly applies to areas with reported malaria-drug-resistance to co-trimozazole and Fansidar,” Simon Kariuki, Chief Research Officer, Kenya Medical Research Institute, and co-author, explains.

Joachim Osur, vice-chancellor at Amref International University in Nairobi, said the findings provide additional options in the fight against the twin tragedies of malaria and HIV on the continent.

“We in the medical fraternity appreciate these findings because malaria is a killer, and HIV is also a killer,” Osur told SciDev.Net.

“We need more options in the fight against these diseases, and that is what the findings provide.”

However, he added that pregnant mothers who are HIV positive still need to treat their infections—and other malaria prevention and treatment strategies must be maintained despite these findings.

“We only need to improve our medical treatment guidelines to co-opt these options,” he said.