Geron Presents Data From GRNOPC1 Trial at International Conferences on Spinal Cord Medicine and Rehabilitation

June 7, 2011

MENLO PARK, Calif., June 7, 2011 - Geron Corporation (Nasdaq: GERN) today announced two presentations on the company's ongoing Phase 1 clinical trial of the human embryonic stem cell-based therapy, GRNOPC1, in patients with spinal cord injury. Data on the first two patients were presented at the 2011 International Conference on Spinal Cord Medicine and Rehabilitation in Washington, D.C. A second presentation was given at the 2011 Spine Symposium, which was held as part of The American Spinal Injury Association (ASIA) Annual Scientific Meeting. The presentations were given by Edward Wirth, III, M.D., Ph.D., Geron's Medical Director for Cell Therapies and Linda Jones, P.T., M.S., Geron's Senior Clinical Trials Manager for GRNOPC1.

"We are pleased to report a very good safety profile of GRNOPC1 to date, with no serious adverse events," said Dr. Wirth. "Currently, we have two patients in the trial. We anticipate increased enrollment going forward as we open our additional clinical sites and following FDA approval to expand our inclusion criteria to patients with injuries resulting in a neurological level of T11, which represents a substantial percentage of thoracic injuries, and to reduce the stagger between patients from 30 days to 10 days."

Phase 1 Clinical Trial Data

Data were presented on two patients with neurologically complete American Spinal Injury Association (ASIA) Impairment Scale grade A thoracic spinal cord injuries, who received GRNOPC1 at a dose of 2 million cells delivered by injection into the lesion site using a syringe positioning device specially 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given for temporary immune-suppression from the time of injection for 46 days, at which point the dose was tapered and withdrawn completely at 60 days.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 neurological function, using standardized testing at specified timepoints to monitor sensory and lower extremity motor function. The trial protocol also includes multiple MRI scans. One patient in the trial has completed the Day 180 follow-up visit and the other has completed Day 7 follow-up.

There were no surgical complications during or after either procedure. No adverse events have occurred to date related to the injection procedures or to GRNOPC1. One patient experienced two mild adverse events related to tacrolimus, nausea and low magnesium, which are known to be associated with the immune-suppressive drug and were minor. There is no evidence of cavitation in the spinal cord at the injury site on MRI through Day 180. Initial analyses have shown no evidence of immune responses to GRNOPC1 through Day 90, which includes 30 days after complete withdrawal of immune-suppression.

Regulatory & Operational Update

The company has received clearance from the FDA to expand eligibility criteria from injuries between spinal segments T3 and T10 to include patients with injuries at T11. In addition, the FDA has approved that the current 30 day period between subjects in the trial may be reduced to 10 days.

Five clinical sites are currently open for patient enrollment, with two additional sites to follow. All sites are referral medical centers for spinal cord trauma and/or rehabilitation, and the catchment area for the clinical trial now includes all 48 lower U.S. States.

GRNOPC1 Clinical Program

In this first cohort of patients, a dose of 2 million cells is being administered to assess safety in up to 10 patients with neurologically complete injuries in the thoracic region of the spinal cord. Pending demonstration of safety in that patient population, clinical testing will be expanded to patients with injuries to the cervical region and to patients with neurologically incomplete injuries, as well as to assess escalating doses of GRNOPC1.

Program Funding

In May, Geron announced a Targeted Clinical Development Award totaling $25 million from the California Institute for Regenerative Medicine (CIRM) to support the clinical development of GRNOPC1. The Award will support funding of clinical trial costs, related non-clinical studies, analytical development and the manufacture of cells to be used in the clinical trial. CIRM funding will provide matching support as Geron progresses the Phase 1 clinical program in spinal cord injury.

About GRNOPC1

GRNOPC1 contains hESC-derived oligodendrocyte progenitor cells that have demonstrated remyelinating, nerve growth stimulating and angiogenic properties leading to restoration of function in animal models of acute spinal cord injury. Preclinical studies have shown that administration of GRNOPC1 significantly improved locomotor activity and kinematic scores of animals with spinal cord injuries when injected seven days after the injury. Histological examination of the injured spinal cords treated with GRNOPC1 showed improved axon survival and extensive remyelination surrounding the rat axons. A Phase 1 clinical trial of GRNOPC1 has been initiated in patients with complete ASIA Impairment Scale grade A thoracic spinal cord injuries. For more information about GRNOPC1, visit www.geron.com/GRNOPC1Trial. For further information about the Phase 1 clinical trial, including location of clinical sites, visit www.clinicaltrials.gov/ct2/show/NCT01217008.

About Spinal Cord Injury

Spinal cord injury is caused by trauma to the spinal cord that results in a loss of motor control, sensatory perception or bowel and bladder control. A traumatic blow to the spine can fracture or dislocate vertebrae that may cause bone fragments or disc material to injure the nerve fibers and damage the oligodendrocyte cells that insulate the nerve fibers in the spinal cord. Most human spinal cord injuries are contusions (bruises) to the cord, rather than a severance of the nerve fibers. Every year approximately 12,000 people in the U.S. sustain spinal cord injuries. There are currently no approved therapies for the treatment of spinal cord injury.

About Geron

Geron is developing first-in-class biopharmaceuticals for the treatment of cancer and chronic degenerative diseases. The company is advancing anti-cancer therapies through multiple Phase 2 clinical trials in different cancers by targeting the enzyme telomerase and with a compound designed to penetrate the blood-brain barrier. The company is developing cell therapies from differentiated human embryonic stem cells for a range of indications, with the first product in a Phase 1 clinical trial for spinal cord injury. For more information, visit www.geron.com.

This news release may contain forward-looking statements made pursuant to the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Investors are cautioned that statements in this press release regarding potential applications of Geron's human embryonic stem cell technologies and GRNOPC1 constitute forward-looking statements that involve risks and uncertainties, including, without limitation, risks inherent in the development and commercialization of potential products, uncertainty of clinical trial results or regulatory approvals or clearances, need for future capital, dependence upon collaborators and protection of our intellectual property rights. Actual results may differ materially from the results anticipated in these forward-looking statements. Additional information on potential factors that could affect our results and other risks and uncertainties are detailed from time to time in Geron's periodic reports, filed with the Securities and Exchange Commission, including the quarterly report on Form 10-Q for the quarter ended March 31, 2011.

CONTACT:

Anna Krassowska, Ph.D.
Investor and Media Relations
650-473-7765
info@geron.com

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