Slide 1: Corporate Presentation June 2025
NASDAQ: NXTC SIM0505 LNCB74 J U N E 2 0 2 5 Corporate Presentation
Slide 2: Forward-Looking Statements
Forward-Looking Statements 2 To the extent that statements contained in this presentation are not descriptions of historical facts, they may be deemed to be forward-looking statements under the Private Securities Litigation Reform Act of 1995. These statements are based on current expectations, fore
Slide 3: Developing 2 Differentiated ADCs
3 Developing 2 Differentiated ADCs RUNWAY • LNCB74 and SIM0505 Ph1 readouts expected in 1H 2026 • Mid-2026 • Leverage existing infrastructure to initiate US trial in 3Q 2025 • Combine China & US Ph1 data for fast and definitive POC OUR APPROACH NEW OPPORTUNITY • Global rights (ex-China) for Simcere
Slide 4: Novel ADCs: Designed for Multi-Pronged Approach to Improve Efficacy
Novel ADCs: Designed for Multi-Pronged Approach to Improve Efficacy 4 TARGETS PAYLOADS B7-H4 Tubulin Inhibitor LNCB74 CDH6 Topoisomerase 1 Inhibitor SIM0505 •Tumor Eradication •Overcoming Resistance •Increasing Durability •Cancer Types •Limited Treatment Options •Aging Population •Medical Costs
Slide 5: Ongoing Ph1 Trials with Differentiated ADCs
Ongoing Ph1 Trials with Differentiated ADCs 5 PROGRAMS TARGET PAYLOAD PRECLINICAL PHASE 1 LNCB74 B7-H4 MMAE SIM0505 CDH6 TOPOi Co-development with Breast, Ovarian, Endometrial Ovarian, Lung, Renal
Slide 6: Strategic Partnership: Global License from Simcere Zaiming
6 STRATEGIC PARTNERSHIP Global license (ex China) from Simcere Zaiming DIFFERENTIATED ADC • Proprietary CPT116 TOPOi • Unique epitope & high affinity PH1 CLINICAL ASSET • Clinical trial ongoing in China • NXTC to initiate US Ph1 3Q 2025 • Combine US and China data for speed to POC MULTIPLE INDICATIO
Slide 7: SIM0505 is a Differentiated CDH6 TOPOi ADC
SIM0505 is a Differentiated CDH6 TOPOi ADC 7 Payload CPT116 (TOPOi) GGFG Linker CDH6 mAb DAR 8.0 Cysteine conjugation Gly-Gly-Phe-Gly Provides Tumor-Specific Cleavage Unique Binding Epitope with Increased Affinity High Systemic Clearance for Reduced Toxicity Linker Potent Cytotoxicity with Anticipat
Slide 8: CDH6 Competition and Differentiation
CDH6 Competition and Differentiation 8 Key Features SIM0505 DS-6000 CUSP06 HS-20124 QLS-5133 ADC Design • CDH6 mAb (EC1) • CDH6 mAb (EC3) • CDH6 mAb (EC3) • CDH6 mAb low affinity • CDH6 mAb (high affinity) • GGFG cleavable linker • GGFG cleavable linker • Dipetide-T1000-e platform • Tetrapeptide cle
Slide 9: SIM0505 Antibody Binding Differentiation
SIM0505 Antibody Binding Differentiation 9 mAb Human CDH6 Cyno CDH6 Rat CDH6 Mouse CDH6 mAb003-H2L3 0.028 0.029 0.025 0.026 DS-H01L02 0.454 0.148 No binding No binding EC50 (nM) mAb003-H2L3: SIM0505 mAb intermediate Comparator: Analog of DS-H01L02 (DS-6000 mAb intermediate) -5 -4 -3 -2 -1 0 1 2 3 0
Slide 10: SIM0505 Ovarian Cancer Cell Line Binding Differentiation
SIM0505 Ovarian Cancer Cell Line Binding Differentiation 10 -3 -2 -1 0 1 2 3 0 2000 4000 6000 8000 10000 12000 OVCAR3 Ab Conc Log(nM) Median MFI SIM0505 Comparator Control -3 -2 -1 0 1 2 3 0 2000 4000 6000 8000 10000 12000 PA-1 Conc (nM) Median MFI SIM0505 Comparator Control Courtesy of Simcere Zaim
Slide 11: SIM0505 Active in Ovarian and Renal Tumor Models
SIM0505 Active in Ovarian and Renal Tumor Models 11 0 5 8 12 16 19 22 27 0 200 400 600 800 1000 OVCAR3 CDX Days after treatment Tumor volume (mm 3 ) No Treatment SIM0505 (3 mg/kg) Comparator (3 mg/kg) 0 4 8 11 15 18 22 25 0 200 400 600 800 1000 PA-1 CDX Days after treatment Tumor volume (mm 3 ) No T
Slide 12: Accelerating SIM0505 Global Development
Accelerating SIM0505 Global Development Expected Data Readout POC 1H 2026 Cohort 1 Cohort 2 Cohort 3 Cohort 4 Backfill Cohorts ✓ 12 Dose Expansion • 6 dose cohorts • Regimen Q3W • N=54 subjects • 3 dose cohorts • 2 tumor types • N=120 subjects • Pre & on treatment biopsies Patient selection strategy
Slide 13: SIM0505 Phase 1 Initial Clinical Data Summary
SIM0505 Phase 1 Initial Clinical Data Summary (as of April 16, 2025) 13 • 5 patients to date ̶ Dose level 1 (1.6 mg/kg): 3 ̶ Dose level 2 (3.2 mg/kg): 2 • Tumor types ̶ High-grade serous ovarian cancer: 3 ̶ Serous endometrial carcinoma: 1 ̶ Poorly differentiated endometroid adenocarcinoma: 1 • Dose
Slide 14: Expanding in NSCLC
EGFRwt, CDH6 H-score 250 EGFRwt, CDH6 H-score 190 EGFRwt/ALKm, CDH6 H-score 213 Expanding in NSCLC 14 Courtesy of Simcere Zaiming *Primary antibody: Caherin-6 (D3T3I, Rabbit mAb, CST; Leica BOND III platform) EGFRwt (H-score 250) EGFRwt (H-score 190) EGFRwt/ALKm (H-score 213) Cancer Stage Sample Typ
Slide 15: Opportunity to Develop Differentiated CDH6 ADC Therapeutic
POTENTIAL FOR IMPROVED SAFETY & EFFICACY Opportunity to Develop Differentiated CDH6 ADC Therapeutic 15 CDH6 ADC ONGOING PH1 TRIAL IN CHINA PH1 CLINICAL POC EXPECTED 1H 2026 SIM0505
Slide 16: LNCB74 B7-H4 ADC
16 LNCB74 B7-H4 ADC DIFFERENTIATED ADC Unique antibody linker STRATEGIC PARTNERSHIP 50/50 co-development partnership with LigaChem Biosciences MULTIPLE INDICATIONS Breast, Ovarian, Endometrial PH1 CLINICAL ASSET • US clinical trial ongoing • CLIA validated IHC biomarker assay
Slide 17: LNCB74 is a Differentiated Anti-B7-H4 MMAE ADC
LNCB74 is a Differentiated Anti-B7-H4 MMAE ADC Fc Modification Protects immune cells Tumor Selectivity Glucuronidase cleavable linker provides improved safety & increased efficacy 17 MMAE DAR 4 Improves targeted release and safety Antibody Linker Payload STRUCTURAL DIFFERENTIATION
Slide 18: LNCB74 Uses Differentiating Glucuronidase Linker
LNCB74 Uses Differentiating Glucuronidase Linker Designed for Improved Safety & Increased Efficacy 18 Bloodstream Tissues Cancer Cell Bystander Effect Linker Glucuronidase cleavable Payload Tubulin inhibitor Conjugation Site Specific DAR 4 •Efficient release of toxin •Higher concentration Stable Pot
Slide 19: Key Differentiating Features of Glucuronidase Linkers
Key Differentiating Features of Glucuronidase Linkers 19 Time (Hours) Relative Toxin Concentration per Cancer Cell 100% Val-cit Linker Glucuronidase Linker Control ADC Glucuronidase Linker Val-cit Linker Site specific attachment to mAb □ Non-specific attachment to mAb Highly stable linkage □ Uns
Slide 20: LNCB74 Showed Potent Anti-Tumor Activity in CDX and PDX Models
20 LNCB74 Showed Potent Anti-Tumor Activity in CDX and PDX Models OVARIAN (OVCAR-3-B7-H4-OE) Days from Treatment Initiation Mean Volume (mm3) +/- SEM TNBC (CTG-0012) Mean Volume (mm3) +/- SEM Days from Treatment Initiation BREAST (ZR-75-1) Days from Treatment Initiation Mean Tumor Volume (mm3) +/- S
Slide 21: B7-H4 Competition and Differentiation
B7-H4 Competition and Differentiation Key Features LNCB74 XMT-1660 HS-20089 AZD8205 DB-1312 / BG-C9074 ADC Design • B7-H4 mAb • B7-H4 mAb • B7-H4 mAb • B7-H4 mAb • B7-H4 mAb • Glucuronidase cleavable linker • Protease cleavable linker • Protease cleavable linker • Pegylated Val-Ala cleavable linker
Slide 22: LNCB74 is More Effective than Comparator B7-H4-MMAE
LNCB74 is More Effective than Comparator B7-H4-MMAE 22 0 10 20 30 40 0 500 1000 1500 2000 No Treatment LNCB74 (3 mg/kg) Comparator (3 mg/kg) 0 10 20 30 40 0 500 1000 1500 2000 No Treatment Comparator (4.5 mg/kg) LNCB74 (4.5 mg/kg) 0 10 20 30 40 0 500 1000 1500 2000 No Treatment LNCB74 (6 mg/kg) Comp
Slide 23: Advancing LNCB74 Development
Advancing LNCB74 Development Expected Data Readout POC 1H 2026 Cohort 1 Cohort 2 Cohort 3 Cohort 4 Backfill Cohorts ✓ ✓ 23 Dose Expansion • 4 dose cohorts • Regimen Q3W • N=65 subjects • 2 dose cohorts • 2 tumor types • N=80 subjects • Pre & on treatment biopsies Patient selection strategy Patient s
Slide 24: Opportunity to Develop Differentiated B7-H4 ADC Therapeutic
IMPROVED SAFETY & INCREASED EFFICACY Opportunity to Develop Differentiated B7-H4 ADC Therapeutic 24 B7-H4 ADC UNMET NEED IN BREAST & GYNECOLOGICAL CANCERS PATIENT SELECTION STRATEGY
Slide 25: 2026 Expected Milestones & Deliverables
25 2026 Expected Milestones & Deliverables • LNCB74 (B7-H4) POC in 1H 2026 (Breast, Ovarian, Endometrial) • SIM0505 (CDH6) POC in 1H 2026 (Ovarian, Lung, Renal) 2026 CLINICAL POC PHASE 1 CLINICAL ASSETS • B7-H4 and CDH6 ADCs • Differentiated ADCs RUNWAY • Mid-2026