During a livestreamed “show-and-tell” presentation last November, Elon Musk, in his capacity as CEO and co-founder of Neuralink, claimed that the brain-computer interface startup was mere months away from beginning in-human trials of its brain implant.
That timeline—already pushed back several times from Musk’s initial predictions that human studies would begin by the end of 2020—has now been cast into doubt, as Reuters reported Thursday that Neuralink’s request to begin clinical trials was rejected by the FDA a year ago. The previously unknown update came from seven unnamed current and former employees, several of whom expressed doubt to Reuters that Neuralink could resolve issues raised by the FDA in time to meet Musk’s latest deadline.
During the November event, he suggested that the planned human study could kick off as soon as May of this year.
“We’ve been working hard to be ready for our first human,” he said at the time. “Obviously, we want to be extremely careful and certain that it will work well before putting our device in a human, but we’ve submitted, I think, most of our paperwork to the FDA, and we think probably in about six months we should be able to have our first Neuralink in a human.”
Neuralink’s flagship product is a small device that’s meant to be implanted in the place of a removed section of skull—a process conducted by the company’s custom-made surgical robots. The implant was named a breakthrough device by the FDA in mid-2020, a designation that prioritizes agency feedback to companies that are developing much-needed technologies to treat serious illnesses and other conditions.
Musk said in November that the device would initially focus on two medical applications: restoring sight by tapping into the region of the brain responsible for vision and enabling people with severe paralysis to “operate their phone faster than someone who has working hands.”
From there, according to the entrepreneur, the brain-computer interface technology could one day help restore movement to those paralysis patients: “We’re confident there are no physical limitations to enabling full-body functionality,” Musk said. “As miraculous as it may sound, we’re confident that it is possible to restore full-body functionality to someone who has a severed spinal cord.”
But if those feats sound too good to be true, that’s because they just might be—for now, at least. The Neuralink staffers told Reuters that in its rejection of a human trial, the FDA cited “dozens of issues” that needed to be addressed. They reportedly included several questions about the device’s safety, including whether it could be removed without causing damage to the brain, as well as concerns about the lithium makeup of its battery and the possibility that tiny wires attached to the implant could migrate beyond their designated positions on the brain.
According to a company document from last fall cited by Reuters, Neuralink was expecting to receive the FDA’s green light by March 7. But a handful of the outlet’s sources said they weren’t confident the agency would be giving Neuralink the go-ahead any time soon, with one calling any predictions of the approval’s timing a “gamble.”
Neuralink didn’t immediately respond to Fierce Medtech’s request for comment on the reported FDA rejection. The FDA doesn’t publish copies of the confidential rejection letters, nor is Neuralink required to disclose the regulatory update, since it’s still a private company.
While a rejection of the human trial application doesn’t completely shut down the possibility that Neuralink’s device may one day achieve Musk’s lofty goals, as Reuters noted, it does indicate the presence of significant obstacles to that success—contrary to the CEO’s seemingly undying optimism.
The latest report may also shed more light on rumors of tumult at the company. In August, Reuters cited four current and former Neuralink employees who said Musk had “expressed frustration” with the team over delays in the device’s development.
The August report also claimed that Musk had approached Thomas Oxley, CEO of Synchron, to offer a possible investment in the Neuralink competitor. Synchron’s brain-computer interface—which doesn’t require open-brain surgery or the removal of any piece of skull and is instead put in place via the jugular vein in a minimally invasive procedure—has already begun human trials in the U.S., it announced last July, after securing the FDA’s blessing in 2021.
The report of Neuralink’s alleged human trial setback also comes not long after the U.S. Department of Agriculture’s inspector general launched an investigation into its animal studies of the device.
The probe stems from claims made by an animal cruelty prevention group at the start of 2022 that the company regularly denied needed physical and medical care to the nearly two dozen macaque monkeys that have been implanted with the tech. Further reports alleged that while many of the approximately 1,500 deaths of Neuralink animals since 2018 can be attributed to normal research processes, a handful were linked to human error, possibly pushed along by the high-pressure environment that Musk has reportedly created at the company.
Neuralink has denied all accusations of animal abuse; during the November show-and-tell session, Musk made a point of highlighting the treats given to its subjects, saying, “I’m pretty sure our monkeys are pretty happy.”