Summit Therapeutics Inc. · NASDAQ:SMMT

Summit Therapeutics — ESMO 2025 Presidential Symposium

15 slides from Summit Therapeutics's conference presentation, Oct 19, 2025

  1. Slide 1: Phase III study of ivonescimab plus chemotherapy versus tislelizumab plus chemotherapy (HARMONi-6)

    Phase III study of ivonescimab plus chemotherapy versus tislelizumab plus chemotherapy as first-line treatment for advanced squamous non-small cell lung cancer (HARMONi-6) Shun Lu1, Fang Yang2, Zhou Jiang3, Longhua Sun4, Lin Wu3, Zhengxiang Han5, Yun Fan6, Yanqiu Zhao7, Xingya Li8, Haipeng Xu9, Xian

  2. Slide 2: Declaration of Interests

    Declaration of Interests Shun Lu • Received research support from AstraZeneca, Hutchison, BMS, Heng Rui, Beigene and Hansoh • Received speaker fees from Astra Zeneca, Roche, Hansoh, Hengrui Therapeutics • An advisor and consultant of Astra Zeneca, Pfizer, Hutchison MediPharma, ZaiLab,Yuhan Corporati

  3. Slide 3: Background

    Background  Several PD-(L)1 inhibitors including tislelizumab plus chemotherapy have been approved by NMPA and EMA as first-line treatment for advanced sq-NSCLC.  Ivonescimab is a bispecific antibody targeting PD-1 and VEGF. ̶ Approved in patients with non-squamous NSCLC who have experienced disea

  4. Slide 4: Study Design

    Study Design A multicenter, randomized, double-blind, parallel-controlled phase III study Ivonescimab (20 mg/kg, Q3W) Ivonescimab Key Eligibility Criteria + Carboplatin (AUC 5, Q3W) (20 mg/kg, Q3W) • Pathologically confirmed up to 24 months or + Paclitaxel (175 mg/m2, Q3W) sq-NSCLC up to 4 cycles un

  5. Slide 5: Statistical Consideration

    Statistical Consideration  Estimated sample size ̶ N=528 patients were planned to provide 86.3% power to detect an HR of 0.70 for PFS and 80% power to detect an HR of 0.73 for OS.  Hierarchical testing approach to test PFS first and OS second both at a one-sided α level of 0.025. ̶ One interim PFS

  6. Slide 6: Patient Disposition

    Patient Disposition 532 patients were randomized 266 assigned to receive 266 assigned to receive Ivonescimab plus chemotherapy Tislelizumab plus chemotherapy 1 withdrew 266 received 265 received Ivonescimab plus chemotherapy Tislelizumab plus chemotherapy 104 discontinued 131 discontinued 60 radiogr

  7. Slide 7: Baseline Characteristics

    Baseline Characteristics Ivonescimab + chemo Tislelizumab + chemo Characteristics, n(%) (N=266) (N=266) < 65 135 (50.8) 139 (52.3) Age, years ≥ 65 131 (49.2) 127 (47.7) Male 256 (96.2) 238 (89.5) Sex Female 10 (3.8) 28 (10.5) 0 42 (15.8) 42 (15.8) ECOG PS* 1 224 (84.2) 222 (83.5) Never 21 (7.9) 37 (

  8. Slide 8: Primary endpoint: PFS by IRRC

    Primary endpoint: PFS by IRRC Ivonescimab+chemo demonstrated a statistically significant improvement in PFS vs. tislelizumab+chemo with HR=0.60, representing a 4.2 months improvement in mPFS. Ivonescimab Tislelizumab + chemo + chemo (N=266) (N=266) mPFS, months 11.14 6.90 (95% CI) (9.86, NE) (5.82,

  9. Slide 9: Subgroup Analysis of PFS by IRRC

    Subgroup Analysis of PFS by IRRC • PFS benefit favored ivonescimab across all key subgroups. • Observed important baseline imbalances in the older patient subgroup (Age ≥65), such as target lesion size, brain metastases. After adjusting for these covariates, the adjusted HR for Age ≥65 was 0.69. Fav

  10. Slide 10: PFS in different PD-L1 expression Subgroups

    PFS in different PD-L1 expression Subgroups Ivonescimab showed meaningful PFS improvement over tislelizumab regardless of PD-L1 expression. PD-L1 TPS 1-49% HR 0.63 (95% CI) (0.41, 0.98) PD-L1 TPS<1% PD-L1 TPS≥1% HR 0.55 HR 0.66 (95% CI) (0.37, 0.82) (95% CI) (0.46, 0.95) PD-L1 TPS ≥50% HR 0.71 (95%

  11. Slide 11: ORR and DoR by IRRC

    ORR and DoR by IRRC Tumor response was higher and more durable in the ivonescimab arm. ORR by IRRC DoR by IRRC Any PD-L1 PD-L1 TPS<1% PD-L1 TPS≥1% 100 p=0.008 100 100 90 90 90 80 80 80 70 70 70 ORR(%) ORR(%) ORR(%) 60 60 60 50 50 50 40 75.9 40 40 80.1 66.5 69.5 70.2 30 30 61.0 30 20 20 20 10 10 10 0

  12. Slide 12: Safety Summary

    Safety Summary Ivonescimab plus chemotherapy showed a manageable safety profile in sq-NSCLC. Most common TRAEs (incidence ≥15%) Ivonescimab Tislelizumab + chemo + chemo (N=266) (N=265) TRAE 264 (99.2) 261 (98.5) Grade ≥ 3 TRAE 170 (63.9) 144 (54.3) Serious TRAE 86 (32.3) 80 (30.2) b Leading to ivone

  13. Slide 13: Immune-Related and VEGF-Related AEs

    Immune-Related and VEGF-Related AEs Ivonescimab exhibited similar irAEs to tislelizumab. Possibly VEGF-related AEs occurred more frequently in the ivonescimab arm, most of which were grade 1-2. Ivonescimab Tislelizumab Ivonescimab + chemo Tislelizumab + chemo Immune-related AEs + chemo + chemo Possi

  14. Slide 14: Conclusion

    Conclusion  Ivonescimab plus chemotherapy significantly improved PFS for advanced sq-NSCLC first-line treatment compared with tislelizumab plus chemotherapy.  mPFS: 11.14 vs. 6.90, HR=0.60 (95%CI: 0.46, 0.78), p<0.0001  PFS benefit favored ivonescimab plus chemotherapy across all key subgroup • P

  15. Slide 15: Acknowledgement

    Acknowledgement  All patients participating in the study as well as their families.  All investigators and team members involved in this trial.  Akeso Biopharma Inc. who sponsored this study. https://doi.org/10.1016/S0140-6736(25)01848-3 Published Online First at https://www.thelancet.com/journal

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