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Lack of publicly available scientific evidence on the safety and effectiveness of implanted medical devices.

IMPORTANCE
Under the 510(k) process, the US Food and Drug Administration (FDA) clears about 400 implanted medical devices that are considered moderate to high risk for market each year without requiring clinical testing. Instead, the FDA requires the applicant to provide scientific evidence that the new device is "substantially equivalent" to a device or devices already on the market (predicate devices). Companies are legally required to submit the evidence to the FDA and to make publicly available at least a summary of the evidence.


OBJECTIVE
To assess the types of scientific evidence used to determine substantial equivalence, safety, or effectiveness for a representative sample of implanted medical devices; the number of predicates for each implant; and whether this evidence was publicly available.


DESIGN
Using FDA databases, we determined the device categories of the first 5 implanted medical devices cleared through the 510(k) process in 2008: cardiovascular, dental, general and plastic surgery, neurological, and orthopedic. We then identified the first 2 implanted medical devices approved in each of the 5 categories for each year from 2008 through 2012. The sample of 50 devices included, for example, total hip implants, vascular embolization devices, and surgical mesh. We also identified the 1105 predicates the manufacturers listed for these devices.


MAIN OUTCOMES AND MEASURES
For each implanted medical device and its predicates, we determined whether clinical or nonclinical scientific evidence was provided to the FDA to support the claim of substantial equivalence and whether this evidence was publicly available. We also determined if safety or effectiveness data were provided.


RESULTS
Scientific data to support the claim of substantial equivalence were publicly available for 8 of the 50 newly cleared implants (16%) and 31 of their 1105 listed predicates (3%). Most of the evidence was nonclinical data; some of the data also evaluated safety or effectiveness.


CONCLUSIONS AND RELEVANCE
Despite the legal requirement that scientific evidence of substantial equivalence be publicly available for medical devices cleared by the FDA through the 501(k) process, such information is lacking for most implanted medical devices cleared between 2008 and 2012, as well as for their predicates.