First hESC-Derived Therapy Begins in Humans

No longer a fanciful abstraction, the use of hESC-derived cells in humans has begun in a phase 1 clinical trial. The specific hESC-derived cell line, called GRNOPC1 and licensed to the California-based Geron, will be injected into the spinal cords of patients with subacute thoracic injury. The first enrollee got a shot of 2 million hESC-derived oligodendrocytes yesterday at the Shepherd Center in Atlanta. The story is carried by the LA Times, and Geron's press release can be found here.

The company has selected 6 other medical centers for the trial, including the primary site of Northwestern University in Chicago, which is currently open for enrollment. The trick or trickiness of enrolling patients will be to identify individuals who have sustained complete (ie, grade A) spinal injury at the thoracic level (T3-T10) and are within 1-2 weeks of injury onset. However, the anticipated number of enrollees is small: 10.

The human clinical trial represents the expected quantum step from animal studies of GRNOPC1, which demonstrated improved locomotion in spinally injured rats and histologic evidence of cellular function. The development of epithelial cysts at the sites of cord injury in animals stalled a go-ahead from the FDA in 2009 to begin human trials. But the regulatory hold was lifted in July of this year, after Geron performed additional preclinical studies.

Oligodendrocytes, the myelin-producing cells of the central nervous system, are expected to facilitate signal conduction in a damaged cord. However, hESC-derived cells may also express important neurotrophic factors that promote the survival or regeneration of injured axons.

hESC = human embryonic stem cell.

Transverse section of the thoracic spinal cord from Gray's Anatomy (1918).