NCHR Testimony at the FDA about New Spine Device, Barricaid Anular Closure

Three to 5 % of the US population are affected by lumbosacral radiculopathy and the vast majority can be managed conservatively. If indicated, simple discectomy is the most common surgical treatment option. However, it is unclear if it prevents back or leg pain from persisting or returning beyond 2 years after the procedure.

The Barricaid device is first-of-its-kind, but since the surgery itself has unclear benefits, the device should only be approved if it adds a proven meaningful benefit for patients. There is evidence of benefit at 24 months post-op. However, the trial failed to demonstrate benefits in the long run, and raised many concerns of potential harm.  Patients deserve better evidence.

We have several major concerns.

 #1. If approved, Barricaid would be indicated for anular closure following limited discectomy. Yet, in the study, 62% of surgeries included carving out the anulus, a more extensive surgery. In other words, the proposed indication does not match up with the surgery for which the device was tested.

 This raises important questions: 1) How effective is the device at closing natural anular defects without anulotomy? 2) Was anulotomy responsible for the increased reherniation seen in both Barricaid and control subjects?

#2. Long-term performance data do not indicate effectiveness. It is worrisome that the device had a somewhat superior outcome at 24 months post-op but not after that, because we already know that the benefits of surgery decrease after 2 years.  Patients need a way to prevent their back pain and symptoms from coming back or a way to postpone the need for a second surgery. The long-term data do not demonstrate that the device meets either of these needs. The FDA’s analysis indicates that 50% of Barricaid subjects had reherniation compared to 70% control, however, the 20% advantage of Barricaid over surgery alone drops down to a nonsignificant 6% in the long run. In addition, although there was a decrease in second surgeries in the Barricaid group (9% vs. 16%) during the first 24 months, there were numerous second surgeries in the Barricaid patients that occurred after 24 months that should be counted as failures. And, the Barricaid patients had more second surgeries that required implanting hardware –a higher risk procedure. 

The FDA should require the sponsor to demonstrate benefit beyond the initial 24 months BEFORE approving this device.

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#3. We have concerns that this device could do more harm than good. There were substantial device integrity failures, including device fracture and migration. The sponsor asserts that even those patients still had “mostly positive clinical outcomes.” That raises questions about the value of the device:  if the device fails but the patient does well, doesn’t that suggest that it is the surgery that is beneficial, not the device?

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We’re especially concerned that Barricaid patients had nearly twice the percentage of EPLs (end-plate lesions), and the EPLs had more worrisome features with bone erosion likely caused by the implant. The data also suggest that EPLs contribute to re-herniations. Bone erosions can cause serious harms, such as elevated blood calcium levels, increased inflammation, or disruption of normal processes involved in bone build up/break down.  Will these cause bone fractures or cancer?  We need 5-year data to assess these potential risks BEFORE approval.

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#4. The lack of blinding raises questions about the integrity of the data. If the primary endpoint is based on findings seen on Xray, then not blinding the subjects is not of concern. However, the composite assessment included patients reports, and those patients knew they were getting a new device, and that could have biased their reports. Since the sponsor said it was not possible to blind outside the US, the FDA should require blinded studies (at least single blind) on US patients to minimize the risk of bias.