CHICAGO – The U.S. Food and Drug Administration said Friday that a California-based company can begin the nation’s first human clinical trials using embryonic stem cells.

Geron Corp. will this year begin such cells in a clinical trial of spinal cord patients. If Geron’s trials are successful, it opens the door to new therapies and drug discoveries that many believe the Bush administration stymied because it had banned the use of federal funds for such research. Geron, however, has used its own money and that of investors.

“This marks the beginning of what is potentially a new chapter in medical therapeutics – one that reaches beyond pills to a new level of healing: the restoration of organ and tissue function achieved by the injection of healthy replacement cells,” Geron chief executive officer Dr. Thomas Okarma said Friday.

Because there is no federal money for this kind of research, there has been little movement in the embryonic stem cell arena outside of Geron’s privately funded effort. That means regulators lack the data needed as comparison to Geron’s studies, further slowing the clinical trial approval process.

Geron’s chief executive told the Chicago Tribune in November that the FDA took longer to review Geron’s application because complexity of stem cell products. Other stem-cell trials using adult-derived stem cells are well under way although such a product has yet to be approved by the agency.

“We have submitted all Geron publications because there is no NIH-funded literature to compare it to,” Okarma told the Tribune in November. “The FDA has to go through every page with a fine-tooth comb. While we will be first to deliver a human embryonic (stem cell product) into the clinic, with that accomplishment comes a burden of doing it right.”

Human embryonic stem cells can grow into any type of tissue, giving scientists hope of replacing or helping to heal tissues damaged by diseases or injuries. Doctors have used adult stem cells for decades in bone marrow transplants for cancer patients, but embryonic stem cells are considered more versatile in the lab.

In Geron’s case, researchers tapped fertilized embryos that were unused in in-vitro fertilization procedures and destined to be destroyed. Adding chemicals allows the cells to divide naturally, eventually scaling them into thousands of dosages of a drug.

In a video presentation to analysts and investors in New York in November, Geron showed rats with spinal cord injuries that could barely move. Within weeks after they were injected with the stem cell-derived drug known as GRNOPC1, the rodents were seen scurrying around their cages, back legs moving and tails no longer dragging.