FDA Sought Metallosis Data Before DePuy ASR Hip Recall: Report

Weeks before Johnson & Johnson began phasing its DePuy ASR metal-on-metal hip implants from the market, allegedly due to falling sales, federal investigators sent a letter expressing concern about reports of metallosis from the hip replacement and high failure rates reported among individuals who received the device. 

According to a report by the New York Times, the FDA sent a letter to DePuy Orthopaedics in August 2009 rejecting the DePuy ASR hip resurfacing system for sale in the United States. However, that rejection letter also expressed concerns about all variations of the DePuy ASR, including a metal-on-metal hip replacement system that was approved for sale in the U.S.

The following month, after receiving the letter, Johnson & Johnson’s DePuy Orthopaedics subsidiary started to phase out the ASR line, while trying to quickly sell remaining stock and convince doctors to begin using other DePuy products. At that time, the manufacturer denied that there were any safety concerns with the hip, and suggested that the product was being phased out because of declining sales.

One year after the letter, the a worldwide DePuy ASR hip recall was issued for more than 93,000 of the devices sold. At that time, Johnson and Johnson acknowledged that the DePuy ASR was associated with a higher-than-expected failure rate, which estimated suggested may cause one out of eight people to experience problems within five years.

The FDA letter questioned much of the data DePuy used to promote its ASR hip implants as safe, noting that “there appear to be some publicly available data on the ASR that suggest somewhat poorer results for the device than results suggested by the data which you submitted.”

At the time, national hip implant registries from the U.K. and Australia were raising concerns about high failure rates and a high rate of revision surgeries by DePuy ASR hip recipients who had to have the implants removed or replaced due to complications and catastrophic failures.

The letter also raised questions about high levels of metal ion in patients’ blood which was indicated in DePuy’s own data long before a recall was issued. “You have provided several abstracts with selected blood metal ion analyses from patients implanted with the ASR Hip System,” the FDA letter states. “The high concentration of metal ions observed in some of these patients is concerning.”

DePuy maintains that its decision to phase out the hip implants almost a year before the recall was purely a marketing decision, and characterizes the FDA letter as not one of concern or proof that there was a problem, but as a letter seeking more data. The company claims that its own data did not reveal a high rate of failures until much later, after which it quickly issued the recall.

Like many metal-on-metal hip implants, the DePuy ASR line contained chromium and cobalt in its ball-and-socket design. In recent years there has been more and more data indicating that these devices shed metal particles into the body, causing metal hip blood poisoning, also known as metallosis. Metallosis has been linked to tissue damage, tumors and may increase the risk of cancer, according to some research.

In May 2011, the FDA asked device manufacturers to obtain more information about the level at which the metal particles shed by hip replacements becomes dangerous, how much metal they actually shed and what the potential side effects of metallosis are.

On February 28, Britain’s health agency, the Medicines and Healthcare Products Regulatory Agency (MHRA) issued new guidance stating that patients who have received large-head metal hip implants should have blood tests to check for metallosis every year for the rest of their lives.

The recommendation could affect about 50,000 metal-on-metal hip implant recipients in Britain, and hundreds of thousands of people in the rest of the world if that advice were followed by all metal hip patients.

Approximately 3,500 individuals throughout the U.S. have already filed a DePuy ASR hip lawsuit against Johnson & Johnson and DePuy, alleging that the company failed to adequately research the design of their implant or warn about the risk of metal-on-metal hip poisoning.

Similar product liability lawsuits have also been filed over other metal-on-metal hip replacements, such as the DePuy Pinnacle, Wright Conserve Cup, Biomet M2A-Magnum and others.