Sustiva Pregnancy Risks Include Microcephaly and Developmental Delays: Study

For pregnant women, a new study suggests that side effects of the HIV drug Sustiva may lead to a serious problems for their unborn child, increasing the risk of the baby being born with microcephaly and later experiencing developmental delays.

In findings published last week in the medical journal The Lancet, researchers from the Harvard T. H. Chan School of Public Health indicate that taking Sustiva during pregnancy may result in infants being 2 to 2.5 times more likely to have microcephaly, or abnormally small head size.

Sustiva (efavirenz) is an antiretroviral drug, which is used with other medications among HIV positive patients to control the infection and prevent acquired immunodeficiency syndrome (AIDS).

To evaluate the Sustiva pregnancy risk, researchers analyzed data from a follow-up study involving more than 3,000 infants born to HIV positive women who were taking different HIV therapy drugs. In the earlier study, the children’s head circumference was measured periodically from 6 months of age through 5 to 7 years of age.

In this new study, researchers used two classification systems to rank the children’s head growth. The first used standards developed by the U.S. Centers for Disease Control and Prevention for children under three years of age and the second was another set of standards for children older than three.

Children born to women on the HIV therapy drug Sustiva were 2 to 2.5 times more likely to have microcephaly, or small head size, compared to children born to women on regimens of other antiretroviral drugs. About 10% of infants whose mothers took Sustiva developed microcephaly. Comparatively, 5% of infants whose mothers took other HIV drugs developed microcephaly.

Exposure to all other types of HIV therapies was not linked to a higher risk of microcephaly, only exposure to Sustiva.

Children born with microcephaly to women taking Sustiva also had a higher risk of developmental delays compared to children with normal head size. They scored lower on standardized tests and had impaired development at ages one and five.

Microcephaly is a rare condition causing a baby’s head to be small and not fully developed. The brain has not developed properly during pregnancy or stopped growing after birth. It is typically present at birth and can be life threatening. There are treatments to help with the condition, but no known cure.

Microcephaly can lead to intellectual disability, poor motor function, poor speech, seizures or dwarfism.

As a result of the risks associated with using Sustiva during pregnancy, researchers emphasized the importance of exploring alternatives to combination therapy involving the drug.