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A New Era of Medicine October 27, 2026 NASDAQ: BEAM
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Today’s agenda 2 GSDIa: BEAM-301 Clinical Data at ESGCT Beam’s Vision for Leading a New Era of Medicine Introduction Amy Simon, M.D. Chief Medical Officer John Evans Chief Executive Officer Holly Manning Vice President, Investor Relations & External Communications Q&A Mr. Evans, Dr. Simon & Dr. Ciaramella TOPIC PARTICIPANT PKU: Beam’s Platform Approach in Action Giuseppe Ciaramella, Ph.D. President
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Cautionary note regarding forward-looking statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements include statements regarding: the therapeutic applications and potential of our technology, including with respect to GSDIa and PKU; our plans, and anticipated timing, to advance our programs, including risto-cel, BEAM-103, BEAM-301, BEAM-304 and BEAM-302; our plans and anticipated timing to present data from ongoing clinical trials; our anticipated regulatory interactions and filings; our current expectations and anticipated results of operations, including our expected use of capital; the sufficiency of our capital resources to fund operating expenses and capital expenditure requirements and the period in which such resources are expected to be available; and the therapeutic applications and potential of our technology, including our potential to develop lifelong, curative, precision genetic medicines for patients through base editing, including potential safety advantages, all of which are subject to known and unknown important risks, uncertainties and other factors that may cause our actual results, performance or achievements, market trends, or industry results to differ materially from those expressed or implied by such forward-looking statements. Therefore, any statements contained herein that are not statements of historical fact may be forward-looking statements and should be evaluated as such. Without limiting the foregoing, the words "anticipate," "expect," "suggest," "plan," "vision," “strategy,” “possibility,” “promise,” "believe," "intend," "project," "forecast," "estimates," "targets," "projections," "potential," "should," "could," "would," "may," "might," "will," and the negative thereof and similar words and expressions are intended to identify forward-looking statements. Each forward-looking statement is subject to important risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statement, including, without limitation, risks and uncertainties related to: our ability to develop, obtain regulatory approval for, and commercialize our product candidates, which may take longer or cost more than planned; our ability to raise additional funding, which may not be available; our ability to obtain, maintain and enforce patent and other intellectual property protection for our product candidates; that preclinical testing of our product candidates and preliminary or interim data from preclinical studies and clinical trials may not be predictive of the results or success of ongoing or later clinical trials; that initiation and enrollment of our clinical trials may take longer than expected; that our product candidates or the delivery modalities we rely on to administer them may cause serious adverse events; the uncertainty that our product candidates will receive regulatory approval necessary to initiate or continue human clinical trials, that our product candidates may experience manufacturing or supply interruptions or failures; risks related to competitive products; and the other risks and uncertainties identified under the headings "Risk Factors Summary" and "Risk Factors" and elsewhere in our annual report on Form 10-K for the year ended December 31, 2025, our quarterly reports on Form 10-Q, and in any subsequent filings with the Securities and Exchange Commission (the "SEC") which are available on the SEC's website at www.sec.gov. Additional information will be made available by our annual and quarterly reports and other filings that we make from time to time with the SEC. These forward-looking statements speak only as of the date of this presentation. Factors or events that could cause our actual results to differ may emerge from time to time, and it is not possible for us to predict all of them. We undertake no obligation to update any forward-looking statement, whether as a result of new information, future developments or otherwise, except as may be required by applicable law. 3 .
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4 Leading a new era of medicine Address the root cause of serious genetic diseases With one-time therapies that prevent a lifetime of disease progression Ending chronic treatment for patients Lowering lifetime costs for the healthcare system At Beam, we aim to:
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LESS GENOTOXICITY than traditional gene editing DURABLE correction for one-time cures CONSISTENT gene sequence outcomes Predictable, Transformative Outcomes for Patients Beam aims to correct the genetic root cause of severe diseases with base editing 5 BASE EDITING T E C H N O L O G Y D E S I G N E D F O R :
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Our vision for base editing is becoming a reality for patients 6 https://answers.childrenshospital.org/sickle-cell-base-editing/ https://www.nytimes.com/2025/03/10/health/gene-editing-beam-mutation-dna.html https://www.chop.edu/centers-programs/genetherapy4inheritedmetabolicdisorders/future-personalized-medicine-here-kjs 2024 2025 2025 2026 Alpha-1 antitrypsin deficiency (AATD)Sickle cell disease (SCD) Urea cycle disorder Glycogen storage disease Ia (GSDIa)
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Genetic correction could transform daily life for patients with GSDIa 77 Life today with GSDIa Vision after correcting root cause Constant vigilance, little room for error A life no longer organized around GSDIa No more cornstarch doses Constant spikes and plunges in glucose Normal, stable glucose levels Wake multiple times each night for scheduled cornstarch doses Sleep through the night 7 Freedom from around-the-clock dietary dosing Uninterrupted rest for patients and families Cornstarch doses every day, for life + emergency rescue kit Missing a dose can lead to severe hypoglycemia, coma or death
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100% (4/4) of programs achieved Phase 1/2 goals and clinical proof of concept Industry average: 15-30% The power of predictability: Beam is building a reliable model for advancing genetic medicine 8 Multiple growing, high-value franchises Active pipeline expansion Creative platform partnerships REUSABLE delivery technology CONSISTENT preclinical and clinical outcomes HIGHLY SCALABLE internal manufacturing FLEXIBLE emerging regulatory framework Easily ADAPTABLE to new targets 4/4 includes risto-cel, BEAM-302, BEAM-301 and BEAM-201. Industry average is per program from start of Phase 1 to end of Phase 2. Source: BIO report; Clinical Development Success Rates and Contributing Factors 2011–2020
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Building the capabilities and infrastructure to advance genetic medicines at scale 9 Decision in 2020 to establish in-house “full stack” production of CRISPR medicines Beam North Carolina: 100,000+ sq. ft. for manufacturing and quality release Beam Cambridge: Editing platform, automation and computational biology 200 FTEs for design and GMP production of customized gene correction doses Vertically integrated On-demand multi-scale production AI-enabled editor optimization >100 patients treated in clinical studies to date 8 IND/CTA approvals 3 FDA priority designations 100s of validated assays and procedures for cross- referencing to new programs
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Our most advanced, pivotal-stage programs target large markets and provide opportunity for significant value creation 10 Sickle Cell Disease (SCD) Alpha-1 Antitrypsin Deficiency (AATD) U.S. addressable population estimates per Beam internal data and market research. RISTO -CEL ~10K-100K U.S. patients eligible for ex vivo treatment and in vivo treatment, respectively • Differentiated clinical profile for risto-cel • Internal manufacturing • Poised to enter an established market with high patient demand • Next-wave in vivo approach making rapid progress BEAM -302 Beam has a long-term commitment to provide best-in-class therapies for SCD and AATD ~100K U.S. patients with severe (PiZZ) AATD • Potential first-in-class, one-time in vivo therapy addressing liver and lung manifestations • Only genetic medicine in pivotal trial for AATD • Designed to convert patients' disease risk to carrier-like status • Long-term leadership and commitment to AATD patients
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FDA Platform Regulations Applicable to Base Editing Base Editing and LNP Platform Technology FDA is embracing new regulatory paradigms for advanced therapies, potentially enhancing our ability to help more patients 11 “Toward a new framework for… individualized therapies” Peter Marks, Celia Witten Nature FDA Guidance: 1. “Use of the Plausible Mechanism Framework to Develop Individualized Therapies”* 2. “CMC Flexibilities for Gene Therapy Products” 3. “Leveraging Prior Knowledge in Gene Editing Products”* FDA Guidance: “Platform Technology Designation Program”* “FDA’s New Plausible Mechanism Pathway” Marty Makary, Vinay Prasad NEJM Pediatric Rare Disease Priority Review Voucher program renewed 2016-2017 2018-2023 2024 2026 2025 2025 Invention of base editing for precise CRISPR gene editing Beam industrializes base editing and builds internal manufacturing *Draft guidance as of October 2026
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We believe we have the potential to significantly expand the addressable patient population for gene correction 12 12 Sickle cell disease 100,000 patients in U.S. Alpha-1 antitrypsin deficiency 100,000 patients in U.S. Cabré-Romans J-J and Cuella-Martin R (2025) CRISPR-dependent base editing as a therapeutic strategy for rare monogenic disorders. Front. Genome Ed. 7:1553590. 7,000 rare diseases Affecting millions of patients 80% caused by a single genetic defect <5% have a treatment option
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GSDIa and PKU serve as examples of efficient, platform-based development of precision genetic medicines GSDIa: Efficient Development for Rare Indication • Initial clinical data suggest BEAM-301 restored endogenous glucose production following a single in vivo treatment • Two patients at 40 mg reached 15-hour fasting maximum and 100% decrease in daily starch intake • Data further validate Beam’s in vivo LNP capabilities and reusable delivery technology • 100% (4/4) of Beam programs have delivered clinical proof of concept in line with preclinical studies 13 PKU: Platform Approach to Reach Multiple Variants • Pursuing a multi-mutation approach using novel regulatory pathways • Beam selected third base editor for new PKU variant • BEAM-304 program now has potential to address up to 50% of U.S. patients with PKU
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GSDIa: Clinical Proof of Concept for BEAM-301 14 Amy Simon, M.D. Chief Medical Officer
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Glycogen storage disease Ia (GSDIa) patients are at risk of severe hypoglycemia and excessive accumulation of other metabolites 15 Mutation of G6Pase prevents glycogen conversion to glucose, resulting in severe drop in blood glucose levels within 1–4 hrs with fast Hypoglycemia may result in seizures or metabolic crisis that can be lethal Liver is often enlarged due to accumulated glycogen and lipid and adenomas are common BEAM-301 targets one of the most prevalent and severe mutations, R83C, estimated to affect 300 patients in U.S. GSDIa can be caused by a single point mutation Wildtype G6PC gene G6PC R83C mutation Non-functional G6Pase Glycogen Glucose Glucose-6- phosphate Pyruvate Acetyl-CoA Fatty acids, triglycerides
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BEAM-301 is designed to correct the R83C mutation causing GSDIa, utilizing non-viral, lipid nanoparticle (LNP) delivery to target the liver 16 Formulate LNP Lipid Base editor mRNA gRNA IV infusion Nuclear import T ▲ A Target DNA binding Expression of corrected G6PC gene Functional G6Pase Release of mRNA & gRNA Translation of editor protein A GCorrection editing LNP uptake
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In preclinical studies, treatment with a single dose of BEAM-301 significantly improved long-term survival in GSDIa mouse model 17 • Preclinical studies of BEAM-301 demonstrated a single dose significantly improved long-term survival out to a year in humanized R83C homozygous mice • Untreated homozygous R83C mice die within weeks of birth 0 Probability of Survival20 40 60 80 100 10 20 30 40 50 1x dose BEAM-301 wildtype Untreated Time (weeks) 0
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BEAM-301 Phase 1/2 study design 18 *List is not exhaustive; †3.3 mmol/L; ‡only follow-up visits during which patients are hospitalized for CFC are shown; §other criteria include lactate >10 mmol/L, pH <7.25, HCO3 <15 mmol/L, altered mental status, vomiting, loss of consciousness, OR patient requests to stop; ║total amount and number of doses per day BL, baseline; CGM, continuous glucose monitoring; D, Day; DLT, dose-limiting toxicity; GSDIa, glycogen storage disease type Ia; IV, intravenous; M, Month; TEAE, treatment-emergent adverse event; TTH, time to fasting hypoglycemia Screening Run-in Follow up‡ Enrollment Week −4 D1 M24 Controlled fasting challenge (CFC) to establish time to fasting hypoglycemia (TTH): • Stopping criteria include glucose <60 mg/dL†§ • Maximum allowable duration is 15 hours D36 M12M6 Cohort 3 60 mg N=3–6 (Enrolling) Dose exploration (dosing ongoing) Patient population Exploratory: Change from BL in % of time spent in euglycemia, hypoglycemia, and hyperglycemia (CGM); change from BL in glucose and metabolic parameters during CFCs Key endpoints* Cohort 1 20 mg N=3 (Completed) Cohort 2 40 mg N=3 (Completed) Primary: TEAEs, serious TEAEs, and DLTs Secondary: Change from BL in TTH; metabolic parameters over time; change from BL in starch supplementation║ 4 weeks BEAM-301 single IV infusion Key inclusion criteria* • Age ≥18 years • GSDIa diagnosis (one or two R83C copies) • ≥1 hypoglycemia episode <60 mg/dL† ≤2 years prior CFC CFC CFC CFC CFC
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Baseline demographics and clinical characteristics 19 Cohort 1: 20 mg (N=3) Cohort 2: 40 mg (N=3) Total (N=6) Age (years), median (range) 26.0 (26.0–43.0) 42.0 (26.0–50.0) 34.0 (26.0–50.0) Sex, n (%) Male 2 (66.7) 1 (33.3) 3 (50.0) Female 1 (33.3) 2 (66.7) 3 (50.0) BMI (kg/m2), median (range) 28.1 (24.3–43.8) 24.6 (22.5–53.4) 26.4 (22.5–53.4) Genotype, n (%) R83C homozygous 2 (66.7) 2 (66.7) 4 (66.7) R83C compound heterozygous* 1 (33.3) 1 (33.3) 2 (33.3) TTH (hours), median (range) 2.9 (1.1–3.0) 2.5 (2.3–3.1) 2.7 (1.1–3.1) Daily starch intake, median (range) Total dose (g/day) 315 (248.0–330.0) 255 (236.0–275.0) 265 (236.0–330.0) Number of doses 6 (6–7) 5 (5–6) 6 (5–7) Triglyceride (mg/dL), median (range) 260 (130.7–289.7) 237 (202.7–296.0) 248.5 (130.7–296.0) *All patients had the p.R83C and p.G270V mutations BMI, body mass index; TTH, time to fasting hypoglycemia • As of data cutoff (August 17, 2026), six patients have received BEAM-301 with a median (range) follow-up of 7.6 (1.9–16.6) months
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Safety profile of BEAM-301 consistent with LNP therapies 20 *No Grade 4 or 5 TEAEs were reported; †all serious TEAEs have resolved; ‡occurred in a patient who also had an IRR, with bilateral calf involvement, peak creatine kinase <1,000 U/L, and no renal involvement. ALT, alanine aminotransferase; AST, aspartate aminotransferase; DLT, dose-limiting toxicity; IRR, infusion-related reaction; IV, intravenous; TEAE, treatment-emergent adverse event Number of patients with events (%) Cohort 1: 20 mg (N=3) Cohort 2: 40 mg (N=3) Total (N=6) Any TEAE 3 (100) 3 (100) 6 (100) Related to BEAM-301 3 (100) 3 (100) 6 (100) Any TEAE ≥Grade 3* 2 (66.7) 1 (33.3) 3 (50.0) Related to BEAM-301 2 (66.7) 1 (33.3) 3 (50.0) Any serious TEAE† 2 (66.7) 2 (66.7) 4 (66.7) IRR 2 (66.7) 1 (33.3) 3 (50.0) Diarrhea 0 1 (33.3) 1 (33.3) Rhabdomyolysis‡ 0 1 (33.3) 1 (33.3) Serious TEAE related to BEAM-301 2 (66.7) 2 (66.7) 4 (66.7) Any DLT 0 0 0 Any TEAE leading to death 0 0 0 Any TEAE leading to dose withdrawal 0 0 0 IRR Grade 1 / 2 / 3 1 (33.3) / 1 (33.3) / 2 (66.7) 0 / 1 (33.3) / 1 (33.3) 1 (16.7) / 2 (33.3) / 3 (50.0) ALT elevation Grade 1 / 2 / 3 2 (66.7) / 0 / 0 2 (66.7) / 0 / 0 4 (66.7) / 0 / 0 AST elevation Grade 1 / 2 / 3 2 (66.7) / 0 / 0 1 (33.3) / 1 (33.3) / 0 3 (50.0) / 1 (16.7) / 0 • BEAM-301 20 mg and 40 mg showed an acceptable safety profile, with no dose- limiting toxicities, no TEAE-related discontinuations, and no Grade 4/5 TEAEs • IRRs and transient transaminase elevations were the most frequent treatment-related TEAEs, consistent with the known safety profile of IV LNPs – IRRs occurred in 5/6 patients, comprising three serious Grade 3 events and three that were nonserious (two Grade 2, one Grade 1); all events resolved with or without treatment – Use of shorter-acting, lower-potency corticosteroids may have contributed to IRR severity; premedication and infusion rate regimens have been modified – Transaminase elevations were primarily Grade 1, transient, and resolved without intervention; patients remained asymptomatic and total bilirubin remained within normal limits
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In the 40 mg cohort, 2 out of 3 patients demonstrated restoration of glucose production during the controlled fasting challenge (CFC) 21BMI, body mass index (kg/m2); CFC, controlled fasting challenge; CH, compound heterozygous; D, day; HZ, homozygous; M, month; TTH, time to hypoglycemia Cohort 1: 20 mg Cohort 2: 40 mg Time to fasting hypoglycemia (hours) Patient 1: HZ; BMI 43.8 Patient 2: CH; BMI 28.1 Patient 3: HZ; BMI 24.3 Patient 4: HZ; BMI 22.5 Patient 5: HZ; BMI 24.6 Patient 6: CH; BMI 53.4 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 BL D36 M6 M12 BL D36 M6 M12 BL D36 M6 BL D36 BL D36 BL D36 Allowable fasting duration • Median (range) time to hypoglycemia (TTH) increased from 2.9 (1.1–3.0) hours at baseline to 4.3 (1.3–4.6) hours at Day 36 in the 20 mg cohort, and from 2.5 (2.3–3.1) hours to 15.0 (2.8–15.0) hours in the 40 mg cohort • In the 40 mg cohort, two of three patients achieved the protocol-defined maximum CFC duration (TTH) of 15 hours, consistent with endogenous glucose production
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Daily starch requirements post-BEAM-301 generally decreased and were eliminated in two patients 22 0 1 2 3 4 5 6 7 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 BL 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Change in total daily starch intake (%) 0 1 2 3 4 5 6 7 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 BL 1 2 3 4 5 6 7 8 9 10 11 12 13 0 1 2 3 4 5 6 7 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 BL 1 2 3 4 5 6 7 8 9 10 Number of daily starch dosesPatient 1 Patient 2 Patient 3 0 1 2 3 4 5 6 7 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 BL 1 2 3 4 5 6 Change in total daily starch intake (%) 0 1 2 3 4 5 6 7 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 BL 1 2 3 4 Patient 4 Patient 5 Patient 6 Number of daily starch doses 0 1 2 3 4 5 6 7 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 BL 1 2 Time (months) Time (months) Time (months) BL, baseline • Two of three patients in the 40 mg cohort no longer required any starch supplementation and maintained glucose within the normal range Time (months) Time (months) Time (months) Change in total daily starch intake (%) Number of daily starch doses Cohort 1: 20 mg Cohort 2: 40 mg
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Conclusions Initial data from the BEAM-301 study demonstrate an acceptable safety profile and suggest induction of G6Pase activity in patients with GSDIa: • Safety profile across 20 mg and 40 mg doses that is consistent with known risks associated with IV LNP administration • Evidence of significant endogenous glucose production in GSDIa after single-dose administration • Two of three patients in the 40 mg cohort reached the 15-hour fasting maximum, accompanied by a 100% reduction in daily starch intake (i.e., freedom from any starch supplementation) • No overall increase in time spent in hypoglycemia despite significantly reduced starch intake Based on these results, patients are now being recruited into the 60 mg dose cohort 23GSDIa, glycogen storage disease type Ia; IV, intravenous; LNP, lipid nanoparticle
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BEAM-301 Phase 1/2 trial in GSDIa patients with R83C mutation continues to enroll and supports FDA dialogue for pivotal expansion 24 KEY ENDPOINTS • Safety and tolerability • Time to hypoglycemia during fasting • Changes from baseline in starch supplementation • Enrollment in 60 mg cohort underway • Align with FDA on pathway to potential approval for BEAM-301 PHASE 1/2 Open-label, single- ascending dose trial 20 mg N = 3 COMPLETE 40 mg N = 3 COMPLETE 60 mg N = 3-6 ENROLLING Pivotal Expansion at Optimal Dose
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Beam’s growing metabolic disease expertise creates opportunities for unique synergies in treating rare metabolic liver diseases 25 Commercial • Strong connections in the metabolic disease community • Focused commercial effort can support multiple metabolic indications • Specialized metabolic disease treatment centers • Leverage market access infrastructure in gene therapy Clinic • Multi-center registries, patient advocacy groups and metabolic treatment centers for patient education and referrals • Efficiently test new products targeting different mutations under the same master clinical protocol and IND • Experience in dietary management strategies that are fit-for-purpose Translation • Shared biological pathways across some indications • Experience translating editing to enzymatic activity in humans based on animal model and in vitro data • Low threshold for clinical benefit • Readily available biomarkers
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PKU: Beam’s Platform Approach in Action Giuseppe Ciaramella, Ph.D. President 26
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PRECISION GENETIC MEDICINES PLATFORM The power of predictability: Beam is building a reliable model for advancing genetic medicine 27 Multiple growing, high-value franchises Active pipeline expansion Creative platform partnerships REUSABLE delivery technology CONSISTENT preclinical and clinical outcomes HIGHLY SCALABLE internal manufacturing FLEXIBLE emerging regulatory framework Easily ADAPTABLE to new targets
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PKU is an example of the platform in action 28 REUSABLE delivery technology CONSISTENT preclinical and clinical outcomes HIGHLY SCALABLE internal manufacturing FLEXIBLE emerging regulatory framework Easily ADAPTABLE to new targets Targeting multiple mutations with same underlying platform Builds on LNP capabilities validated by BEAM-302 and BEAM-301 clinical programs Consistent preclinical outcomes across three PKU variants Shared components between BEAM-302 and BEAM-304 manufacturing accelerate development One IND for all PKU variants and one master clinical protocol for development
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R408W Mutation B Mutation CMutation D Mutation E Mutation F Mutation G Mutation H Mutation I Mutation J Mutation K Additional Mutations BEAM-304 has potential to address vast majority of patients with PKU, leveraging an efficient development approach 29 ~20,000 Individuals with PKU in U.S. Source: Beam internal data; Hillert, Alicia et al. The American Journal of Human Genetics, Volume 107, Issue 2, 234 – 250; Stone WL, Los E. Phenylketonuria (PKU). StatPearls Publishing; 2025 Jan • Hundreds of mutations in phenylalanine hydroxylase (PAH) cause PKU • Beam has potential to develop a first- in-class, one-time in vivo treatment for the vast majority of patients with PKU • Multi-mutation approach has potential to utilize novel regulatory pathways • BEAM-304 program advancing three base editors for distinct mutations to the clinic with potential to address up to 50% of U.S. patients with PKU • Limited competition BEAM-304A BEAM-304B BEAM-304C
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PKU Platform Product A platform approach allows us to leverage nonclinical and clinical data across PKU product variants 30 Same physicochemical characteristics Same PK and biodistribution Same toxicity Expectation of same safety and clinical efficacy Evaluate safety with first PKU platform variant (BEAM-304A) only Plan to add each subsequent mutation to the same IND, clinical trial protocol, BLA BEAM -304A Base Editor mRNA Guide RNA BEAM -304B Base Editor mRNA Guide RNA BEAM -304C Base Editor mRNA Guide RNA PKU patient with mutation A PKU patient with mutation B PKU patient with mutation C Same LNP delivery Patient-specific payloads (A, B, C)
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Mutation A Mutation B Mutation C Vehicle 0.1 mg/kg 0.3 mg/kg 0 500 1000 1500 Phe Concentration (μM) 360 μM Potent correction of three different PAH mutations consistently normalized blood Phe in mouse models of PKU 31 Data shown are plasma Phe in respective mouse models 7 days after LNP administration • BEAM-304 platform approach yielded predictable and reproducible results in preclinical models • Preclinical results informed the selection of three base editors: BEAM-304A, BEAM-304B, and most recently, BEAM- 304C, targeting a mutation affecting ~4% of individuals with PKU Vehicle 0.3 mg/kg 0 500 1000 1500 Phe Concentration (μM) 360 μM Vehicle 0.1 mg/kg 0.3 mg/kg 0 500 1000 1500 Phe Concentration (μM) 360 μM
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BEAM-304 DOSE EXPLORATION Phase 1/2 study designed to evaluate the safety and efficacy of all BEAM-304 editors under one IND and one master protocol 32 Key Inclusion Criteria: 1. Adults or adolescents 12 through 65 years old 2. PAH gene with target PKU-causing variant Key endpoints Safety and tolerability Blood Phe reduction Diet liberalization 3. At least one historical Phe ≥600 μmol/L 4. Screening Phe ≥360 μmol/L Cohort A1 Cohort A2 Cohort A3 Cohort A4BEAM-304A Subsequent base editors added to trial will start at BEAM-304A optimal dose BEAM-304 PHASE 2 DOSE EXPANSION BEAM-304B BEAM-304C etc……
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Beam has the platform, programs and capital to become a leading genetic medicines company that ushers in a new era of medicine 33 A Platform That Learns and Repeats • Apply shared editing, delivery and manufacturing capabilities to new and existing clinical programs • Derisked editing and delivery across >100 patients and 4 clinical programs • Expand into new targets and delivery contexts Financial Capacity to Execute • $1.2B in cash as of June 30, 2026* • Sixth Street facility structured to fund potential risto-cel launch • Expected runway into mid-2029 under current assumptions** Multiple Near-term Value Drivers • Advance risto-cel toward BLA submission • Execute BEAM-302 pivotal trial • Generate proof of concept for additional in vivo programs BEAM IS BUILDING THE LEADING GENETIC MEDICINES COMPANY *Inclusive of cash, cash equivalents, and marketable securities. **Inclusive of potential additional $200 million expected to be drawn from Sixth Street facility.
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34 THANK YOU Kyle LIVING WITH SICKLE CELL DISEASE Dan LIVING WITH ALPHA-1 ANTITRYPSIN DEFICIENCY Alyssa and Gayle LIVING WITH GLYCOGEN STORAGE DISEASE TYPE IA