(GLASGOW, 9 November 2010) Results from a European Observational Study, which included 1,294 antiretroviral (ARV)-experienced patients presented today at the Tenth International Congress on Drug Therapy in HIV Infection (HIV10), demonstrated a low rate of discontinuation and sustained virologic suppression with REYATAZ® (atazanavir)/ritonavir-based regimens over a follow-up period of up to five years.1
The aim of this study was to investigate the long-term outcomes of REYATAZ/ritonavir-containing regimens in ARV-experienced patients in a real-life clinical setting. The primary endpoint of the cohort study was the proportion of patients who remained on treatment over time by baseline HIV-1 RNA level (< 500 copies/mL and >= 500 copies/mL). Secondary endpoints were reasons for discontinuation, time to virologic failure (defined as either two consecutive HIV-1 RNA >= 50 copies/mL or one HIV-1 RNA >= 50 copies/mL followed by discontinuation) and long-term safety profile.1
The results of the study revealed that 56% of patients with baseline viral suppression (< 500 copies/mL) (n= 722) and 53% of those with detectable viral load (>= 500 copies/mL) (n= 540) remained on treatment after 3 years with a median time to discontinuation of 4 versus 3.6 years, respectively. The overall discontinuation rate in the study was low (43%) with the reasons for discontinuation including adverse events (11%), withdrawn consent (6%) and lack of efficacy (6%). After three years on a REYATAZ/r-based regimen, 75% of patients with baseline HIV-1 RNA levels < 50 copies/mL remained suppressed and 51% of patients with baseline HIV-1 RNA levels >=50 copies/mL achieved and maintained virological suppression.1
Long-term safety outcomes from this real-life study were consistent with data observed in clinical trials: diarrhoea (4%), renal and urinary disorders (3%), nausea (< 1%) and jaundice (< 1%) were reported. Discontinuations due to hyperbilirubinemia were infrequent (< 1%) and no new or unexpected adverse events were observed.1
"Prior to this cohort study, less was known about long-term outcomes and the length of time on treatment in experienced patients after switching", said Professor Jan van Lunzen, M.D., Ph.D. of The University Medical Centre Hamburg-Eppendorf in Germany. "This cohort study shows in a real-life setting that a significant proportion of treatment-experienced patients stayed on an atazanavir/ritonavir-containing regimen for up to five years", he added.
This real-life long-term cohort was a non-comparative, retrospective, observational study that collected data from three European databases (France DatAids; Germany KompNet; Sweden InfCare). Clinical data from 1,294 ARV-experienced adult patients who started an atazanavir/ritonavir-based regimen between October 2004 and March 2007 were collected every six months (maximum follow-up of five years). Patients were predominately male (74%); their median age was 43 years and 75% had prior exposure to protease inhibitors (PIs).