If this is not your name, click here.
| | If this is not your name, click here. | | |
| | Contact Us | Order Now | Journals | Bookstore | Register a colleague | | |
| |  Boosted Atazanavir Effective in Lowering Viral Load in Patients With Advanced HIV: Presented at IAS By Ed Susman CAPE TOWN, South Africa -- July 23, 2009 -- Researchers suggested that the protease inhibitor atazanavir could successfully treat patients with advanced HIV infection. In a post hoc analysis of the CASTLE study, 96-week data that compared outcomes between atazanavir/ritonavir with lopinavir/ritonavir, scientists found that more discontinuations occurred among the lopinavir patients than the atazanavir patients when looking at those individuals with lowest baseline CD4-positive cell counts. "Atazanavir/ritonavir demonstrated high response rates across all CD4 cell count strata," reported Jonathan Uy, MD, Virologic Medical Strategy, Bristol Myers Squibb Research and Development, Plainsboro, New Jersey, at his poster presentation on July 20 at the 5th International AIDS Society (IAS) Conference on HIV Pathogenesis, Treatment and Prevention. "This subgroup analysis of CASTLE confirms that atazanavir/ritonavir is an effective and well-tolerated once-daily treatment that is appropriate to use in HIV-infected treatment-naïve patients," Dr. Uy said. In the CASTLE trial, 883 patients were recruited and 440 were assigned to receive atazanavir/ritonavir 330/100 mg once daily. In the open-label trial, the other 443 patients were assigned to receive lopinavir/ritonavir 400/100 mg twice a day. In addition, all patients were treated with fixed-dose tenofovir/emtricitabine 300/200 mg once a day. Overall, in findings from the 48-week data in the main study, 78% of the atazanavir patients and 76% of the lopinavir patients achieved suppression of HIV to undetectable levels. Dr. Uy's study sought to determine how well the drug combinations were handled by patients with low CD4-positive cell counts (<50 cells/mm3) or those with high viral loads in excess of 100,000 copies/mL. Both treatment regimens appeared to reduce the virus to undetectable levels at similar rates. For example, in the as-treated population, about 91% of the 143 patients on atazanavir and 85% of the 131 patients on lopinavir who at baseline had viral counts between 100,000 and 500,000 copies/mL attained undetectable viral loads using the 50-copies/mL assay. Similarly, 94% of the 48 patients assigned to atazanavir and 90% of the 31 patients assigned to lopinavir who had baseline CD4-positive cell counts of <50 cells/mm3 were able to achieve viral suppression to <50 copies/mL, based on an on-treatment analysis. The study was funded by Bristol-Myers Squibb Company. [Presentation title: Efficacy and Safety of Atazanavir/r vs Lopinavir/r in Treatment-Naïve Patients With Advanced Disease: CASTLE Study 96-Week Results. Abstract MOPEB041]
|
