Suzhou, China, August 5, 2026 - Alphamab Oncology (stock code: 9966.HK) today announced that the New Drug Application (NDA) for Anbenitamab (brand name: 恩尼妥®, KN026), a HER2 bispecific antibody independently developed by the Company, and co-developed with JMT-Bio Technology Co., Ltd., a wholly-owned subsidiary of CSPC Pharmaceutical Group Co., Ltd. (stock code: 1093.HK), in combination with CSPC’s Docetaxel for Injection (Albumin-bound) (HB1801), for the neoadjuvant treatment of early or locally advanced HER2-positive breast cancer has been accepted by the National Medical Products Administration (NMPA) and granted priority review designation.
Anbenitamab is the first domestically developed HER2 bispecific antibody approved for marketing in China. This new indication marks the second NDA submission for Anbenitamab following its approved indication for locally advanced or metastatic HER2-positive gastric cancer/gastroesophageal junction cancer (GC/GEJ) in adults, and is expected to become a new standard of care for neoadjuvant therapy in HER2-positive early or locally advanced breast cancer.
Pivotal Phase III Study Demonstrates Superior Efficacy, World’s First Head-to-Head Superiority Over Trastuzumab Plus Pertuzumab
The NDA submission is based on the pivotal Phase III clinical trial (KN026-004/Neo-Healer), the results of which were presented at the 2026 ASCO Annual Meeting in June. The study demonstrated that Anbenitamab combined with HB1801±carboplatin as neoadjuvant treatment for HER2-positive early or locally advanced breast cancer achieved a total pathological complete response (tpCR) rate of 62.4% (95% CI: 56.20–68.23) , with a one-sided P value of 0.0036, representing a statistically significant improvement in tpCR versus the current standard of care (trastuzumab plus pertuzumab and docetaxel±carboplatin), with a manageable overall safety profile. Anbenitamab is the first antibody drug worldwide to demonstrate significantly superior efficacy over trastuzumab plus pertuzumab in a head-to-head Phase III trial, and the first bispecific antibody with Phase III clinical evidence directly validating superior efficacy over the combination of two monospecific antibodies targeting the same tumor antigen.
Addressing Unmet Early-Stage Needs to Improve Long-Term Prognosis Benefits
In China, approximately 75% of breast cancer patients are initially diagnosed at early or locally advanced stages. Neoadjuvant therapy is the recommended standard of care for HER2-positive early or locally advanced breast cancer, and achieving tpCR through neoadjuvant treatment is a key goal and effective means to improve long-term prognosis, carrying substantial clinical value. The current standard regimen of trastuzumab plus pertuzumab combined with chemotherapy has been used for many years, yet a considerable proportion of patients still fail to achieve pathological complete response, representing a significant unmet medical need. The combination of Anbenitamab with chemotherapy (KN026+HB1801±carboplatin) significantly improves tpCR, with the potential to further reduce postoperative recurrence risk and deliver better long-term outcomes for more patients with early-stage HER2-positive breast cancer. Furthermore, this regimen employs a single-stage, continuous 6-cycle treatment design without the need for drug switching or segmented treatment. Compared with the two-stage sequential 8-cycle neoadjuvant regimen (T-DXd followed by THP), patients can undergo radical surgery approximately 6 weeks earlier, offering advantages in treatment efficiency and clinical compliance.
Multi-Dimensional Advantages Build Full Treatment-Cycle Coverage for Breast Cancer
Anbenitamab is a HER2 bispecific antibody independently developed by Alphamab Oncology based on its proprietary CRIB (Charge Repulsion Improved Bispecific) platform. It simultaneously binds two non-overlapping epitopes of the HER2 receptor (domain IV and domain II) with high affinity and engages multiple HER2 proteins on tumor cell membranes, enabling comprehensive blockade of downstream signaling pathways and representing a landmark innovation in the HER2-targeted space. In clinical practice, Anbenitamab requires no reconstitution and can be directly prepared for administration, simplifying the infusion process; HB1801 can be administered as a high-concentration rapid infusion without mandatory corticosteroid premedication, offering greater convenience compared with conventional docetaxel.
Leveraging its differentiated product profile and robust clinical data, Anbenitamab in combination with HB1801 is steadily advancing the full treatment-cycle clinical development layout for breast cancer. Beyond the currently neoadjuvant indication under review, the Phase III study in first-line HER2-positive breast cancer has successfully met its primary endpoint of progression-free survival (PFS), and the adjuvant Phase III trial in patients at high risk of postoperative recurrence is ongoing. Together, these studies cover the entire treatment pathway from preoperative neoadjuvant, postoperative adjuvant, to advanced systemic therapy.
About 恩尼妥® (Anbenitamab Injection)
恩尼妥® (Anbenitamab injection, KN026) is an anti-HER2 bispecific antibody independently developed by the Company using the proprietary Fc-based heterodimer bispecific platform technology called CRIB (Charge Repulsion Induced Bispecific). Anbenitamab can simultaneously bind two non-overlapping epitopes of HER2, resulting in HER2 signal blockade. Through antibody-induced receptor clustering, it enhances antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) effects while promoting the down-regulation of HER2 receptors on the cell surface.
In May 2026, 恩尼妥® obtained approval for marketing from the National Medical Products Administration of China (NMPA) through the priority review and approval pathway for combination with chemotherapy for the treatment of adult patients with locally advanced or metastatic HER2 positive gastric cancer/gastroesophageal junction cancer (GC/GEJ) who have previously received at least one trastuzumab-containing regimen. Two Phase III clinical studies of neoadjuvant treatment for HER2-positive breast cancer (BC) and first-line treatment of HER2-positive BC have reached the primary endpoints, and New Drug Application (NDA) for neoadjuvant treatment of BC has been accepted by NMPA. Currently, multiple registrational clinical trials of Anbenitamab for indications such as adjuvant treatment of HER2-positive BC and first-line treatment of HER2-positive GC/GEJ are ongoing.
Anbenitamab has been granted Orphan Drug Designation by the U.S. Food and Drug Administration (FDA) for the treatment of HER2-positive or low expressing GC; it has been granted two Breakthrough Therapy Designations by NMPA for the treatment of patients with HER2-positive GC/GEJ who have failed first-line standard treatment, and first-line treatment of patients with unresectable or metastatic HER2-positive BC.
In August 2021, the Company entered an agreement with JMT-Bio Technology Co., Ltd. (JMT-Bio), a wholly-owned subsidiary of CSPC Pharmaceutical Group Co., Ltd. (CSPC) (stock code: 1093.HK), for the development and commercialization of KN026 in Mainland China. JMT-Bio was granted exclusive license rights of KN026 for the development and commercialization in the indications of BC and GC/GEJ in Mainland China (excluding Hong Kong, Macau and Taiwan).
About Docetaxel (Albumin-bounded) HB1801
Docetaxel (Albumin-Bound) for Injection (HB1801) is one of the flagship drugs independently developed by CSPC Group on its proprietary nanomedicine technology platform. With docetaxel encapsulated in human serum albumin and free of Tween-80 and ethanol, HB1801 has the following advantages over conventional docetaxel injection: (1) Safety: No steroid premedication is needed. It can be rapidly administered at high concentrations, featuring superior safety and better patient compliance; (2) Efficacy: It has exhibited remarkable efficacy in multiple preclinical tumor models and several early-stage clinical studies. Higher doses can be applied clinically to further improve therapeutic outcomes. HB1801 has currently entered pivotal phase III registrational clinical trials for indications including breast cancer and gastric cancer. HB1801 has been granted Breakthrough Therapy Designation by NMPA for first-line treatment of patients with unresectable or metastatic HER2-positive breast cancer.
About Alphamab Oncology
Alphamab Oncology (Stock Code: 9966.HK) is an innovative biopharmaceutical company focused on oncology. Leveraging proprietary platforms-including single-domain antibodies, bispecific antibodies, glycan-specific conjugation, linker-payloads, dual-payload ADCs, and high-concentration subcutaneous formulations, the Company has built a differentiated and globally competitive pipeline, covering cutting-edge candidates in ADCs, bispecific antibodies, and single-domain antibodies.
Two products have received market approval: Envafolimab (KN035, brand name: 恩维达®), the world's first subcutaneously injected PD-(L)1 inhibitor, offering greater convenience and accessibility in cancer treatment; and Anbenitamab (KN026, brand name: 恩尼妥®), the first domestically developed HER2 bispecific antibody approved for marketing in China, redefining the standard of treatment for second‑line HER2‑positive gastric cancer. Six bispecific ADC and dual-payload ADC candidates are currently in clinical development, and next-generation ADC pipelines are advancing rapidly. The Company has established strategic partnerships with organizations including CSPC, ArriVent, Glenmark, and Pathos, covering both product development and technology platforms.
Our overarching mission is to make cancer manageable and curable by addressing unmet clinical needs in oncology. Alphamab Oncology is continuously dedicated to the development of effective, safe, and globally competitive anti-tumor drugs, enabling patients to achieve long-term, high-quality survival and delivering China-innovated cancer therapies to benefit patients worldwide.
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