In another example, the authors point to the FDA's 2008 approval of a microarray kit used to compare RNA in a tumor of unknown origin with 15 common tumor types as a way of diagnosing cancer. That kit was approved with a "predicate" of a type of support software that was approved in 2005, that helps diagnose autoimmune disorders. The software was determined to be substantially equivalent to a drug profiling system, cleared in 1995, that tests for illicit drugs.
"Thus, a screening test for illicit drugs ultimately allowed for the clearance of a malignancy diagnostic test, simply because both use computer programs to compare samples to an existing database," the authors wrote.
In another example, the authors criticized the FDA's approval of a transcranial magnetic stimulation device intended to treat depression. The FDA allowed TMS to use electroconvulsive therapy as a predicate "even though ECT involves the administration of electrical currents to induce a generalized seizure."
"Despite this claim of equivalence, the manufacturer, Neuronetics, provided no information suggesting it conducted any studies directly comparing the two devices; instead, it conducted a nine-week RCT (randomized clinical trial) comparing TMS to a placebo."
In another example, the authors found problems in the FDA's approval of a vagus nerve stimulator, a surgically implanted device for treating depression that the authors said did not demonstrate a statistically significant benefit after 10 weeks.
But the manufacturer seeking approval relied on follow-up data at one-year "in which treated patients were claimed to have improved more than a non-randomized, unblinded, non-concurrent control group." Also, both of the groups were permitted co-interventions.
The article quoted a psychopharmacology expert in the FDA's drug center who advised that, with similar data for an antidepressant drug, the Center for Devices and Radiological Health (CDRH) would not have permitted the filing of a new drug application. "It is artificial for us to consider one study for a device (that is negative on face) as sufficient to provide evidence for regulatory efficacy when we require positive studies for a drug."
An FDA spokesman Wednesday responded to the article saying the agency will take Public Citizen's recommendations "under consideration as we continue to address many of the issues raised.
"Specifically, we are in the process of conducting an internal review of our 510(k) clearance program to improve our decision making and better support our mission to protect and promote public health. In addition, the Institute of Medicine is in the midst of its review (expected next year) of the same program to determine changes that could help us better achieve our goals."
The spokesman added that the FDA last year began reviewing safety and effectiveness information on the 25 medical device types that are considered Class III, (devices that are considered novel, with the highest risk). The agency is awaiting regulations that will either require manufacturers to submit premarket approval applications or re-classify the devices into lower risk categories, Class I or Class II.
"Both of these efforts are part of a broader set of initiatives published as CDRH's 2010 Strategic Priorities, which outlines the areas we think present significant opportunities to improve our effectiveness. These priorities are accompanied by timeframes so that CDRH can operate with transparency and the public can monitor our progress."