of Geron Corporation, dated

Press Release of Geron Corporation, dated

GERON CORPORATION ANNOUNCES WARRANT EXCHANGE

MENLO PARK, Calif., January 15,

2010 - Geron Corporation

(Nasdaq: GERN) today announced that it has entered into an agreement to exchange

outstanding warrants held by certain institutional investors for shares of Geron

common stock. In connection with the exchange, the company sold additional

shares of common stock to the investors at a premium for gross proceeds of $10.0

million, and issued a call option to the investors to purchase an additional

$5.0 million of common stock at the premium price.

investors will deliver warrants to purchase approximately 5.6 million shares of

common stock for cancellation in exchange for the issuance by the company of 2.7

million shares of its common stock. The same investors will purchase 1.5 million

shares of common stock at an 8% premium to market, or $6.75 per share. The

purchase includes a call option to acquire an additional $5.0 million of common

stock at the premium price. The option expires on October 31, 2010. A number of

shares equal to those issued in exchange for the outstanding warrants cannot be

sold during the 12 month period from the date of issuance unless the sales are

at prices in excess of $9.11 per share.

"This exchange accounts

for approximately three-quarters of all outstanding warrants," said David L.

Greenwood, Geron's executive vice president and chief financial officer. "2.7

million shares are subject to a lock-up provision, and the new block of shares

being purchased at a premium strengthens the balance sheet and provides

additional capital to fund clinical trials."

The shares to be issued

in exchange for the cancellation of outstanding warrants, the newly purchased

shares, the call option and the shares underlying the call option were offered

through a prospectus supplement to the company's effective universal shelf

registration statement (File No. 333-160498). The company arranged the financing

directly with the investors.

first-in-class biopharmaceuticals for the treatment of cancer and chronic

degenerative diseases, including spinal cord injury, heart failure and diabetes.

The company is advancing an anti-cancer drug and a cancer vaccine that target

the enzyme telomerase through multiple clinical trials in different cancers. 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 Geron's financial position

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 maintenance 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, including the quarterly report on Form

10-Q for the quarter ended September 30, 2009.

Anna Krassowska, Ph.D.

Investor and Media Relations