Pioneering mRNA Cell Therapy for Autoimmunity May 2026
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Executive summary 3 Cartesian’s lead asset, Descartes-08, delivers deep and durable responses in MG through 12 months following a single course of therapy—administered outpatient without lymphodepletion—positioning it to transform the current treatment landscape. The Phase 3 AURORA trial positions Descartes-08 to capture a $1B+ market opportunity in MG*, with Phase 3 data expected in 1Q27 and BLA filing in mid-2027 US-based in-house manufacturing supports commercial readiness for MG launch with potential biologic-like margins and full supply chain control – ongoing process optimization creates opportunity for further margin expansion. Data from the Phase 1/2 HELIOS trial in pediatric autoimmune diseases, including JDM, expected in 4Q26 Phase 2 TRITON trial in myositis initiated, positioning Descartes-08 to address a multi-billion dollar market opportunity due to the significant unmet need, with data expected in 1H27 *Internal company projectionsPIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY MG, myasthenia gravis JDM, juvenile dermatomyositis Cash runway into 2028 • ~-==------==----=================================================-----==-----==~7 ·~================================7
4 Late-stage clinical company pioneering mRNA cell therapy specifically designed to expand the reach of cell therapy to autoimmunity • mRNA cell therapy designed to be dosed reliably and safely in an outpatient setting without lymphodepletion • Descartes-08: Investigational mRNA CAR T-cell (CAR-T) with deep and durable responses through 12 months observed in randomized, double-blind, placebo-controlled Phase 2b trial in patients with myasthenia gravis (MG) • US-based in-house manufacturing supports commercial readiness with potential for biologic- like margins *As of March 31, 2026; includes cash, cash equivalents and restricted cash; excludes cash obtained or committed through non-dilutive financing deal with K2 HealthVentures SLE, Systemic Lupus Erythematosus CAR, Chimeric antigen receptor • Phase 3 AURORA trial data expected in 1Q27; positions Descartes-08 to potentially access $1B+1 market opportunity in MG • Phase 2 TRITON trial in myositis data expected in 1H27; positions Descartes-08 to address a multi-billion dollar market opportunity due to significant unmet medical need2 • Data from Phase 1/2 HELIOS pediatric trial in children and young adults with autoimmune diseases, including JDM, expected in 4Q26 DESCARTES-08 RECENT AND PLANNED ACTIVITY • Strong balance sheet with approximately $120 million* • Secured up to $150 million of non-dilutive financing from K2 HealthVentures; funding of $50 million from initial tranche received in May 2026 • Expected to support planned operations into 2028 CASH RESOURCES 1. Internal company projections 2. Kronzer et al., 2021; Coffey et al., 2021; Marotta et al., 2020; OCTAGAM efficacy data PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY5 Cartesian’s mRNA approach is designed to expand the reach of potent cell therapy products to address autoimmunity No Lymphodepletion No associated cytopenia, secondary malignancies, or other chemotherapy toxicities Administered Outpatient Convenient dosing schedule Delivered at Therapeutic Levels Administered at therapeutic doses without uncontrollable proliferation Transient Cell Modification Does not carry risk of genomic integration
Asset Indications Discovery/Preclinical Phase 1 Phase 2 Phase 3 Descartes-08 Autologous mRNA CAR-T Myasthenia Gravis Myositis (Dermatomyositis & Antisynthetase Syndrome) Juvenile Dermatomyositis Wholly-owned pipeline targets autoimmune disease 6 PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
Engineered by transfection of autologous CD8+ T cells with mRNA encoding anti-BCMA CAR Granted U.S. FDA orphan and RMAT designations for generalized myasthenia gravis, and RPDD for juvenile dermatomyositis Typical lot processed for infusion within as little as ~3 weeks RMAT, Regenerative Medicine Advanced Therapy RPDD, Rare Pediatric Disease Designation PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY7 Descartes-08 is an mRNA CAR T-cell therapy in clinical development for autoimmune disease FDA, U.S. Food and Drug Administration BCMA, B-cell maturation antigen Autoreactive Tn, cell Activated \l Bcell Neuromuscular junction Plasma cell
8 Descartes-08 in Myasthenia Gravis PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
9 Myasthenia gravis is a rare, progressive autoimmune disease with significant unmet need Characterized by debilitating fatigue and muscle weakness Limbs Respiratory Ocular Facial 106,000+ Patients in the U.S.1 Current treatments require chronic or frequent administration and have limited durability Significant Unmet Need Remains • Highly heterogenous disease biology makes a standardized treatment approach ineffective2 • Limited durability from current therapies requires patients to rely on chronic immunosuppression and dosing3 • Suboptimal depth and durability of response leaves white space for long-lasting remission3 • Achievement of minimal symptom expression over time remains a key treatment goal for physicians4 1. Rodrigues et al. 2023 2. DOI: 10.1080/1744666X.2021.1936500 3. VYVGART label 4. Company neurologist ad-board PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY =) Cartesian. {= therapeutics
10 AURORA: Randomized double-blind, placebo-controlled Phase 3 trial of Descartes-08 in AChR Ab+ gMG with data expected in 1Q27 WK1 Masked Dosing Six weekly doses of Descartes-08 or placebo PRIMARY ENDPOINT • Proportion of participants with MG-ADL improvement of ≥3 points at Month 4, relative to placebo • Proportion of participants with MGC improvement of ≥4 points at Month 4 WK6 WK8 WK12 WK16 Masked Follow-Up Month 1, Month 2, Month 3, Month 4 Primary Endpoint Assessment Optional Descartes-08 infusions Follow-Up Month 5, Month 6, Month 9, Month 12 Follow-Up Month 5, Month 6, Month 9, Month 12Descartes-08 Placebo ~100 Participants 1:1 INCLUSION CRITERIA • AChR Ab+ • MGFA Class II-IV • MG-ADL ≥6 • On stable doses of immunosuppressants Single infusion MG-ADL, Myasthenia Gravis Activities of Daily Living scale gMG, Generalized myasthenia gravis MGFA, Myasthenia Gravis Foundation of America MGC, Myasthenia Gravis Composite MG QMG, Quantitative MG Scores MG QoL 15R, MG Quality of Life 15-revised AChR Ab+, Acetylcholine receptor autoantibody positive KEY SECONDARY ENDPOINTS • MG-ADL and MGC change from baseline to Month 4 • Quantify clinical effect of Descartes-08 over 1 year PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY I :x:. :. .................. , I C . . . . : ................... aurora TRIAL
Deepening responses observed in participants treated with Descartes-08 11 • Average MG-ADL reduction of 5.5 (±1.1) points at Month 4, maintained through Month 12 (4.8±1.4) • Average QMG reduction of 4.8 (±1.7) points at Month 4, deepened through Month 12 (6.0±2.1) • 83% of participants reaching Month 12 maintained clinically meaningful response Primary Efficacy Dataset Month 3 (n=15), Month 4 to Month 12 (n=12*) *Three participants lost to follow-up Descartes-08 Placebo Clinically meaningful decrease Clinically meaningful decrease PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY 33% of participants achieved minimum symptom expression at Month 6 and maintained it through Month 12 D1M1M2M3M4 M6 M9 M12 0 -1 Q) L.. 8 -2 .............................................................................................. . en .....I 0 <( -3 I (9 ~ -4 -5 -6 ■ ■ D1 M1 M2 M3 M4 -1 Q) -2 L.. 0 (.) M6 M9 M12 (/') -3 ..................................................................................................... .. (9 ~ 0 -4 -5 -6
Deep responses observed in participants with no prior exposure to complement or FcRn inhibitors 12 • Average MG-ADL reduction of 6.6 (±1.5) points at Month 4, maintained through Month 12 (7.1±1.9) • Average QMG reduction of 6.0 (±2.3) points at Month 4, deepened through Month 12 (9.4±2.3) • 100% of participants maintained clinically meaningful response at Month 12 Primary Efficacy Dataset (No Prior Biologics) Month 3 (n=9), Month 4 (n=7*), Month 6 (n=7), Month 9 (n=7), Month 12 (n=7) *Two participants lost to follow-up Descartes-08 Clinically meaningful decrease Clinically meaningful decrease 57% of participants achieved minimum symptom expression at Month 6 and maintained it through Month 12 PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY D1M1M2M3M4 M6 M9 M12 0 Q) -2 ..... ........ .. .... .. .... .. .... ... ..... ............... .. .... .. ..... ...... .. ... .. .... .. .... .. .... . ~ 0 (.) Cl) _J ~ -4 I (9 ~ -6 -8 ■ D1 M M2 M3 M4 M6 M9 M12 0 -2 ~ 0 -4 (.) Cl) (9 ~ -6 a -8 -10 =)_ Cartesian. {= therapeutics
13 Safety profile supports outpatient administration with no AEs reported after Month 3 through final follow-up Descartes-08 (n=20) Placebo (n=16) Grade 1 Grade 2 Grade 3 Grade 1 Grade 2 Grade 3 Headache 7 (35%) 4 (20%) 2 (13%) 3 (19%) Chills 8 (40%) 4 (20%) Nausea 3 (15%) 6 (30%) 1 (6%) 2 (13%) Fever 7 (35%) 4 (20%) 1 (5%) Fatigue 4 (20%) 1 (5%) 1 (6%) Myalgia 4 (20%) 2 (10%) Infusion related reaction 1 (5%) 2 (10%) 1 (5%) 1 (6%) Muscle weakness 1 (5%) 1 (5%) 1 (6%) Arthralgia 1 (5%) 1 (5%) 1 (6%) Tachycardia 3 (15%) Upper respiratory infection 1 (5%) 1 (6%) Herpes simplex reactivation 1 (5%) 1 (5%) Dysgeusia 3 (15%) Diarrhea 1 (5%) 1 (6%) Sweating 1 (5%) 1 (6%) Limb edema 1 (5%) 1 (5%) Flushing 2 (10%) Dyspnea 1 (5%) 1 (5%) Insomnia 2 (10%) Vomiting 2 (10%) 1 (5%) Tremor 2 (10%) • Most commonly observed AEs through Month 3 include: headache, chills, nausea and fever, all of which typically resolved within 24 hours of infusion • No AEs reported after Month 3 • No hypogammaglobulinemia or increased infections reported • No difference in vaccine titers between Descartes-08 and placebo Total AEs reported through Month 12 for Descartes-08-treated patients and through Month 3 for placebo-treated patients Safety dataset comprises all subjects who received at least one dose of Descartes-08 (n=20) or placebo (n=16) All Grade 1–2 adverse events deemed possibly, probably or definitely related to the study drug with a cumulative incidence ≥10% and all Grade 3 adverse events deemed possibly, probably or definitely related to the study drug are reported. There were no Grade 4 adverse events PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
Phase 2a trial update: Descartes-08 retreatment continues to elicit deep and durable responses Nature Medicine publication can be found here • Three participants retreated to date, two of whom maintain minimum symptom expression 2 years after initial treatment • Third participant’s response deepened from a 4-point MG-ADL reduction at Month 2 to a 9-point improvement in MG-ADL at Month 12 following retreatment 14 Participant 1 Participant 2 PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY Descartes-08 infusions 25 Q) 20 .... 0 ~ 15 (_) ('.) 10 ::?! 5 0 M4 Descartes-08 infusions 20 Q) o 15 (.) en u 10 ('.) ::?! 5 0 M4 M6 M9 M6 M9 Descartes-08 retreatment M12 l ll lll M12 M15 M15 M18 M21 Descartes-08 retreatment M18 M21 JI I I I I M24 M24
15 Current gMG market lacks disease modifying treatments creating the potential to access a $1B+ market opportunity for Descartes-08 in the US Estimated US Patient Population: 106,0001 AChR+: ~85%2 RNAC US Potential Addressable Market: ~$1B+3 Significant reduction in MG-ADL of 7.1 at Month 124 with a single course of therapy 57% of patients achieved minimal symptom expression at Month 6 and maintained it through Month 124 Safety profile supports biologic-like outpatient administration Significant unmet need remains given current treatment options, creating a potential $1B opportunity 1. Rodrigues et al. 2023 2. Lazaridis et al., 2020 3. Company internal projections, inclusive of opportunity to retreat patients 4. Metrics reflective of results from biologic naïve population DESCARTES-08 OBSERVATIONS PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
Descartes-08 is optimally designed for autoimmune diseases Key Characteristics for a Differentiated Therapy Designed for Patient Adoption in MG Durability of Response Descartes-08 delivers deep and durable responses through 12 months after a single course of therapy Single Course of Therapy Unlike current biologic therapies requiring chronic dosing and immunosuppression, Descartes-08 delivers deep and durable responses after a single course of therapy through a precision immune reset Outpatient Administration mRNA cell therapy enables reliable and safe outpatient dosing without lymphodepletion, avoiding the risks of CRS and ICANS Redosing Optionality The favorable safety profile of mRNA cell therapy enables repeat dosing if needed, providing flexibility PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY CRS, Cytokine release syndrome ICANS, Immune effector cell-associated neurotoxicity syndrome
17 Descartes-08 Expansion into Myositis PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
18 Expansion into myositis provides new opportunity in an area with significant unmet need and compelling market Characterized by debilitating muscle weakness and skin rashes2 Limbs Respiratory Rashes Swallowing 80,000+ Patients in the U.S.1 60% of Patients Eligible for a 3L+ Treatment3 Residual Unmet Needs in Myositis4-5 Refractory, moderate-to-severe myositis patients likely to remain underserved despite new drug developments Treatment options have limited efficacy in broader organ involvement and refractory patients Better tolerated therapies desired given concern over infusion-related reactions Highly heterogenous disease leads to suboptimal speed and accuracy of diagnosis 1. Kronzer et al., 2021; Coffey et al., 2021; Marotta et al., 2020 2. HSS - Myositis 3. OCTAGAM efficacy data 4. Gupta et al. 2023; 5. Meyer et al. 2019; PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY =) Cartesian. {= therapeutics
19 Strong mechanistic alignment with existing clinical data in MG and SLE underscores a potential multi-billion-dollar opportunity in myositis for Descartes-08 Estimated US Patient Population: 80,0001 3L+ Treatment ~60%2 RNAC US Potential Addressable Market: Multi-billion- dollar3 Descartes-08 opportunity represented by 60% of patients remaining underserved Treated Population 40%Refractory Patients 60% 1. Kronzer et al., 2021; Coffey et al., 2021; Marotta et al., 2020 2. OCTAGAM efficacy data 3. Internal company projections, inclusive of opportunity to retreat patientsPIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
20 Myositis seamless clinical trial design provides potential opportunity for single pivotal trial with data expected in 1H27 Screening Days -60 to -18 Leukapheresis & Cell Processing Days -59 to -17 ~3 Weeks Vein-to-Vein Time Descartes-08 Day 1, 8, 15, 22, 29, 36 Follow-Up Visits Weeks 8, 12, 16 Primary Endpoint Assessment Week 24 Placebo Day 1, 8, 15, 22, 29, 36 ~3 Weeks Vein-to-Vein Time 1:1 randomization Days -7 to -3 Evaluate the first 10 patients to determine the path to a pivotal trial INCLUSION CRITERIA • Adults with moderate to severe multi-refractory dermatomyositis and antisynthetase syndrome PRIMARY OBJECTIVE • Assess safety and efficacy of Descartes-08 compared to placebo added to standard of care in patients with myositis at Week 24 SAMPLE SIZE • 10 participants prior to interim analysis • Up to 50 participants total treated (25 each arm) ■■■■ triton TRIAL • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • ■■■■ ■■■■
PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY21 Phase 1/2 trial of Descartes-08 in children and young adults with autoimmune diseases initiated with data expected in 4Q26 • Rare Pediatric Disease Designation for DC-08 in juvenile dermatomyositis granted in September 2024 • Trial initiation announced on January 9, 2026 • Data expected in 4Q26 DL, Dose level DLT, Dose limiting toxicity Dose escalation (n=3) Week 1: DL 1 Week 2: DL 2 Week 3: DL 3 Weeks 4–6: DL 3 (if no DLTs) Juvenile Dermatomyositis Expansion (n=10) Weeks 1–6: MTD once-weekly • No lymphodepleting chemotherapy • No integrating vectors • Fully outpatient treatment with 1hr post-infusion monitoring • No observed CRS or ICANS DC-08’s observed safety profile combined with significant unmet need in pediatric autoimmune disease supports clinical development plan Anticipated Pediatric Basket Trial Timeline MTD, Maximum tolerated dose ICANS, Immune effector cell-associated neurotoxicity syndrome CRS, Cytokine release syndrome helios TRIAL
22 Manufacturing PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
23 Wholly-owned, in-house, US-based manufacturing FUTURE GROWTH Clinical and commercial manufacturing scale capabilities support maturing pipeline and future growth QUICK TO ADAPT Continuous process optimization creates opportunity for progressive margin expansion WHOLLY-OWNED Ownership of quality control and production timelines COST EFFICIENT Supports commercial readiness for MG launch with potential for biologic-like margins Facility located in Frederick, MD Over 35,000 sq. ft. state- of-the-art cGMP facility PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY cGMP, current good manufacturing practice • • • . . • =) Cartesian. {= therapeutics
24 FINANCIAL POSITION: Current Cash and Cash Equivalents Expected to Support Pipeline Through Key Milestones All metrics as of 3/31/26; excludes cash obtained or obtained through non-dilutive financing deal with K2 HealthVentures *Includes Series A Non-Voting Convertible Preferred Stock and Series B Non-Voting Convertible Preferred Stock that remain subject to beneficial ownership limitations that are convertible into shares of common stock and includes outstanding options, RSUs and warrants. $120.4M ~75 FULL TIME EMPLOYEES Based in Gaithersburg, MD and Frederick, MD 28.5M Basic shares outstanding 38.0M Fully diluted shares outstanding* In cash, cash equivalents and restricted cash PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY25 Our team | Management Carsten Brunn, PhD PRESIDENT AND CEO Blaine Davis CHIEF FINANCIAL OFFICER Emily English, PhD CHIEF OPERATIONS OFFICER Matthew Bartholomae GENERAL COUNSEL, SECRETARY Peter Traber HEAD OF R&D
Key takeaways 26 Cartesian’s lead asset, Descartes-08, delivers deep and durable responses in MG through 12 months following a single course of therapy—administered outpatient without lymphodepletion—positioning it to transform the current treatment landscape. The Phase 3 AURORA trial positions Descartes-08 to capture a $1B+ market opportunity in MG*, with Phase 3 data expected in 1Q27 and BLA filing in mid-2027 US-based in-house manufacturing supports commercial readiness for MG launch with potential biologic-like margins and full supply chain control – ongoing process optimization creates opportunity for further margin expansion. Data from the Phase 1/2 HELIOS trial in pediatric autoimmune diseases, including JDM, expected in 4Q26 Phase 2 TRITON trial in myositis initiated, positioning Descartes-08 to address a multi-billion dollar market opportunity due to the significant unmet need, with data expected in 1H27 *Internal company projectionsPIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY MG, myasthenia gravis JDM, juvenile dermatomyositis Cash runway into 2028 • ~-==------==----=================================================-----==-----==~7 ·~================================7
27 Appendix PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY
Descartes-08 is designed for dual action, precisely targeting two key BCMA+ cell populations involved in a spectrum of autoimmune diseases 28 Several autoimmune disease segments involve pathogenic contributions from both PCs/plasmablasts and pDCs, including rheumatology, nephrology, neurology, and others Selectively deleting PCs/plasmablasts and pDCs, if successful, may create a differentiated cell therapy platform • Descartes-08 is designed to target BCMA, a surface antigen expressed on plasma cells/plasmablasts and plasmacytoid dendritic cells PLASMA CELLS (PCs) AND PLASMABLASTS • PCs, plasmablasts and proliferating B cells targeted by Descartes-08 represent a tiny fraction of B cells • These cells are entirely responsible for secreting pathogenic autoantibodies • During autoimmunity, autoantibodies attack host tissue and drive inflammation PLASMACYTOID DENDRITIC CELLS (pDCs) • pDCs, which Descartes-08 is designed to target, are a rare subset of antigen-presenting cells • These cells secrete high levels of cytokines (i.e., type I interferons) that cause inflammation and tissue damage during many human autoimmune diseases • pDCs are increased in patients with autoimmunity and interfere with optimal treatment PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY Plasma cell Attack of disease-specific host tissues Ab-bound nuclear antigen pDC activation type I interferons Cytokine driven Inflammation and tissue damage
PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY29 Meaningful reductions in MG-ADL at Month 3 were sustained through Month 12 with Descartes-08 in AChR+ gMG There was a significant and clinically meaningful reduction in mean [SD] MG-ADL score at Month 3 for the Descartes-08 AChR+ group versus placebo (-3.4 [2.8] vs -0.6 [2.9], p=0.0409), which was sustained through Month 121 Visit 8 11 8 11 8 10 8 11 0 8 0 8 0 7 0 7 Placebo Descartes-08 Clinically meaningful decrease D1 D29 D57 D85 D113 M6 M9 M12 2.5 0.0 -2.5 -5.0 Treatment Placebo Descartes-08 M G -A D L sc or e ' ~ . .1' ✓• ~ -------- ~----·--- ~ . -------- ... - ----- ------- --------------~ -- - -; ~ /·------. ' ' • • ___. ........ -.... ·- -----........., ' ' • -•-. . . -•-.
PIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY30 Descartes-08 focuses the T-cell repertoire and selectively alters the autoreactome, showing clear biological activity Descartes-08 focuses the T-cell repertoire in a manner that correlates with clinical effect p=0.048 (Wilcoxon signed rank test) TCR Diversity D57 vs D1 Data show Clinical Score and TCR Sequencing TCR Diversity (Downsampled Rearrangements) in Phase 2a samples analyzed at Adaptive Biotechnologies (R06 dataset). For certain subjects where TCR sequencing sample data was unavailable, D1 data was imputed from Screen, and D57 data was imputed from D85. Samples from one re-treated patient were analyzed as indicated. P-value is provided for Wilcoxon matched-pairs signed rank test on all primary-treatment data pairs from D1 vs D57. Descartes-08 selectively alters the self-reactive branch of the antibody repertoire (i.e., autoreactome1) 1Bodansky et al., Journal of Clinical Investigation 2024, doi: 10.1101/2023.12.19.23300188. Serum analysis of 2Myasthenia gravis patients receiving Rituximab targeting CD20+ B cells, 3lymphoma patients receiving conventional CD19 DNA CAR-T, or 4gMG patients following infusion with DC-08. Data compare D85 to D1 for MG open label cohort (N=13). Pe ar so n R- Va lu e 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 051015 0 20000 40000 60000 80000 100000 Clinical Score (MG-ADL) TC R di ve rs ity (C lo no ty pe s/ 10 0K ) D1 D57 Timepoint Retreatment Minimal change in autoreactivity Pe ar so n R- Va lu e 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 R = 0.887 3CD-19 CAR-T (Lymp) Pe ar so n R- Va lu e 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 R = 0.850 4DC-08 BCMA CAR-T (MG) R = 0.493 2Rituximab/CD-20 (MG)T cell Repertoire vs. clinical score (MG-ADL) Large change in autoreactivity TCR, T-cell receptor • • 0 I
31 Baseline characteristics: Patients in open-label Phase 2 SLE trial Participant Sex Age SLE Duration (years) Baseline SLEDAI- 2K Prior Rx Ongoing Rx Patient A F 44 19 8 MMF MMF, HCQ Patient B F 42 23 12 - Prednisone 2.5mg, HCQ, MMF Patient C F 54 15 8 Prednisone 20mg, HCQ, Leflunomide, Benlysta Prednisone 2.5mg, MTX, Sulfasalazine Patient D F 26 13 13 - Prednisone 5mg, HCQ, MMF MMF: Mycophenolate mofetil, MTX: methotrexate HCQ: hydroxychloroquinePIONEERING mRNA CELL THERAPY FOR AUTOIMMUNITY