Yesterday’s release by the FDA of a warning letter it sent ReWalk Robotics demanding a revised postmarking trial plan for its powered exoskeleton is the second blow in a week for the company. Its disappointing annual results, released last Thursday, knocked its shares down 11%; a further 13% drop, to $9.07, occurred on Tuesday.
It transpires that the FDA’s letter to ReWalk, sent in September, was the last in a line of complaints focusing on the company’s failure to provide a robust plan for assessing the potential damage to users if the device was unable to prevent a fall. The company does not appear to have disclosed receipt of the warning letter to its shareholders.
The ReWalk exoskeleton was approved in June 2014 under a de novo 510(k) clearance submitted by the company under its previous name, Argo Medical Technologies. This kind of clearance is used for low-risk products that are too unlike anything previously approved to be able to use a predicate. It is less rigorous than the premarket approval process, which is used for similarly innovative, but higher risk, devices.
When the device was approved in June 2014 the FDA highlighted the risk of “instability, falls, and associated injuries”, with clinical testing listed as the first mitigating measure ReWalk – which was previously called Argo Medical Technologies – was advised to take.
This risk is what has prompted the September letter, the FDA wrote. If a user fell, the agency said, they could suffer a serious injury or death owing to traumatic brain injury, spinal cord injury or fractures. The FDA also noted that an individual assisting the user could also be harmed.
Since the clearance was granted, ReWalk has submitted two post-market surveillance study plans to the FDA, neither of which the agency found satisfactory, saying that they lacked sufficient information.
Since then the story, according to the FDA, appears to be one of missed deadlines, broken promises, unanswered emails and un-picked-up telephones.
The upshot is that the FDA has apparently still not received a postmarket study plan containing all the information it wants. And the final deadline has passed: the Federal Food, Drug and Cosmetic Act calls for a manufacturer to commence surveillance not later than 15 months after approval. In ReWalk’s case, this period expired on September 28, 2015.
None of this seems to have been communicated to ReWalk’s shareholders.
Failure to comply
So what happens now? The agency says the company has “committed a prohibited act” by failing to comply, and the exoskeleton is now “misbranded”. The agency may now take regulatory action, possibly including “seizure, injunction, and/or civil money penalties”.
It is not known whether ReWalk has responded to the FDA since September, but the group is currently conducting three clinical trials of its exoskeleton – judging by those listed on Clinicaltrials.gov that have been verified in the last six months – and a fourth, of a more advanced version, is planned.
Perhaps ReWalk has since taken action to fix the situation. Back in December the US Department of Veterans Affairs said that it would reimburse the exoskeleton for all qualifying veterans with spinal cord injury in the US. The FDA’s warning letter stated that “Federal agencies are advised of the issuance of all Warning Letters about devices so that they may take this information into account when considering the award of contracts”.
ReWalk’s product is the most advanced powered exoskeleton, so it is not likely that other groups developing similar technologies, which include Rex Bionics and Ekso Bionics, will be able to immediately capitalise on ReWalk’s woes. They might, however, be able to draw some conclusions about how best to communicate with the FDA.