The process for obtaining U.S. Food and Drug Administration approval for new drugs and devices is highly complex. Over the past several years the American Association of Neurological Surgeons (AANS) and Congress of Neurological Surgeons have established a mechanism by which neurosurgery can be more involved in the approval process as new medical devices and technologies move into the healthcare marketplace. This article briefly outlines the device approval process and neurosurgery’s structure for interfacing with the FDA.
The FDA Office of Device Evaluation consists of six centers, two of which relate to neurosurgery. The Center for Devices and Radiological Health is responsible for evaluating neurosurgical devices and the Center for Biologics Evaluation and Research oversees biologics that are used by neurosurgeons.
The Medical Device Amendments of 1976 to the federal Food, Drug and Cosmetic Act established three classes for medical devices based on risk to the patient:
- Class I General Controls-Devices that present minimal potential for harm.
- Class II Special Controls-Need special labeling or postmarket surveillance to be considered safe. Most medical devices are in this class.
- Class III Premarket Approval-These devices sustain or support life, are implanted or present potential risk of injury. Approximately 10 percent of medical devices fall into this category.
There are three paths to approval by FDA:
Premarket Notification 510(k)-The manufacturer must demonstrate that the device is substantially equivalent to an existing device. If the device is substantially equivalent, it is placed in the same class as the equivalent device. Upon approval of a device as equivalent, the FDA will issue a letter of substantial equivalence, which authorizes the manufacturer to market the device.
Premarket Approval (PMA)-The PMA process is more involved and requires the submission of clinical data to support claims made for the device. Generally, these devices would be in Class III.
Exceptions-The FDA may give expedited approval of a device for use only in clinical trials if the device is deemed of humanitarian benefit. Clinical trials using unapproved medical devices on human subjects are performed under an Investigational Device Exemption.
To help manufacturers comply with the FDA requirements, FDA provides a number of documents online. For some devices, experts including those of physician specialty societies have developed guidance documents with their recommendations for product standards.
In addition, during the Premarket Approval process, the FDA uses expert panels to review applications for device approval. The meetings are held in public, announced in the Federal Register, and provide the opportunity for any interested parties to comment in person or in writing. The panel then votes to approve, disapprove, or approve with conditions. That information is merely a recommendation to the FDA, which may accept or reject the panel’s recommendation.
Currently three neurosurgeons sit on the Neurological Devices Panel: Fernando Diaz, MD, Christopher Loftus, MD, and Stephen Haines, MD. The panel meets several times each year to advise the FDA on premarket applications that involve neurological devices.
In addition to the Neurological Devices Panel, devices used by neurosurgeons sometimes fall within the purview of other panels. For example, devices used in the spine are considered by the Orthopedic and Rehabilitative Devices Panel. That panel does not include a neurosurgeon but often one of the neurosurgeons from the Neurological Devices panel will be sworn in as a temporary member during the panel’s consideration of a device used in the spine.
Once a device is approved and marketed, the FDA requires the manufacturer to comply with FDA Good Manufacturing Practices guidelines and Medical Device Reporting regulations. The former guidelines cover the design, package, labeling, and marketing of a device, while the latter include the requirement to report adverse events involving the device.
AANS/CNS Neurosurgical Devices Forum
Several years ago the AANS and CNS established a Neurosurgical Devices Forum to improve interaction between neurosurgery, neurosurgical device manufacturers, and the FDA. The neurosurgeons on the forum serve as a resource to AANS/CNS Washington Office staff in responding to requests for information from the FDA. One goal of the forum is to ensure that neurosurgery is appropriately represented when the FDA considers devices used by neurosurgeons, particularly when those devices are referred to review panels other than the neurological devices forum. In addition, the forum has worked with the FDA, industry, and other specialty societies in the development of guidance documents. For example, members of the group are currently working with the American Academy of Orthopaedic Surgeons to develop a guidance document for artificial spinal discs.
The Neurosurgical Devices Forum is chaired by Richard G. Fessler, MD, and co-chaired by Fernando Diaz, MD. The forum also includes representatives from the various AANS/CNS sections: Howard Riina, MD, (Cerebrovascular); Robert Heary, MD, and Joseph Alexander, MD (Disorders of the Spine and Peripheral Nerves); Geoffrey Manley, MD, and William Welch, MD (Neurotrauma and Critical Care); Richard Osenbach, MD (Pain); Mark R. Proctor, MD (Pediatric Neurological Surgery); Jaimie Henderson, MD, and Paul Francel, MD (Stereotactic and Functional Surgery); Jeffrey Weinberg, MD, and Andrew Sloan, MD (Tumors).
Catherine Jeakle Hill is senior manager-regulatory affairs in the AANS/CNS Washington Office.