• Virologic and Immunologic Responses in Children with Advanced HIV Disease on a New HAART Regimen (PACTG 366) (Poster 684)
  Authored by A. Kovacs, S. Burchett, M. Khoury, V.Carey, S. Pahwa, K. McIntosh, R. Oyomopito, E. Smith, L. Mofenson, and the PACTG 366 Team
  View the original abstract

HIV-infected children need salvage therapy just like everyone else -- perhaps even more so, since many had new agents added incrementally to failing regimens as new antiretrovirals were approved for pediatric use. This study assessed salvage therapy for 201 children and adolescents from 6 months to 20 years of age who had viral loads greater than 50,000 copies, <15% CD4 cells, CNS disease, or growth failure. The purpose of this study was to evaluate virologic and immunologic response to a change in therapy among children who were PI- and NNRTI-naive and -experienced. Virologic response (VR) was defined in modest terms as an 0.75 log (or greater) decrease in viral load; a complete virologic response was a viral load less than 400 copies.

In this highly exposed cohort, not unsurprisingly protease inhibitor-naive children were more likely to achieve a virologic response and more likely to have that response be durable compared to PI-experienced children (66% vs. 43%, p<0.01 for VR; 47% vs. 21.4%, p<0.01 for durability). Again, it is not surprising that higher baseline CD4 cell counts were a positive predictor of response, whereas higher baseline CD8 cell counts and greater degrees of T-cell activation predicted poorer outcomes. Although the majority of children achieved the goal of a modest decrease in viral load, being PI-naive was crucial to maintaining that response and to being able to achieve an undetectable viral load.

This study breaks no new ground -- we have been well aware that exposure to a new drug class is key to the treatment of experienced patients. It is interesting that lack of prior exposure to protease inhibitors was more valuable than lack of prior exposure to NNRTIs.