Tscan Therapeutics, Inc. · NASDAQ:TCRX
Tscan Therapeutics — Investor Presentation (September 2025)
40 slides from Tscan Therapeutics's investor presentation, Sep 9, 2025
Slide 1: Company Presentation September 2025
Exhibit 99.1 Company Presentation September 2025
Slide 2: Disclaimers and forward-looking statements
Disclaimers and forward-looking statements This presentation and the accompanying discussion contain forward-looking TScan’s plans relating to developing and commercializing its TCR-T therapy statements within the meaning of the Private Securities Litigation Reform Act of candidates, if approved, in
Slide 3: TScan is a fully integrated, next-generation TCR-T therapy company
TScan is a fully integrated, next-generation TCR-T therapy company Clinical-stage pipeline of next-gen Promising clinical data in heme TCR-T therapies • 2 of 26 (8%) treatment-arm subjects relapsed as • HEME PROGRAM: Targeting residual disease to prevent compared to 4 of 12 (33%) control-arm relapse
Slide 4: TScan is building on the remarkable success of immunotherapy
TScan is building on the remarkable success of immunotherapy Checkpoint & TIL therapy TCR-T therapy CAR-T therapy Rejuvenating and expanding Engineering T cells to express Engineering T cells with a patient’s existing T cells natural T cell receptors a synthetic receptor Proven efficacy in solid Pro
Slide 5: Targeting the most frequent HLAs to address a broad patient population
TScan is targeting the most frequent human leukocyte antigens (HLAs) to address a broad patient population Everyone has six ~90% of people in the U.S. are class I HLAs positive for at least one of the * top six HLA types Chromosome 6 Tumor cell Mother Father % people positive A A for each HLA type C
Slide 6: Nine TCR-T candidates in clinical development
Nine TCR-T candidates in clinical development, with new TCR-Ts advancing Indications Programs (target) HLA type Discovery Lead optimization IND-enabling Phase 1 Phase 2/3 TSC-100 HLA-A*02:01 (HA-1) AML, TSC-101 HLA-A*02:01 HEMATOLOGIC MDS, (HA-2) MALIGNANCIES ALL HLA-A*03:01 TSC-102 HLA-A*01:01 (CD4
Slide 7: Heme Malignancies: TSC-100, TSC-101, TSC-102-A0301
Heme Malignancies: TSC-100, TSC-101, TSC-102-A0301 Targeting residual disease to prevent relapse in patients undergoing allogeneic HCT
Slide 8: Relapse after hematopoietic cell transplant remains an unmet need
Relapse after hematopoietic cell transplant remains an unmet need AML, MDS, some ALL is not addressed by CAR-T due to shared antigens with normal blood cells Targeting antigens 38-44% of patients relapse mismatched between Allogeneic hematopoietic within two years following patients and donors can 1
Slide 9: TSC-100 and TSC-101 are bespoke allogeneic TCR-T cell therapies
TSC-100 and TSC-101 are bespoke allogeneic TCR-T cell therapies designed to eliminate residual cancer and prevent relapse following HCT TSC-101 PATIENT Patient journey for TSC-101 (HLA-A*02:01-positive) HA-2 positive Residual Cancer HA-2 cancer Hematopoietic cell TCR-T cell cell negative transplant
Slide 10: ALLOHA Phase 1 trial for TSC-100 & TSC-101
ALLOHA , a multi-arm Phase 1 trial for TSC-100 & TSC-101 in subjects with AML, ALL, and MDS (NCT05473910) Control Arm Treatment Arms Transplant Transplant Transplant Alone + TSC-100 + TSC-101 (HA-1 positive) (HA-2 positive) Manufacturing TSC-100 or TSC-101 TSC-100 or TSC-101 apheresis Infusion 1 Inf
Slide 11: Majority of subjects are at high risk for relapse
Majority of subjects in the treatment and control arms are at high risk for relapse TSC-100 TSC-101 Any TSC Control Subjects Enrolled and Assigned 14 12 26 13 Subjects Transplanted (efficacy data cohort) 14 12 26 12 Subjects Infused (safety data cohort) 10 12 22 N/A* Median Time of Follow Up, months
Slide 12: No dose-limiting toxicities observed at all three dose levels
No dose-limiting toxicities observed at all three dose levels in subjects treated with TSC-100 or TSC-101 Planned Day of Infusion Post HCT TSC 100 TSC 101 Dose Level N=10 N=12 +21 +61 6 DL1 5×10 TCR-T cells/kg N/A 1 1 6 6 DL2 5×10 TCR-T cells/kg 5×10 TCR-T cells/kg 1 2 6 6 DL3 5×10 TCR-T cells/kg 20
Slide 13: TCR-T cells detected for over one year with increased persistence at DL3
TSC-100 and TSC-101 TCR-T cells detected for over one year with increased persistence seen at highest dose level (DL3) TSC persistence over time TSC-100 TSC-101 15 15 15 Dose Level 1 Dose Level 2 Dose Level 3 10 10 10 AUC 2.26* AUC 8.15* AUC 34.47* 5 5 5 0.2 0.2 0.2 0.1 0.1 0.1 0.0 0.0 0.0 0 50 100
Slide 14: Adverse events of special interest are low grade and manageable
Adverse events of special interest are low grade and manageable TSC-101 Any TSC TSC-100 Control Adverse Event of Special Interest* n=10 n=12 n=22 n=12 • Balanced Grade II – IV acute GvHD between Any Acute GvHD** 5 (50%) 6 (50%) 11 (50%) 4 (33%) treatment and control arms Grade II - IV 0 (0%) 2 (17%)
Slide 15: Key biomarkers serve as potential early surrogates of efficacy
Key biomarkers for residual leukemia or residual patient-derived blood cells serve as potential early surrogates of efficacy Post-transplant Patient Minimal Residual Disease Donor Chimerism (MRD) MRD+: high risk of relapse Mixed: high risk of relapse 1, 2 3 MRD-: low risk of relapse Complete: low ri
Slide 16: Complete donor chimerism achieved in all patients after initial TSC infusion
Complete donor chimerism achieved in all patients after initial TSC infusion TSC-100/TSC-101 Treatment-arm subjects Control-arm subjects Infused with TCR-T cells 101 100 101 100 101 100 101 100 101 100 101 101 101 100 100 101 100 101 100 100 100 100 C 1 C 2 C 3 C 4 C 5 C 6 C 7 C 8 C 9 C 10 C 11 C 12
Slide 17: MRD negativity achieved in all treatment-arm subjects
MRD negativity achieved in all treatment-arm subjects Pre-HCT 6 months 12 months 24 months Arm Disease MRD P-004-0001 TSC-101 DL 1 MDS p53m P-004-0004 TSC-100 DL1 T-ALL X ‡ TSC-101 DL2s AML P-004-0005 P-007-0002 TSC-100/TSC-101 infusion TSC-100 DL2 AML P-004-0006 TSC-101 DL2 B-ALL Clinical intervent
Slide 18: TCR-T infusion is associated with fewer relapses
TCR-T infusion is associated with fewer relapses Control arm 4 of 12 (33%) 0.40 0.30 0.20 Treatment arm 2 of 26 (8%) 0.10 HR = 0.28 0.00 0 45 90 135 180 225 270 315 360 405 450 495 540 585 630 675 720 765 Days post HCT Number at risk Control arm 12 11 9 9 5 4 4 4 4 2 2 1 1 1 1 1 1 1 Treatment arm 26
Slide 19: Event-free survival favors the treatment arm
Event-free survival (EFS) favors the treatment arm 1.00 Treatment arm 0.75 6 of 26 (23%) 0.50 Control arm 7 of 12 (58%) 0.25 HR = 0.30 0.00 0 60 120 180 240 300 360 420 480 540 600 Days post HCT Number at risk Control arm 12 11 7 3 2 2 2 0 0 0 0 Treatment arm 26 23 17 12 10 8 8 7 4 3 1 Cumulative nu
Slide 20: ALLOHA Phase 1 data support launch of pivotal trial in H2 25
ALLOHA Phase 1 data support launch of pivotal trial in H2 2025 • Infusions with TSC-100 and TSC-101 were well-tolerated with no DLTs and adverse events consistent with HCT • TSC-100 and TSC-101 TCR-T cells have been detected >1 year post infusion and have a clear dose- persistence relationship • 2 o
Slide 21: Heme Development Strategy
Heme Development Strategy Targeting residual disease to prevent relapse in patients undergoing allogeneic HCT
Slide 22: TSC-101 captures ~98% of HLA-A*02:01-positive patients
TSC-101 captures ~98% of HLA-A*02:01-positive patients, obviating the need for TSC-100 or a companion diagnostic 100 Almost all subjects infused to date [19/22 (86.3%)] 90 qualified for treatment with TSC-101 2.5% 80 70 60 TSC-100 TSC-101 50 (22.7%) (33.6%) 40 30 20 10 0 0 10 20 30 40 50 60 % Eligib
Slide 23: Pivotal study designed for full approval using an external control arm
Pivotal study designed for full approval using an external control arm Subjects: AML, MDS, ALL undergoing transplant with reduced intensity conditioning (RIC) Donors: Haploidentical and mismatched unrelated donors Enrollment: TSC-101 vs matched controls (1:3) Companion Diagnostic: Not needed Treatme
Slide 24: Target RFS hazard ratio of 0.60 supported by ALLOHA Phase 1 data
Target RFS hazard ratio of 0.60 is well supported by data from the ALLOHA Phase 1 study 1.00 TSC-101 1 of 12 (17%) 0.75 Control arm 5 of 12 (42%) 0.50 0.25 HR = 0.20 0.00 0 45 90 135 180 225 270 315 360 405 450 495 540 585 630 675 720 765 Days post HCT Number at risk Control arm 12 11 9 9 5 4 4 4 4
Slide 25: Increased use of RIC with haplo/MMUD donors could expand addressable market
Increased use of reduced intensity conditioning with haploidentical/MMUD donors has the potential to dramatically expand the addressable market Addressable TSC-101 patients in the U.S. and EU 6,000 KOLs anticipate increased use of KOLs also anticipate increased use of haplo and/or MMUD transplants R
Slide 26: TCRs for additional HLA types will target CD45 epitopes
TCRs for additional HLA types will target epitopes on CD45, a universal source of antigens for heme malignancies • CD45 is a lineage-specific antigen with expression in all hematopoietic cells, including HSCs • CD45 is a large protein with many well-known epitopes for high frequency HLAs • Antigen-n
Slide 27: Expansion opportunities for the heme program
Expansion opportunities for the heme program provide a way to reach over 10,000 patients in the U.S. and Europe 20,000 Addition of other heme malignancies 15,000 Addition of frail and R/R patients Addition of three TCRs for other HLA types 10,000 TSC-101 (assumes change in practice) 5,000 0 Current
Slide 28: Solid Tumors: Developing multiplex TCR-T therapy
Solid Tumors: TSC-200-A0201 TSC-204-A0201 TSC-201-B0702 TSC-204-C0702 TSC-202-A0201 TSC-204-A0101 TSC-203-A0201 Developing multiplex TCR-T therapy to overcome tumor heterogeneity
Slide 29: Multiplex TCR-T therapy addresses heterogeneity of solid tumors
Multiplex TCR-T therapy is designed to address the heterogeneity of solid tumors Many immune-rich cancers exhibit TCR-Ts against multiple targets may be target heterogeneity required to improve efficacy and durability Non-small cell lung cancer PRAME MAGE-A4 PRAME MAGE-A4 Singleplex Multiplex TCR-T
Slide 30: TScan's solution for combatting the hostile tumor microenvironment
TScan’s solution for combatting the hostile tumor microenvironment Tumor cell Enhanced TCR-T enabled TCR by TScan’s transposon- CD8a/b CD8a/b TCR based manufacturing CD4 Cytotoxic DN-TGFbRII platform Helper T cell T cell TGFb IL-2 Cytokine support • Co-deliver CD8a/b to engage helper T-cells • Co-de
Slide 31: Building the ImmunoBank of TCRs
TScan is building the ImmunoBank of TCRs to enable multiplex TCR-T cell therapy Cancer patient ImmunoBank of therapeutic TCRs Customized TCR-T therapy HLAs T cells HLA Type Profile tumor Cancer cells with different HLA types and targets • Determine target and HLA expression in patient tumor • Manufa
Slide 32: Strategically expanding the ImmunoBank
TScan is strategically expanding the ImmunoBank to enable multiplex TCR-T therapy in immune-rich solid tumors HLAs HPV16 TSC-200 MAGE-C2 TSC-201 In PLEXI-T study MAGE-A4 TSC-202 PRAME TSC-203 MAGE-A1 TSC-204 ImmunoBank 32 Targets A*02:01 A*01:01 A*03:01 B*07:02 C*07:02 A*24:02
Slide 33: PLEXI-T, a multi-arm basket Phase 1 trial in solid tumors
PLEXI-T , a multi-arm basket Phase 1 trial in subjects with solid tumors (NCT05973487) Screening Protocol Treatment Protocol Tumor testing Germline TCR-T cell manufacturing for target followed by HLA testing and infusion testing for HLA loss Patient selection Subject Tumor Infusion 1 Infusion 2 scre
Slide 34: Dose escalation scheme provides a path to multiplex TCR-T
Dose escalation scheme provides a path to multiplex TCR-T in Phase 1 TSC-200-A0201 TSC-201-B0702 TSC-202-A0201 TSC-203-A0201 TSC-204-A0201 TSC-204-C0702 TSC-204-A0101 (HPV16) (MAGE-C2) (MAGE-A4) (PRAME) (MAGE-A1) (MAGE-A1) (MAGE-A1) 0.5B 0.5B 0.5B 0.5B 0.5B 0.5B 0.5B DL1 Cleared Dosed Cleared Cleare
Slide 35: T-Plex enrollment focuses on five key indications
T-Plex enrollment focuses on five key indications with high unmet need Potential U.S. Indication patients ~63 K NSCLC Sarcoma PRAME + MAGE-A1/C2/A4 ~3 K Head & Neck ~15 K HPV16 + PRAME Cervical ~4 K HPV16 + MAGE-A1/C2/A4 Anal & Genital ~7 K • High unmet need • Evidence of T cell infiltration • Clini
Slide 36: ImmunoBank expansion has increased T-Plex eligibility
ImmunoBank expansion to seven TCRs has increased T-Plex eligibility across target indications Patients eligible for multiplex TCR-T cell therapy in PLEXI-T study 60% 60% 50% 15-60% of patients are 40% currently eligible for 40% multiplex TCR-T cell 30% 30% therapy with the 7 25% TCRs in the current
Slide 37: Autoimmunity represents an area of unmet need with few validated targets
Autoimmunity represents an exciting area of unmet need with few validated targets • Most current therapies provide general immune suppression, leading to complications (e.g., increased risk of infection) • Target-specific therapies provide a way to address the cause, rather than the symptoms, of aut
Slide 38: Steady value-generating data flow planned across clinical programs
Steady value-generating data flow planned across clinical programs H2 2025 Q1 2026 YE 2025 Launch pivotal study Two-year relapse data from Initial safety and response for TSC-101 initial patients (TSC-101) data for multiplex TCR-T File IND for TSC-102-A0301 (CD45, HLA-A*03:01) Present internal autoi
Slide 39: TScan is a fully integrated, next-generation TCR-T therapy company
TScan is a fully integrated, next-generation TCR-T therapy company Clinical-stage pipeline of next-gen Promising clinical data in heme TCR-T therapies • 2 of 26 (8%) treatment-arm subjects relapsed as • HEME PROGRAM: Targeting residual disease to prevent compared to 4 of 12 (33%) control-arm relapse
Slide 40: Thank You
THANK YOU
TScan Therapeutics — Investor Presentation (September 2025) on 6ix