S did not count as first-line failures. The decision to switch to a second-line bPI-containing regimen for first-line failure was based on clinical criteria in both groups (new/ recurrent WHO 4 event (per-protocol); or single or multiple WHO 3 events at clinician discretion), or confirmed CD4,100 cells/ mm3 on ART (,50 cells/mm3 before July 2006) for LCM. Switching was discouraged before 48 weeks