The main goal was to compare clinical and immunological versus clinical, immunological plus viral load criteria for switching to second-line ART by comparing 48 week treatment outcomes, including survival rates, viral suppression, failure to thrive, and AIDS-defining illnesses for treatment experienced children randomized to two switching criteria.

The overall goal of the study was aimed at determining whether the use of the current WHO criteria alone (clinical and immunologic) to define treatment failure as the trigger for switching to second-line antiretroviral therapy leads to poorer 6 month and 12 month treatment outcomes when compared to combining clinical and immunologic parameters with viral load (VL) monitoring.

In addition the study aimed at obtaining plasma samples from treatment experienced children, for future resistance testing. The results of this study may help guide WHO and national pediatric ART programs on the need for routine VL monitoring for children initiating HAART in resource limited settings, where virologic tests including resistance testing are not readily available or affordable.

Inclusion Criteria:

• HIV-Infected Children, 1 year to 12 years
• ART experienced and enrolled in an existing treatment program that used clinical and immunologic criteria to monitor response to ART.

Exclusion Criteria:

• None