A Phase II Study of HLX22 in Combination With Trastuzumab Deruxtecan in HER2-low, Hormone Receptor Positive Locally Advanced or Metastatic Breast Cancer Patients

A Phase II Study of HLX22 (Recombinant Humanized Anti-HER2 Monoclonal Antibody Injection) in Combination With Trastuzumab Deruxtecan (T-DXd) in HER2-low, Hormone Receptor Positive Locally Advanced or Metastatic Breast Cancer Patients With Intolerable Adverse Reaction or Disease Progression on Standard of Care

This is a Phase II Study of HLX22 in Combination with Trastuzumab Deruxtecan (T-DXd) in HER2-low, Hormone Receptor Positive Locally Advanced or Metastatic Breast Cancer Patients with Disease Progression or Intolerable Adverse Reaction on Standard of Care. Eligible subjects will be treated with the study drug until the loss of clinical benefit, death, intolerable toxicity, withdrawal of informed consent, or other reasons specified by the protocol (whichever occurs first).

Study Overview

• Status: Recruiting
• Conditions: HER2-low Hormone Receptor Positive Breast Cancer
• Intervention / Treatment: Drug: HLX22; Drug: Trastuzumab Deruxtecan

Detailed Description

experimental group: HLX22(15 mg/kg) + Trastuzumab Deruxtecan( 5.4 mg/kg), once every 3 weeks (Q3W).

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Yun Li; Phone Number: +86-15800864157; Email: Shirley_Li@henlius.com

Study Locations

• China
  • Shanghai
    • Shanghai, Shanghai, China, 200000
      • Recruiting
      • Fudan University Shanghai Cancer Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Male/female who are at least 18 years of age on the day of signing the informed consent.
2. With histologically confirmed diagnosis of HER2-low, Hormone Receptor Positive Locally Advanced or Metastatic Breast Cancer.
3. HER2-low defined as IHC 2+/ISH- or IHC 1+ (ISH- or untested) as assessed by a central laboratory on metastatic tumor and was never previously HER2-positive，and was documented HR+ disease in the metastatic setting
4. Had measurable disease according to the RECIST v1.1, the target lesion must not be a bone metastatic lesion only.
5. ECOG PS: 0-1.
6. Expected survival ≥ 6 months.
7. Had adequate organ function

Exclusion Criteria:

1. Patients with other malignant tumors within 3 years before the randomization
2. Previous treatment with any HER2-target therapy
3. Uncontrolled or significant cardiovascular disease or infection
4. Lung-specific intercurrent clinically significant illnesses
5. Prior documented interstitial lung disease (ILD)/ pneumonitis that required steroids, current ILD/ pneumonitis, or suspected ILD/ pneumonitis
6. Patients with spinal cord compression or clinically active central nervous system metastases

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental group; HLX22(15 mg/kg) + Trastuzumab Deruxtecan( 5.4 mg/kg), Q3W	Drug: HLX22; HLX22 15mg/kg Q3W; Drug: Trastuzumab Deruxtecan; Trastuzumab Deruxtecan 5.4mg/kg Q3W

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression-Free Survival (PFS)	Progression-Free Survival (PFS) assessed by IRRC (Independent Radiology Review Committee) per RECIST 1.1 . PFS is defined as the time from randomization to the first documented disease progression per RECIST 1.1 or death due to any cause, whichever occurs first.	Up to 5 years
Objective response rate (ORR)	Objective Response Rate (ORR) assessed by IRRC per RECIST v1.1. ORR is defined as the percentage of participants who have a Complete Response ([CR], disappearance of all evidence of disease) or Partial Response ([PR], regression of measurable disease and no new sites) per RECIST 1.1	Up to 2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
PFS	PFS assessed by investigator per RECIST 1.1 . PFS is defined as the time from randomization to the first documented disease progression per RECIST 1.1 or death due to any cause, whichever occurs first.	Up to 5 years
ORR	ORR assessed by investigator per RECIST v1.1. ORR is defined as the percentage of participants who have a Complete Response ([CR], disappearance of all evidence of disease) or Partial Response ([PR], regression of measurable disease and no new sites) per RECIST 1.1	Up to 2 years
Aderse events (AE)	AE is any untoward medical occurrence in a participant that is temporally associated with the use of study treatment, whether or not considered related to the study treatment. AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study treatment.	Up to 5 years

Collaborators and Investigators

• Sponsor: Shanghai Henlius Biotech

Study record dates

Study Major Dates

• Study Start (Actual): April 16, 2025
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): December 1, 2029

Study Registration Dates

• First Submitted: February 12, 2025
• First Submitted That Met QC Criteria: February 12, 2025
• First Posted (Actual): February 18, 2025

Study Record Updates

• Last Update Posted (Actual): June 15, 2025
• Last Update Submitted That Met QC Criteria: June 12, 2025
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Breast Neoplasms; Antineoplastic Agents, Immunological; Antineoplastic Agents; Immunologic Factors; Physiological Effects of Drugs; Immunoconjugates; Trastuzumab; Trastuzumab deruxtecan
• Other Study ID Numbers: HLX22-BC201

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No