Update: Intermittent preventive treatment regimens for malaria in HIV‐positive pregnant women

26 Sep 2024

Drugs to prevent malaria in HIV‐positive pregnant women

Key messages

• For HIV‐positive pregnant women, adding an antimalarial drug (such as mefloquine or dihydroartemisinin/piperaquine) to usual infection‐prevention treatment for people with HIV (daily cotrimoxazole):

‐ probably reduces the risk of the mother being infected with malaria when she delivers her baby;

‐ probably reduces malarial infection in the placenta;

‐ probably does not affect the risk of losing the baby before delivery or after birth, or of the baby having a low birthweight.

• Although mefloquine, when added to daily cotrimoxazole, probably reduces the risk of malaria infection in HIV‐positive women, it probably increases the risk of mother‐to‐child HIV transmission and may have a higher risk of negative drug reactions.

• Dihydroartemisinin/piperaquine, when added to daily cotrimoxazole, probably reduces the risk of malaria in the placenta of HIV‐positive pregnant women. It probably makes no difference to the risk of low birth weight or losing the baby before or after birth, or the risk of minor side effects, such as vomiting.

Why is malaria prevention in HIV‐positive pregnant women important?

HIV‐positive pregnant women are vulnerable to malaria. Having both malaria and HIV can make malaria worse in pregnancy, increasing the risk of health complications for women and their babies. Daily intake of a drug called cotrimoxazole is recommended to prevent infections in people with HIV, including pregnant women, in many countries where malaria is common. The drug that is recommended to prevent malaria in pregnancy, sulfadoxine‐pyrimethamine, cannot be taken by women on cotrimozaxole because of potential negative interactions between the two drugs.

What did we want to find out?

We wanted to know if antimalarial drugs currently available are effective and safe when used for preventing malaria in HIV‐positive pregnant women. This is an update of a Cochrane Review published in 2011.

What did we do?

We searched for studies that investigated the benefits and harms of antimalarial drugs used for prevention of malaria among HIV‐positive pregnant women. We combined the results of these studies.

What did we find?

We found 14 studies with 4976 HIV‐positive pregnant women. The studies were conducted between 2002 and 2023 in sub‐Saharan African countries: Benin, Central African Republic, Gabon, Malawi, Mozambique, Nigeria, Kenya, Tanzania, Togo, Uganda, and Zambia. The studies tested nine comparisons of different drug regimens.

What are our main results?

Adding an anti‐malarial drug such as mefloquine or dihydroartemisinin/piperaquine to daily cotrimoxazole probably reduces the risk of malaria infection in the mother's blood at delivery and in the placenta. It probably does not increase or decrease the risk of having a baby with low birth weight, or of losing the baby before or after birth. It probably does not increase or decrease the mother's risk of anaemia (i.e. low level of iron in the blood). We do not know if it has any effect on the risk of malarial parasites in the baby's umbilical cord.

Although mefloquine probably reduces the risk of malarial infection, it probably increases the risk of mother‐to‐child HIV transmission and may be more likely to cause negative drug‐related effects, when compared to daily cotrimoxazole alone.

When we looked separately at the studies that evaluated dihydroartemisinin/piperaquine, we found that dihydroartemisinin/piperaquine added to daily cotrimoxazole probably does not reduce the presence of the Plasmodium parasites in the mother's blood at delivery or her risk of anaemia, but it reduces malarial infection in the placenta. It probably does not increase or decrease the risk of low birth weight, or of losing the baby before or after birth. Dihydroartemisinin/piperaquine plus daily cotrimoxazole may not increase the risk of mother‐to‐child HIV transmission, compared to daily cotrimoxazole alone, and may not increase the risk of negative side effects from taking the drug.

What are the limitations of the evidence?

In terms of routine preventive treatment for HIV‐positive women (daily cotrimoxazole) plus any other drug (mefloquine or dihydroartemisinin/piperaquine), we are confident in the evidence regarding maternal anaemia at delivery. We are moderately confident in the evidence regarding presence of parasites in the mother's blood and placenta, babies born with low birth weight, and stillbirths and spontaneous abortions. It is possible that people in one of the studies were aware of who had received each drug regimen, which could have affected the study results. We are less confident in our results for presence of parasites in the cord blood and the risk of the baby dying after birth, because the results from the studies varied widely.

In terms of routine preventive treatment (daily cotrimoxazole) plus dihydroartemisinin/piperaquine specifically, we are confident in the evidence regarding malaria infection detected by the presence of parasites in the mother's placenta. We are moderately confident in the evidence regarding presence of parasites in the mother's blood, maternal anaemia at delivery, babies born with low birth weight, stillbirths and spontaneous abortions, and infant deaths. We are less confident in our results for the drug's side effects, and HIV transmission from mother to baby.

How up to date is this evidence?

The review authors searched for studies up to 31 January 2024.

Malaria Maternal and child health HIV/AIDS