Looking to the future

Ralph Quinlan Ford reports on a breakthrough treatment which could eventually offer hope for people with spinal injuries 

Irish Examiner
Published on: 13 August 2004

WHEN actor Christopher Reeves was paralysed in an equestrian competition in 1995, he not only put a human face on spinal cord injury but also motivated neuroscientists around the world to surmount the most complex diseases of the brain and central nervous system.

The last 10 years have seen extraordinary developments in the treatment of spinal cord injuries, and the regeneration of the central nervous system is no longer considered impossible. Although there is little evidence yet that the amount of regeneration required to restore functions such as the ability to walk at different speeds in humans can be achieved, tests on animals with complete spinal cord injuries have shown that the potential does exists.

Following most tissue injury, macrophages (white blood cells) quickly start to remove cell debris. They then start to secrete growth factors that promote a controlled inflammatory reaction to kick-start the wound healing process. While this process occurs effectively in most tissues including peripheral nerves, this is not the case when it comes to the central nervous system.

Discoveries led by Prof Michal Schwartz of the Weizmann Institute of Science at Rehovot in Israel have, however, shown in pre-clinical studies that specially treated macrophages promoted recovery from spinal cord injury (SCI). Based on these findings, Proneuron Biotechnologies Inc is now evaluating the safety and efficacy of ProCord — a macrophage incubating technology — as an experimental procedure for patients with acute spinal cord injury. The Israeli-based company has just finished Phase I of the clinical trials.

The idea is to draw blood from the patient, collect macrophages (a type of white blood cell) ‘treat and educate’ them and then, in a surgical procedure, inject them into the spinal cord for the purpose of stimulating a repair process. Specifically, blood and skin taken from the arm of the patient is processed in a Proneuron Cell Center for approximately one and a half days. Based on the results of the pre-clinical studies, the deadline for the technology is 14 days after the injury.

Melissa Holley and Justin Richardson, spinal injury patients from the Phase I trial, have regained feeling and muscle control. Both live alone, are active college students and manage their lives on their own. Recently they addressed a rally in New York for spinal cord injury research. Justin said, “It is my personal opinion that my involvement in this procedure has changed my life for the better and it may possibly one day help to serve as a stepping-stone towards the goal of a cure for spinal cord injury.”

Dr Angela McNamara, consultant in rehabilitation medicine at the National Rehabilitation Hospital says: “This is progress and the centres involved in the study are very reputable. As the number of patients in the studies is only 16 it may be too early yet to comment without significant numbers but the science does make sense. Research is going global to get bigger scientific data but I would say that this technology is still in the experimental stage. I look forward to results from the second trial. With studies like this and also those on stem cells, things may improve for people with spinal cord injury in years to come but more research is needed.”

David Snyder, Vice President of Clinical Development at Proneuron said, “There is a growing understanding in the scientific community that immune modulation is a powerful tool that could potentially treat many neurodegenerative diseases in addition to spinal cord injury. The fact that many leading clinical centres in the US, including the Mount Sinai Medical Centre in NY, are now enrolling for the Phase II study coupled with the reality that the FDA has agreed to its implementation, supports the school of thought that ProCord indeed may be a breakthrough therapy.”

He went on to say that, “The long term safety concerns expressed by some in the scientific community are gradually being alleviated as the first 16 people who received the procedure are now passing 12, 24 and even 36 months post treatment without any negative clinical signs or deterioration of the cord associated with the treatment.”

As yet the company is looking for an enrolment centre for Europe. In accordance with FDA guidelines and to ensure the integrity of the Phase II study, the company is now enrolling 61 patients. In a randomised-controlled clinical trial which this trial is there has to be a control to compare results against. So for every three patients enrolled in the study, only two will receive the new treatment.

Colm Whooley, Chief Executive of Spinal Injuries Ireland, said, “On a monthly basis there are breakthroughs which can give false hope to people with spinal cord injuries. This procedure is still not widely available as it is in research stage.

“If this becomes successful I would foresee that the National Rehabilitation Hospital will import this technology after it becomes part of the usual rehabilitation procedure. While I am being cautious I do also feel that the research is a good initiative.” Colm speaks from experience, as he himself sustained a spinal injury following a motor bike accident in 1980.