Press Release Dated

Press Release Dated March 12, 2013

Geron Corporation Reports Fourth

Quarter and Annual 2012 Financial Results

MENLO PARK, Calif., March 12,

2013 Geron Corporation (Nasdaq: GERN) today

reported financial results for the fourth quarter and year ended December 31,

Fourth Quarter 2012 Results

Net loss for the fourth quarter of 2012

was $15.9 million, or $0.12 per share, compared to $31.9 million, or $0.25 per

share, for the comparable 2011 period. Net loss for the fourth quarter of 2012

and 2011 included restructuring charges of $2.7 million and $5.4 million related

to the discontinuation of the company s GRN1005 and stem cell programs,

respectively. Net loss for the fourth quarter of 2011 also included non-cash

debt extinguishment charges of $1.7 million resulting from the repayment of the

loan to the California Institute for Regenerative Medicine. The company ended

2012 with $96.3 million in cash and investments.

In the fourth quarter of 2012, the company

had revenues of $689,000, compared to $251,000 for the comparable 2011 period.

Revenues in both periods primarily reflected license fees and

Interest and other income for the fourth

quarter of 2012 was $2.6 million, compared to $204,000 for the comparable 2011

period. In December 2012, the company received $2.5 million in other income in

connection with the assignment of certain intellectual property related to the

company s telomerase activation technology.

In the fourth quarter of 2012, the company

had operating expenses of $19.2 million, compared to $30.7 million for the

comparable 2011 period. Research and development expenses for the fourth quarter

of 2012 were $11.8 million, compared to $19.7 million for the comparable 2011

period. The decrease in research and development expenses primarily was due to

reduced scientific supply costs and personnel-related costs as a result of the

discontinuation of the company s stem cell programs and reduced costs for the

manufacturing of imetelstat drug product resulting from the timing of

manufacturing campaigns. General and administrative expenses for the fourth

quarter of 2012 were $4.7 million, compared to $5.5 million for the comparable

2011 period. The decrease primarily was due to lower non-cash stock-based

compensation expense.

Non-cash operating expenses for the fourth

quarter of 2012 were approximately $2.7 million, which primarily included

stock-based compensation, write-downs of excess lab equipment related to the

GRN1005 program and expense for stock issued for services. Non-cash operating

expenses for the fourth quarter of 2011 were approximately $6.0 million, which

primarily included stock-based compensation, write-downs of excess lab equipment

related to the company s stem cell programs and expense for stock issued for

Year-End 2012 Results

For 2012, net loss was $68.9 million, or

$0.54 per share, which included restructuring charges of $2.7 million, compared

to $96.9 million, or $0.78 per share, for 2011, which included restructuring

charges of $5.4 million and non-cash debt extinguishment charges of $1.7

Revenues for 2012 and 2011 were $2.7

million and $2.4 million, respectively, reflecting funding under a collaborative

agreement and license fees and royalties.

For 2012, interest and other income was

$3.1 million, which included the receipt of $2.5 million for the assignment of

the company s telomerase activation technology. Interest and other income was

$1.0 million for 2011.

For 2012, the company had operating

expenses of $74.5 million, compared to $98.6 million for 2011. Research and

development expenses for 2012 were $51.4 million, compared to $69.3 million for

2011. Overall, research and development expenses decreased in 2012 as a net

result of reduced scientific supply costs and personnel-related costs due to the

discontinuation of the company s stem cell programs and reduced costs for the

manufacturing of imetelstat drug product resulting from the timing of

manufacturing campaigns, partially offset by higher costs for the company s

GRN1005 program. General and administrative expenses for 2012 were $20.4

million, compared to $23.8 million for 2011. The decrease was primarily the net

result of lower non-cash stock-based compensation expense, partially offset by

increased legal and consulting costs associated with the company s intellectual

property portfolio and the divestiture of the company s stem cell

Page Two / Geron Corporation Reports

Fourth Quarter and Annual 2012 Financial Results

Non-cash operating expenses for 2012 were

approximately $9.1 million, which primarily included stock-based compensation,

depreciation, write-downs of excess lab equipment related to the GRN1005 program

and expense for stock issued for services. Non-cash operating expenses for 2011

were approximately $25.2 million, which primarily included stock-based

compensation, depreciation, write-downs of excess lab equipment related to the

company s stem cell programs and expense for stock issued for

Clinical Development

In December 2012, Geron reported

positive clinical results from the Phase 2 trial of imetelstat, the company's

first-in-class telomerase inhibitor, in patients with essential

thrombocythemia (ET) who did not respond to or tolerate other therapies. ET is

a chronic blood disorder that is representative of a group of diseases known

as myeloproliferative neoplasms. The data, which showed durable hematologic

and molecular responses in patients treated with imetelstat, suggest a

relatively selective activity of imetelstat against the malignant progenitors

driving ET, and provide evidence to support a potential disease-modifying

effect. These findings were presented in an oral session at the 54th Annual

Meeting of the American Society of Hematology in Atlanta, GA, by Prof. Dr.

med. Gabriela M. Baerlocher of the University Hospital and University of Bern,

Switzerland, and a principal investigator of the trial.

The Phase 2 trial of imetelstat in ET was designed to

provide proof-of-concept for the potential use of the drug as a treatment for

hematologic myeloid malignancies, including myelofibrosis, myelodysplastic

syndromes and acute myelogenous leukemias. Based on the results from the ET

trial, Dr. Ayalew Tefferi at the Mayo Clinic has begun an

investigator-sponsored trial (IST) to evaluate the safety and efficacy of

imetelstat in patients with myelofibrosis and determine the optimal dose and

schedule for further evaluation. Geron is in the initial planning stages of a

company-sponsored trial in myelofibrosis, which will be informed by data from