Forty-three people who are quadriplegic due to spinal cord injuries have partially recovered control of their hands with a device that applies electrical stimuli to the injured neurons, according to the results of a clinical trial presented yesterday in the journal Nature Medicine. The company Onward Medical, which has developed the device, expects it to be approved at the end of this year in the US and in 2025 in the European Union.

“A lot of people think you want to walk again, but the hands are what matters most,” Melanie Reid, one of the participants in the clinical trial, who suffered a spinal cord injury when she went falling off a horse fourteen years ago, when he was 52. Reid emphasized the importance of “putting your hand in your mouth to feed yourself” or “scrolling on a tablet or mobile”. According to Reid, “small improvements [in hand control] make a big difference.”

The ARC-EX device applies electrical stimuli with electrodes placed on the skin in the cervical region, where the spinal cord injury occurred. It works in cases where the spinal cord is not completely severed and neurons remain connected between the brain and the hands. The aim of neurostimulation, designed to be applied as a physiotherapy treatment and so that patients can continue applying it later at home, is to reactivate these neurons.

In the clinical trial, 60 patients from the United States, Canada and the United Kingdom have received the treatment. All of them had suffered the spinal cord injury at least a year before and had undergone rehabilitation therapies during the first months to recover as much as possible the functionality of the hands.

They received an average of 25 one-hour neurostimulation sessions. “Like any other type of therapy, it’s tedious; but when you start to see changes, it’s motivating,” said Sherown Campbell, another participant in the study, who became a quadriplegic in 2014 doing a combat sport with a friend, at the press conference.

After the sessions planned for the clinical trial were over, 43 participants (72%) had experienced increases in strength and improvements in function in their hands and arms. Eleven more had improved in one of the two, strength or function (but the treatment did not achieve the efficacy goals that had been defined before starting the study, which required improvement in both aspects). The other six patients did not improve in either.

Feature enhancements included grasping and finger pinching actions. For example, lifting glasses full of water, pressing buttons on a remote control, using a fork or inserting a key into a lock.

Fifty-two of the study participants (87%) said they had experienced a significant improvement in quality of life. Also that they felt less dependent on other people, that they improved in sleep quality, in pain reduction and in sensations of the upper trunk, including sensations of touch.

“It has been important for me to be able to help cook at home and prepare balloons for my children’s birthday parties,” Sherown Campbell explained.

Unlike other rehabilitation therapies for people with spinal cord injuries, which achieve improvements during the first months and then stagnate, with the ARC-EX device the improvement has been increasing until the end of the study. If the study had continued, it is likely that the improvement would have been greater, the researchers point out.

According to Grégoire Courtine, neuroscientist at the University Hospital of Lausanne (Switzerland) and co-founder of Onward Medical, “with the stimulation [of ARC-EX] we observe the growth of new neural connections”, therefore, the more applies the treatment, the more connections are formed and the greater the improvement patients experience. The device, Courtine explained, is designed to be used by people with manual disabilities, with the idea that users “can use it at home to maintain and improve recovery.”

With the results of the clinical trial, Onward Medical has applied to the US Food and Drug Administration (FDA) for authorization to market ARC-EX as a breakthrough therapy, a formula that allows accelerating approval of therapies for serious disorders when preliminary clinical results indicate substantial improvement. “We hope to be able to commercialize it before the end of the year in the US,” Courtine said at the press conference. Subsequently, Onward Medical will request approval from the European Union.

The price has not yet been set, Courtine informed, “but the idea is to make it accessible.”

Courtine’s team at the Lausanne University Hospital and Onward Technical is also developing neurostimulation technology based on a spinal cord implant that receives information from the brain and transmits it to the legs. This technology has been successfully tested in people with paraplegia and Parkinson’s, who have regained the ability to walk.

Looking ahead, implantable technology will be more precise and can apply neurostimulation throughout the day, so it “may improve activities of daily living more” than physical therapy, Courtine said. But ARC-EX, he pointed out, has the advantage of being a non-invasive technology, which can be applied on a large scale in physiotherapy consultations and which at this time can reach a larger number of patients in a faster way .

For Melanie Reid, “after fourteen years [since the spinal cord injury], I thought nothing would change. To suddenly realize that I had more strength in my fingers and thumb was extraordinary. It’s something that makes you go with your head held high and see life a little differently.”