Menaflex Collagen Scaffold, a knee repair device manufactured by ReGen Biologics, "should not have been cleared for marketing in the United States," the Food and Drug Administration has announced after reevaluating its December 2008 decision to clear the device.

The agency says it will now begin the process to rescind its marketing clearance for Menaflex, a move that would prohibit ReGen from selling it in the United States until the FDA approves a new marketing application or grants a classification petition for it.

The decision comes after a September 2009 FDA report that identified problems with the agency's original evaluation of Menaflex and suggested that its clearance was influenced by "extreme" pressure from federal lawmakers. The report spurred the FDA to appoint a team of scientists who were not involved in the previous review of the device to reevaluate the scientific evidence.

"The FDA has now concluded that the Menaflex device is intended to be used for different purposes and is technologically dissimilar from devices already on the market, called 'predicate devices,'" the agency announced last week. Predicate devices repair or reinforce damaged tissue, whereas the Menaflex Collagen Scaffold stimulates "the growth of new tissue to replace tissue that was surgically removed," explains the FDA. "Because of these differences, Menaflex should not have been cleared."

The FDA says that in general it won't be necessary or appropriate to explant the device. Instead, patients who received the Menaflex implant should talk to their physicians about what, if any, steps should be taken. Meanwhile, the device will remain on the market until the FDA officially rescinds its clearance or ReGen voluntarily withdraws its marketing clearance.

Irene Tsikitas

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