Long-term response to highly active antiretroviral therapy with lopinavir/ritonavir in pre-treated vertically HIV-infected children

Background: Immune recovery after prolonged highly active antiretroviral therapy (HAART) with lopinavir/ritonavir has been reported in adults but not in children. Our study aimed at evaluating the long-term use of lopinavir/ritonavir among children in a clinical setting. Methods: We carried out a retrospective study on 69 protease inhibitor (PI)-experienced vertically HIVinfected children on HAART containing lopinavir/ritonavir. We analysed the changes in percentage CD41 cell count (%CD41) and viral load (VL) and identified prognostic factors to achieve CD41 >25% and undetectable VL (uVL) (� 400 copies/mL) by logistic regression. Results: During the first 2 years, we found an increase in the %CD41 in children with baseline CD41 between 0% and 15% and those with baseline VL 100 000 copies/mL. We found that %CD41 at baseline had a strong positive association with achieving CD41 >25% at 6, 12, 18, 24, 36 and 48 months of follow-up. We also found that length of PI use had a negative association with reaching CD41 >25% at 24 and 48 months and achieving uVL at 12 and 24 months. VL at baseline had a negative association with achieving uVL at 18 and 24 months.