The proportion of subjects who discontinued study treatment due to adverse events, regardless of severity, was 3% in the Vitekta group and 4% in the raltegravir group. The most common adverse reaction (all Grades, incidence greater than or equal to 5%) in subjects receiving Vitekta in Study 145 was diarrhea. The most commonly reported adverse reactions (all grade) for Vitekta and raltegravir containing regimens, respectively were diarrhea (7% vs 5%), nausea (4% vs 3%) and headache (3% each).