A Study of A166 Versus Trastuzumab Emtansine (T-DM1) in Patients With HER2-Positive Unresectable or Metastatic Breast Cancer Previously Treated With Trastuzumab and Taxane Therapy

Kelun Pharmaceutical

Status and phase: Active, not recruiting; Phase 3

Conditions: HER2-positive Breast Cancer

Treatments: Drug: A166; Drug: T-DM1

Study type: Interventional

Funder types: Industry

Identifiers

NCT06968585

KL166-III-06

Details and patient eligibility

About

Evaluation of the efficacy of A166 versus trastuzumab emtansine (T-DM1) in Patients with HER2-Positive unresectable or metastatic breast cancer previously treated with trastuzumab and taxane therapy

Full description

This study will evaluate the efficacy of A166 versus trastuzumab emtansine (T-DM1) in patients with HER2-positive unresectable or metastatic breast cancer previously treated with trastuzumab and taxane therapy

To further evaluate the efficacy of A166 versus T-DM1 in patients with HER2-positive unresectable or metastatic breast cancer, based on effectiveness endpoints including:

Overall survival (OS)

Progression-free survival (PFS) as assessed by investigators

Objective response rate (ORR), disease control rate (DCR), duration of response (DOR), and clinical benefit rate (CBR) assessed by both blinded independent central review (BICR) and investigators.

To assess the safety profile of A166 for injection in patients with HER2-positive unresectable or metastatic breast cancer.

To evaluate the immunogenicity of A166 for injection in patients with HER2-positive unresectable or metastatic breast cancer.

To characterize the pharmacokinetic (PK) profile of A166 for injection in patients with HER2-positive unresectable or metastatic breast cancer.

Enrollment: 365 patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Male or female patient ≥ 18 years and ≤ 75 years when signing the informed consent form.
2. Breast cancer patients by histopathology and/or cytology documented.
3. Disease progression after receiving a trastuzumab-based regimen (or a commercially available trastuzumab biosimilar or inetetamab) in the advanced or metastatic setting, or disease progression/recurrence within 12 months during or after (neo)adjuvant therapy (with a trastuzumab-based regimen or commercially available trastuzumab biosimilar).
4. Have previously received taxanes.
5. Patients must have experienced disease progression or intolerance during or after the most recent treatment prior to randomization.
6. At least one measurable lesion according to RECIST 1.1 criteria

Exclusion criteria

1. Previous treatment with A166 or any HER2-targeted antibody-drug conjugate (ADC) with a microtubule inhibitor payload.
2. Known history of severe hypersensitivity to other monoclonal antibodies, or allergy to A166 , T-DM1 (trastuzumab emtansine) or their components.
3. Permanent discontinuation of trastuzumab or its biosimilars due to any toxicity in prior treatments.
4. Presence of severe corneal epithelial disease at baseline; or inability to perform daily activities without contact lenses.
5. Presence of spinal cord compression or clinically active central nervous system (CNS) metastases.
6. Other conditions considered by the investigator to make the patient unsuitable for participation in the study

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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365 participants in 2 patient groups

A166

Experimental group

Description:

A166 is administered intravenously at a dose of 4.8 mg/kg every 21 (±3) days (q3w).

Treatment:

Drug: A166

T-DM1

Active Comparator group

Description:

T-DM1 is administered intravenously at a dose of 3.6 mg/kg every 21 (±3) days (q3w).

Treatment:

Drug: T-DM1