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Neurostimulator to Treat Stroke Does Not Get FDA Advisory Board Support


Dive brief:

  • BrainsGate’s neurostimulation device for increasing blood flow to the brain and reducing disability in stroke patients has not been shown to be effective in scientific evidence submitted to the FDA in a pre-market application, an advisory group concluded with the agency after a one-day meeting on Friday.
  • The Neurological Devices Panel decided by a vote of 7-3, with three abstentions, that the benefits of the treatment did not outweigh the risks to the patients in the BrainsGate submission. Reasonable assurance of effectiveness has not been demonstrated, the panel also determined in a 7-3-3 vote.
  • Panelists who were unconvinced of the device’s effectiveness disputed changes to the pivotal trial at the end of the study that they said could have compromised the results. However, panel members voted unanimously to find reasonable assurance of the device’s security.

Dive overview:

Israel-based BrainsGate, which has attracted early investment funding from Boston Scientific and Johnson & Johnson, has developed its neurostimulation device as an option for patients who are not eligible for currently available treatments for severe ischemic stroke, or who arrive at the hospital after the end of the treatment window. firm. These patients face the potential for severe disability.

Current therapies involve intravenous drugs or endovascular thrombectomy to remove the clot. However, the success of these approaches depends on the speed of access to the hospital.

Patients with stroke should be treated within 3 to 4.5 hours of starting drug therapy and within 6 to 24 hours for thrombectomy. The potential benefits diminish over time, increasing the risk of intracranial hemorrhage. The guidelines leave only 2-3% of people who present to the hospital 8 hours to 24 hours after a stroke eligible for a thrombectomy.

The BrainsGate device was intended to provide an alternative for people seeking help 8 hours to 24 hours after suffering a stroke. The neurostimulator is implanted in the hard palate of the mouth and activated by an external system that delivers electrical impulses to the sphenopalatine ganglion, a group of nerve cells linked to the trigeminal nerve. Patients receive 4 hours of treatment per day for five days, then the device is removed.

One option for stroke patients who arrive at hospital after the current treatment time has expired is clearly an unmet need, several experts from the Neurological Device Panel said on Friday.

“We are desperately looking for something to give these patients outside of a window. Most likely it will be widely applied, but that sets the bar high,” said David Kennedy, panel member, Vanderbilt University Medical Center.

The BrainsGate treatment, however, hit a stumbling block when the device’s pivotal trial failed to meet its primary endpoint. The research, published in 2019 in The Lancet, showed that the neurostimulator is likely to improve functional outcomes in patients, but the results were not statistically significant.

In documents released ahead of Friday’s meeting, the FDA highlighted several concerns about the study, including an imbalance between treatment groups that occurred when investigators failed to implant the device in some patients as well. only inaccuracies found in a model used to evaluate the results of the study.

The FDA has expressed unease with the significant changes made to the study design and the device itself at the end of the research. Most of the changes were implemented in the final year of the study after more than 1,000 patients were randomized, the agency noted.

“A change in design and clinical use during a study can affect efficacy and safety,” the FDA said. The agency also said it was concerned that the risks associated with the implantation may have been under-represented in clinical studies.

It was the late changes to the trial design that most troubled many of the panelists. They said they would have liked to see stronger evidence of effectiveness, and some have called for a follow-up study. “It’s a little disturbing that it’s not more robust,” said Earl Ray Dorsey, a panel member from the University of Rochester.

The FDA will now consider the advisory group’s comments before deciding on next steps. The agency often seeks advice from its advisory committees, but is not required to do so.