FDA raises bar for silicone breast implant approval: new guidance issued: recommendation of advisory panel rejected, additional safety data requested.

The Food and Drug Administration has revised its guidelines for manufacturers seeking approval to market silicone gel breast implants, curbing the hopes of the California company that seemed closest to this goal.

The new FDA guidance requires more rigorous investigation of lingering questions about the safety of silicone implants, says Dr. David W. Feigal Jr., director of FDA's Center for Devices and Radiological Health.

"We want to make very clear to sponsors of breast implant products what we feel needs to be established in marketing applications ... so that they can establish that those products are safe and effective," he said in a press briefing. "Our goals in putting out this new guidance are to make the roadmap to approval as clear as possible."

Silicone implants have been banned in the United States since 1992 because of concerns that they may possibly be linked to serious health problems, although they have been available to post-mastectomy patients taking part in approved clinical trials.

Besides reports of implants rupturing and silicone gel migrating elsewhere in the body, there have been concerns that implants may be linked to autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and fibromyalgia.

But the criticisms have sparked much debate from manufacturers and other supporters who claim that the problems reported with silicone implants are no greater than those reported with the approved saline-filled implants that are currently on the market. And, a 1999 Institute of Medicine review found no evidence that silicone gel implants were causing serious disease.

Nevertheless, Dr. Feigal said that the FDA would like to see more data on the rupture rate of silicone implants, the consequences of rupture, and how physicians should manage patients with ruptures.