Geron Corporation has made a cell line called GRNOPC1 from embryonic stem cells. GRNOPC1 is an “oligodendrocyte precursor cell” or OPC line. Before you blow a gasket at the sight of such a long-winded description, just remember that nerves are like wires and wires need insulation.  OPCs are the cells that make the insulation.  During spinal cord injury, the insulation dies off and it causes nerves to malfunction.

In collaboration with Hans Keirstead at UC Irvine, Geron developed a protocol for the administration of GRNOPC1 cells to animals with acute spinal cord injuries. His protocol showed that the OPCs were safe (no tumors were seen, even after one year) and somewhat effective. Some scientists were skeptical, since the mice had somewhat less severe spinal cord injuries.  Nevertheless, Geron was granted an Investigational New Drug Application from the FDA to conduct a Phase I trial with their OPC cell line.

They apparently, however, have bit a bit of a snag. Here is a press release from Geron Corporation.

Geron Corporation today announced that its IND (Investigational New Drug application) for GRNOPC1, a cell therapy for neurologically complete, subacute spinal cord injury, has been placed on clinical hold by the FDA pending the agency’s review of new nonclinical animal study data submitted by the company. A clinical hold is an order that the FDA issues to a sponsor to delay a proposed trial or to suspend an ongoing trial.

Since filing the IND, Geron has been undertaking studies to enable dose escalation of its spinal cord injury product, and has been investigating application of the product to other neurodegenerative diseases. The company has also been performing additional product characterization and conducting further animal studies. Data from this work has been submitted to the FDA. Geron will work closely with the FDA to facilitate their review of the new data and to release the clinical hold. No patients have yet been treated in this study.

From the sound of it, this hold is merely an administrative procedure that the FDA routinely undergoes when presented with new data.  However, if the new data is completely consonant with previous findings, why would there be a hold? We simply do not know at this time.  It is entirely possible that nothing is amiss, and this is merely FDA policy.  However, it is also possible that Geron’s new product does not behave exactly as they thought.

The development of the first cholesterol-lowering drug (lovastatin) experienced a slow-down when a related product being developed in Japan caused cancer in dogs. Roy Vagelos, president of Merck at the time, contacted the FDA and suspended all clinical trials. Further testing by Merck showed that this was an anomaly, and extensive clinical use has vindicated this finding. Maybe this is a similar situation for Geron’s OPC line?  Only time will tell.


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Professor of Biochemistry at Spring Arbor University (SAU) in Spring Arbor, MI. Have been at SAU since 1999. Author of The Stem Cell Epistles. Before that I was a postdoctoral research fellow at the University of Pennsylvania in Philadelphia, PA (1997-1999), and Sussex University, Falmer, UK (1994-1997). I studied Cell and Developmental Biology at UC Irvine (PhD 1994), and Microbiology at UC Davis (MA 1986, BS 1984).