Glucose tolerance under unboosted atazanavir treatment

Treatment of HIV using antiretroviral drugs often results in metabolic disturbances. The protease inhibitor atazanavir has a less pronounced effect on the GLUT4 transporter and is characterised by a favourable lipid profile. In this study, Guffanti et al investigate what effect switching to unboosted atazanavir for 24 weeks has upon the oral glucose tolerance of patients whose current HIV treatment has caused metabolic disturbances. Twenty-one patients were included for analysis, with a median of 6.42 years previous exposure to antiretroviral therapy. The metabolic analysis included fasting plasma glucose, serum insulin, C-peptide, triglycerides and cholesterol; CD4+ cell count and HIV-RNA were assessed. Measurements were taken at baseline and weeks 4, 12 and 24. The homeostasis model assessment of insulin sensitivity and β-cell function showed no significant change after unboosted atazanavir treatment, though there were small changes in favourable directions for each. The group identified a significant improvement in lipid profiles when comparing baseline to week 24 measurements; the 120-min glucose level and an OGTT-based index of insulin sensitivity were also reduced significantly. There were few adverse events associated with the treatment and HIV replication was effectively controlled. The study concludes that unboosted atazanavir can have favourable effects on metabolic parameters compared to other PIs. They identify a need for randomised studies in a larger patient group over a longer period of time. Monica Guffanti, Andrea Caumo, Laura Galli, Alba Bigoloni, Andrea Galli, Geneviéve Dagba, Anna Danise, Livio Luzi, Adriano Lazzarin and Antonella Castagna. Switching to unboosted atazanavir improves glucose tolerance in highly pretreated HIV-1 infected subjects. European Journal of Endocrinology 2007 156 503-509.