FDA has approved Allergan’s Natrelle 410 Highly Cohesive Anatomically Shaped Silicone-Gel Filled Breast Implant to increase breast size (augmentation) in women at least 22 years old and to rebuild breast tissue (reconstruction) in women of any age.

FDA based its approval on seven years of data from 941 women. According to the agency, most complications and outcomes reflect those found in previous breast implant studies including tightening of the area around the implant (capsular contracture), re-operation, implant removal, an uneven appearance (asymmetry), and infection. In addition, investigators observed fissures (cracks) in the gel of some Natrelle 410 implants. This is a characteristic called gel fracture and is unique to this implant.

“It’s important to remember that breast implants are not lifetime devices. Women should fully understand the risks associated with breast implants before considering augmentation or reconstruction surgery, and they should recognize that long-term monitoring is essential,” says Jeffrey Shuren, MD, director of the FDA’s CDRH.

“The data we reviewed showed a reasonable assurance of safety and effectiveness,” says Shuren. “We will be looking at the results from post-approval studies that will focus on their long-term safety and effectiveness.”

The silicone gel in the Natrelle 410 implant contains more cross-linking compared with the silicone gel used in Allergan’s previously approved Natrelle implant. This increased cross-linking results in a silicone gel that’s firmer. Cross-linking refers to the bonds that link one silicone chain to another. The clinical significance of this type of silicone gel is not known.

Allergan’s studies did not compare the safety and effectiveness of the Natrelle 410 implant to other previously approved silicone gel-filled breast implants on the market. Therefore, these implants cannot be directly compared with any previously FDA-approved implant, FDA says.

FDA requires that Allergan conduct a series of post-approval studies to assess long-term safety and effectiveness outcomes and the risks of rare disease. Lessons learned from previous post-approval studies on silicone gel-filled breast implants informed the design of post-approval studies for the Natrelle 410.

As a condition of approval for the Natrelle 410 breast implants, Allergan must:

• Continue to follow, for an additional five years, approximately 3,500 women who received the Natrelle 410 implants as part of the company’s continued access study.
• Conduct a 10-year study of more than 2,000 women receiving Natrelle 410 silicone gel-filled implants post-approval to collect information on long-term local complications (e.g., capsular contracture, reoperation, removal of implant, implant rupture) and less common potential disease outcomes (e.g., rheumatoid arthritis, breast and lung cancer, reproductive complications).
• Conduct five case control studies to evaluate the possible association between the Natrelle 410 implants, as well as other silicone gel-filled breast implants, and five rare diseases—rare connective tissue disease, neurological disease, brain cancer, cervical/vulvar cancer and lymphoma.
• Evaluate women’s perceptions of the patient labeling.
• Analyze the Natrelle 410 implants that are removed from patients and returned to the manufacturer.

With this approval, FDA says that there are now four FDA-approved silicone gel-filled breast implant products available in the US manufactured by three companies: Allergan, Mentor, and Sientra.