EFFICACY AND SAFETY OF ATAZANAVIR/RITONAVIR THERAPY IN A COHORT OF TREATMENT-EXPERIENCED PATIENTS

Background: Atazanavir (ATV) based regimens are generally well tolerated and seem to have a better metabolic profile than other PIs and NNRTIs based treatment. Few study assessed safety and effectiveness of ATV/r regimens for more than 2 years. Aim of this study is to describe efficacy and safety of ATV/r based regimens in a cohort of experienced patients treated for a long period of time. Methods: Patients switched to ATV300/r based regimen after at least 6 months of any other HAART therapy were enrolled in a retrospective study. We evaluated the proportion of patients maintaining HIV RNA \50 copies/ml, median increase of CD4 cell count, total cholesterol and triglycerides, liver transaminases, total bilirubin at the time of starting the ATV/r therapeutic regimen and after 1–4–8–12–24–36–48–60 months respectively. More frequent side effects and causes for discontinuation were also described Results: A total of 107 patients were evaluated; 62 (57.9%) were male, median age 45 (IQR 40–54) years, 55% heterosexuals, 24% MSMs, 21% IVDUs. 32% were HBV and/or HCV coinfected. Median time from HIV diagnosis was 11 years (IQR 5–15). Median length of HAART was 8 (IQR 4–11) years; median number of line of treatment was 4 (IQR 2–5). Before switching to ATV/r, 46% were on PI/r based treatment, 30% on NNRTI, 15% on PI unboosted and 9% on triple NRTI. At baseline median CD4 cell count was 341 (IQR 237–537) cells/ll, median HIV RNA viremia log 2.45 ± 1.47 copies/ml; 58% had HIV RNA\50 copies/ml. Median total cholesterol (TC) was 205 (IQR 171–269) mg/dl, 55% with more than normal value, median triglycerides 174 (IQR 116–315) mg/dl, 59% with more than normal value. After 12, 24, 36 months of treatment median CD4 cell count was 449 (IQR 300–615), 482 (IQR 354–700), 493 (IQR 368–773) cells/ll respectively. At the same times 83, 86, 79% of patients on treatment had HIV RNA\50 copies/ml. After 12 months 57% had altered TC value, 51% altered triglycerides. Patients with elevated bilirubinemia ([1.5 mg/dl) were 83, 84, 73% after 4, 8 and 12 months of treatment. After a median time of follow up of 40.6 months (IQR 24.3–59.8) 17% stopped the treatment. The most frequent causes for discontinuation were virological failure (8.5%) patient’s choice (5.7%) toxicity (2.8%). Conclusions: In a clinical real life setting ARV regimens based on ATV/r showed sustained virological response also after 36 months of treatment in an high proportion of patients. Treatment was generally well tolerated and safe although just few patients achieved a significant reduction of lipids levels. Hyper-bilirubinemia was frequent but never caused discontinuation.