This low discontinuation rate contributed to the rates of success seen in both arms, with 87% of individuals having a viral load less than 400 copies/ml, and 82% and 81% less than 50 copies/ml at 48 weeks. The CD4 count rise was 169 cells in the TDF arm, and 167 cells in the d4T arm. There was no effect of viral load or CD4 count on the efficacy in each arm