Post-EHA KOL Event June 25, 2019 Forward-Looking Statements Except - PowerPoint PPT Presentation

Post-EHA KOL Event June 25, 2019

Forward-Looking Statements Except for the historical information contained herein, this presentation contains forward-looking statements made pursuant to t he “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 Phase 3 portion of IMerge will be open for patient screening and enrollment in August 2019, with site initiation in July 2019; (ii) that statistical analyses of IMbark data and closely matched RWD suggest favorable overall survival with imetelstat treatment when compared to closely matched RWD from patients treated with BAT in relapsed/refractory MF; (iii) that statistical analyses of IMbark data and closely matched RWD suggest treatment with imetelstat is associated with a lower risk of death compared to BAT; (iv) that imetelstat in lower risk MDS has potential impact on the malignant clone; (v) that imetelstat may have disease-modifying activity; (vi) that there will be an End of Phase 2 meeting with the FDA by the end of Q1 2020; and (vii) other statements that are not historical facts, constitute forward- looking statements. These 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 imetelstat is able to actually demonstrate a lower risk of death and favorable overall survival compared to BAT in relapsed/refractory MF patients; (b) whether the comparative analyses between RWD and IMbark clinical trial data described in the poster presentation at EHA have limitations and cannot be relied upon as demonstrative; (c) whether the Company overcomes all the clinical, safety and efficacy, technical, scientific, manufacturing and regulatory challenges to enable the opening of the Phase 3 portion of IMerge for screening and enrollment in August 2019 and site initiation in July 2019; (d) whether regulatory authorities permit the further development of imetelstat on a timely basis, or at all, without any clinical holds; (e) whether imetelstat is safe and efficacious; (f) whether any future efficacy or safety results may cause the benefit-risk profile of imetelstat to become unacceptable; (g) whether the Company will be able to successfully retain or recruit key personnel to support its current and future development plans or to otherwise successfully manage its growth; (h) the Company’s need for a dditional capital; and (i) whether imetelstat demonstrates disease-modifying activity. 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 periodic r eports filed with the Securities and Exchange Commission under the heading “Risk Factors,” including Geron’s quarterly report on Form 10 -Q for the quarter ended March 31, 2019. 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. 2

Agenda 8:00 am Welcome Suzanne Messere Investor Relations 8:05 am Introductions Aleksandra Rizo, M.D., Ph.D. Chief Medical Officer 8:10 am An Introduction to Myelofibrosis Rami Komrokji, M.D. Section Head – Leukemia and MDS, Moffitt Cancer Center, Tampa, Florida Imetelstat vs. RWD Comparative analyses of overall survival between Vice Chair, Malignant Hematology IMbark Phase 2 clinical data and real-world data Department, Moffitt Cancer Center, Presented at the 24th Annual Congress of the Tampa, Florida European Hematology Association Q&A 8:45 am An Introduction to Myelodysplastic Syndromes Uwe Platzbecker, M.D. Head of Medical Department I – Hematology and Cell Therapy, University Imetelstat in Lower Risk MDS of Leipzig Medical Center, Leipzig, Updated data from Phase 2 portion of the IMerge Germany clinical trial Presented at the 24th Annual Congress of the European Hematology Association Q&A 9:20 am Closing Remarks John A. Scarlett, M.D. Chairman and Chief Executive Officer

Introductions Aleksandra Rizo, M.D., Ph.D. Chief Medical Officer

Rami Komrokji, M.D. Current • Section Head – Leukemia and MDS, Moffitt Cancer Center, Tampa, Florida • Vice Chair, Malignant Hematology Department, Moffitt Cancer Center, Tampa, Florida • Senior Member and Professor of Oncologic Services, Moffitt Cancer Center, Tampa, FL • Previous Clinical Director, Malignant Hematology Department Lead Clinical Investigator, Moffitt Cancer Center, Tampa, Florida • Director Leukemia & Lymphoma Program, University of Cincinnati, Cincinnati, Ohio • Medical Training Jordan University School of Medicine, Amman, Jordan • Internal Medicine Resident, Case Western University, St. Vincent Program, Cleveland, Ohio • Hematology-Oncology Fellow, Strong Memorial Hospital, University of Rochester, Rochester, New York • Expertise Clinical trials in hematologic malignancies with a focus on myelodysplastic syndromes, myeloproliferative neoplasms and acute myeloid leukemia 5

An Introduction to Myelofibrosis Rami Komrokji, M.D. Moffitt Cancer Center

Myelofibrosis (MF) Disease characteristics • Malignant clonal proliferation and atypical megakaryocytic hyperplasia leads to bone marrow fibrosis and impaired hematopoiesis – Constitutional symptoms (e.g., fever, weight loss, night sweats, pruritus) present in approximately 35% of patients also thought to be due to cytokines produced by malignant megakaryocytes telomerase – Impaired bone marrow hematopoiesis shifts blood production to spleen and liver (palpable splenomegaly in approximately 80% of patients) – Fibrosis thought to be induced by inflammatory cytokines produced by megakaryocytes originating from the malignant progenitor cell clone • Serious and life-threatening illness − Leukemic transformation to AML (blast-phase MF) Higher telomerase activity and shorter telomere − Thrombohemorrhagic complications associated with dysfunctional length in patients with hematopoiesis myeloproliferative neoplasms − Median survival: ~1-3 years for Intermediate-2 or High-risk disease Inhibition of neoplastic Tefferi, JCO 2005; 23:8520-8530 progenitor cell growth Tefferi, Mayo Clin Proc 2012; 87:25-33 observed with telomerase Gangat et al, JCO 2011; 29:392-397 inhibition Ferraris, Blood; 2005a; 105(5):2138 – 2140 Harley, Nat Rev. 2008;8:167 – 179 7

Int-2/High-Risk MF Patient Population in the U.S. No approved drug for patients relapsed/refractory to ruxolitinib > 9,000 Imetelstat patient population* Int-2/High-risk MF patients in the U.S . ~75% > 2,000 of Int-2/High-risk MF patients Int-2/High-risk MF cases diagnosed annually in the U.S. * Intermediate-2/High-risk MF patients relapsed/refractory to JAK inhibitors Mehta et al, Leuk Lymphoma 2014; 55:595-600 Gangat et al, JCO 2011; 29:392-397 Geron Proprietary Market Research 8

Unmet Medical Need in Int-2/High-Risk MF Potential for meaningful survival in poor-prognosis patients Ruxolitinib • Primarily for symptoms or 75% splenomegaly Investigational Agent: • Oral JAK1/JAK2 inhibitor imetelstat 5-year ruxolitinib • Only approved product for discontinuation rate MF in U.S./Europe IMbark Phase 2 Trial: • Stay on drug as long as Primary reasons: Median Overall Survival of tolerated • Suboptimal response 28.1 months* for 9.4 mg/kg • Loss of therapeutic effect dosing arm After discontinuation of ruxolitinib Median Overall Survival is ~14-16 months Harrison et al, ASH 2015; Gupta et al, ASCO 2016 Newberry et al, Blood 2017; 130:1125-1131 Kuykendall et al, Ann Hematol 2018; 97:435-441 Spiegel et al, Blood Advances 2017; 1:1729-1738 *Geron press release: May 16, 2019; clinical cut-off of April 30, 2019 9

Analyses of IMbark Phase 2 Data vs RWD Presented at the 24th EHA Annual Congress Rami Komrokji, M.D. Moffitt Cancer Center

Favorable Overall Survival of Imetelstat-Treated Relapsed/Refractory Myelofibrosis Patients Compared with Closely Matched Real-World Data Andrew Kuykendall 1 , Ying Wan 2 , John Mascarenhas 3 , Jean-Jacques Kiladjian 4 , Alessandro Vannucchi 5 , Julia Wang 6 , Qi Xia 6 , Eugene Shu 6 , Faye Feller 2 , Aleksandra Rizo 2 , Jacqueline Bussolari 6 , Rami Komrokji, MD 1 1 Moffitt Cancer Institute, Tampa, FL, United States 2 Geron Corporation, Menlo Park, CA, United States, 3 Icahn School of Medicine at Mount Sinai, New York, NY, United States, 4 Hôpital Saint-Louis, Université Paris, Paris, France 5 AOU Careggi, University of Florence, Florence, Italy, 6 Janssen Research & Development, LLC, Raritan, NJ, United States Abstract# PS1456 Kuykendall et al . EHA 2019 Poster Presentation