Pediatric Studies Highlighted in Seattle at This Year’s CROI Conference
This past week, Seattle was host to the 19th annual Conference on Retroviruses and Opportunistic Infections, colloquially known as CROI. It is the largest North American conference on HIV/AIDS, and attracts more than 4,000 leading clinicians and basic scientists studying HIV and associated diseases for presentations and discussions of their latest results.
It was unusually sunny in Seattle for most of the week, and while the overall mood at the conference was positive, the week began under a cloud. We learned about the unfortunate passing of a leader in the fight against pediatric HIV/AIDS – Dr. Ed Handelsman, Chief of the Maternal, Adolescent and Pediatric Research Branch at the National Institutes of Health (NIH) Division of AIDS.
Ed tirelessly advocated for pediatric AIDS research and care for kids living with HIV, and he led with grace and humility. As if by design, and owing to his importance to the field, Ed’s name was mentioned throughout the conference. In the Tuesday morning session on “Treatment Issues in Women and Children” where the announcement of Ed’s passing was made, all of the presentations listed Ed in their acknowledgments. He will be sorely missed by all in our community.
Maternal and pediatric issues were again important at this year’s conference, and Foundation-supported scientists past and present were at the forefront. If there was an overarching theme for the research presented, the catchword might be adherence: adherence to the cascade of activities for prevention of mother-to-child transmission of HIV, adherence to antiretroviral drug regimens for prevention and/or treatment, and adherence to partners to reduce the risk of HIV infection.
In one of six prestigious plenary presentations at the conference, former Foundation International Leadership Awardee Dr. Dorothy Mbouri Ngacha of UNICEF spoke about elimination of mother-to-child transmission of HIV. Her presentation outlined how far we’ve come in reducing the risk of transmission – from up to 40% without interventions, to less than 2% with the interventions used in developed nations.
While we still have much work to do in the most affected nations of sub-Saharan Africa and elsewhere, progress is being made toward the global goal of reducing mother-to-child transmission to less than 5% by 2015. However, clear gaps remain in keeping pregnant women HIV-negative, and treating HIV-positive pregnant women who have low CD4 counts to address the inherent increased risk of transmission.
Also a high priority is ensuring complete adherence to the PMTCT cascade, beginning with HIV counseling and testing, and continuing all the way through to ensuring HIV-exposed infants get their antiretroviral drugs after birth and through the breastfeeding period to prevent transmission.
Dr. Landon Myer – who is the current Foundation International Leadership Award recipient, generously funded by the Stavros Niarchos Foundation – presented data from South Africa on the issue of loss to follow-up of HIV-positive pregnant women who have started antiretroviral treatment. Women who were pregnant at the time of treatment initiation experienced significantly less mortality than those who were not pregnant, but were significantly more likely to be lost to follow-up. This is an issue of lack of adherence to clinic visits and their drug regimens that clearly could lead to higher rates of transmission of HIV to their babies.
In the same session, Foundation operations research grantee Dr. Benjamin Chi of the University of North Carolina and the Center for Infectious Disease Research in Zambia (CIDRZ) presented findings looking at the field effectiveness of providing universal antiretroviral therapy to all pregnant women for PMTCT.
His study compared sites that offered the following PMTCT regimens:
- The Zambian standard of care for PMTCT for women who are not eligible for treatment: the drug AZT given to mothers beginning at 28 weeks of pregnancy, plus the drugs AZT and 3TC given to mothers for one week post-delivery, and single-dose nevirapine given to the infant at delivery and for a week after birth
- Antiretroviral therapy consisting of a three-drug combination regimen given to pregnant women beginning at 28 weeks and continuing through breastfeeding, regardless of a women’s CD4 count and her eligibility for treatment, and single-dose nevirapine given to the infant at delivery and for a week after birth
- The better, three-drug combination regimen prevented more infections in infants as expected. However, when loss to follow-up was included, the field effectiveness of the better regimen was reduced, and there was ultimately no significant difference between the groups in the study.
As many countries move toward better but more complicated regimens for PMTCT, these results show that attention must be paid to improving adherence and retention in care if the drugs are going to have the desired benefit.
As this year’s CROI conference showed, addressing these overarching issues of adherence will be critical to preventing new pediatric infections, and reaching our goal of an AIDS-free generation.
Jeffrey T. Safrit, PhD, is the Director of Clinical and Basic Research for the Foundation, based in Los Angeles.