Narrator: This is Science Today. There's a new type of AIDS drug on the market, called protease inhibitors, that have been receiving a lot of attention lately.

Kahn: They have been used for short periods of time, whether or not they will ever be able to eradicate virus in combination with other drugs is unclear, but they have developed a hype about them that the AIDS epidemic is over. It clearly is not.

Narrator: Dr. Jim Kahn of the University of California, San Francisco says it's too early to tell how effective they'll be over the long run, but there's no denying they have the potential to prolong life.

Kahn: They reduce disease progression, they reduce virus, they help increase T cells, they are a breakthrough in the treatment of HIV infected people.

Narrator: On the downside, protease inhibitors have severe side effects. Plus, people who take them have to be incredibly disciplined about it -- they literally can't afford to miss one dose.

Kahn: Because if you don't take enough of the medicine you won't get high enough blood levels, and if you don't get high enough blood levels the virus will replicate and will become resistant.

Narrator: For Science Today, I'm Steve Tokar.