Company Backs Out of Immune Drug Study

The Chiron Corporation, manufacturer of the drug interleukin-2 (commonly called IL-2), has announced that it is pulling out of a large study of that drug called SILCAAT.

About SILCAAT

In this study, some HIV positive volunteers received standard therapy with highly active antiretroviral therapy (HAART) while others received a combination of HAART and injections of IL-2. The reason IL-2 is being tested is that regular injections of this drug can raise levels of important immune cells called CD4+ cells. When levels of these key cells fall, HIV positive people can develop life-threatening complications. People with HIV/AIDS who respond to HAART usually develop high levels of these cells. As a result, their risk of developing AIDS-related illnesses is greatly reduced.

The purpose of SILCAAT was to assess and compare the effects of a combination of IL-2 and HAART against that of HAART alone on the health of volunteers. Because HAART has already reduced death rates from AIDS, SILCAAT would have needed up to seven years and least 2,000 volunteers before enough data could have been collected to properly assess the impact of IL-2. Such large and lengthy trials are expensive and this is a major factor in Chiron's decision to discontinue funding. The company has also recently discontinued several other, non-HIV-related research projects.

What's Next?

Chiron is currently discussing what to do next with the researchers on SILCAAT's scientific committee. The researchers, led by professor Yves Levy in Paris, as well as his colleagues in Australia, Canada, the European Union and the United States, are interested in keeping the study running.

Another international trial of IL-2 called ESPRIT, with some Canadian volunteers, will continue, as this trial is funded by the National Institutes of Health.

For further information about SILCAAT in Canada call 1.800.CHIRON8 (244- 7668) or in the U.S. call 1.866.874.3153 and follow the voice prompts.

Reference

1. www.chiron.com/investor/news/release2.htm