Long-term efficacy and safety of protease inhibitor switching to nevirapine in HIV-infected patients with undetectable virus load.

BACKGROUND

Simplified highly active antiretroviral therapy (HAART) regimens are becoming widely used, particularly as a result of the side effects of and difficult compliance with protease inhibitor (PI) therapy. However, the long-term efficacy of HAART has not been properly assessed.

METHODS

We performed a prospective study of 110 patients infected with human immunodeficiency virus type 1 (HIV-1) with undetectable virus load who discontinued PI therapy and initiated therapy with nevirapine without changing nucleoside analogues. Reasons for switching were treatment simplification (45%), lipodystrophy (24%), renal problems (23%), and dyslipidemia (8%). HIV-1 load, CD4 cell count, and fasting biochemistry profiles were performed at the time of switching (baseline) and every 3-4 months thereafter. The aim of the study was to evaluate the long-term efficacy and safety of this combination.

RESULTS

Sixty-eight patients (61.8%) had a duration of follow-up of 3 years. The mean increase in the CD4 cell count after 3 years was 90 cells/microL (13.8% from baseline). Virus loads remained undetectable in all patients but 9 (8.2%). Triglyceride levels dramatically improved at 12 months (a 75% decrease; P<.02) and remained statistically significant over time (P<.04). The same occurred with serum cholesterol levels: there was an initial reduction of 25% (P<.02) and at the end of the follow-up period (P<.015). However, at the long-term evaluation, complete normalization of mean serum cholesterol and triglyceride levels could not be achieved. Sixteen patients (14.5%) had to stop therapy as a result of nevirapine-associated side effects.

CONCLUSIONS

The switching of a PI to nevirapine is a safe and well-tolerated option for maintaining long-term virological suppression and immunological control. Three years after starting nevirapine therapy, rates of hypercholesterolemia and hypertriglyceridemia improved, although normal cholesterol and triglyceride values were not achieved.