Effect of antiretroviral therapy (ARVT) on viral load (VL) in pediatric HIV infection

Recent availability of VL monitoring and multiple ARVT have ushered in a new era of medical management in patients (pts) with HIV. Studies in adults have demonstrated dramatic reductions in VL following the use of newer ARVT. We analyzed our first experiences in utilizing VL monitoring in a pediatric clinical setting, to examine the effect of changing ARVT on VL in children. VL was measured by the Roche-Amplicor PCR HIV Monitor Test. Of pts 1-13 yrs who had at least one VL between 7/96 - 12/96, 6 pts had a change in ARVT 4 weeks prior to the first VL (C), 23 pts had change 4-12 weeks prior to VL (B), and 35 had ARVT change >12 weeks prior to VL (A). Mean ± SD VL (copies/ml) and CD4 index (CD4 count/ 50% for age) were compared between these 3 groups. Viral Load CD4 Index p values (for VL) A 180,760±229,530 .42±37 A v B: <.07 B 61,573±68,893 .39±.36 B v C: <.05 C 7,322±7,643 .46±.35 A v C: <.07 Fifty pts had 76 follow up VLs during the same period. One drug change (n=5) produced a mean log fall of .84, 2 drugs (n=8) -1.27, and 3 drugs (n=3) change -1.77 log fall in VL. The change to AZT+3TC or DDI (n=3) resulted in 1.09 log drop, a change to 3TC+D4T -1.37 and 2 nucleoside analogs + 1 protease inhibitor -1.43 log fall. Significantly lower VL with no change in CD4 counts were measured in HIV infected children with a recent change in ARVT. Greater troughs in VL response were seen with combination therapy changes and with the use of newer ARV drugs. VL is a useful tool to assess ARVT response in children with HIV infection.