Initiating antiretroviral therapy within an hour after birth, rather than waiting a few weeks, lowers the reservoir of HIV virus and improves immune response, early results from an ongoing study in Botswana, Africa, showed.
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Despite advances in treatment programs during pregnancy that prevent mother to child HIV transmission, 300-500 pediatric HIV infections occur each day in sub-Saharan Africa, Roger Shapiro, MD, MPH, said during a media teleconference organized by the American Association for the Advancement of Science. “Most pediatric HIV diagnosis programs currently test children at 4-6 weeks of age to identify infections that occur either in pregnancy or during delivery,” said Dr. Shapiro, associate professor of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health, Boston. “However, these programs miss the opportunity to begin immediate antiretroviral treatment for children who can be identified earlier. There are benefits to starting treatment and arresting HIV replication in the first week of life. These include limiting the viral reservoir or the population of infected cells, limiting potentially harmful immune responses to the virus, and preventing the rapid decline in health that can occur in the early weeks of HIV infection in infants. Without treatment, 50% of HIV-infected children regress to death by 2 years. Starting treatment in the first weeks or months of life has been shown to improve survival.”
With these benefits in mind, he and his associates initiated the Early Infant Treatment (EIT) study in 2015 to diagnose and treat HIV infected infants in Botswana in the first week of life or as early as possible after infection. They screened more than 10,000 children and identified 40 that were HIV infected. “This low transmission rate is a testament to the fact that most HIV-positive women in Botswana receive three-drug treatment in pregnancy, which is highly successful in blocking transmission,” Dr. Shapiro said. “When we identified an HIV-infected infant, we consented mothers to allow us to start treatment right away. We used a series of regimens because there are limited options. The available options include older drugs, some of which are no longer used for adults but which were the only options for children.”
The researchers initiated three initial drugs approved for newborns: nevirapine, zidovudine, and lamivudine, and then changed the regimen slightly after a few weeks, when they used ritonavir-boosted lopinavir, plus the lamivudine and zidovudine. “We followed the children weekly at first, then at monthly refill visits, and kept close track of how they were taking the medicines and the level of virus in each child’s blood,” Dr. Shapiro said.
In a manuscript published online in Science Translational Medicine on Nov. 27, 2019, he and his associates reported results of the first 10 children enrolled in the EIT study who reached about 96 weeks on treatment. For comparison, they also enrolled a group of children as controls, who started treatment later in the first year of life, after being identified at a more standard time of 4-6 weeks. Tests performed included droplet digital polymerase chain reaction, HIV near-full-genome sequencing, whole-genome amplification, and flow cytometry.
“What we wanted to focus on are the HIV reservoir cells that are persisting in the setting of antiretroviral treatment,” study coauthor Mathias Lichterfeld, MD, PhD, explained during the teleconference. “Those are the cells that would cause viral rebound if treatment were to be interrupted. We used complex technology to look at these cells, using next-generation sequencing, which allows us to identify those cells that harbor HIV that has the ability to initiate new viral replication.”
He and his colleagues observed that the number of reservoir cells was significantly smaller than in adults who were on ART for a median of 16 years. It also was smaller than in infected infants who started ART treatment weeks after birth.
In addition, immune activation was reduced in the cohort of infants who were treated immediately after birth.
“We are seeing a distinct advantage of early treatment initiation,” said Dr. Lichterfeld of the infectious disease division at Brigham and Women’s Hospital, Boston. “By doing these assays we see both virological benefits in terms of a very-low reservoir size, and we see immune system characteristics that are also associated with better abilities for antimicrobial immune defense and a lower level of immune activation.”
Another study coauthor, Daniel R. Kuritzkes, MD, chief of the infectious disease division at Brigham and Women’s Hospital, said the findings show “how critically important” it is to extend studies of HIV cure or long-term remission to infants and children. “Very-early intervention in neonates limits the size of the reservoir and offers us the best opportunity for future interventions aimed at cure and long-term drug-free remission of HIV infection,” he said. “We don’t think the current intervention is itself curative, but it sets the stage for the capacity to offer additional innovative interventions in the future. Beyond the importance of this work for cure research per se, this very early intervention in neonates also has the potential of conferring important clinical benefits to the children who participated in this study. Finally, our study demonstrates the feasibility and importance of doing this type of research in neonates in resource-limited settings, given the appropriate infrastructure.”
EIT is supported by the National Institutes of Health. Dr. Lichterfeld disclosed having received speaking and consulting honoraria from Merck and Gilead. Dr. Kuritzkes disclosed having received consulting honoraria and/or research support from Gilead, Merck, and ViiV.
SOURCE: Garcia-Broncano P et al. Sci Transl Med. 2019 Nov 27. eaax7350.