The AIDS Beacon™

On January 15, The National Institute of Allergy and Infectious Diseases (NIAID) announced a new clinical trial that examines additional regimens to reduce the risk of mother-to-child HIV transmission during breastfeeding.

This could potentially make breastfeeding safer for HIV-positive mothers and their children.

Science, as well as conventional wisdom, continues to affirm that mother’s milk is nature’s miracle food for infants, and researchers are looking for ways to make sure that breastfeeding is a viable option for every mother, even those with HIV.

Complex antiretroviral (ART) strategies are available in many parts of the world to reduce the risk of mother-to-child HIV transmission. This popular strategy, though, has not yet been compared with other simpler ART regimens, as the current trial attempts.

The trial, known as Promoting Maternal-Infant Survival Everywhere (PROMISE), is a multinational study, drawing volunteers from as many 18 nations. Investigators are seeking 7,950 HIV-infected women who are pregnant or have recently given birth and 5,950 HIV-exposed infants of these women.

Researchers from the International Maternal Pediatric Adolescent AIDS Clinical Trials network, the organization leading the study, are looking to attract volunteers from countries with differing ranges of AIDS-fighting resources.

Four distinct questions are being addressed by PROMISE. The first focuses on which strategy for reducing HIV transmission is more effective: administering a cocktail of three antiretroviral as soon as 14 weeks of gestation or beginning a regimen with zidovudine (Retrovir) at 14 weeks along with a single-use dose of Viramune (nevirapine) during labor.

The second question tries to gauge which method is more effective and safe in preventing mother-to-child HIV transmission during breastfeeding: ART for mothers or a daily regimen of Viramune for mothers and infants.

How well short-term ART curbs mother-to-child viral transmission during breastfeeding and pregnancy in HIV-infected mothers who do not yet need therapy is being evaluated as the third component of the trial.

Finally, PROMISE will look at nearly 2,300 HIV-exposed but uninfected infants under one year of age. This group will randomly be assigned treatment with a placebo or cotrimoxazole, an antibiotic, once a day. Researchers will look at whether cotrimoxazole decreases the infant’s risk for HIV infection and what, if any, side effects or bacterial resistance develops as a result of the drug.

Answers to these research questions may modify current recommendations. As recently as December of last year, the World Health Organization (WHO) changed its own recommendations regarding breastfeeding for HIV-positive mothers, stressing that breastfeeding can be a good option for all mothers, including those with HIV. Previous WHO guidelines suggested women begin ART at 28 weeks. Now WHO recommends that HIV-positive women start at 14 weeks and continue until the breastfeeding period ends, typically when the infant turns one year old (see related AIDS Beacon news).

What is becoming clearer is the substantial health boost that breastfeeding provides to infants and mothers. Breastfeeding benefits include easy-to-digest nutrition and protection from certain bacterial and viral infections for the infant, and research is beginning to find a link between lower incidences of certain types of cancers in mothers.

However, breastfeeding can also be a substantial health risk. In 2008 alone, 430,000 children were infected with the virus, and scientists believe most were exposed to the disease because of mother-to-child transmission. Rates of HIV infection resulting from mother-to-child transmission are especially prevalent in developing nations with limited access to water. In these areas, breastfeeding is often the only realistic option.

Results from PROMISE are expected in the next five to six years.

For more information, please the NIAID press release.