Embryonic Stem-Cell Therapy Tested on Paraplegic

Geron Corp. has begun testing an embryonic stem-cell treatment on a patient with spinal cord injuries, marking the first time such a medical therapy has been used on a human in a government approved study.

The company said it enrolled the first patient in the early stage study, which will look at the safety of the treatment and how well the patient can tolerate it. The patient was enrolled at Shepherd Center, a spinal cord and brain injury rehabilitation center in Atlanta, one of seven potential sites in the United States. In order to participate, a patient must have been injured within the previous two weeks.

“When we started working with human embryonic stem cells in 1999, many predicted that it would be a number of decades before a cell therapy would be approved for human clinical trials,” Dr. Thomas B. Okarma, Geron’s president and chief executive officer, said in a statement.

While a milestone in the technology, the drug candidate is still a long way from being proven and reaching the market. It still faces many years of testing for effectiveness if all goes well in the early stage study.

Embryonic stem cells have been at the center of funding controversies because the research involves destroying the embryos, which some have argued is akin to abortion. But, many researchers consider embryonic stem cells the most versatile types of stem cells, as they can morph into any type of cell. While federal funding for stem cell lines for research has been challenged in a lawsuit, companies such as Geron do not use government funding.

The company has said it plans to enroll eight to 10 patients in the study at sites nationwide. The trial will take about two years, with each patient being studied for one year. Early stage clinical trials are primarily designed to test a therapy’s safety. A successful safety test would lead to larger and longer studies that would focus on the effectiveness.

The treatment — known as GRNOPC1 — contains cells called oligodendrocyte progenitor cells. Those progenitor cells turn into oligodendrocytes, a type of cell that produces myelin, a coating that allows impulses to move along nerves. If GRNOPC1 works, the progenitor cells will produce new oligodendrocytes in the injured area of the patient’s spine, potentially allowing for new movement.

The therapy will be injected into the patients’ spines one to two weeks after they suffer an injury between their third and 10th thoracic vertebrae, or roughly the middle to upper back. Later trials would include patients with less severe spinal injuries and damage to other parts of the spine.

Geron, based in Menlo Park, Calif., is among several companies focusing on embryonic stem cell therapy as medical treatments. Advanced Cell Technology Inc. hopes to develop the embryonic stem cell therapy called retinal pigment epithelium, or RPE. That therapy is designed to treat Stargart disease, an inherited condition that affects children and can lead to blindness in adulthood.

Meanwhile, other companies such as StemCells Inc. are focusing on adult stem cells, which can be gathered from a person’s skin.

Shares of Geron rose 34 cents, or 6.4 percent, to $5.67 in afternoon trading.

DAMIAN TROISE, AP Health Writer NEW YORK