May 20 (UPI) -- An existing drug could help limit damage caused by an injury to the spinal cord by blocking the inflammatory response, potentially restoring some movement, researchers said Friday.
The drug, called AZD1236 and developed by the pharmaceutical firm AstraZeneca, can reduce the "secondary damage" generated by the body's response to spinal cord injury, they said in an article published Friday by the journal Clinical and Translational Medicine.
In animal experiments, AZD1236 promoted nerve regeneration, with 80% preservation in nerve function following spinal cord compression injury, which can occur following motor vehicle accidents or falls, the data showed.
This translated into an 85% improvement in movement and sensation following three days of treatment with AZD1236 and starting within 24 hours post-injury, according to the researchers.
Within three weeks, the AZD1236-treated animals showed recovered much of their nerve sensation and function, they said.
"Currently there are no reparative cures for spinal cord injury but only treatments that reduce their symptoms," study co-author Dr. Zubair Ahmed told UPI in an email.
The drug represents a "potential treatment that can stop the major consequences of spinal cord injury, namely swelling of the spinal cord and breakdown of blood vessels in the spinal cord," said Ahmed, professor of neuroscience at the University of Birmingham in England.
About 18,000 people in the United States suffer spinal cord compression injuries annually, and more than 250,000 are living with the effects of these injuries, according to the National Spinal Cord Injury Statistical Center at the University of Alabama-Birmingham.
There is no treatment that permanently or completely restores nerve sensation and function, though researchers have been experimenting with drugs as well as surgical implants.
One of the key drivers of the secondary damage that occurs following a spinal cord injury is the breakdown of the blood-spinal cord barrier, Ahmed and his colleagues said.
This leads to edema, or excess fluid build-up around the spinal cord, which causes an inflammatory response that can limit healing and nerve cell death.
AZD1236 is designed to block two enzymes, MMP-9 and MMP-12, that are involved in inflammation, which gives it the ability to stop edema, limit breakdown of the blood-spinal cord barrier and reduce scarring at the site of the injury, according to the researchers.
Oral dosing of the drug reduced enzyme activity by 90% in blood and by up to 74% in cerebrospinal fluid, while injecting directly into the spine did so by up to 90%, the data showed.
AZD1236 also suppressed the formation of proteins involved in inflammation that produce nerve pain following spinal cord injury by up to 90%, while it alleviated neuropathic pain sensitivity to cold, heat and touch by 82%, the researchers said.
University of Birmingham Enterprise, a school-affiliated initiative that connects academic research with financial support, has filed a patent application for the use of AZD1236 in the treatment of spinal cord injury and is seeking investors and partners to help bring it to clinical trials.
They are already prepared to conduct Phase 2 trials, the second stage of the development process, which will take two years to complete, according to Ahmed.
If those are successful, a full Phase 3 trial, the final step in the process, could be started in two years and "if all goes well as we believe it will, this drug could be ready for use by spinal cord injured patients in approximately five years," he said.
"Safety studies have already been performed with this drug in humans and the drug was extremely well tolerated at clinically relevant doses for up to six weeks," Ahmed told UPI.
"We believe that the drug has the potential to be a game-changer in the treatment of spinal cord injury," he said.