Geron : 2022 H.C. Wainwright 24th Annual Global Investment Conference

CHANGING THE COURSE OF HEME MALIGNANCIES

CORPORATE PRESENTATION

John A. Scarlett, M.D.

Chairman and Chief Executive Officer

H.C. Wainwright 24th Annual Global Investment Conference September 13, 2022

Forward-Looking Statements

Except for the historical information contained herein, this presentation contains forward-looking statements made pursuant to the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Investors are cautioned that such statements, include, without limitation, those regarding: (i) that for IMerge Phase 3, Geron expects top-line results to be available in early January 2023, regulatory filings in the U.S. in the first half of 2023 and the EU in the second half of 2023, and a potential launch in lower risk MDS in the U.S. in the first half of 2024 and in the EU in the second half of 2024; (ii) that for IMpactMF, Geron expects to conduct an interim analysis in 2024 and a final analysis in 2025; (iii) that for the next generation telomerase inhibitor program, Geron plans to make a program update in 2022 when and if Geron identifies a lead compound and IND timing is known; (iv) that Geron expects current and potential financial resources provide strategic optionality to maximize shareholder value; (v) that Geron plans to engage over 180 sites for IMpactMF; (vi) that IMerge Phase 3 and IMpactMF have registrational intent; (vii) that imetelstat has the potential to demonstrate disease-modifying activity in patients and to target the malignant stem and progenitor cells of the underlying disease; (viii) that the Company expects imetelstat to be a highly differentiated product in the lower risk MDS commercial marketplace; (ix) that the Company projects that the addressable patients in 2030 for imetelstat in LR MDS are approximately 33,000 and for Int-2/HR MF are approximately 18,000; (x) that the Company believes imetelstat has potential billion dollar market opportunities with potential peak 2030 revenue from the United States and the five largest countries of the European Union (EU5) of approximately $3 billion; (xi) that there are unmet needs in LR MDS and MF potentially addressed with imetelstat treatment;

1. that the telomerase inhibition of imetelstat gives it the potential for expanding into new indications; (xiii) that the Company believes the IMproveMF Phase 1 study will allow the Company to potentially demonstrate safety and efficacy of combination therapy with imetelstat and ruxolitinib in the frontline MF setting as well as explore the potential for disease modification with imetelstat earlier in MF disease setting; (xiv) that the Company expects IMpress to start in the second half of 2022; (xv) that the study start for TELOMERE is pending IMpress single-agent data; (xvi) that the Company expects initial data from the preclinical program in lymphoid malignancies to be available at the end of 2022; (xvii) that projected financial resources are believed to be sufficient to support operations through the middle of 2024, from approximately $130 million in expected cash and marketable securities as of early January 2023 and up to approximately $174 million in financial resources (consisting of up to $124 million from the potential exercise of currently outstanding warrants and potential debt drawdowns of up to $50 million subject to meeting certain milestone and capitalization requirements); and (xviii) other statements that are not historical facts, constitute forward-looking statements. These forward-looking statements involve risks and uncertainties that can cause actual results to differ materially from those in such forward-looking statements. These risks and uncertainties, include, without limitation, risks and uncertainties related to: (a) whether the current or evolving effects of the COVID-19 pandemic and/or geopolitical events and resulting global economic and financial disruptions will materially and adversely impact Geron's business and business prospects, its financial condition and the future of imetelstat; (b) whether Geron overcomes all of the potential delays and other adverse impacts caused by the current or evolving effects of the COVID-19 pandemic and/or geopolitical events, as well as all the enrollment, clinical, safety, efficacy, technical, scientific, intellectual property, manufacturing and regulatory challenges in order to have the financial resources for, and to meet the expected timelines and planned milestones in (i) to (iii),(v) and (xiii) to (xvi) above; (c) whether regulatory authorities permit the further development of imetelstat on a timely basis, or at all, without any clinical holds; (d) whether imetelstat is demonstrated to be safe and efficacious in IMerge Phase 3 and IMpactMF to enable regulatory approval; (e) whether any future efficacy or safety results may cause the benefit-risk profile of imetelstat to become unacceptable; (f) whether imetelstat actually demonstrates disease-modifying activity in patients and the ability to target the malignant stem and progenitor cells of the underlying disease; (g) that Geron may seek to raise substantial additional capital in order to complete the development and commercialization of imetelstat to meet all of the expected timelines and planned milestones in (i) to (iii), (v) and (xiii) to (xvi) above; (h) whether regulatory authorities require an additional clinical trial for approval even if IMerge Phase 3 or IMpactMF meet their respective primary endpoints; (i) whether there are failures or delays in manufacturing or supplying sufficient quantities of imetelstat or other clinical trial materials in a timely manner; (j) whether imetelstat is able to obtain and maintain the exclusivity terms and scopes provided by patent and patent term extensions, orphan drug, data and marketing and pediatric coverages and have freedom to operate; (k) whether the follow-up period of 12 months for the IMerge Phase 3 primary analysis results in not obtaining adequate data to demonstrate safety and efficacy, including transfusion independence, in the primary analysis; (l) whether Geron can accurately project the timing of complete enrollment in its, or in the investigator-led clinical trials, whether due to the current or evolving effects of the COVID-19 pandemic or otherwise; (m) whether Geron is able to enroll its clinical trials at a pace that would enable the financial resources for, and to meet the expected timelines and planned milestones in (i) to (iii), (v) and (xiii) to (xvi) above; (n) that Geron may be unable to successfully commercialize imetelstat to achieve the peak revenues in (x) above due to: competitive products, Geron's sales/ marketing and reimbursement efforts not meeting expectations, Geron's decision not to commercialize independently in the EU5, or otherwise; and (o) if the FDA does not grant priority review to the IMerge NDA, then the U.S. launch date in lower risk MDS may be later than the first half of 2024. Additional information on the above risks and uncertainties and additional risks, uncertainties and factors that could cause actual results to differ materially from those in the forward-looking statements are contained in Geron's filings and periodic reports filed with the Securities and Exchange Commission under the heading "Risk Factors" and elsewhere in such filings and reports, including Geron's quarterly report on Form 10-Q for the quarter ended June 30, 2022 and future filings and reports by Geron. Undue reliance should not be placed on forward-looking statements, which speak only as of the date they are made, and the facts and assumptions underlying the forward-looking statements may change. Except as required by law, Geron disclaims any obligation to update these forward-looking statements to reflect future information, events or circumstances.

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Changing the Course of Heme Malignancies with First-in-Class Telomerase Inhibitor

Solid financial

position

Experienced management team

Compelling

Phase 2 data

Novel imetelstat MOA with disease - modifying potential

Heritage in telomerase science

MOA, mechanism of action

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Upcoming pivotal

Phase 3 results

Multi-billion dollar

market opportunities

Building a

commercial company

References on slide 30

Exploring the Broad Potential of Imetelstat and Telomerase Inhibition

Indications

Discovery Preclinical

Phase 1

Phase 2

Phase 3

Expected Milestones

LR MDS

Top-line results:

IMerge

Single agent

Early Jan 2023

Refractory MF

Interim analysis: 2024

IMpactMF

Single agent

Final analysis: 2025

Frontline MF

IMproveMF

Study started: May 2022

Combination therapy

R/R AML & HR MDS

IMpress

Study start: 2H 2022

Single agent

R/R AML

Study start:

TELOMERE

Combination therapy

Pending IMpress data

Lymphoid

Initial data:

Malignancies

Year end 2022

Next Generation TI

Program update: 2022

Program

Ongoing; Company Sponsored

Planned; Investigator Led

LR MDS, lower risk myelodysplastic syndromes; MF, myelofibrosis; R/R AML, relapsed/refractory acute myeloid leukemia; HR MDS, higher risk myelodysplastic syndromes; TI, telomerase inhibitor

4 See Appendix 2 for Phase 3 trial design details

See Appendix 3 for pipeline expansion program details

Anticipated Momentum

Early Jan

2023

IMerge Ph3

top-line results

1H 2023

LR MDS

NDA submission

2H 2023

LR MDS

MAA submission

1H 2024

LR MDS

U.S. approval &

commercial launch

2H 2024

LR MDS

EU approval &

commercial launch

2024

IMpactMF Ph3 interim analysis

LR MDS, lower risk myelodysplastic syndromes; NDA, new drug application, MAA, marketing authorization application

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