A randomized controlled trial investigating the efficacy and safety of switching from a protease inhibitor to nevirapine in patients with undetectable viral load.

OBJECTIVE

To assess the antiviral efficacy and safety of switching from a protease inhibitor (PI) to nevirapine in patients with long-term HIV-1 RNA suppression on PI-containing regimens, and to assess its influence in the adherence to treatment.

METHODS

In an open-label multicentre study, 160 HIV-infected patients with undetectable viral load for at least 6 months on a PI-containing regimen were randomized to either continue with their PI regimen (n=79) or replace PI with nevirapine (n=81). Clinical assessment included plasma HIV-1 RNA, blood chemistry, haematology, lymphocyte counts and adverse events reports. Adherence to treatment and lipodystrophy syndrome were assessed by patient self-reporting.

RESULTS

Treatment efficacy was equivalent in the two arms, for patients with viral loads either above or below 100 000 HIV-1 RNA copies/mL. The increase in CD4 cell count was significant in both arms (P<0.00001) but the average CD4 cell count at 48 weeks was slightly higher in the nevirapine arm (596 vs. 569; P=0.1588). The number of patients with severe hypertriglyceridaemia (>400 mg/dL) after 48 weeks of treatment decreased in the nevirapine arm (from 11 to six), but increased in the PI arm (from four to 11) and led to treatment discontinuation in two patients. Lipodystrophy changes increased in 15% of patients in the PI arm but decreased in 4% of patients in the nevirapine arm. Finally, although adherence was similar in the two arms, patients reported that it required significantly less effort to stay on treatment in the nevirapine arm. Conclusions The results indicate that switching from PI to nevirapine is as effective as continuing with PI for maintaining viral control, even in patients with baseline viral load above 100,000 copies/mL. In addition, reductions in hypertriglyceridaemia and lipodystrophy and in the effort required to stay on treatment were observed.