Debiopharm presents new data confirming anti-HCV activity of cyclophilin inhibitor for Debio-025

Shows HCV mean viral load decrease of 3.6 Log10 in HIV/HCV co-infected patients

LAUSANNE, Switzerland, October 31, 2006 – The Debiopharm Group (Debiopharm), a global independent biopharmaceutical development company specialising in oncology and serious medical conditions, today presented results from a phase Ib study of cyclophilin inhibitor Debio-025, in treatment-naïve HIV/HCV (hepatitis C virus) co-infected patients. The aim of the study was to determine the anti-viral effect, pharmacokinetic profile and safety of an oral therapy with Debio-025. The data, presented at the American Association for the Study of Liver Diseases (AASLD) conference, confirm the anti-viral effect of Debio-025 in HIV/HCV co-infected subjects.

The 15 day double blind, placebo controlled study, with twice daily oral doses of Debio-025 shows that the product was rapidly absorbed, with peak plasma levels reached after two hours and a terminal half life of 100 hours. The mean maximal decrease in HCV viral load in Debio-025 treated patients was 3.6 log10, a highly significant difference with placebo. In 15 out of 16 subjects treated with Debio-025, HCV viral load decreased by more than 2 log10, which means a decrease of more than 99% of the viral load. In three patients the virus even became undetectable after 8 or 15 days. All three HCV genotypes (1, 3 and 4) identified in the study, responded well to the dose administered and no patient developed a viral breakthrough during the treatment.

“We believe Debio-025 to be a very promising novel compound with a unique mode of action. Having shown such an important anti-viral activity against HCV in the difficult to treat subpopulation of HIV/HCV co-infected patients is a major achievement. We are therefore very optimistic about the future potential of this drug in the larger population of HCV infected patients,” said Robert Flisiak, Professor at the Medical University of Bialystok, Poland and lead investigator of the study.

About HCV
HCV is the most prevalent liver disease in the world and is considered by the World Health Organization as an epidemic. Because HCV can infect a patient for decades before being discovered, it is often called the “silent” epidemic. Studies suggest that over 200 million people worldwide are infected with HCV, an overall incidence of around 3.3% of the world’s population. In the US alone, nearly 4 million people are or have been infected with HCV and of these, 2.7 million have an ongoing chronic infection, the majority being between 40 to 60 years old. A fourfold increase in the number of adults diagnosed with chronic HCV infection is projected from 1990 to 2015, since most persons with chronic HCV infection have yet to be diagnosed but are likely to come to medical attention in the next decade.

About Debio-025
Debio-025 is a synthetic first-in-class cyclophilin inhibitor, being tested in humans as a potential anti-HCV drug. Debio-025 binds strongly to cyclophilins, host cell proteins thought to confer a replication advantage to HCV. Its potent inhibitory activity on the HCV replication was shown in preclinical studies.

About The Debiopharm Group
The Debiopharm Group is a global biopharmaceutical development company that in-licenses promising biologics and small molecule drug candidates. Debiopharm develops its products for global registration and maximum commercial potential for out-licensing to pharmaceutical partners for sales and marketing.

Debiopharm independently funds the worldwide development of all of its products while providing expertise in pre-clinical and clinical trials, manufacturing, drug delivery and formulation, and regulatory affairs.

Founded in 1979 and headquartered in Lausanne, Switzerland, Debiopharm has developed three products with global combined sales in excess of $2.3 billion in 2005.
For more information on the Debiopharm Group, please visit: www.debiopharm.com