The Promise of Epidural Stimulation

By |2018-03-27T16:18:17+00:00April 2nd, 2018|
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Kate WilletteIn December, I received a forwarded email that originated in Thailand and was first sent to a young Californian with quadriplegia. He was so excited that he forwarded it to everyone he could think of, and eventually it found its way to me. Here’s how it began:

I am very pleased to inform you that you have been accepted for Unique Access’ innovative Spinal Cord Injury Epidural Stimulation and stem cell treatment protocol.

A couple of weeks later, I heard this in a private conversation with Kathy Allen, a T8 complete para from Minnesota:

I have the [epidural stimulator] device … while the feet/toe movement is not all that fantastic, my core area is unreal. I can get dressed, shower, wheel up and down ramps like I am not paralyzed at all. When I ride in the van, my core and legs are very happy. My balance is so good. I sit straight in the chair.

There’s a lot going on in the world of epidural stimulation. Like many of you, I’ve been watching the ES news since Rob Summers’ groundbreaking successful implant first appeared online: May 19, 2011. At long last, a genuine breakthrough! A man with a chronic, motor-complete spinal cord injury had been able to move his feet by willing them to move.

In 2015, I wrote dozens of pages in Don’t Call it a Miracle about what ES is and isn’t. In brief, the stimulator is really four things:

• A small, flat array of electrodes.

• A pulse generator, a gizmo about half the size of a deck of cards.

• A wire that snakes the short distance through the body between the electrode array and the pulse generator.

• A hand-held remote control.

In 2011, Rob Summers embodied the promise of epidural stimulation when he stood.

In 2011, Rob Summers embodied the promise of epidural stimulation when he stood.

The electrode array is surgically implanted into the epidural space — the super-narrow gap between the dura, a membrane that protects the fragile cord and the bones of the spine. The pulse generator is sewn into the fleshy pad under the skin of the hip. The hand-held remote for the stimulator is how you give the pulse generator instructions on how much juice to pump out through the electrode array.

The ES delivers a tiny stream of electrons to the general region of the lumbar cord, where networks of healthy intact neurons seem to be just waiting for a little boost. The implantation is an outpatient procedure that takes less than 45 minutes. Three models of epidural stimulators are on the market in the United States, all FDA-approved and covered by Medicaid, Medicare, and private insurers as indicated for pain (not as a therapy or intervention for spinal cord injury). Since the 2011 success, we have two parallel storylines about ES, each of which is suggested by the quotes above.

The first story is about the research effort underway to better understand how ES works in people with SCI and do the work needed to get it on the market. The second is about a group overseas that is offering to implant the device right now, for a price. Kathy Allen is part of the research effort, while the Californian is hoping to take advantage of the immediate opportunity in Thailand.

Domestic Research

Kathy Allen, a current epidural stimulation research participant, reports greatly improved core control that benefits daily activities like bathing, dressing, wheeling and driving.

Kathy Allen, a current epidural stimulation research participant, reports greatly improved core control that benefits daily activities like bathing, dressing, wheeling and driving.

As of today, dozens of motor-complete volunteers at half a dozen labs have been implanted with these stimulators, and every one of them has reported some sort of measurable improvement with zero adverse side effects. You can find the current efforts by going to clinicaltrials.gov and typing “epidural stimulation” into the search box.

Improvements range from regained sexual function to temperature regulation through sweating to ease of bowel management to — yes — the ability to move feet, toes and legs. Allen got her stimulator in December 2017, at 11 years post-injury. She is one of what will be 100 people in a trial called E-STAND that’s being managed out of the Hennepin County Medical Center in Minneapolis. That trial is different in scope and aim from all the others.

Dr. David Darrow, one of the E-STAND principal investigators, says that optimization, or knowing how to program the stimulators, is all-important. The E-STAND trial is unique in that subjects get the stimulators implanted then go home to live their usual lives, with one difference. Darrow’s team has built an app that allows two-way Bluetooth communication to reset the controls on the device. Every one of the electrodes in the array has a huge range of settings: 160 different frequencies, 100 pulse widths, and 256 possible amplitudes, meaning there are millions of ways to configure the whole set.

Which setting is best?

Nobody knows. Darrow’s team is randomly choosing a launch set of parameters, and then using feedback in real time from the subjects to adjust them. They’re building out what they call a “clinical decision support system” — an impressive name for a tool doctors everywhere will be able to use as easily as a phone.

International Sales

What about the Californian and his Thailand adventure? I did some digging to find out more about Unique Access Medical. The businesses that call themselves Global Stem Cells and Epidural Stimulation Now are both owned by Unique Access Medical. Based in Singapore, UAM doesn’t provide any treatment or care themselves; its role is to recruit subjects and sell them on products that are then delivered by its professional partners in Bangkok. Before ES came on the scene, UAM mostly focused on persuading potential customers on the effectiveness of its stem cell treatments, claiming to cure everything from tinnitus to ALS.

They’re still offering those stem cell treatments. In fact, they’ve created a sort of package deal for people with spinal cord injury.

You can have an ES plus 30 days of rehab for $72,000. You have to pay $40,000 of that up front, with the balance due when you get to the hospital.

Or you can get the device, and they’ll throw in stem cell injections and another 10 days of rehab for an extra $20,000, making the total package $92,000.

The stem cells are mesenchymal cells, collected from umbilical cord blood and/or amniotic fluid. To my knowledge, there is not yet any reason to believe that injecting these cells into a damaged human cord will do anything to restore function, especially if they’re delivered long after injury. Less than a year ago, Stem Cells International published an article that says: “Mesenchymal Stem Cell transplantation is not an effective and reliable therapy for spinal cord injury so far …”

In other words, that science is in the early stages of development. To me, it seems unethical to charge people so much money for what is still not much more than a hope. The stimulator is different. We know that it helps, and sometimes a lot.

But there are a number of other practical things I struggle with when it comes to the idea of going to Bangkok for an ES that’s manufactured by an American company (Medtronic) headquartered in Minnesota:

• There is zero ability for follow up to adjust the settings on the device. That’s huge.

• In case of complications like infection at the implantation site or failure of the device, the person with SCI is on his own once he’s back home. There are no warranties or do-overs.

• The price is outrageous and beyond the reach of most of us.

• The data is lost to the community, which matters because data is what will make the ES widely available.

All that said, there are obviously people who are willing to do anything to get some functional return right now, and I’m not about to judge them. Speaking only for myself, it’s important to keep the larger goal front and center. I want to do the things that will speed up the process of getting these stimulators approved and insured and accessible to every last one of us. That’s what matters to me.

Making that happen more quickly means supporting the researchers with money or by helping them spread the information about what they’re doing in the labs. It means writing to the people at the FDA to let them know how important this is to us, and how impatiently we’re waiting to use it. It means joining others, like Unite 2 Fight Paralysis and the Christopher and Dana Reeve Foundation, in their efforts to get this done.

There’s so much work to do, and so many reasons to be hopeful. We’re just getting started.

Resources
• Christopher and Dana Reeve Foundation, christopherreeve.org
• E-STAND trial, estand.org
• Global Stem Cells, globalstemcells.com
• Stem Cells International article, ncbi.nlm.nih.gov/pmc/articles/PMC5467343
• Unite 2 Fight Paralysis, u2fp.org