• First regulatory approval for iza-bren (BL-B01D1), a first-in-class EGFR×HER3 bispecific antibody-drug conjugate (ADC)
• Represents an important new treatment option for patients with recurrent or metastatic nasopharyngeal carcinoma (NPC) who have progressed following prior platinum-based chemotherapy and PD-1/PD-L1 inhibitor therapy

REDMOND, Wash., June 22, 2026 /PRNewswire/ -- SystImmune Inc. (SystImmune), a clinical-stage biotechnology company, today announced that its parent company, Sichuan Biokin Pharmaceutical Co., Ltd. (Biokin), has received regulatory approval from the Center for Drug Evaluation (CDE) of the China National Medical Products Administration (NMPA) for iza-bren (BL-B01D1) for the treatment of patients with recurrent or metastatic nasopharyngeal carcinoma (NPC) who have progressed following prior platinum-based chemotherapy and PD-1/PD-L1 inhibitor therapy. This approval marks the first regulatory approval for iza-bren and represents a significant milestone in the development of SystImmune's proprietary bispecific antibody-drug conjugate platform.

The approval is based on results from the pivotal Phase III BL-B01D1-303 study (NCT06118333). In this study, Iza-bren demonstrated a BICR-assessed confirmed ORR of 54.6% vs. 27.0% for chemotherapy (Odds Ratio 3.3; 95% confidence interval 1.9-5.8; p<0.0001). Median duration of response (DoR) was 8.5 months for iza-bren versus 4.8 months for physician's choice of chemotherapy (Hazard ratio 0.43; 95% CI 0.22 to 0.83). Furthermore, median progression-free survival (PFS) was 8.38 months for iza-bren compared to 4.34 months for chemotherapy (hazard ratio of 0.44; 95% confidence interval 0.32-0.62). At the time of this analysis, the overall survival (OS) data were immature.

"This approval represents a significant milestone for patients with recurrent or metastatic nasopharyngeal carcinoma and for the development of iza-bren," said Dr. Jonathan Cheng, Chief Medical Officer of SystImmune. "Patients who have progressed following platinum-based chemotherapy and immunotherapy face a poor prognosis with limited treatment options. The approval of iza-bren provides a new therapeutic option that has demonstrated clinically meaningful improvements in tumor response and progression-free survival compared to chemotherapy."

"Today marks a historic milestone for Biokin and SystImmune as we celebrate the first regulatory approval of iza-bren anywhere in the world," said Dr. Yi Zhu, Chairman and Chief Executive Officer of Biokin. "In fact, this is the first bispecific ADC approval of any kind globally. This approval validates our innovative EGFR×HER3 bispecific ADC design and the potential of our proprietary brengitecan-based ADC platform. Most importantly, it brings an important new treatment option to patients with recurrent or metastatic nasopharyngeal carcinoma who urgently need better therapies. We thank the patients, investigators, and healthcare professionals who made this achievement possible and look forward to advancing iza-bren for patients worldwide across multiple tumor types."

About BL-B01D1-303
BL-B01D1-303 is a phase III, randomized, open-label, multicenter study in China to evaluate the efficacy and safety of BL-B01D1 in patients with recurrent or metastatic nasopharyngeal carcinoma who have failed PD-1/PD-L1 monoclonal antibody and at least two lines chemotherapy (one line must contain platinum-based chemotherapy). For more detailed information, please visit clinical.trials.gov (NCT06118333).

About Nasopharyngeal Carcinoma (NPC)
Nasopharyngeal carcinoma (NPC) is a cancer that arises from the nasopharynx, the upper part of the throat located behind the nose. Although uncommon globally, NPC is endemic in southern China, Southeast Asia, and certain regions of North Africa. Epstein-Barr virus (EBV) infection is strongly associated with the development of NPC. Patients with recurrent or metastatic disease who have progressed after standard therapies continue to face poor outcomes, with 5-year overall survival rate generally less than 10%, representing a significant unmet medical need.

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, which 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 novel Topo1i payload is released causing cytotoxic 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
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.

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SOURCE SystImmune, Inc.