Outcome of a Second-Line Protease Inhibitor-Containing Regimen in Patients Failing or Intolerant of a First Highly Active Antiretroviral Therapy [Bini T, et al. JAIDS 2000; 24: 115]: The authors from Milan investigated 263 patients who were given a new PI-containing regimen because the first regimen failed to decrease HIV viral loads by at least 1 log after two months (148 patients) or caused toxicity or intolerance (115 patients). During the subsequent follow-up period, which averaged 483 days, 154 patients (59%) discontinued the second regimen due to virologic failure in 51% or due to intolerance or toxicity in 33%. The authors conclude that patients who require a treatment change after the first regimen are at high risk for problems with a substitute regimen due to intolerance, toxicity or virologic failure. Comment: Experienced HIV providers will not be surprised by the results of this study. It is particularly important to note that 1/3 of failures with the rescue regimen were due to intolerance or toxicity. This point is emphasized because most studies of failures have dealt with virologic failure rather than failures due to drug intolerance or toxicity, and studies of rescue regimens have usually dealt with a selection based on established or predicted resistance profiles with possibly inadequate attention to tolerance as a major factor. posted 8/11/2000