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CABA-201 Initial Clinical Data from

the RESET-Myositis & RESET-SLE Phase 1/2 Trials JUNE 2024 Exhibit 99.1

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Today's Agenda AGENDA TOPIC

SPEAKER CABA-201 Overview Steven Nichtberger, MD Chief Executive Officer Current & Investigational Treatments for Patients with Autoimmune Disease Iain McInnes, MD, FRCP, PhD, FRSE, FMedSci Vice Principal and Head of the College of Medical,

Veterinary and Life Sciences, Muirhead Chair of Medicine and Versus Arthritis Professor of Rheumatology at the University of Glasgow Initial CABA-201 Data in Myositis & Lupus David Chang, MD, MPH, FACR Chief Medical Officer Conclusions Steven

Nichtberger, MD Chief Executive Officer Q&A

4 Designed to replicate and expand on

the academic clinical data that generated interest in the field CABA-201: CD19-CAR T specifically designed for autoimmunity PK, pharmacokinetics; PD, pharmacodynamics, SAEs: serious adverse events Peng, BinghaoJ, et al. Presented at: American

Society Gene and Cell Therapy 26th Annual Meeting; 2023 May 19; Los Angeles, CA. Dai, Zhenyu, et al. Journal of Cellular Physiology. 2021;236(8): 5832-5847. Evaluated as part of CT120, a dual-CD19xCD22 CAR T product candidate under development by

Nanjing IASO Biotherapeutics, Co., Ltd. (IASO Bio). Fully human anti-CD19 binder Similar binding affinity and biologic activity to FMC63, with binding to the same epitopes1,2 Safety data in ~20 oncology patients evaluated and reported by IASO as

part of a dual-CAR3 4-1BB costimulatory domain Same domain as used in academic studies CD3-zeta signaling domain CABA-201 CABA-201 designed to optimize the potential safety and efficacy of CD19-CAR T for patients with autoimmune disease Key

Questions for RESET Phase 1/2 Studies Safety of CABA-201 CABA-201 AE profile CRS, ICANS, SAEs Dose selection 1 x 106 cells/kg PK - CAR T persistence PD - B cell depletion Autoantibody reduction Clinical outcomes

Innovative and scalable clinical

strategy with potential for accelerated development path CABA-201 pipeline targeting a broad range of autoimmune diseases RESET - REstoring SElf-Tolerance; IMNM - Immune-mediated necrotizing myopathy; SLE - Systemic lupus

erythematosus; Ab - Antibody; AChR - Acetylcholine receptor; gMG - Generalized myasthenia gravis, PV - Pemphigus vulgaris FDA Fast Track Designation received in dermatomyositis, SLE and lupus nephritis, systemic sclerosis,

mucosal pemphigus vulgaris, and MuSK-Ab positive MG. 1. Sub-study incorporated into DesCAARTes study. 2. Data cut-off as of 28 May 2024. Program Trial Preclinical Phase 1/2 Pivotal CABA-201 4-1BB CD19-CAR T RESET-Myositis CARTA

Chimeric Antigen Receptor T cells for Autoimmunity RESET-SLE RESET-SSc RESET-MG RESET-PV Sub-study1 Dermatomyositis Anti-synthetase syndrome IMNM Lupus Nephritis Non-Renal SLE Skin + Organ Cohort AChR-Ab neg. gMG AChR-Ab

pos. gMG Skin Cohort FTD Mucocutaneous & mucosal pemphigus vulgaris Juvenile Myositis Clinical & translational data2 support the selected single dose of CABA-201 at 1 x 106 cells/kg Rheumatology Neurology Dermatology Contains cohort(s)

without preconditioning Pediatric Indication

Acceleration in enrollment anticipated

in 2H24 with initial CABA-201 data & engaged clinical investigators Sites actively recruiting patients in the RESETTM clinical program1 5 patients enrolled across RESET-SLETM & RESET-MyositisTM, with 3 patients enrolled over the last 2

months 18 actively recruiting clinical sites in the U.S. across the RESETTM studies RESET-SScTM and RESET-MGTM trials now open for enrollment 1. As of June 12, 2024. SLE sites Myositis sites SSc sites MG sites

Current & Investigational

Treatments for Patients with Autoimmune Diseases

Broad immunosuppression and chronic

administration often required to achieve partial, transient responses Current therapies for autoimmunity do not achieve drug-free remission (Hematopoietic stem cell transplant has been shown to be curative in systemic sclerosis but has increased

mortality in the first year6) There is a need for durable, effective and safe therapies that reestablish immune tolerance to eliminate the need for long-term therapy5,6 Khoo T, et al. Nat Rev Rheumatol. 2023;19(11):695-712. Octapharma. Accessed June

10, 2024. Hoover PJ, Costenbader KH. Kidney Int. 2016;90(3):487-92. High Unmet Clinical Need in SLE & Myositis Potential for life-threatening complications ~40% of patients with SLE develop LN3,4 ~25% risk of death or ESRD within 10y Incomplete

responses despite chronic therapy High mortality due to lung & cardiac involvement1 Only FDA & EMA-approved therapy is IVIg in DM2 Many patients remain refractory to standard of care therapies - particularly high unmet need in IMNM1

Lupus Current Therapies in Autoimmunity Broad immunosuppression Modest & inconsistent clinical responses Chronic therapy requirements Hahn BH, et al. Arthritis Care Res (Hoboken). 2012; 64(6): 797-808. Rosenblum MD, et al. Sci Transl Med.

2012;4(125):125sr1. Swart J, et al. Nat Rev Rheumatol. 2017;13:244-256. Myositis

Potential for treatment paradigm to

evolve in autoimmunity CAR T therapy has the potential to provide drug-free, durable & reliable responses Promising clinical responses reported in 15 patients with an academic 4-1BB CD19-CAR T1-3 100% Clinical responses in SLE, myositis, SSc off

immunosuppressive therapies 2+ years SLE drug-free remission with single infusion of CD19-CAR T3 Within 7 months Repopulation of na ve B cells post-infusion <7% Rate of CRS more severe than fever (1/15) Rate of ICANS (1/15) What are the

clinical outcomes with autologous 4-1BB CD19-CAR T cell therapy? CRS - Cytokine release syndrome; ICANS - Immune effector cell-associated neurotoxicity syndrome M ller, Fabian, et al. "CD19 CAR T-Cell Therapy in Autoimmune

Disease-A Case Series with Follow-up." New England Journal of Medicine 390.8 (2024): 687-700. The construct utilized in these studies has a similar design to CABA-201, sharing the 4-1BB costimulatory domain, but is a different construct. It

has been publicly reported that one idiopathic inflammatory myopathy subject in this academic study had a reoccurrence of disease following ~18 months of clinical remission. How is CAR T cell therapy designed to reset the immune system? A

living drug' potentially enabling complete B cell depletion in the blood, tissues, lymph nodes & secondary lymphoid organs While autologous CD19-CAR T has potential to deliver drug-free, durable & reliable responses, multiple

other therapeutic modalities may find a role within the future treatment paradigm

Initial CABA-201 Data in Myositis

Phase 1/2 Myositis Study for

CABA-201 CY, cyclophosphamide; EULAR/ACR, European Alliance of Associations for Rheumatology/America College of Rheumatology; FLU, fludarabine; HSCT, hematopoietic stem cell transplantation. TIS, Total Improvement Score. Juvenile idiopathic

inflammatory myopathy (JIIM, juvenile myositis) cohort recently incorporated into trial Key inclusion criteria Age 18 and 75 with a definite or probable clinical diagnosis of IIM (2017 EULAR/ACR classification criteria) Diagnosis of

antisynthetase syndrome (ASyS), dermatomyositis (DM), or immune-mediated necrotizing myopathy (IMNM) based on presence of serum myositis-specific antibodies Evidence of active disease despite prior or current treatment with standard of care Key

exclusion criteria Cancer-associated myositis Significant lung or cardiac impairment B cell-depleting agent within prior ~6 months Previous CAR T cell therapy and/or HSCT Screening ASyS n 6 IMNM cohort n 6 DM cohort n 6 Day 1

Day 29 Follow-up through year 3 Leukapheresis and CABA-201 production Preconditioning with FLU and CY Single infusion of CABA-201 (1 106 cells/kg) Primary endpoint: Incidence and severity of adverse events Secondary endpoints: TIS CK / muscle

enzymes Myositis-specific autoantibody levels Adverse events PK / PD analysis

Phase 1/2 Lupus Study for CABA-201

ANA, antinuclear antibody; SLEDAI-2K, Safety of Estrogens in Lupus Erythematosus National Assessment Systemic Lupus Erythematosus Disease Activity Index-2K. Key inclusion criteria Age 18 to 65 with an SLE diagnosis (2019 EULAR/ACR

classification criteria) ANA+ or anti-dsDNA+ at screening For SLE (non-renal) cohort: active, moderate to severe SLE, SLEDAI 2K 8 despite standard therapy For Lupus Nephritis cohort: active, biopsy-proven LN class III or IV, class V

Key exclusion criteria B cell-depleting agent within prior ~6 months Previous CAR T cell therapy and/or HSCT Presence of kidney disease other than LN Screening LN cohort n 6 Day 1 Day 29 Follow-up through year 3 Leukapheresis and CABA-201

production Preconditioning with FLU and CY Single infusion of CABA-201 (1 106 cells/kg) Primary endpoint: Incidence and severity of adverse events SLE non-renal cohort n 6 Secondary endpoints: SLE disease activity (e.g., SLEDAI-2K)

Complete renal response Adverse events PK / PD analysis Biomarker analyses

Time to B cell repopulation B cell

phenotype3 Autoantibody changes Durability of clinical activity Rate & severity of infection Chronic maintenance / concomitant medications, if any Up to 12+ months Translational & clinical parameters inform framework to evaluate advanced

modalities in autoimmunity Metrics to assess outcomes of B cell depletion in autoimmunity Indicates data being presented for either or both of the first two patients in the RESET clinical program. Illustrative graphic, adapted from Taubmann, J., et

al. "OP0141 Long Term Safety and Efficacy Of CAR-T Cell Treatment in Refractory SLE-Data from the First Seven Patients." (2023): 93-94. M ller, Fabian, et al. "CD19 CAR T-Cell Therapy in Autoimmune Disease-A Case Series with Follow-up."

New England Journal of Medicine 390.8 (2024): 687-700. Flow phenotyping data; confirmatory analyses ongoing. Following treatment with autologous CD19-CAR T, 6 pts with 12+ mo. of drug-free remission, as reported by Erlangen group2 Infusion 1 mo. 3