Ushering in a new era in medicine, the U.S. Food and Drug Administration said Friday that it had cleared the way for the world's first clinical trial of a therapy derived from human embryonic stem cells.
By early summer, a handful of patients with severe spinal cord injuries will be eligible for injections of specialized nerve cells designed to enable electrical signals to travel between the brain and the rest of the body. When the cells were administered to rats that had lost control of their hind legs, they regained the ability to walk and run, albeit with a limp.
As a Phase I trial, the study will primarily assess the safety of the treatment, which has been under development by Menlo Park, Calif.-based Geron Corp. for nearly a decade. But scientists, doctors and patients said they were most eager to see whether low doses of the cells would produce any therapeutic benefit.
If so, it would help validate years of hope and investment in the nascent field of regenerative medicine. Besides patients with spinal cord injuries, stem cell therapies could ultimately benefit people with such intractable diseases as Alzheimer's, Parkinson's and multiple sclerosis.
The cell therapy is made from one of the first batches of human embryonic stem cells ever created. Researchers had feared those cells could never be used to treat people because they were derived using molecules from mice and cows and thus might be rejected by the human immune system. Newer stem cell lines that are animal-free have not been eligible for federal research funding under the policy set by President Bush in 2001. As a result, many people had expected FDA approval for any embryonic stem cell therapy to be years away.
Now, however, the FDA appears satisfied that the stem cells are safe for human use, and more clinical trials are sure to follow, said Amy Comstock Rick, president of the Coalition for the Advancement of Medical Research, a patient advocacy group that supports stem cell research. "It shows that things are starting to move through the pipeline," she said.
Dr. Thomas Okarma, Geron's chief executive, said the timing of the FDA's decision -- made late Wednesday but announced Friday by the company -- had nothing to do with the change of administrations in Washington. Unlike Bush, President Obama has voiced strong support for human embryonic stem cell research.
