SHANGHAI, China – FEBUARY 27, 2026 – Shanghai Henlius Biotech, Inc. (2696.HK) announced that the first patient has been dosed in China in a Phase 2/3 clinical trial (HLX87-BC001) evaluating its novel-epitope anti-HER2 mAb HLX22 in combination with the innovative anti-HER2 antibody–drug conjugate (ADC) HLX87 for the first-line treatment of HER2-positive breast cancer. This milestone marks a further expansion of HLX22’s clinical development in breast cancer and underscores its potential to benefit a broader range of patients in the future.
Over the past two decades, HER2-targeted therapies have significantly improved patient outcomes.1 However, patients with HER2-positive metastatic breast cancer (mBC) eventually develop resistance, leading to disease progression. While HER2-targeted therapy in combination with chemotherapy remains the current first-line standard of care, there is a clear unmet need to further improve the overall safety profile.2,3 The clinical demand for more effective, safer, and chemotherapy-free HER2 treatment strategies is therefore increasingly urgent. HLX22 is a novel-epitope monoclonal antibody targeting HER2 that binds to subdomain IV of the HER2 extracellular region at a distinct epitope from trastuzumab. This allows HLX22 to synergistically bind with trastuzumab at non-overlapping epitopes, enhancing HER2 internalization and degradation. Animal studies of HLX22 plus trastuzumab deruxtecan (T-DXd) and data from similar clinical combinations further suggest that combining a HER2 monoclonal antibody with a HER2 ADC may yield synergistic antitumour effects with manageable toxicity.
Building on this background, Henlius is further exploring combination regimens of HLX22 with HER2 ADCs in breast cancer, with the aim of providing patients with new treatment options that offer enhanced synergistic activity and improved toxicity manageability. Henlius initiated a Phase 2 clinical trial in 2025 evaluating HLX22 in combination with standard of care or T-DXd for patients with HER2-low, HR-positive locally advanced or metastatic breast cancer (HLX22-BC201), and the patient enrolment in China has been completed.
Henlius has built a comprehensive pipeline covering the full continuum of breast cancer care through internal innovation and strategic collaborations. Its core product, HANQUYOU (trastuzumab, trade name: HERCESSI™ in the U.S., Zercepac® in Europe), has been approved in more than 50 countries and regions worldwide. HANNAIJIA (Neratinib Maleate) strengthens post-surgical risk reduction when used sequentially after HANQUYOU. POHERDY® (pertuzumab), the first—and only—FDA-approved PERJETA® biosimilar in the U.S., is currently under review in China, the EU and Canada, and may be used in combination with HANQUYOU for dual HER2 blockade. Henlius’ innovative CDK4/6 inhibitor FUTUONING (fovinaciclib citrate) has been approved in China for first- and second-line treatment of HR+/HER2- advanced breast cancer. Meanwhile, Henlius is accelerating development of multiple high-potential innovative assets, including novel-epitope HER2 antibody HLX22, endocrine therapy candidate lasofoxifene HLX78, KAT6A/B inhibitor HLX97, LIV-1-targeting ADC HLX41, HER2×HER2 biparatopic ADC HLX49, and HER2 ADC HLX87. The company aims to strengthen its synergistic pipeline and build an end-to-end therapeutic ecosystem covering the entire disease course, bringing comprehensive solutions to breast cancer patients worldwide.
About HLX22
HLX22 is a novel-epitope monoclonal antibody targeting HER2. It binds to subdomain IV of the HER2 extracellular region at an epitope distinct from that of trastuzumab, enabling simultaneous binding of HLX22 and trastuzumab to the HER2 receptor. This dual, non-overlapping epitope engagement effectively promotes the internalization and degradation of HER2 dimers (including HER2 homodimers and HER2/EGFR heterodimers), increasing HER2 internalization efficiency by 40%–80% and thereby achieving a more potent HER2 receptor blockade. Updated results from the Phase 2 clinical trial of HLX22 in combination with HANQUYOU (trastuzumab, trade name: HERCESSI™ in the U.S., Zercepac® in Europe) for HER2-positive gastric cancer (HLX22-GC-201) were presented at the American Society of Clinical Oncology (ASCO) 2025 Annual Meeting. The data showed that, after long-term follow-up (median follow-up exceeding two years), HLX22 continued to deliver durable clinical benefits in HER2-positive gastric cancer, significantly outperforming historical benchmarks.4 Based on the positive results of the Phase 2 trial, HLX22-GC-301 is a randomized, head-to-head, international multicentre Phase 3 trial evaluating the efficacy and safety of HLX22 plus trastuzumab and chemotherapy as first-line treatment with the current standard first-line regimen (trastuzumab plus chemotherapy ± pembrolizumab) for patients with HER2-positive metastatic gastric cancer or gastroesophageal junction cancer. The trial includes patients regardless of PD-L1 expression status and aims to address the limitations of current first-line treatment options for HER2-positive metastatic gastric and gastroesophageal junction cancer. In 2025, HLX22 was granted Orphan Drug Designation (ODD) by both the U.S. Food and Drug Administration (FDA) and the European Commission (EC) for the treatment of gastric cancer. This milestone marks HLX22 as the world’s first anti-HER2 targeted therapy for gastric cancer to receive Orphan Drug Designation in both the United States and the European Union, highlighting its significant therapeutic potential in this disease area. HLX22-GC-301 has completed the dosing of the first patient across multiple countries and regions, including China, the United States, Japan, Australia, and Argentina. Beyond gastric cancer, Henlius also initiated a Phase 2 clinical trial in 2025 evaluating HLX22 in combination with standard of care or T-DXd for patients with HER2-low, HR-positive locally advanced or metastatic breast cancer (HLX22-BC201), and the patient enrolment in China has been completed.
About HLX87-BC001
The trial is an open-label, randomized, multicentre Phase 2/3 clinical trial designed to evaluate HLX22 in combination with HLX87 as first-line treatment for patients with HER2-positive recurrent or metastatic breast cancer. The trial consists of two stages.
The first stage is an open-label, multicentre, randomized, parallel-controlled Phase 2 trial. Eligible patients will be randomized in a 2:2:1:1 ratio to receive one of the following treatment regimens: HLX22 in combination with HLX87; pertuzumab in combination with HLX87; pertuzumab in combination with T-Dxd; or pertuzumab in combination with trastuzumab plus docetaxel. The primary objective of the first stage is to evaluate the clinical efficacy of HLX22 in combination with HLX87, as assessed by objective response rate (ORR) and progression-free survival (PFS) determined by a blinded independent central review (BICR). The second stage is an open-label, multicentre, randomized, parallel-controlled Phase 3 study. Eligible patients will be randomized in a 1:1 ratio to receive either HLX22 in combination with HLX87 or pertuzumab in combination with trastuzumab plus docetaxel. The primary objective of the second stage is to evaluate clinical efficacy based on PFS assessed by BICR. Secondary objectives include the assessment of the safety, tolerability, pharmacokinetic (PK) profile, and immunogenicity of HLX22 in combination with HLX87. Exploratory objectives include the identification of potential predictive or resistance biomarkers.
References
1. Swain SM, Baselga J, Kim SB, Ro J, Semiglazov V, Campone M, et al. Pertuzumab, trastuzumab, and docetaxel in HER2-positive metastatic breast cancer. N Engl J Med 2015;372(8):724-34.
2. Loibl S, Gianni L. HER2-positive breast cancer. Lancet 2017;389(10087):2415-29.
3. Li H, Fu W, Gao X, Xu Q, Wu H, Tan W. Risk of severe diarrhea with dual anti-HER2 therapies: a meta-analysis. Tumour Biol 2014;35(5):4077-85.
4. Jin Li et al. HLX22 plus trastuzumab and XELOX for first-line treatment of HER2-positive locally advanced or metastatic gastric/gastroesophageal junction cancer (G/GEJC): Updated results with additional patients.. JCO 43, 440-440(2025). DOI:10.1200/JCO.2025.43.4_suppl.440