Immune hyperactivation in immunodiscordant patients can induce residual HIV replication and limit CD4 T cell recovery. We assessed the impact of raltegravir intensification on CD4 T cell recovery and viral persistence.

We performed a randomized, controlled, pilot trial. Patients with CD4 T cell counts <350 cells/mm³ despite suppressive antiretroviral therapy were randomized (2 : 1) to intensify with raltegravir (intensified arm, n = 30) or to continue with the same regimen (control arm, n = 14) for 48 weeks. Then, the control individuals intensified their treatment for 24 weeks (delayed-intensification arm). We analysed changes in CD4 T cell counts, total and episomal HIV DNA in peripheral blood mononuclear cells and predictive factors for response.

Raltegravir intensification induced a rapid increase in CD4 T cell counts (week 12) (P = 0.007), although this was not sustained over time. Control patients maintained constant but slow increases in CD4 T cell counts (present in the pre-study period), reaching CD4 T cell counts similar to those of patients in the intensification arm at week 48. This effect was confirmed by the analysis of the delayed-intensification arm. Proviral DNA levels remained stable in both arms over time; episomal DNA forms and ultrasensitive plasma viral load were barely detected during the study. Increases in CD4 T cell counts were associated with low baseline CD95 expression in CD4 and CD8 T cells (P = 0.020).

Raltegravir intensification modestly impacts viral dynamics and induces a rapid but limited gain in CD4 T cell counts in immunodiscordant patients. Residual viral replication does not seem to be the main cause of unsatisfactory CD4 T cell recovery in these patients.