Unfortunately, there are currently no known ways to reverse damage to the spinal cord, regardless of whether it results from a crush, concussion or transection (cut), and whether the injury is acute or chronic. Surgery is mostly confined to stabilizing the mechanics of the injured spine and decompressing the cord. Treatment currently focuses on preventing further injury and empowering people with an spinal cord injury to return to an active and productive life. Researchers are continually working on new treatments, including prostheses, electrical and bioactive stimulation, and medications, which may promote regeneration of nerve cells or improve the function of the nerves that remain after an spinal cord injury.
Medical and rehabilitation treatment of spinal cord injury patients has improved over the past thirty years so that these patients are surviving longer with their injuries than in the past. However, a surgical option aimed at regeneration and recovery of the spinal cord has not evolved. Patients suffer a two to five-fold increased likelihood of premature death compared to other injuries, and less than 1% experience full neurological recovery. The lack of surgical options is even worse for chronic lesions (lesions where the damage from an acute injury has become permanent). Surgical treatment of chronic spinal cord lesion is not even considered an unmet clinical need.
The term ‘golden hour’, often used in the military, refers to the fact that for many treatments, speed equals better recovery for patients. This is generally true after any traumatic injury, also after a stroke or heart attack. The window of opportunity depends on the type of injury and situation and usually several hours or even days.
Numerous approaches are being developed and have been tried to protect and regenerate neurons after spinal cord injury. Implantable scaffolds are considered to be a very promising approach and have been demonstrated as safe in clinical trials. Neurites from injury site stumps grow and reconnect as long as they are not inhibited by scar formation. However, it is currently impossible to generate and put in place a scaffold immediately after injury (24-72 hours), which would provide the greatest chance of at least partial recovery.
Scaffolds can provide a favorable environment to enhance and direct nerve regrowth, and suppress scar formation. They are frequently and successfully in peripheral nerve surgery, but their use is very limited for SCI treatment. Even the simplest scaffolds tend to be difficult to manufacture, handle, and implant. Their bulk nature makes them ineffective in joining with individual nerve endings and encouraging those to regrow. Most importantly, in order to place the implant, the patient’s spinal cord needs to be cut to size – which no neurotrauma surgeon ever wants to do. More advanced scaffold approaches need to be customized to the injury site shape and then printed / manufactured and implanted, all under sterile conditions. Doing so requires specialized equipment as well as skilled and risky surgical intervention on the spinal cord itself, beyond decompression and stabilization. Those resources are unavailable at most trauma centers.
No. Although this was a commonly held dogma for decades, recent and independent experiments clearly demonstrate that neuronal regrowth and functional regeneration are possible in the spinal cord and brain, given the right conditions. Several highly respected research groups have discovered multiple powerful and independent mechanisms that can ‘re-awaken’ dormant neurons, trigger them to regenerate, and stimulate their regrowth.
Spinal cord injury is a very complex condition – medically, physiologically, and on a biomolecular level. Numerous brilliant scientists at many companies and research institutions have dedicated their lives trying to make progress towards this elusive goal. While great progress is currently being made on many fronts, it appears that an ultimate solution for the treatment of spinal cord injury may require a combination of several different approaches that can address in parallel the many factors complicating the injury and healing process.
We believe our injectable scaffold can make an important contribution to the field of spinal cord injury research, and that our technology can also benefit other promising treatment approaches that have entered advanced animal studies or human clinical trials. Neurons need a protective biophysical environment to thrive, and they like to grow along fibers – not unlike ivy on a tree, or beans on a trellis. Axonal regrowth can successfully be stimulated and directed by many types of fibers. Most current scaffold designs indeed support regrowth, but they do to provide any directional guidance – neurons are not given any cues of where they should go to re-establish a functional reconnection. Some methods have tried to introduce pre-formed fibers into the injury site, but they do not address spinal cord motion, fibrinous clot formation and different viscosities of injured versus intact tissue and grey versus white matter. These factors prevent successful orientation of pre-fabricated fibers of sufficient length in situ. NeuroPair’s approach sidesteps these problems by forming a scaffold from a liquid entirely within the injury site.
NeuroPair’s ‘Fibermag’ injectable formulation forms oriented, flexible and biocompatible fibers directly in the injury site. The hydrogel-based formulation consists of two components (biocompatible nanoparticles and linkers) which are combined and mixed immediately before use. The particles are aligned into flexible chains, called ‘Fiberguides’, through a temporary magnetic field that is applied parallel to the intended direction of neuronal regrowth. The Fiberguides stabilize by biocompatible crosslinking and the magnetic field is removed. The entire sterile process can take place within 10-25 minutes. The resulting fiber scaffold automatically conforms to any irregular shape of the injury site – individual fiberguides interdigitate with neuronal ends on both sides of the injury site, facilitating their attachment for stimulation of regrowth and directional guidance, and the gel-based formulation helps to block scar formation physically.