After Setbacks, a Pioneering Stem-Cell Technology Is Back in Human Trials

Can cell therapy help spinal-cord injury? A long-running study hopes the answer is yes.

• by Katherine Bourzac
 
• September 14, 2016

A company that stepped in to salvage the first-ever medical use of human embryonic stem cells says it has encouraging results in patients with spinal-cord injury.

Today, Asterias Biotherapeutics, the company in Fremont, California, that's developing the treatment, will present data it says shows some gains of movement and sensation in five patients with spinal injuries who received injections of nervous system cells.

The company’s technology is notable because of its link to the original discovery of human embryonic stem cells nearly 20 years ago. These cells, derived from very early embryos, can be grown to form most other tissue types, including oligodendrocytes, which are support cells that have a role in protecting nerves. Those are the kinds of cells that Asterias is manufacturing.

Jane Lebkowski, chief scientific officer of Asterias, says the company thinks injecting such support cells into the spinal column can limit or reverse nerve damage, although not by directly growing new nerves. Based on animal studies, the company believes the cells prevent existing nerves from dying. “We want to show we can get neurological improvement,” she says.

Some remain skeptical of stem-cell therapies. Keith Tansey, a neurologist at the Methodist Rehabilitation Center in Jackson, Mississippi, says because cell transplants are still poorly understood, injecting them into spinal-cord injuries is “a Hail Mary—just throw it in there and hope it works.”

Doctors injected either five million or 10 million cells into the spines of volunteers. Of the patients treated with the higher dose, all five improved on certain motor functions, according to Charles Liu, director of the University of Southern California’s Neurorestoration Center in Los Angeles, who will present the results at the 55th Annual Scientific Meeting of the International Spinal Cord Society, being held in Vienna.

The study traces back to the original discovery of human embryonic stem cells in 1998, research that was sponsored by the pioneering biotech company Geron. When Geron launched the first attempt to find a medical application for the cells, in 2010, it chose spinal injury, but after treating several patients in a safety study, it canceled the program.

The project was later purchased by Asterias and its parent company, BioTime, which is headed by Geron’s former CEO, Michael West. In 2014, Asterias won a $14.3 million award from the California Institute of Regenerative Medicine, a state agency, to begin the current trial, called SCiStar.

The study was designed to test an escalating dose of the cells, but since it didn’t include any control subjects, it’s difficult to attribute improvements to the treatment. Tansey, who is president-elect of the American Spinal Injury Association, says he will remain cautious until the company can show results in a blinded study, in which some patients get the treatment and others don’t. Asterias says it plans to do that type of trial if the current effort is successful.

https://www.technologyreview.com