Stung by a series of drug safety scandals, the Food and Drug Administration now taking more time to review new drug applications, according to the New York Times.

The newspaper reported on August 5th that for drugs approved in the first half of 2005, the average time from application to approval was 29 months, compared with an average of 16 months for drugs approved in the first half of 2004.

This would suggest that Sanofi-Aventis, which in June said it had not been granted a priority review by the FDA for its new obesity drug Acomplia (rimonapant), may well be disappointed in its hopes to begin marketing the drug in the United States in 2006.

The FDA's more conservative approach would appear linked to two highly publicized drug problems this last year -- one involving antidepressants and suicide risk, and the other the pain pill Vioxx, which was withdrawn from the market after it was found to increase the risk of heart attacks and strokes.

These episodes resulted in heavy criticism from Congress that the FDA had failed to protect the public against drug dangers.

Dr. Scott Gottlieb, deputy FDA commissioner, told the New York Times that the agency's advisory committees -- crucial arbiters of drug risks -- are vulnerable to a growing chorus of such criticism. If the advisory committees become more cautious, he said, the FDA might follow their lead.

Despite Sanofi's contention that results of their study of the safety and tolerability of Acomplia in four major clinical trials showed that side effects were mainly mild and transient, the drug is expected to come under close scrutiny because it is the first in a new class of medicines that acts on a receptor in the brain.

The FDA's growing caution is seen by many observers as an understandable reaction to the criticism it has received, and observers are predicting that the approval process is likely to move more slowly for some time.