SystImmune, Inc. to Present New Phase 3 Data on Iza-bren (izalontamab brengitecan) in EGFR-mutated NSCLC, HR+ Breast Cancer, and Phase 2 Data in Head and Neck Cancer at ESMO 2026

- Four abstracts accepted for presentation at European Society for Medical Oncology (ESMO) 2026 demonstrate the breadth of clinical development across multiple tumor types and treatment settings

BOTHELL, Wash., Oct. 19, 2026 /PRNewswire/ -- SystImmune, Inc. (SystImmune), a clinical-stage biotechnology company, today announced that four abstracts for iza-bren (izalontamab brengitecan), a potentially first-in-class EGFRxHER3 bispecific antibody drug conjugate (ADC), will be presented at the European Society for Medical Oncology (ESMO) Congress 2026 taking place October 23-27 in Madrid, Spain. Iza-bren is being developed under a license and collaboration agreement by and between SystImmune and Bristol Myers Squibb.

The data being presented at ESMO highlights the continued clinical development of iza-bren across multiple tumor types and treatment settings including:

• Late-breaking data from a randomized Phase III study evaluating iza-bren versus platinum-based chemotherapy in Chinese patients with EGFR-mutant non-squamous NSCLC after progression on a third-generation EGFR TKI, addressing the limited treatment options available to this previously treated population
• Late-breaking data from a randomized Phase III study evaluating iza-bren versus physician's choice chemotherapy in Chinese patients with previously treated unresectable locally advanced or metastatic HR+/HER2- breast cancer, who have developed resistance to prior endocrine therapy and CDK4/6 inhibitors
• Results from a Phase II study of iza-bren in combination with pembrolizumab in Chinese patients with treatment-naive recurrent or metastatic head and neck squamous cell carcinoma, exploring the potential of combining a first-in-class bispecific ADC with immunotherapy
• Results from a Phase II study of iza-bren in combination with osimertinib in Chinese patients with EGFR-mutant locally advanced or metastatic NSCLC in the first line setting, investigating dual-targeted combination strategies in this patient population

"The data presented at ESMO 2026 demonstrates the expanding clinical profile of iza-bren across multiple tumor types and treatment paradigms," said Jonathan Cheng, M.D., Chief Medical Officer of SystImmune. "We are pleased to share these presentations, which represent important milestones in our ongoing global development program. The breadth of data being presented, from our two registrational studies to our exploration of iza-bren in combination regimens, underscores our commitment to understanding the full therapeutic potential of iza-bren for patients with difficult-to-treat cancers."

Details of the presentations at ESMO are below:
‍‍PANKU-Breast01: Randomized Phase III Study of Izalontamab Brengitecan (iza-bren) in Previously Treated Unresectable Locally Advanced or Metastatic HR+/HER2- Breast Cancer (BC)
Trial Reference: BL-B01D1-306 (NCT06343948), China
Session Title: Proffered paper session: Breast cancer, early and advanced stage
Presentation Number: LBA50
Speaker: Bo Lan (Beijing, China)
Session Date & Time: Friday, October 23^rd, 2026, 13:30-15:00 CEST

PANKU-Lung01: Randomized Phase III Study of Izalontamab Brengitecan (iza-bren) in EGFR-Mutant Non-squamous Non‑Small Cell Lung Cancer (NSCLC) After Progression on a Third Generation EGFR TKI
Trial Reference: BL-B01D1-301 (NCT06382116), China
Session Title: Proffered paper session: NSCLC, metastatic
Presentation Number: LBA71
Speaker: Li Zhang (Guangzhou, China)
Session Date & Time: Monday, October 26^th, 2026, 08:30-10:00 CET

Phase II Study of Izalontamab Brengitecan (iza-bren) Plus Pembrolizumab in Patients with Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma (R/M HNSCC)
Trial Reference: BL-B01D1-204-02 (NCT06437522), China
Session Title: Rapid Oral: Head and Neck Cancer
Presentation Number: 1542RO
Speaker: Dongmei Ji (Shanghai, China)
Session Date & Time: Sunday, October 25, 2026, 14:45-16:15 CET

Phase II Study of Izalontamab Brengitecan (iza-bren) plus Osimertinib in Patients with EGFR Mutant Locally Advanced or Metastatic Non-Small Cell Lung Cancer (NSCLC)
Trial Reference: BL-B01D1-203 (NCT05880706), China 
Session Title: Poster Session: NSCLC Locally Advanced
Presentation Number: 2575P
Speaker: Fei Zhou (Shanghai, China)
Session Date & Time: Monday, October 26, 2026, 12:00-12:45 CET

About izalontamab brengitecan (iza-bren)

Izalontamab brengitecan (iza-bren, BL-B01D1) is a bispecific antibody-drug conjugate (ADC) that targets both EGFR and/or HER3, antigens that are highly expressed in various epithelial cancers and are known to be associated with cancer cell proliferation and survival. Upon target binding and internalization, iza-bren's therapeutic novel Topo1i payload is released, causing cytotoxic stress that leads to cancer cell death. Iza-bren's dual mechanism of action also blocks EGFR and HER3 signals to cancer cells, reducing proliferation and survival signals. Iza-bren is being developed under a license and collaboration agreement by and between SystImmune and Bristol Myers Squibb.

About SystImmune

SystImmune is a clinical-stage biotechnology company located in Bothell, WA. It specializes in developing innovative cancer treatments using its established drug development platforms, focusing on bi-specific, multi-specific antibodies, and antibody-drug conjugates (ADCs). SystImmune has several assets in various stages of clinical trials for solid tumor and hematologic indications. Alongside ongoing clinical trials, SystImmune has a robust preclinical pipeline of potential cancer therapeutics in the discovery or IND-enabling stages, representing cutting-edge biologics development.

Forward-Looking Statements

This press release contains forward-looking statements, including statements regarding the potential clinical benefits of iza-bren, the timing and outcomes of regulatory interactions, and the future development and commercialization of iza-bren. Forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially. SystImmune undertakes no obligation to update any forward-looking statements contained herein, except as required by law.

SOURCE SystImmune, Inc.