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Valeant Pharmaceuticals Highlights Taribavirin Phase IIb End of Study Data Presentation at American Association for the Study of Liver Disease (AASLD) Annual Meeting

ALISO VIEJO, Calif., Nov. 3 /PRNewswire-FirstCall/ -- Valeant Pharmaceuticals (NYSE: VRX) today announced that results from the week-72 analysis for its Phase IIb dose-finding clinical trial for taribavirin, a prodrug of ribavirin which is in development for the treatment of chronic hepatitis C in conjunction with a pegylated interferon, were presented at the American Association for the Study of Liver Disease (AASLD) 60th Annual Meeting in Boston. It is believed that taribavirin (TBV) may present an alternative therapy to ribavirin (RBV) for the treatment of hepatitis C by delivering similar efficacy to ribavirin but with significantly less anemia, which is the main treatment-limiting toxicity associated with ribavirin.


The results were presented in an abstract entitled "Sustained Virologic Response Results for Weight-Based Taribavirin Versus Weight-Based Ribavirin, in Naïve Chronic Hepatitis C, Genotype 1 Patients", with an oral presentation given by Fred Poordad, M.D., Chief of Hepatology at the Center for Liver Disease and Transplant, Cedars-Sinai Medical Center, Los Angeles, CA and principal investigator in this study.


"The final results of this Phase IIb study are promising, and imply that comparable efficacy can be achieved when compared to ribavirin," said Dr. Poordad. "As is known for ribavirin, low doses are associated with a high relapse rate and, except for the lowest dose with taribavirin, relapse rates are also comparable to ribavirin. The safety of this ribavirin analog is of particular relevance in that its use is associated with significantly less anemia in an evolving era of small molecule therapies, where anemia appears to be more problematic."


The company has previously reported results from this Phase IIb trial exploring weight- based dosing of taribavirin at 20, 25 and 30mg/kg vs. weight-base dosed ribavirin 800-1400mg. The study consisted of 48 weeks of treatment with a 24-week post-treatment follow-up period. Consistent with previous reports, the viral response data continued to show comparable reductions in viral load for weight-based doses of taribavirin and ribavirin in a difficult-to-treat population of subjects infected with hepatitis C genotype 1 and end-of-study sustained virologic response rates were again comparable across the treatment groups. Relapse rates were identical for taribavirin 25mg/kg and weight-based doses of ribavirin. Importantly, the statistically significantly lower anemia rate for patients receiving taribavirin in the 20mg/kg and 25mg/kg arms versus the ribavirin control arm has been maintained at a rate similar to the end-of- treatment (week 48) throughout.


Table: Efficacy/Safety (intent-to-treat)

                                        Phase IIb
                          TBV            TBV           TBV          RBV
                        20 mg/kg       25 mg/kg      30 mg/kg    800-1400mg
                          n=67           n=70          n=68         n=70
    Undetectable(1)    11 (16.4%)     10 (14.3%)     11 (16.2%)     8 (11.4%)
    Undetectable(1)    28 (41.8%)     29 (41.4%)     17 (25.0%)    22 (31.4%)
    Undetectable(1)    30 (44.8%)     27 (38.6%)     23 (33.8%)    26 (37.1%)
    Undetectable(1)    19 (28.4%)     19 (27.1%)     19 (27.9%)    19 (27.1%)
    Relapse Rate       10 (34.5%)      5 (20.8%)      3 (13.6%)     5 (20.8%)
    Anemia 48
    weeks(2)            9 (13.4%)*    11 (15.7%)*    19 (27.9%)    23 (32.9%)

    (1) HCV RNA < 39 IU/mL
    (2) Anemia: hemoglobin < 10g/dL
    *P<0.05 vs. RBV


The most common adverse events during treatment were fatigue, nausea, flu-like symptoms, diarrhea, and insomnia. The incidence rates for these adverse events among treatment arms were generally comparable except with respect to diarrhea, where incidence of diarrhea was approximately twice as common in patients receiving taribavirin compared to patients receiving ribavirin. However, the diarrhea was generally mild and not treatment limiting for taribavirin or ribavirin patients.


The Phase IIb trial was a U.S. multi-center, randomized, parallel, open-label study in 278 treatment-naive, genotype 1 patients evaluating taribavirin at weight-based doses of 20 mg/kg, 25 mg/kg, and 30 mg/kg per day in combination with pegylated interferon alfa-2b. The control group was administered weight-based dose ribavirin (800/1000/1200/1400mg daily) and pegylated interferon alfa-2b. Overall treatment duration was 48 weeks with a post-treatment follow-up period of 24 weeks.


About Taribavirin

Taribavirin is an investigational compound that has not been found by the Food and Drug Administration (FDA) or any other regulatory agency to be safe or effective in the diagnosis, mitigation, treatment or cure of any disease or illness. It may not be sold or promoted in the United States unless and until approved for marketing by the FDA. Similar restrictions apply in other countries.


About Study 204

In the Phase IIb study (previously disclosed as Study 204), 278 treatment naïve, genotype 1 patients were randomized with the following patient demographics: mean age 48.8 yr, 61.1% male, 30% African-American or Latino, 80.7% viral load >=400,000 IU/mL and 82.1 kg mean weight. Week 72 efficacy and safety results for the intention-to-treat (ITT) population are shown in the table above.


About Valeant

Valeant Pharmaceuticals International (NYSE: VRX) is a multinational specialty pharmaceutical company that develops, manufactures and markets a broad range of pharmaceutical products primarily in the areas of neurology and dermatology.



This press release may contain forward-looking statements, including, but not limited to, statements regarding the potential for taribavirin in the treatment of hepatitis C, and the continuing role of ribavirin or taribavirin in the treatment of hepatitis C, Forward-looking statements may be identified by the use of the words "anticipates," "expects," "intends," "plans," "should," "could," "would," "may," "will," "believes," "estimates," "potential," or "continue" and variations or similar expressions. These statements are based upon the current expectations and beliefs of management and are subject to certain risks and uncertainties that could cause actual results to differ materially from those described in the forward-looking statements. These risks and uncertainties include, but are not limited to, risks and uncertainties discussed in the company's most recent annual or quarterly report filed with the U.S. Securities and Exchange Commission, which factors are incorporated herein by reference. Readers are cautioned not to place undue reliance on any of these forward-looking statements. Valeant undertakes no obligation to update any of these forward-looking statements to reflect events or circumstances after the date of this press release or to reflect actual outcomes.



    Laurie W. Little, Valeant Pharmaceuticals



SOURCE Valeant Pharmaceuticals International

Laurie W. Little of Valeant Pharmaceuticals, +1-949-461-6002,

Posted: November 2009