SystImmune, Inc. to Present New iza-bren (izalontamab brengitecan) Data in Non-Small Cell Lung Cancer at WCLC Congress 2025

• Safety & efficacy of iza-bren, an EGFRxHER3 bispecific topoisomerase inhibitor- based antibody-drug conjugate (ADC), in patients with EGFR mutated Non-Small Cell Lung Cancer (NSCLC), both as monotherapy and in combination with Osimertinib will be presented

REDMOND, Wash., Sept. 2, 2025 /PRNewswire/ -- SystImmune, Inc. (SystImmune), a clinical-stage biotechnology company, today announced that two abstracts for iza-bren (izalontamab brengitecan), a potentially first-in-class EGFRxHER3 bispecific antibody drug conjugate (ADC), will be presented at the World Conference on Lung Cancer (WCLC) 2025 Annual Meeting taking place September 6 – 9 in Barcelona, Spain. Iza-bren is jointly developed by SystImmune and Bristol Myers Squibb under a collaboration and exclusive license agreement in territories outside of China.

The safety and efficacy results of iza-bren as a monotherapy and in combination with Osimertinib in patients with advanced stages of EGFR mutated Non-Small Cell Lung Cancer will be presented at WCLC. The data highlights the continued progress of iza-bren clinical development and builds upon the previously reported clinical activity in lung, breast, and bladder cancer patients at ASCO, ESMO, and SABCS in 2023, 2024 and 2025.

"These data further enhance our confidence in iza-bren's clinical activity across a wide range of tumors," said Jonathan Cheng, M.D., Chief Medical Officer of SystImmune. "We are particularly excited by the potential of iza-bren in combination with osimertinib as a first-line treatment for EGFR-mutated NSCLC. This approach may offer the opportunity for deeper and more durable responses in newly diagnosed patients, and we remain committed to advancing its development to address unmet needs in lung cancer."

Details of the presentations at WCLC are below:
Phase I/II Study of iza-bren (BL-B01D1) as Monotherapy in Patients with pre-treated Locally Advanced or Metastatic EGFR Mutated NSCLC
Session Title: OA10 – Optimizing Systemic Therapy; Bridging New and Old
Presentation: OA10.03
Speaker: Wenfeng Fang (Guangzhou, China)
Session Date & Time: Monday, September 8^th, 2025, 3:30 PM-4:45 PM CEST

Phase II Study of iza-bren (BL-B01D1) Combo with Osimertinib in EGFR Mutated Locally Advanced or Metastatic NSCLC Patients
Session Title: OA10 – Optimizing Systemic Therapy; Bridging New and Old
Presentation: OA10.04
Speaker: Fei Zhou (Zhengzhou, China)
Session Date & Time: Monday, September 8^th, 2025, 3:30 PM-4:45 PM CEST

About iza-bren
SystImmune, in collaboration with BMS outside of China, is developing iza-bren (BL-B01D1), a bispecific antibody-drug conjugate (ADC) that targets both EGFR and HER3 targets that are highly expressed in various epithelial cancers and are known to be associated with cancer cell proliferation and survival. Iza-bren's dual mechanism of action blocks EGFR and HER3 signals to cancer cells, reducing proliferation and survival signals. In addition, upon antibody mediated internalization, iza-bren's therapeutic payload is released causing genotoxic stress that leads to cancer cell death.

About SystImmune
SystImmune is a clinical-stage biopharmaceutical company located in Redmond, 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
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For additional information about the company, please visit https://systimmune.com/.

SOURCE SystImmune, Inc.