While the House considers the Emergency Response Employees Disease Protection Act, San Diego, Calif.-based Epimmune Inc. is pioneering a new approach to hepatitis C vaccine development.

So far, Epimmune's experiments have been limited to mice, but the company expects to begin human clinical trials in 2001 and hopes to have a product to combat hepatitis C in three or four years.

The proposed legislation is designed to provide funding for a study and demonstration projects regarding cases of hepatitis C among firefighters, paramedics and emts. (See Washington Report, page 22.)

Epimmune's method involves using epitopes, which are small fragments (peptides) from protein antigens that trigger an immune response.

"Epimmune has a unique process for identifying, from pathogens or cancerous cells, epitopes that can be used to create vaccines for a number of serious diseases that are not currently being addressed," said Alessandro D. Sette, Ph.D, Epimmune's vice president and chief scientific officer. "By combining select epitopes from the hepatitis C virus, we have designed a vaccine that will, in effect, 'train' the immune system to recognize multiple, conserved (nonmutating) regions of the virus and mount a strong cell-mediated attack."

Currently, there's no approved vaccine for the prevention or control of hepatitis C, a potentially fatal liver disease caused by a virus. The Centers for Disease Control estimate that 3.9 million Americans have been infected, and 2.7 million are chronically infected. Worldwide, the number is 170 million people, more than five times the number infected with hiv.