Risks and benefits of replacing protease inhibitors by nevirapine in HIV-infected subjects under long-term successful triple combination therapy.

OBJECTIVE

To analyse the safety and efficacy of replacing the protease inhibitor (PI) by nevirapine (NVP) in subjects experiencing a long-term control of virus replication under a triple PI-containing antiretroviral combination.

DESIGN

Prospective evaluation of 138 HIV-positive subjects with plasma viral load below 50 HIV-RNA copies/ml for the last 6 months under a triple PI-containing regimen, who were randomly assigned to either replace the PI by NVP (n = 104) or continue on the same treatment (n = 34).

METHODS

Viral load, CD4 count, lipid profile, body-shape features, and quality of life parameters were all assessed at the time of randomization and every 3 months thereafter.

RESULTS

In an intent-to-treat analysis, a rebound in viral load occurred in 11% of subjects during the first 6 months after replacing the PI by NVP, whereas it appeared in 29% of those who remained on PI (P = 0.007). Treatment failure was related to lack of adherence in 90% of subjects on PI, but only in 22% of those receiving NVP (P = 0.006). The CD4 cell count outcome did not differ significantly comparing both groups at 6 months, although in patients receiving NVP an average reduction of 35 x 10(6) cells/l was observed, whereas in those on PI a positive trend was still recorded (+54 x 10(6) cells/l). At the time of randomization, 77.5 and 57.5% of subjects had cholesterol and triglyceride values above 200 mg/dl, respectively. No significant changes in the lipid profile were observed in any of the groups thereafter. Body-shape abnormalities were recorded in 70% of persons at the time of randomization, and partially reversed at 6 months in 50% of subjects who replaced the PI by NVP. A quality of life score recorded a significant improvement in subjects who switched to NVP compared with those who continued on PI.

CONCLUSIONS

The replacement of PI by NVP seems to be safe both virologically and immunologically, provides a significant improvement in the quality of life and in half of patients ameliorate lipodystrophic body-shape changes at 6 months, although serum lipid abnormalities still remain unmodified.