2026 ASCO Preview | Results from Phase III Study of Anbenitamab (KN026) Combined with HB1801 in Neoadjuvant Treatment for Breast Cancer Selected for LBA Oral Presentation

SUZHOU, China, April 22, 2026 /PRNewswire/ -- Alphamab Oncology (stock code: 9966.HK) today announced that the significant results from the Phase III clinical study (KN026-004) of HER2 bispecific antibody Anbenitamab Injection (KN026), 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 albumin-bound Docetaxel for Injection (HB1801) from CSPC as neoadjuvant treatment of breast cancer, have been selected for presentation at Late-Breaking Abstract (LBA) Oral Presentation Session of the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting. The study was led by Professor Zhimin Shao of Fudan University Shanghai Cancer Center as the principal investigator. This marks a major breakthrough for China-originated innovative therapies on the international academic stage.

The ASCO Annual Meeting is the largest and most prestigious annual conference in the global oncology field. LBA Oral Presentation represents the most highly anticipated segment of the meeting, showcasing clinical research findings of the greatest clinical significance and with the strongest potential to change clinical practice. The 2026 ASCO Annual Meeting will be held from May 29, 2026 to June 2, 2026 (local time) in Chicago, the United States.

Title: Anbenitamab plus albumin-bound docetaxel (nab-docetaxel) ± carboplatin (Cb) versus trastuzumab and pertuzumab plus docetaxel (THP) ± Cb as neoadjuvant therapy for HER2-positive early or locally advanced breast cancer: A randomized, open-label, multicenter, phase 3 trial
Presentation Format: Oral Presentation
Abstract Number: LBA660
Principal Investigator: Professor Zhimin Shao, Fudan University Shanghai Cancer Center
Presentation Time: May 30, 2026, 3:39-3:51 PM CDT

KN026-004 is a randomized, controlled, open-label, multicenter Phase III study designed to evaluate the efficacy and safety of anbenitamab plus HB1801 ± carboplatin versus trastuzumab plus pertuzumab and docetaxel ± carboplatin as neoadjuvant therapy for early or locally advanced HER2-positive breast cancer. The results demonstrated that compared with the current standard of care regimen (TCbHP), the KN026 combination therapy significantly improved the total pathological complete response (tpCR) in patients. These findings indicate that the HER2 bispecific antibody outperformed the dual monoclonal antibody combination of trastuzumab plus pertuzumab, providing the first head-to-head phase III evidence that confirms the "1+1>2" advantage of a HER2 bispecific antibody, with a manageable safety profile. The KN026 combination therapy has the potential to become a new standard of care for neoadjuvant treatment of early and locally advanced HER2-positive breast cancer.

About Anbenitamab (KN026)

Anbenitamab (KN026) is an anti-HER2 bispecific antibody independently developed by Alphamab Oncology 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 ADCC and CDC effects while promoting the down-regulation of HER2 receptors on the cell surface.

In September 2025, the first New Drug Application (NDA) for anbenitamab injection has been accepted by the National Medical Products Administration (NMPA) for the treatment of HER2-positive gastric cancer (GC), and currently under review. Currently, several pivotal clinical trials of KN026 for first-line HER2-positive breast cancer (BC), neoadjuvant treatment and adjuvant treatment of HER2-positive BC are being conducted.

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 Breakthrough Therapy Designation by NMPA for the treatment of patients with HER2-positive GC/GEJ who have failed first-line standard treatment.

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 an GC/GEJ in Mainland China (excluding Hong Kong, Macau and Taiwan).

About HB1801

HB1801 is one of the representative drugs independently developed by the Group's nanomedicine technology platform. Currently, multiple modified drugs developed based on this technology platform have been approved for launch, including mitoxantrone liposome, irinotecan liposome and paclitaxel (albumin-bound). Docetaxel is a paclitaxel analogue that is currently widely used in clinical practice both domestically and overseas for the monotherapy or combination therapy of multiple solid tumors such as breast cancer, non-small cell lung cancer, gastric cancer and pancreatic cancer. However, docetaxel has high hydrophobicity, and current formulations need to use polysorbate 80 (Tween-80) and ethanol as solvents, leading to many limitations in clinical application: it is easy to cause severe allergic reactions, can only be administered at low concentration and low drip rate; the product has poor compatibility and stability, requiring the use of infusion devices without polyvinyl chloride (PVC) material and making clinical use inconvenient. HB1801 encapsulates docetaxel in human serum albumin. Because it does not contain Tween-80 and ethanol, it has the following advantages compared with docetaxel injection: (1) Safety: no hormone pretreatment is required, it can be administered rapidly at high concentration, with higher safety and patient compliance; (2) Efficacy: it has significant effects in multiple preclinical tumor models, and can be administered at a larger dose clinically, further improving efficacy.

Results of multiple early clinical studies at different stages showed that HB1801 demonstrated better anti-tumor efficacy and safety than docetaxel injection, achieving the goal of reducing toxicity and increasing efficacy. Currently, HB1801 has entered the pivotal registrational Phase III clinical trial stage in indications such as breast cancer and gastric 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.

One product has 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. The NMPA has accepted the new drug application for KN026 (Anbenitamab Injection), a HER2 bispecific antibody, for second-line or later HER2-positive gastric cancer, and currently under review. Five bispecific ADC candidates have entered clinical stages, and next-generation ADC pipelines—such as dual-payload ADCs—are advancing rapidly. The Company has established strategic partnerships with organizations including CSPC, ArriVent, and Glenmark, 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.

SOURCE Alphamab Oncology