It is now safe for HIV-infected mothers in good immune health, to give their baby breast milk without transmitting the virus to them, a new study has found.
The ongoing study-Promoting Maternal and Infant Survival Everywhere (PROMISE), found that taking a three-drug antiretroviral regimen during breastfeeding essentially eliminates HIV transmission by breast milk to their infants, while preserving the health advantages of breastfeeding for the infant.
The findings, presented recently, at the 21st International AIDS Conference (AIDS 2016) in Durban, South Africa, support current World Health Organization guidelines that recommend lifelong antiretroviral therapy for all pregnant and breastfeeding women living with HIV.
PROMISE investigators found that both three-drug maternal antiretroviral therapy and daily infant nevirapine were safe and effective at preventing HIV transmission during breastfeeding. Overall, infant mortality in the study was extremely low, with nearly all babies surviving their first year of life.
The researchers enrolled 2,431 pairs of HIV-infected mothers and their HIV-uninfected infants at clinical research sites in South Africa, Malawi, Tanzania, Uganda, Zambia, Zimbabwe and India between June 2011 and October 2014.
On average, the women were asymptomatic and had relatively high CD4+ cell levels — a marker of good immune system health.
The researchers randomly assigned the mothers and their newborns to one of two regimens. One regimen included triple-drug antiretroviral therapy for the mother that continued through the period of study follow up and daily doses of nevirapine for the infant until 6 weeks after birth. The second regimen consisted of triple-drug antiretroviral therapy for the mother until 1 week after delivery and daily doses of nevirapine for the infant beginning from the first week after birth and continuing through completion of study follow up. The participants were followed for 18 months or until the mother stopped breastfeeding (on average 15 months after childbirth), whichever came first.
The researchers found that maternal three-drug antiretroviral therapy, as well as infant nevirapine, offered protection against HIV transmission from mother to child. The rate of perinatal transmission did not differ between the two study arms — 0.3 percent at 6 months of age and 0.6 percent at 1 year of age. This is low compared to rates of transmission in the absence of any intervention. Without intervention, rates of HIV transmission from a HIV-infected mother to her child during either pregnancy, labor, delivery or breastfeeding historically have ranged from 15 to 45 percent, according to WHO.
Infant mortality in resource-limited countries can be high, but in this study, nearly 99 percent of babies lived to see their first birthday.
“HIV-infected mothers in low and middle income countries, who may not have access to alternative feeding methods, can be reassured that breastfeeding is a safe option for their infants,” said Nahida Chakhtoura, M.D., of the Maternal and Pediatric Infectious Disease Branch at National Institute of Child Health and Human Development (NICHD).
“The PROMISE team and the PROMISE mothers were gratified with the extremely low rates of infant infection and excellent infant survival with the use of maternal antiretroviral therapy,” said Protocol Chair Mary Glenn Fowler, M.D., M.P.H. “These results show the importance of mothers continuing to take antiretroviral therapy to reduce risk of mother-to-child transmission during breastfeeding.”
Infant nevirapine also offers a safe and effective alternative if the mother has difficulty adhering to or tolerating antiretroviral therapy, the researchers suggest.
Another component of PROMISE, also presenting results at AIDS 2016, followed 1,652 HIV-positive non-breastfeeding women with relatively strong immune system health who were randomly assigned to either continue antiretroviral therapy or stop antiretroviral therapy postpartum. While both groups of study participants showed similar, low rates of AIDS-defining and serious non-AIDS events, other HIV-related illnesses were significantly lower among the women who continued antiretroviral therapy. These findings provide further evidence from a large international randomized clinical trial of the benefits of antiretroviral therapy for women.
“These findings add to the considerable body of evidence confirming the benefits of antiretroviral therapy for every person living with HIV,” said Anthony S. Fauci, M.D., director of National Institute of Allergy and Infectious Diseases (NIAID) atNational Institutes of Health (NIH), USA. According to him, “Maternal antiretroviral therapy safely minimizes the threat of HIV transmission through breast milk while preserving the health advantages of breastfeeding, as the high infant survival in this study underscores.”
The new findings stem from a component of PROMISE that compares the safety and efficacy of two antiretroviral regimens for preventing mother-to-child transmission of HIV during breastfeeding. This component included mother-infant pairs living in resource-limited settings where breastfeeding is common and recommended for infant health. HIV-infected mothers in areas that lack safe, clean water may be encouraged to breastfeed because of the health benefits for the infant and the risk for infants from mixing formula with an unsafe water supply. Breastfeeding helps prevent malnutrition, and antibodies from breast milk protect babies against potentially life-threatening diarrheal and respiratory infections.