However, research shows there’s a tradeoff between stopping the virus and the negative effects of powerful antiretroviral medications on the baby’s heart.

In two recent, unrelated studies, the drug lamivudine (Epivir) appears to have fewer serious side effects than other drugs when used to prevent mother-to-child HIV transmission.

Women with HIV who give birth and don’t pass the disease onto their children are benefiting from a miracle of modern medicine. But until now, doctors have not fully understood the long-term effects of these antiretroviral medications on babies.

In a study sponsored by the National Institutes of Health (NIH), a three-drug regimen using Epivir appeared to be safer than one that uses tenofovir (Viread), an independent data and safety monitoring board concluded.

Meanwhile, research set to be published in the January 2015 edition of the journal AIDS shows that Epivir doesn’t stress a baby’s heart as much as other antiretroviral drugs. The study concluded, however, that medications used to prevent HIV, in general, can lead to long-term heart problems in children.

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In findings from the ongoing Promoting Maternal-Infant Survival Everywhere (PROMISE) study, the NIH reported that a triple-therapy regimen of Epivir, zidovudine, and ritonavir-boosted lopinavir was safer than the triple-therapy combination Viread, emtricitabine (Emtriva), and ritonavir-boosted lopinavir.

Mothers taking the Epivir combination gave birth to HIV-infected babies only one-half of 1 percent of the time in the 3,500-women, randomized study. The Viread combination resulted in infant infections 0.6 percent of the time.

The Epivir combination also led to fewer serious adverse outcomes, such as a very low birth weight baby, very premature delivery, stillbirth, spontaneous abortion, and significant birth defects. However, both triple-therapy regimens led to less severe difficulties for newborns, such as birth weights below 5 pounds, 8 ounces, and delivery earlier than 37 weeks.

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Both triple-therapy regimens, in which women begin treatment as early as early as 14 weeks into the pregnancy, proved safer and more effective than an alternative known as “option A.” Option A involves giving women zidovudine early in pregnancy, a single dose of nevirapine (Viramune) during labor, and two weeks of Viread and Emtriva after delivery. This option is often used in resource-poor areas where the triple-drug regimen is simply too expensive.

The PROMISE study has enrolled women in India, Malawi, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe.

Dr. Steven Lipshultz, chief pediatrician at Children’s Hospital of Michigan and chair of pediatrics at the Wayne State University School of Medicine, conducted the study to be published in the journal AIDS. It already appeared briefly on the journal’s website as an “online first” feature.

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His research examined heart development and long-term function in 417 HIV-exposed but uninfected children and 98 unexposed children whose mothers had received antiretroviral drugs many years earlier.

Lipshultz found that while none of the HIV-exposed but uninfected children were sick from heart disease between two and seven years later, some had impaired heart muscle structure and function after being exposed to the medications.

Some medications proved more harmful than others. Epivir appeared to be the least harmful among the NRTIs, followed by Emtriva and Viread.

“Not only do these medications block the ability of a retrovirus such as HIV to grow and survive, but they also seem to have an effect not just on viruses but on the cells in the heart,” he told Healthline. “Five years later, some subjects had less healthy hearts, but not so unhealthy they’re sick.”

The U.S. Centers for Disease Control and Prevention is striving to reduce all transmission of HIV from mothers to children to less than 1 percent.

Lipshultz said a balance needs to be struck between reducing transmission and making sure the drugs that do so do not impair the life of the uninfected child down the road.

“The real measure of a successful treatment is over the course of a lifespan what the quality of life is for that child,” he said. “If we only have four or five years of long-term follow-up, it’s not enough to say there are no significant side effects because they are not sick, and that they are free and clear for the rest of their lives.”

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