Chiron Corporation announced a new collaboration agreement with CSL Limited, an Australian-based pharmaceutical company, to develop a therapeutic hepatitis C vaccine. Under the terms of the joint development agreement, Chiron will provide its novel hepatitis C virus (HCV) antigens, and CSL will contribute its proprietary Iscomatrix adjuvant technology.

"While there remains much development work ahead, the Phase I clinical trial, completed in collaboration with CSL, showed that our vaccine has a good safety profile and generates the type of immune responses required for a potential treatment for HCV," said John Lambert, president, Chiron Vaccines. "In the next year, we will build on this foundation, and indeed the foundation Chiron scientists laid with the identification of the hepatitis C virus in 1987, by testing the vaccine in chronically infected patients."

"This agreement further validates CSL's proprietary Iscomatrix adjuvant technology, and we are proud to use it to collaborate with our colleagues at Chiron Vaccines on developing a potential product for treating hepatitis C," said Brian McNamee, CEO of CSL Limited. "Hepatitis C infection remains a major health issue, and there is a clear need for improved therapy."

In 1987, Chiron scientists Michael Houghton, Qui-Lim Choo, and George Kuo, cloned and first identified HCV as the cause of transfusion-related non-A, non-B hepatitis. This breakthrough marked the first time a virus was cloned before it had been grown in tissue culture or otherwise isolated. The Chiron scientists received the prestigious Lasker Award in recognition of this discovery. Since the initial work, Chiron has been granted more than 100 HCV-related patents in over 20 countries, including patents directed to hepatitis C polypeptides encoded throughout the genomes of HCV. Such polypeptides can be used in a variety of medical applications, including blood screening, clinical diagnosis, vaccines and as therapeutic targets for drug screening. A number of therapeutic companies have been granted nonexclusive licenses to Chiron's HCV technology for drug screening purposes, including Bristol-Myers Squibb, GlaxoSmithKline, Japan Tobacco Inc. and Pfizer.

The hepatitis C virus (HCV) is transmitted via blood or body fluids. Approximately 4 million Americans have been infected with HCV, of whom 2.7 million are chronically infected. Seventy per cent of those chronically infected develop chronic liver disease, making HCV infection the leading indication for liver transplantation. Treatment consists of interferon alone or in combination with ribavirin, with combination therapy ridding the virus in 50-80 per cent of cases, depending on the virus genotype. No vaccine exists to prevent HCV.