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FDA Approves Labeling Update for Reyataz (atazanavir sulfate) Capsules to Include 96-Week Data for Previously Untreated HIV-1 Infected Adult Patients

PRINCETON, N.J.--(BUSINESS WIRE)--Nov 5, 2009 - Bristol-Myers Squibb Company today announced that the U.S. Food and Drug Administration (FDA) has approved a labeling update for Reyataz to include long-term data from the CASTLE Study. The CASTLE Study assessed a once-daily Reyataz/ritonavir (Reyataz/r)-based regimen versus a twice-daily lopinavir/ritonavir (LPV/r)-based regimen in previously untreated adult patients infected with HIV-1. Data from the study demonstrate enduring virologic response through 96 weeks of treatment with Reyataz/r as part of combination therapy.

According to the most recent report from the Centers for Disease Control and Prevention, more than one million people are living with HIV and the annual incidence of new infections was 56,300 in the U.S.1 It is critical that effective and tolerable medicines are available to patients initiating antiretroviral therapy. Long-term data from the CASTLE Study demonstrate that treatment with Reyataz/r can effectively suppress HIV viral load over 96 weeks in treatment-naïve patients.

In the CASTLE Study, a majority of patients on the Reyataz/r regimen achieved undetectable viral load defined as HIV-1 RNA <50 copies/mL (Reyataz/r 75% vs. LPV/r 68%) – confirming efficacy through 96 weeks. Low rates of drug resistance were observed at 96 weeks in patients who failed the Reyataz/r regimen, with one patient developing genotypic/phenotypic resistance to Reyataz and five patients developing genotypic/phenotypic resistance to emtricitabine. In a pre-specified analysis, efficacy in patients with high baseline viral load (‰¥100,000 copies/mL) was demonstrated: 74% of 223 patients in the once-daily Reyataz/r arm achieved undetectable viral load at 96 weeks vs. 67% of 222 patients in the twice-daily LPV/r arm.

In addition, the 96-week data confirmed the effect of Reyataz on lipids. There were lower mean increases from baseline in total cholesterol, LDL cholesterol and triglycerides with Reyataz/r compared to LPV/r; the Reyataz/r arm was associated with the following mean increases from baseline: total cholesterol (13%), LDL cholesterol (14%), HDL cholesterol (21%), and triglycerides (13%). The LPV/r regimen was associated with the following mean increases in lipids: total cholesterol (25%), LDL cholesterol (17%), HDL cholesterol (29%), and triglycerides (50%).

Safety events at 96 weeks were consistent with the 48-week results in this study. Grade 2-4 treatment-related adverse events that occurred in 2% or greater of patients on the Reyataz (atazanavir sulfate)/r regimen, regardless of causality, included jaundice/scleral icterus (5% and 0%), nausea (4% and 8%), diarrhea (2% and 12%), and rash (3% and 2%) in the Reyataz/r and LPV/r arms, respectively. Grade 3–4 increases in total bilirubin occured in 44% of patients in the Reyataz/r arm and in less than 1% of patients on the LPV/r regimen.

About the CASTLE Study

The international, multi-center, open-label, non-inferiority, 96-week CASTLE Study randomized 883 treatment-naive adults infected with HIV-1. Four hundred and forty patients were randomized to receive Reyataz 300 mg and ritonavir 100 mg once daily and 443 patients were randomized to receive fixed-dose lopinavir 400 mg and ritonavir 100 mg twice daily. Each was given in combination with a once-daily, fixed-dose combination of tenofovir disoproxil fumarate 300 mg/emtricitabine 200 mg. All patients had a baseline viral load of greater than or equal to 5,000 copies/mL; there was no CD4+ cell count restriction for study entry. The primary endpoint for the study was the proportion of patients with viral load less than 50 copies/mL at 48 weeks with an intent-to-treat (ITT) analysis according to confirmed virologic response. Of the 440 patients in the Reyataz/r arm, 78% met the primary endpoint of achieving undetectable viral load at 48 weeks, compared with 76% of the 443 patients in the LPV/r arm.

About Reyataz

Reyataz is a protease inhibitor that has been studied in both treatment-naive and treatment-experienced HIV-1-infected patients and is administered once daily as part of combination HIV therapy. Since its approval in 2003 by the FDA, Reyataz has become the most prescribed protease inhibitor, a central drug class in HIV therapy. For more information, please visit

About Bristol-Myers Squibb

Bristol-Myers Squibb is a global biopharmaceutical company committed to discovering, developing and delivering innovative medicines that help patients prevail over serious diseases. For more information, please visit

Reyataz is a registered trademark of Bristol-Myers Squibb. Norvir is a registered trademark of Abbott Laboratories.


1. HIV/AIDS in the United States: CDC HIV/AIDS Facts; August 2009. Centers for Disease Control and Prevention website. Available at Accessed September 2009.

Contact: Bristol-Myers Squibb


Cristi Barnett, 609-252-6028



John Elicker, 609-252-4611

Posted: November 2009

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