In late 2002, Chiron Corporation announced its decision to shut down a large pivotal study of the drug, interleukin-2 (IL-2, Proleukin). In the days and weeks following the announcement, researchers and community activists met with the company to negotiate for the SILCAAT study to continue. In February 2003, heroic efforts by non-Chiron scientists to continue this important study were successful, and a transition of the study from Chiron into independent hands was completed. The study will continue.
For the nearly 2,000 volunteers in SILCAAT, there have been a few changes in how the study is conducted. Some minor changes have been made in the study.
What's perhaps most important to note is that Chiron's decision to stop SILCAAT was not a scientific decision, but rather a business decision. Typically decisions about stopping a study happen because the study is unable to answer the scientific question it set out to answer or because one of the study groups is doing markedly better or worse than the other(s). To the contrary in this instance, the study is in midstride and progressing toward answering the question in the expected timeframe. It's extremely unusual for a company to stop when everything is proceeding as planned and expected.
This certainly doesn't make Chiron any great hero. Their business decision to pull support from this study is an affront to people living with HIV at best, and morally corrupt at worst. In facing perhaps the greatest plague in human history, Chiron leadership turned its back. Particular kudos goes to Dr. Jim Neaton at the University of Minnesota and Dr. Cliff Lane at the National Institutes of Health for their leadership in ensuring that SILCAAT continues.