When to Treat: Can Antiretroviral Therapy Be Delayed in Older Children in Asia?
October 2011 - A clinical trial called PREDICT, conducted in Cambodia and Thailand, has shown that older HIV-positive Asian children with moderately suppressed immune systems may be able to delay starting antiretroviral therapy.1 Researchers followed 299 children between the ages of one and 12 to compare the health outcomes of those starting treatment at CD4 levels between 15 and 24 percent to those delaying until CD4 levels dropped below 15 percent.
After 144 weeks of follow-up, there was no significant difference between the groups of children in terms of the development of AIDS-defining illnesses or death. Both groups showed similar improvements in their CD4 levels and suppression of their HIV virus after starting antiretroviral therapy. Preliminary screening of the children's visual and motor development skills also did not show differences. However, starting treatment earlier led to faster growth (i.e., weight, height) and reduced episodes of certain HIV-related diseases (e.g., herpes zoster/shingles).
Pediatric HIV clinic, Hospital Likas, Malaysia
When interpreting these data, the study investigators pointed out that all children had already survived beyond the age of 12 months, which may be an indication that they were not at risk for the rapid disease progression that is seen in some children. They received CD4 monitoring every three months, allowing healthcare providers to start antiretroviral therapy as soon as CD4 levels fell below the threshold. In addition, only 15 percent of the children were under three years old, making it difficult to make conclusions about those in the younger age range.
Current World Health Organization guidelines advise starting antiretroviral therapy in all infected children under 24 months of age; at CD4 levels below 25 percent (or 750 cells/mm3) in children two to five years old; and at CD4 counts below 350 cells/mm3 in children older than five years.2 Although the PREDICT study raises the question of how the clinical experiences of children living with HIV in the Asia-Pacific may differ from other settings, these treatment initiation thresholds remain critical targets for regional pediatric HIV programs.
1. Puthanakit T, et al. Randomized clinical trial of immediate versus deferred antiretroviral therapy initiation in children older than one year with moderate immunodeficiency: The PREDICT Study. Abstract presented at the 6th IAS Conference on HIV Pathogenesis, Treatment, and Prevention, July 17-20, 2011, Rome, Italy – Abstract TULBPE 023.
2. World Health Organization. Antiretroviral Therapy for HIV Infection in Infants and Children: Towards Universal Access, 2010 revision.