• Development of Grade 3 or 4 adverse events attributed to the study treatment [ Time Frame: Throughout study ] [ Designated as safety issue: Yes ]
  
• Suppression of HIV viral load to less than 400 copies/ml and 50 copies/ml at Week 16 [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
  
• Time to virologic failure at or after Week 16 [ Time Frame: Throughout study after Week 16 ] [ Designated as safety issue: No ]
  

Anti-HIV treatment options are limited for pediatric patients because combination therapies recommended for adults may not be appropriate for children or adolescents. Few PIs are available in formulations appropriate for pediatric patients, and complex dosing schedules and food requirements may be detrimental to treatment adherence. A once-daily regimen of the NRTIs ddI and FTC and the nonnucleoside reverse transcriptase inhibitor (NNRTI) EFV has been shown safe and well tolerated in adults. This study will evaluate the long-term safety and efficacy of a ddI, FTC, and EFV regimen in pediatric patients.

Patients will be followed for a maximum of 192 weeks; all patients will receive ddI, EFV, and FTC together once daily. Study visits will occur at study entry, Weeks 2 and 4, and every 4 weeks thereafter. Blood collection, medical history assessment, and a physical exam will occur at all visits; urine collection will occur at selected visits. Intensive pharmacokinetic (PK) studies will be done at Weeks 2 and 12 to determine if dose adjustments are required for any of the drugs. If virologic failure is determined, PK studies will be repeated 4 weeks after adjustments in therapy. Parents or guardians will be asked to complete treatment adherence questionnaires at some visits. Some patients may also be asked to participate in an additional PK study after Week 16 or week 96.