Synchron Pauses Trials of Its Brain Implant Due to Performance Issues

Save Story Save this story Save Story Save this story Brain implant company Synchron has paused clinical trials of its second-generation device after it failed to perform as expected in initial study participants, WIRED has learned. The Brooklyn-based startup, a competitor to Elon Musk’s Neuralink , is also undergoing a restructuring, which includes eliminating jobs and scaling back its footprint in New York while building up a team in San Diego to support the development of an entirely new device. Synchron is one of several companies developing brain-computer interface technology meant to allow people to control digital devices by reading brain signals and translating those signals into output commands. The company has touted its technology, dubbed the Stentrode, as minimally invasive since it does not rest in the brain itself or require brain surgery. Instead, the stent-like mesh tube is inserted into the jugular vein at the base of the neck, then guided with a catheter to sit on top of the brain’s motor cortex. The company’s first-generation Stentrode connected using an external wire resting on a user’s chest. Ten volunteers across the US and Australia received that device and were able to send emails, text, browse the internet, and do online shopping and banking with their thoughts. Synchron has also enabled volunteers to control an Amazon Alexa and Apple’s iPad and Vision Pro without using their hands or voice. Synchron’s second-generation device has fewer electrodes and is fully wireless, using Bluetooth to connect. The company launched a multisite trial in the US earlier this spring with sister sites in Australia and Canada to evaluate the newer Stentrode, and some participants have already had it implanted. Those sites have recently paused enrollment, however, because the device is not working as intended, according to sources familiar with the trials who asked to remain anonymous. In a statement to WIRED, Synchron says it voluntarily paused enrollment “after identifying a performance issue involving the lead, the cable that carries signals from the Stentrode to the implanted electronics.” “The issue does not involve the Stentrode itself and no safety issues related to the device have been identified. The pause was a company decision, not an FDA-directed action,” the statement continues. The company says it has since brought lead design and manufacturing in-house. Instead of fixing the lead alone, Synchron says it is upgrading the whole Stentrode system and will resume trial enrollment once the hardware upgrades are complete. “We will continue to support participants with Stentrode devices across their lifetime. Our commitment to their care and well-being remains unchanged,” Synchron says. Got a Tip? Do you know something we should know? We’d like to hear from you. Using a nonwork phone or computer, contact the reporter securely on Signal at emullin.06. Two of the five US trial sites that WIRED was able to reach confirmed that recruitment is on hold at those locations. A coordinator at one site said the pause was not safety-related and was due to Synchron taking a look at the device to make sure the company is getting the readouts it is looking for. These trials are key to Synchron advancing the Stentrode into a larger pivotal trial, which is needed for the US Food and Drug Administration to grant marketing approval. “We still have strong confidence that it has the potential to be a first-line therapy,” CEO Tom Oxley says of the Stentrode. Synchron’s website and LinkedIn page show around a dozen job openings in San Diego, including electrical and mechanical engineers, microchip designers, and materials scientists. The San Diego team will be designing and manufacturing the upgraded lead and Stentrode, as well as a separate device that the company has not yet revealed that will go “beyond the blood vessels altogether,” according to its website. Oxley previously told WIRED that the company was planning to develop a device that reaches multiple brain regions at once, which could allow more complex and natural functions beyond moving a cursor or making a mouse click. The brain-computer interface field is expanding rapidly, with money pouring into companies pursuing both implanted devices and wearables. Synchron was estimated to have a nearly $1 billion valuation after closing a $200 million funding round last fall. It is backed by Khosla Ventures and the venture firms of Bill Gates and Jeff Bezos. Neuralink was reportedly valued as high as $42 billion in secondary market transactions as of this summer. The company had an early problem with its implant in 2024 after it malfunctioned in its first volunteer, Noland Arbaugh. The coin-sized device sits in the skull and has 64 tiny, flexible wires that are threaded into the brain. A few weeks after Arbaugh received the device, several of the wires came out of his brain, leading to a loss of cursor control. Neuralink was able to compensate for the lost threads and restore control by modifying its recording algorithm. Recent advances in artificial intelligence are fueling the development of brain-computer interfaces since AI models can read brain patterns faster and more accurately than traditional algorithms. Merge Labs, a brain-computer interface company cofounded by OpenAI CEO Sam Altman, came out of stealth in January with $252 million in funding. OpenAI provided some of the funding, and the two companies are collaborating on AI models. While these devices have shown incredible promise for people with severe motor disorders, they remain experimental. Synchron’s setback shows just how far the field still has to go before these systems are commercially available for patients.