July 12, 2000
One of the concerns about switching from protease inhibitors to NNRTIs has been that, by doing so, we would sacrifice some of the potency of the antiretroviral regimens and that patients would develop virologic failure. There is a growing body of evidence that tells us that is not the case. In this poster, Cotton (who works for Boehringer Ingelheim) reviewed eleven studies published or presented at international meetings in 1998 and 1999 that reported PI replacement with NVP (NRTIs were also changed in some cases).
A total of 370 HIV-suppressed patients who switched therapy were identified. In an on-treatment analysis at three and six months 281/303 (93%) and 176/204 (86%) patients respectively had maintained undetectable viral loads. The entry criteria was not the same in all studies, and some included patients with multi-nucleoside experience, so results are not directly comparable to other studies presented in this and other meetings in a more controlled population. In general, nevirapine is very well tolerated except for patients who develop a rash -- which in this composite analysis, had a frequency of only 4%. During this meeting we also learned that prednisone does not prevent rashes associated with nevirapine (see poster WePpB1378). Metabolic parameters improve quickly after the switch, and although a head-to-head comparison has not been performed with efavirenz, nevirapine seems to be more "lipid-friendly." The practical implication of this and other switch presentations is that our fears about lack of potency of some NNRTI-based regimens are not justified.