CD4 and hyperlipidemia: The results of this study indicate that in hyperlipidemic, virologically suppressed, immunocompetent antiretroviral-experienced patients (HIV-1 RNA <50 copies/mL, CD4+ counts >500 cells/mm3), substituting abacavir for hyperlipidemia-associated PIs in HAART regimens improves lipid profiles and maintains virologic suppression over a 28-week period.