Geron announces data from ongoing GRNOPC1 Phase 1 trial on spinal cord injury

Geron Corporation (Nasdaq: GERN) today announced two presentations on the company's ongoing Phase 1 clinical trial of its human embryonic stem cell-based therapy, GRNOPC1, in patients with spinal cord injury. Safety data were presented at the Pre-Conference Symposia of the joint 2011 American Congress of Rehabilitation Medicine and American Society of Neuro-Radiology Annual Meeting in Atlanta, GA. A second presentation was given at the Working 2 Walk 2011 conference in Rockville, MD. The presentations were given by Joseph Gold, Ph.D., Geron's Senior Director of Neurobiology and Stem Cell Therapies and Linda Jones, P.T., M.S., Geron's Senior Clinical Trials Manager for GRNOPC1.

"We are pleased to report that the lowest intended dose of GRNOPC1 has been administered to four patients with complete thoracic spinal cord injuries," said Stephen M. Kelsey, M.D., Geron's Head of Research & Development and Chief Medical Officer. "To date, GRNOPC1 has been well tolerated with no serious adverse events."

Phase 1 Clinical Trial Data

Data were presented on four patients with neurologically complete American Spinal Injury Association (ASIA) Impairment Scale grade A thoracic spinal cord injuries, who received GRNOPC1 at a dose of two million cells delivered by injection into the lesion site using a syringe positioning device designed by Geron. GRNOPC1 was administered between 7 and 14 days after injury. Low-dose tacrolimus was given for temporary immune-suppression from the time of injection for 46 days, at which point the dose was tapered and withdrawn completely at 60 days.

Endpoints of the trial are safety and evaluation of neurological function, using standardized testing at specified timepoints to monitor sensory and lower extremity motor function. The trial protocol also includes multiple MRI scans. Initial follow-up of patients is one year. One patient in the trial has completed the Day 365 follow-up visit. The most recent patient to be enrolled in the clinical trial has completed the Day 30 follow-up. After one year the patients enter a period of long-term follow-up that includes annual in-person visits for the first five years and subsequent yearly check-ups via telephone for an additional nine years.

Safety data to date from the trial has shown:

• No surgical complications during or after the procedures.
• No adverse events related to the injection procedures or to GRNOPC1.
• A few mild adverse events related to tacrolimus.
• No evidence of cavitation in the spinal cord at the injury sites on MRI.
• No unexpected neurological changes.
• No evidence of immune responses to GRNOPC1.

GRNOPC1 was delivered to four spinal cord injured patients at a dose of two million cells without complications from either the cells or the surgical procedure itself, and without any negative effects on the spinal cord or neurological function of the patients to date. The only side-effects observed were due to the immunosuppressive drug tacrolimus, which is administered for the first two months after injection of GRNOPC1. Furthermore, there is no evidence to date of immune rejection of GRNOPC1, an allogeneic cell therapy, including after withdrawal of immunosuppressive drug.