NovaBridge Biosciences · NASDAQ:NBP
NovaBridge Biosciences — I-Mab — ESMO GI 2025
15 slides from NovaBridge Biosciences's conference presentation, Oct 23, 2025
Slide 1: Updated Safety, Efficacy and Biomarker Analysis from the Phase I Monotherapy Study of Givastomig
Updated Safety, Efficacy and Biomarker Analysis from the Phase I Monotherapy Study of Givastomig, a Novel Claudin 18.2/4-1BB Bispecific Antibody, in Claudin 18.2 Positive Advanced Gastroesophageal Carcinoma (GEC) Samuel J. Klempner, MD Massachusetts General Hospital, Boston, MA, United States
Slide 2: Disclosure Information
Disclosure Information Samuel J. Klempner I have the following relevant financial relationships to disclose: Employee of: Massachusetts General Hospital Consultant for: Bristol-Myers Squibb, Merck, Astellas, Daiichi-Sankyo, Natera, Novartis, AstraZeneca, Mersana, Sanofi-Aventis, Amgen, Boehringer-In
Slide 3: Background
Shen JITC 2024 Ku CCR 2025 Background Givastomig, a CLDN18.2 x 4-1BB bispecific antibody, exerts anti-tumor activity through CLDN18.2-based, tumor-directed T-cell activation.1 NCT04900818 is an open label, first-in-human, phase 1 study of givastomig monotherapy in patients with advanced solid tumors
Slide 4: Phase 1 Study Design
Multi-center, dose-escalation and expansion phase Ib study Monotherapy: US and China. Combination: US only Escalation via BOIN design with at least four subjects per dose Phase 1 Study Design BOIN = Bayesian Optimal Interval Design CLDN18.2-positive = membrane intensity ≥1+ on ≥1% of tumor cells Dos
Slide 5: Phase 1 Study Design
Multi-center, dose-escalation and expansion phase Ib study Monotherapy: US and China. Combination: US only Escalation via BOIN design with at least four subjects per dose Phase 1 Study Design BOIN = Bayesian Optimal Interval Design CLDN18.2-positive = membrane intensity ≥1+ on ≥1% of tumor cells Dos
Slide 6: Baseline Characteristics
45 patients with CLDN18.2+ GEC were enrolled into cohorts of escalating doses of givastomig 5*-15 mg/kg Q2W, and 18 mg/kg Q3W. Patients had received a median of 3 prior therapies, including 74% with prior programmed death-(ligand) 1 inhibitor. CLDN18.2 SP455 assay Baseline Characteristics * 4-1BB in
Slide 7: Safety
No dose-limiting toxicities were observed up to 15mg/kg Q2W and 18 mg/kg Q3W. Maximum-tolerated-dose was not reached. Grade ≥3 TRAE occurred in 33% of patients. One patient experienced a grade 4 platelet count decreased*. Grade 3 TRAE occurring in more than one patient were anemia (9%), lymphocyte c
Slide 8: Treatment Related Adverse Events
Treatment Related Adverse Events Common TRAE in ≥ 10% of subjects (n=45) Preferred Term Grade 1-2 n (%) Grade 3 n (%) Grade 4 n (%) All Grades n (%) Anaemia 8 (18%) 4 (9%) 0 (0%) 12 (27%) WBC decreased 7 (16%) 3 (7%) 0 (0%) 10 (22%) Nausea 8 (18%) 1 (2%) 0 (0%) 9 (20%) ALT increased 6 (13%) 1 (2%) 0
Slide 9: Swimmer Plot & Efficacy Summary
Swimmer Plot & Efficacy Summary 5 mg/kg (n=7) 8 mg/kg (n=5) 12 mg/kg (n=21) 15 mg/kg (n=6) 18 mg/kg Q3W (n=6) All (n=45) Confirmed ORR n (%) 1 (14%) 1 (20%) 4 (19%) 0 2 (33%) 8 (18%) 95%CI (0.2, 33.9) (0.3, 44.5) (2.7, 22.6) (0.0, 45.9) (2.1, 48.4) (3.9, 16.8) DCR (PR + SD) n (%) 2 (28.6%) 2 (40.0%)
Slide 10: Waterfall
NA = not available red font = CPS <5 and CLDN <75% Waterfall Data cut-off: August 27, 2025
Slide 11: CLDN18.2 Expression vs. Clinical Efficacy
CLDN18.2 Expression vs. Clinical Efficacy CLDN18.2 N ORR DCR mPFS (mo., 95% CI) mOS (mo., 95% CI) PFS Hazard Ratio (High vs. Low) OS Hazard Ratio (High vs. Low) Low High Low High Low High Low High Low High 10% 2+/3+ 4 41 25% 17% 50% 49% 5.4 (1.7-NA) 2.8 (1.7-3.9) 9.0 (3.2, NA) 7.5 (5.0-11.9) 1.5 (0.
Slide 12: CLDN18.2 Expression vs. Clinical Efficacy
No statistically significant differences in ORR, DCR, PFS, or OS between CLDN18.2-high and CLDN18.2-low groups, using a variety of cutoffs CLDN18.2 Expression vs. Clinical Efficacy CLDN18.2 Expression Cutoff CLDN18.2-Low (< Cutoff) CLDN18.2-High (≥ Cutoff) PFS Hazard Ratio (High vs. Low) OS Hazard R
Slide 13: CLDN18.2 Expression vs. PFS and OS
No statistically significant differences in PFS or OS between CLDN18.2-high (defined as ≥ 75% of 2+/3+, n=21) and CLDN18.2-low (n=24) CLDN18.2 Expression vs. PFS and OS Data cut-off: August 27, 2025 13
Slide 14: Givastomig 1L Combination Escalation
Givastomig 1L Combination Escalation Data cut-off: May 15, 2025 Presented at ESMO GI 2025 14
Slide 15: Conclusions
With over a year of additional follow up, givastomig continues to be well tolerated up to 15 mg/kg Q2W and 18 mg/kg Q3W and continues to show encouraging monotherapy activity in heavily pre-treated GEC patients with a wide range of CLDN18.2 expression (confirmed ORR 18%). There was no statistically