Landmark ALS stem cell trial moving into a critical phase

Neuralstem's groundbreaking clinical trial of a stem cell therapy for Lou Gehrig's disease, or ALS, has hit a critical juncture. After sizing up the safety profile of the therapy in the first batch of patients treated in the study, investigators are preparing to take the next step: Moving from the lower to the upper part of the spinal cord and injecting stem cells in the hopes of protecting nerve cells required for breathing.

When the FDA offered a green light for the study back in the fall of 2009, investors pushed up the value of Neuralstem's shares by 57 percent. Since then the trial has been playing out at a painstakingly measured pace as researchers first set out to see if this radical new approach to ALS is safe for patients. Once regulators sign off, the principal investigator tells the Detroit News, she can begin to see if the treatment will offer an important survival benefit.

"Up until now, we've been targeting the lower part of the spine and if the therapy was effective--and that's only if--what would be retained would be the ability to walk," says Dr. Eva L. Feldman, the principal investigator. "Walking is not necessarily essential for survival. What is essential for survival is the ability to breathe." And while Feldman has been careful not to tout the potential for a cure or overstate the possible benefits of the therapy, she's consistently believed that stem cell therapy offers a big advance.

"In work with animals, these spinal cord stem cells both protected at-risk motor neurons and made connections to the neurons controlling muscles," she said back in 2009. "We don't want to raise expectations unduly, but we believe these stem cells could produce similar results in patients with ALS."

At Bio-Europe Spring in Milan, Neuralstem CEO Richard Garr noted today that the first 12 patients in the study will be treated by April, when Feldman will unveil results at an upcoming scientific meeting. While the Phase I study endpoint is focused on safety, investigators are also tracking several key secondary endpoints on efficacy, including motor function and respiratory impact. And Neuralstem plans to file an IND for a separate early-stage stroke trial in April. The stroke trial will use the same technology involved in the ALS study, says Garr, but probably won't be cleared until regulators have a chance to review the first safety data.

Says Garr: "The FDA is making is move very slow." But because investigators are working with patients early on, he adds, the company can gain some early insights on efficacy that will help advance later stage work.

Several early stage stem cell trials are now underway in the U.S. On Monday StemCells announced that it had launched the first study of a neural stem cell injection for spinal cord damage. And Geron is conducting the world's first study of an embryonic stem cell treatment for spinal cord damage. StemCells will recruit a dozen patients with injuries which are three to 12 months old.

- here's the story from the Detroit News