The aim was to analyse data from two randomized controlled trials (RCTs) to determine if an adherence intervention programme for antiretroviral therapy (ART) resulted in a reduction in viral load. A cohort analysis of pre- and post-intervention viral loads and CD4 counts using paired analysis was undertaken on participants who received the intervention programme. Analysis was also undertaken on a control group. The intervention participants had an increase in mean CD4 count (450-478, P = 0.26), and a decline in log viral load (2.48-2.36, P = 0.056). The control group had a decline in mean CD4 counts (596-570, P = 0.53), and an increase in log viral load (2.09-2.11, P = 0.78). The use of an adherence intervention programme is associated with a decrease in mean viral load, which is in contrast to the control group that demonstrated an increase in viral load over time.