A surgical mesh company claims the FDA improperly called one of its products’ safety into question.

The agency said last week that two surgical mesh brands used off-label in breast reconstruction surgery have had “significantly higher major complication rates.”

It named FlexHD by MTF Biologics and AlloMax by BD as having had higher rates of explantation, reoperations and infections two years after surgery when compared with patients who received one of two other brands of surgical mesh or no mesh. The mesh type in question is an acellular dermal matrix (ADM) made of human or animal skin from which the cells are removed and the support structure is left in place.

MTF Biologics has not provided FlexHD for breast reconstruction for many years, Heather Brennan, VP & GM of plastic and reconstructive surgery, said in an email to Medical Design & Outsourcing.

“In 2013, MTF developed FlexHD PLIABLE, which underwent significant design changes from FlexHD and is routinely screened for endotoxin,” Brennan said. “It is this tissue form, made available by MTF, that surgeons primarily use for breast reconstruction. The vast majority of the data the FDA reviewed did not relate to FlexHD PLIABLE. The FDA reviewed old FlexHD data from the Mastectomy Reconstruction Outcomes Consortium (MROC) study for which the brand comparative data is not peer-reviewed nor published. The FDA also referenced three studies as support for a potentially higher rate of complications. Again, these studies primarily reviewed old FlexHD data, not the current product, FlexHD PLIABLE.”

The FDA omitted from its analysis five additional peer-reviewed, published studies reviewing data from the old FlexHD product that pointed to its equivalence to or superiority over AlloDerm, according to Brennan. “Additionally, since FlexHD PLIABLE has been on the market for several years, there are also two comparative studies evaluating FlexHD PLIABLE and AlloDerm RTU, which found no significant difference in complications rates between the two ADMs. These are also missing from FDA’s review,” she said.

In its safety advisory, the FDA said it has cleared some ADMs for use in certain types of surgeries, such as hernia repair, to reinforce tissue where weakness exists. The agency has not cleared any ADM for use in post-mastectomy breast reconstruction but said some surgeons have been using it off-label for years.

“We are deeply disappointed and concerned that the FDA’s incomplete and partial data review will cause unfounded fear and concern in the thousands of patients we have served over the years,” Brennan wrote. “Based on all current and relevant published data, MTF has every confidence in the safety of our tissues used in breast reconstruction. We look forward to the opportunity to present the additional data to the FDA for an evidence-based, well-balanced review.”

BD told MDO last week that it “does not currently promote the use of AlloMax Surgical Graft in breast procedures, nor is it included in the product’s instructions for use.”

In a statement emailed on Wednesday to MDO, an FDA spokesperson said the agency stands by its analysis and safety communication.

“The purpose of the safety communication is to inform patients and health care providers that certain acellular dermal matrix (ADM) products used in implant-based breast reconstruction may have a higher chance for complications or problems, based on the analysis of the MROC study and published literature,” the spokesperson said. “It is also designed to encourage patients to discuss all of the possible benefits and risks related to breast construction procedures with their health care provider. Please note that although ADM is used for other types of reconstruction, the FDA has not cleared or approved ADM for use in breast reconstruction. The safety communication discusses the limitations of the study and the FDA’s analysis and highlights the need for additional clinical data.”

The agency “will continue to monitor the latest scientific literature, as well as reports of adverse events related to ADM use to help us understand the risks and keep the public apprised of any important new data,” added Binita Ashar, director of CDRH’s Office of Surgical and Infection Control Devices.

This report has been updated with comments from the FDA.