FDA Inquiry Leads to Hip Implant Phaseout

In continuing with recent trends, bad news continues to surface on behalf of the recent transgressions committed by the Johnson & Johnson (J&J) subsidiary DePuy. According to administrative and corporate records, 2009 witnessed J&J executives initiate a phase out plan that would relinquish their remaining inventories of Articular Surface Replacement (ASR) Hip Systems. However, motion to sell off their inventories conveniently came just weeks after the U.S. Food and Drug Administration (FDA) sent a letter to DePuy requesting additional safety data pertaining to ASR devices.

Metal-on-metal hip replacement systems, such as the ASR brought to us by DePuy, are made up of a series of metallic components (cobalt and chromium) in order to promote longevity and dexterity. As their name suggests, they are used to replace the hips of patients who have begun to develop a significant loss of functionality while simultaneously experiencing severe pain. However, recent studies have suggested that DePuy’s ASR device may coincide with catastrophic failure rates and severe complications. Of particular concern is a distinct concentration of metal ions discovered in the blood of patients who have already received the device. According to an FDA letter, the agency found the high concentration of metal debris, “concerning.”

Further complicating the already ambiguous situation, were reports from other countries where the implant was then being used. According to these reports, the ASR hip system was performing “somewhat more poorly” than data submitted by the company’s DePuy Orthopaedics unit indicated. By mid-2009, for example, data from Australia showed that the device was failing at high rates just a few years after implantation, rather than lasting 15 years as expected.

Following reports of unacceptable failure rates and the presence of dangerous metal ions in the blood of patients, the FDA decided to interject. The FDA’s opinions were contained in a so-called nonapprovable letter in which the agency confidentially notified DePuy in 2009 that it was turning down the company’s application to sell the device in the United States. Subsequently, this was the same letter requesting additional safety data. However, upon receiving this notice, DePuy did not recall the ASR Hip Systems. Instead, just weeks after receiving the letter, DePuy began to sell the devices for patient use in both the U.S. and abroad.

While it remains unknown as to how many patients received the ASR device, it is estimated that approximately 93,000 patients received the model worldwide. In addition to dealing with an extremely high rate of premature failure, an influx of patients suffered from what doctors are referring to as metallosis. This condition is the direct result of metal pieces wearing against each other to the point that they create metal debris that collects in the surrounding tissue. Metallosis witnesses the leeching of hazardous metal shards into the fluid of surrounding tissue. The resulting damage may lead to severe pain and even the death of localized tissue.

“We are almost out of ASR, and the few doctors still using ASR are threatening to leave DePuy anyhow,” a company executive wrote in an e-mail nine months after receiving the FDA’s initial letter. Subsequently, this e-mail, and many more like it, are being used in thousands of pending defective hip replacement lawsuits against DePuy.

Contrary to public opinion, and that of healthcare providers across the country, DePuy executives have insisted that they acted appropriately in recalling the implant model when they did. Officials acknowledged that prior to August 2010, the ASR devices were preforming as well as competing implants. They have also repeatedly said that their decision to phase out the ASR devices was based on slowing product sales, rather than any factors related to the previously mentioned FDA letter.

A DePuy spokeswoman, Mindy Tinsley, said the only conclusion the administration reached in its letter was that the data submitted by DePuy “was inadequate to evaluate the safety and effectiveness” of the device.