3 Rs: reduction and replacement

The FDA announced new guidelines for drug testing today.

"Concerned about a system in which more than nine out of 10 experimental drugs fail when tested in humans, the Food and Drug Administration issued suggestions Thursday on how researchers can more efficiently evaluate the promise of new laboratory discoveries.

The vast majority of drug candidates fail once they're tested on humans, invariably for safety or efficacy reasons difficult to predict based on initial experiments done in test tubes and on animals. That can waste significant amounts of time and money, slowing the process of developing new drugs."

There are provisions for reducing the amount of animal testing done before human testing can begin and for an expanded roll for earlier invetigational trials in small groups of human subjects. One such approach is microdosing, where people are given very small doeses of a drug to study how the human body deals with the chemicals.