#1geron Enhancing the Lives of Patients with Hematologic Malignancies Corporate Presentation January 2024 www#2Forward-Looking Statements and Safe Harbor 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 the Company is on target for successful transition to a commercial company in 2024; (ii) plans for approval and a potential launch of imetelstat in TD LR-MDS in the U.S. by the end of the first half of 2024 and for the MAA review to be completed by the end of 2024, with potential EU approval and launch in 2025; (iii) that imetelstat has showed unprecedented durability of transfusion independence across multiple MDS patient subgroups that are not addressed by currently available products, and is a differentiated first-in-class investigational telomerase inhibitor; (iv) that for the Phase 3 IMpactMF in R/R MF, Geron expects to conduct an interim analysis in the first half of 2025 and the final analysis in the first half of 2026, together with the assumptions used in making these estimates; (v) that the Company believes imetelstat has a potential total addressable market (TAM) in the US/EU of greater than $3.5B in TD LR-MDS and greater than $3.5B in R/R MF in 2031; (vi) the status, plans and expected timing of the Company's clinical programs on its pipeline chart; (vii) that imetelstat has the potential to have disease-modifying activity in patients; (viii) the Company's estimates and assumptions used in the calculations of percentages and numbers of patients in the treatment landscape for LR-MDS; (ix) that the Company expects imetelstat to be a highly differentiated product in the TD LR-MDS commercial marketplace; (x) that there are unmet needs in TD LR-MDS and R/R MF potentially addressed with imetelstat treatment; (xi) the Company's market research used to obtain the views of practicing hematologists of the IMerge Phase 3 data and the opportunity in TD LR-MDS patients, including the characteristics of imetelstat and the Phase 3 data that support the expectation that imetelstat can become a compelling treatment option and standard of care with a significant market opportunity; (xii) that the Company is well-positioned for a successful launch of imetelstat, if approved, and the Company's plans and expectations regarding launch preparations; (xiii) the Company's assumptions and expectations regarding the expected opportunity for imetelstat in R/R MF; (xiv) the Company's estimates of cash and marketable securities and operating expenses as of December 31, 2023; (xv) the Company's projections and expectations regarding the sufficiency of its cash resources and expected available resources to fund its projected operating requirements into Q3 2025, and the assumptions underlying such projections and expectations; (xvi) the Company's estimates and assumptions used in the calculations of total addressable market (TAM); and (xvii) 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 FDA and EMA may have issues with the NDA or MAA for imetelstat for TD LR-MDS that delay or prevent approval and a potential commercial launch; (b) whether we will be able to continue to develop imetelstat or advance imetelstat to subsequent clinical trials, or that we will be able to receive regulatory approval for or successfully commercialize imetelstat, on a timely basis or at all; (c) whether imetelstat may cause, or have attributed to it, adverse events that could further delay or prevent the commencement and/or completion of clinical trials, delay or prevent its regulatory approval, or limit its commercial potential; (d) whether the IMpactMF Phase 3 trial for R/R MF has a positive outcome and demonstrates safety and effectiveness to the satisfaction of the FDA and international regulatory authorities, and whether our projected rates for enrollment and death events differ from actual rates, which may cause the interim and final analyses to occur later than anticipated; (e) whether we overcome all of 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; (f) if imetelstat is approved for marketing and commercialization, whether we are able to establish and maintain effective sales, marketing and distribution capabilities, obtain adequate coverage and third-party payor reimbursement, and achieve adequate acceptance in the marketplace; (g) whether imetelstat actually demonstrates disease-modifying activity in patients; (h) whether there are failures in manufacturing or supplying sufficient quantities of imetelstat that would delay, or not permit, the anticipated commercial launch or not enable ongoing or planned clinical trials; (i) whether we are able to obtain and maintain the exclusivity terms and scopes provided by patent and patent term extensions, regulatory exclusivity, and have freedom to operate; (j) that we may be unable to successfully commercialize imetelstat due to competitive products, or otherwise; (k) that we may decide to partner and not to commercialize independently in the U.S. or in Europe and other international markets; (I) whether we have sufficient resources to satisfy our debt service obligations and to fund our planned operations; (m) that we may seek to raise substantial additional capital in order to complete the development and commercialization of imetelstat and to meet all of the expected timelines and planned milestones, and that we may have difficulty in or be unable to do so; and (n) the impact of general economic, industry or political climate in the U.S. or internationally and the effects of macroeconomic conditions on our business and business prospects, financial condition and results of operations. 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 under the heading "Risk Factors" or other similar headings found in documents Geron files from time to time with the Securities and Exchange Commission (the "SEC"), including the Company's Report on Form 10-Q for the quarter ended September 30, 2023 and subsequent filings. Undue reliance should not be placed on forward-looking statements, which speak only as of the date they are ma 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. geron 2#3Geron is On Target for a Successful Transition to Commercial Company in 2024 ↑ili↑ PDUFA date of June 16, 2024 for imetelstat in transfusion-dependent (TD) LR-MDS* MAA review completion expected by end-2024, with potential EU approval and launch in 2025 `O- 0-0 geron Imetelstat Ph3 data showed unprecedented durability of transfusion independence (TI) across multiple MDS patient subgroups not addressed by currently available products Additional Ph3 trial of imetelstat ongoing in relapsed/refractory myelofibrosis (R/R MF) with an interim analysis expected first half of 2025 Significant commercial opportunities with TD LR-MDS total addressable market (TAM) >$3.5B and R/R MF TAM >$3.5B in 2031 (U.S./EU)^ *Imetelstat is currently under regulatory review by FDA and EMA for the treatment of transfusion-dependent anemia in adult patients with low- to intermediate-1 risk myelodysplastic syndromes (LR- MDS) who have failed to respond or have lost response to or are ineligible for erythropoiesis-stimulating agents (ESAS). Platzbecker, Santini et al. The Lancet 2023 ^see slide 33 for more information on TAM and patient numbers 3#4Exploring the Broad Potential of Imetelstat and Telomerase Inhibition Indications TD LR-MDS Single Agent R/R MF Single Agent Frontline MF Combination Therapy R/R AML & HR MDS Single Agent R/R AML Combination Therapy Lymphoid Malignancies Next Generation TI Program geron Discovery Ongoing; Company Sponsored Preclinical Phase 1 IMproveMF TELOMERE Leads identified; optimization ongoing Phase 2 Ongoing; Investigator Led IMpress Phase 3 Experiments ongoing IMerge Escalated to second dose cohort Oct. 2023 IMpactMF To follow single agent data from Impress U.S. PDUFA: June 16, 2024 EU MAA under review First patient dosed Jun. 2023 Planned; Investigator Led Interim Analysis est.: 1H 2025 Final Analysis est.: 1H 2026 TD LR-MDS: transfusion-dependent lower-risk myelodysplastic syndromes; R/R MF: relapsed/refractory myelofibrosis; MF: myelofibrosis; R/R AML: relapsed/refractory acute myeloid leukemia; HR MDS: higher risk myelodysplastic syndromes; Tl: telomerase inhibitor; PDUFA: Prescription Drug User Fee Act; MAA: marketing authorization application#5Imetelstat is a First-in-Class Telomerase Inhibitor Based on Nobel-Prize Winning Science Potentially powerful mechanism for treating hematologic malignancies Telomerase is continually upregulated in malignant cells Malignant clones geron Imetelstat binds to telomerase, inhibiting its activity Upregulated telomerase Telomerase ✓ Jua Imetelstat Apoptosis of malignant cells and recovery of effective hematopoiesis Apoptotic malignant clones 8888 Imetelstat is designed to target malignant clones at their source and enable recovery of healthy blood cell production Inhibition of telomerase Murati et al, BMC Cancer 2012; Shih et al, Rev Cancer 2012; Ntziachristos et al, Adv Immunol 2013; Vardiman et al, Blood 2009; Kittur et al, Cancer 2007; Anastasi J Hematol Oncol Clin North Am. 2009; Hiyama et al. J Immunol 1995; Hiyama et al, Br J Cancer 2007; Bruedigam et al, Cell Stem Cell 2014: Mosoyan et al, Leukemia 2017; Wang et al, Blood Adv 2018; Steensma et al, JCO 2020; Platzbecker et al, ASH 2020; Mascarenhas et al, JCO 2021; Mascarenhas et al, ASH 2018 and 2020 and EHA 2021; Platzbecker, Santini et al, The Lancet 2023. Evidence for potential disease modification Clinical efficacy: durable TI (TD LR- MDS Ph3); improved overall survival (R/R MF Ph2) Molecular data: reductions in variant allele frequency (VAF) and depletion of mutated abnormal cells associated with disease 5#6geron Transfusion-Dependent Lower-Risk MDS PDUFA date of June 16, 2024* *Imetelstat is currently under regulatory review in the U.S. and EU for the treatment of transfusion-dependent anemia in adult patients with low- to intermediate- 1 risk myelodysplastic syndromes (MDS) who have failed to respond or have lost response to or are ineligible for erythropoiesis-stimulating agents (ESAs). 6#7Lower-Risk MDS Patient Experience B Diagnosis Median age ~70 years Symptomatic Anemia geron Increasing Transfusion Dependence Lengthy Office Visits High-Cost Burden Symptomatic anemia and transfusion dependence are key drivers of patient burden and poor quality of life Poor Quality of Life Higher Risk of Progression to AML DRG MDS Landscape & Forecast 2022, Mangaonkar, et al., Blood Cancer Journal 2018; Giagounidis, et al. Clinical Cancer Research 2016; Incidence and Outcomes for Low Risk MDS, ASH 2012; Greenberg et al, Blood 2012; Feneaux et al, JCO 2017; Platzbecker et al, Blood 2019; Cogle et al, Curr Hematol Malig Rep 2015; Greenberg et al Blood 1997; Greenberg et al, Blood 1997. Shortened Survival 7#8Treatment Landscape for LR-MDS Continuing unmet need presents significant opportunity for imetelstat; ~$3.5B TAM in 2031 (U.S./EU)^ HR MDS 1st line NCCN Guidelines (updated Oct. 2023) geron Complex presentations ↓ Lower Risk MDS (~70%) RS+ (~25%) Luspatercept ↓ Symptomatic Anemia (~90%) SEPO (>500 mU/mL) (-10%) ↓ RS-(-75%) ESAS - preferred Luspatercept - other recommended ↓ ↓ Second line & later RS+/RS- SEPO (>500 mU/mL) (-10%) ESAS and luspatercept are among the agents approved in this first-line setting. Clinical trials preferred. Other options include HMAS and immunosuppressive drugs Adapted from LR MDS NCCN Guidelines Oct 2023; Ring sideroblasts present in ~23%-33% of patients with MDS and are associated with anemia (references: 2. Papaemmanuil E, Gerstung M, Malcovati L, et al. Clinical and biological implications of driver mutations in myelodysplastic syndromes. Blood. 2013;122 (22):3616-3627. 3. Malcovati L, Cazzola M. Recent advances in the understanding of myelodysplastic syndromes with ring sideroblasts. Br J Haematol. 2016;174(6):847-858. ^see slide 33 for more information on TAM and patient numbers Significant potential opportunity for imetelstat: Frontline ESA ineligible (~4k)^ ESA-failed, RS+ (~8k)^ ESA-failed, RS-(~24k)^#9Differentiated Imetelstat Profile in IMerge Phase 3 40% ≥ 8-wk RBC-TI response rate; 1-year median 3.6 g/dL median Hgb rise TI duration Robust & Durable Response 18% ≥ 1-yr RBC-TI response rate; 5.2 g/dL median Hgb rise 60% transfusion reduction by ≥4U/8 wks; 1.4 g/dL median Hgb rise RS+ and RS- geron 2.4 years median TI duration Broad Response Across MDS Subgroups High and very high transfusion burden 1.3 years duration SEPO level greater than or less than 500 mU/mL Platzbecker, Santini et al. The Lancet 2023 Additional IMerge data including placebo comparisons included on slides 10-17 Low or intermediate-1 IPSS risk category SSS IDA IMerge Additional Attributes 50% of imetelstat-treated patients reported less fatigue (PRO data) ≥50% VAF reduction in commonly mutated MDS genes experienced by more imetelstat-treated patients vs placebo Well Characterized Safety Profile the most common adverse events were thrombocytopenia and neutropenia that were manageable and of short duration 9