The new drug by Geron will be injected into patients within seven days of a spinal cord injury.
The stem cell treatment has been able to regenerate nerve fibers in laboratory animals, replacing damaged ones. Once that occurs, nerve sensation and mobility are restored.
Testing on humans will begin soon at Stanford Medical Center and six other facilities.
Neurosurgeon Dr. Gary Steinberg will be leading the study.
"The most important thing is to insure that these transplant trials do not cause tumors or other adverse effects. We're optimistic that once you get beyond the safety studies, we'll move quickly into efficacy studies," Steinberg said.
Testing had been suspended for almost a year when small cysts formed in lab animals. Geron says it has removed unwanted cells in the drug.
Karen Miner, whose spinal cord was injured in a car accident 17 years ago, says she is happy the trials are resuming. She would welcome even a small benefit from this drug or a future one.
"For me, if I could transfer from my chair to the sofa or to my bed, it would be wonderful, it would be huge for me," Miner said.
Geron believes its new drug has the potential for treatment beyond spinal cord injuries. It is doing lab tests to see if it will also work on nervous system diseases, including Alzheimer's and multiple sclerosis.
"I would predict over the next decade, probably the next 10 years, that we will start to see clinical outcomes improved with this cellular therapy," Steinberg said.
Besides the Geron drug tests, Stanford Medical Center will be gearing up as well for other tests looking at stem cell related drugs that could help stroke victims. It just received a $20 million research grant from California's Institute for Regenerative Medicine.