Anbenitamab Injection Combo Meets pCR End Point in HER2+ Breast Cancer

Anbenitamab injection (KN026) and albumin-bound docetaxel (HB1801) met the pre-specificized primary end point of pathological complete response (pCR) rate, which was noted as statistically and clinically significant, according to findings from the phase 3 Neo-Healer trial (NCT06747338) assessing patients with early or locally advanced HER2-positive (HER2+) breast cancer.¹

Of note, further details from the study will be presented at an upcoming international medical conference.

Previous Regulatory Actions

A new drug application was accepted in September 2025 by the National Medicinal Products Administration (NPMA) for anbenitamab injection therapy in the second line and beyond HER2+ advanced gastric cancer.² The basis of the acceptance was from results from the phase 2/3 KN026-001 trial (NCT05427383). The trial showed prolonged progression-free survival (PFS) and overall survival (OS), with no new safety signals observed.

By an independent review committee assessment, the objective response rate (ORR) was 40%, and the median PFS was 8.6 months.

Additionally, anbenitamab injection was given breakthrough therapy designation by the Center for Drug Evaluation of the NPMA in November 2023, and priority review status in August 2025.

Additionally, the FDA has granted orphan drug designation to anbenitamab injection for HER2+ or HER2-low expressing gastric cancer.

Neo-Healer Trial Design

The phase 3 study was a randomized, controlled, open-label multicenter study to assess efficacy and safety of neoadjuvant anbenitamab injection plus albumin-bound docetaxel with or without carboplatin for patients with early or locally advanced HER2+ breast cancer.³

An estimated 520 patients were randomly assigned 1:1 and stratified by disease stage, hormone receptor status, and potential use of carboplatin. Patients were to receive 6 cycles of neoadjuvant therapy consisting of anbenitamab injection plus albumin-bound docetaxel with or without carboplatin or trastuzumab (Herceptin) plus pertuzumab (Perjeta) and docetaxel with or without carboplatin.

Secondary end points included event-free survival, tpCR, bpCR, ORR, invasive disease-free survival, and frequency and severity of treatment-emergent adverse effects and serious adverse effects.

Patients were included in the trial if they could voluntarily participate and sign informed consent; were 18 years or older; had histologically confirmed primary invasive carcinoma of the breast with early or locally advanced stage; had an ECOG performance status of 0 to 1; had HER2+ status; agreed to receive surgical treatment for breast cancer and participate in research when the surgical standard is reached after neoadjuvant therapy; and had adequate organ and bone marrow function. Those who were of childbearing age or their partners must have used effective contraception.

Patients were excluded from the study if they had inflammatory or bilateral breast cancer; history of non-breast malignancies within 3 year prior to study entry, except for carcinoma in situ of the cervix or breast, and basal cell and squamous cell carcinoma of the skin; contraindications for breast cancer surgery; prior lumpectomy and/or axilla lymph node dissection biopsy prior to randomization, except for those with a diagnostic biopsy or primary breast cancer or surgery for benign breast tumors; previous systemic chemotherapy, endocrine therapy, anti-HER2 biological therapy, or local radiotherapy for breast cancer; allergens or contraindications to glucocorticoids; and congenital or acquired immune deficiency.

References

1. Phase III clinical study of anbenitamab (KN026) in combination with docetaxel (albumin-bound) (HB1801) for neoadjuvant treatment of HER2+ breast cancer meets primary endpoint. News release. CSPC Pharmaceutical Group Limited. Accessed April 1, 2026. https://tinyurl.com/3hdsfmnb
2. The new drug application for KN026 (Anbenitamab Injection) has been accepted by the National Medical Products Administration. News release. Alphamab Oncology. September 12, 2025. Accessed April 1, 2026. https://tinyurl.com/yxe6aa6y
3. A Phase III study of KN026 in combination with HB1801 ± carboplatin as neoadjuvant treatment for early or locally advanced HER2-positive breast cancer (Neo-Healer). ClinicalTrials.gov. Updated April 24, 2025. Accessed April 1, 2026. https://tinyurl.com/45e398bp