Hope for spinal cord injuries
October 28 1999

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Financial Times.

For a scientist about to begin the first clinical trial aimed at regenerating cells in severely damaged spinal cords, Adrian Harel is remarkably calm and modest.

Dr Harel, neurobiologist turned company manager of Proneuron Biotechnologies, a small clinic based at the Weizmann science park near Tel Aviv, is making final preparations for when his small team of physicians start trials next month in hospitals in Israel and later in Belgium.

The trials, which received the go-ahead last month from the US Food and Drug Administration, could provide hope for those with spinal cord injuries, similar to the severity that paralyzed Christopher Reeve, the former Superman actor.

In the US, there are between 11,000 and 12,000 spinal cord injuries each year, caused mostly by car accidents or sports. It is estimated that the health care costs per patients who do not recover exceed $750,000.

The reason for such hope, as Dr Harel explains, is that Proneuron's treatment relies entirely on blood and tissue from the patient.

"Until now, patients have been treated with steroids. Our treatment is based on cell therapy, using autologous cells - the patient's own cells - as opposed to drug therapy. We believe the efficiency will be higher and the side effects will be fewer," adds Mr. Harel.

The method used by Proneuron involves taking macrophages, or white blood cells from the patient.

The macrophages, which are natural regenerative cells that play a key role in the repair of any injured non-central nervous system tissue, are co-incubated with additional natural tissue - again taken from the patient.

Through a chemical process, the macrophages are activated and then reintroduced, through an injection, into a precise area of the damaged spinal cord.

Mr. Harel explains that through the incubation process, which lasts 24 hours, the cells are "educated".

"They are targeted. They know where they have to go and what they have to do once they are reintroduced into the patient." Once injected, the macrophages secrete chemicals that eat all the dead cells in the injured central nervous system, remove them and create the path for the growth of axons - the long threadlike parts of nerve cells. Through this process, spinal wounds are repaired.

At least that was the result with Proneuron's trials with rats. After receiving such treatment for spinal cords that were literally broken in two, the rats were able to move their hind legs.

"The trials with the rats were positive," says Jacques Brotchi, head of the neurosurgery department at Brussels' Erasmus University Hospital.

Prof Brotchi, a specialist in spinal cord surgery, recently agreed to team up with Proneuron to conduct next month's trials.

"For people who are already paralyzed, we have nothing, except high doses of steroids," explains Prof Brotchi. Yet even for those patients, he added, Proneuron's treatment cannot be used.

The treatment must be applied between the fifth and fourteenth day of the accident. This "window of opportunity" - as agreed by the FDA - is important for two reasons.

Prof Brotchi says that sometimes the patient has trauma and can then recover.

The physician must therefore wait. Treatment, however, cannot be delayed for more than 14 days since cells start to die and muscles deteriorate.

But to assess the results of the trials, nothing must be working in the spinal cord. "Our patients will have complete spinal cord injuries - in other words, they cannot recover by themselves," says Dr Harel.

Dr Harel remains anxious not to raise expectations. Indeed, he cautions that the treatment is not aimed at full recovery. "It is to slow down, or stop the degeneration," he says.

But for experts in the field, that offers much hope for patients.