Trastuzumab Rezetecan Followed by Pyrotinib, and Trastuzumab Combined With Capecitabine as First-line Treatment for Advanced HER2-positive Breast Cancer

NCT07766772 | Not Yet Recruiting Phase 2

• 1 other identifier: OBU-BC-II-345
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

This study is a single-arm, exploratory clinical trial, aiming to include patients with HER2-positive advanced breast cancer. It intends to explore the efficacy and safety of trastuzumab combined with pyrotinib, capecitabine ± endocrine therapy as a first-line maintenance treatment for HER2+ advanced breast cancer after induction therapy with rucaparib trastuzumab. After the subjects meet the screening criteria and are enrolled, they receive induction therapy with rucaparib trastuzumab. Among them, patients without disease progression enter the maintenance treatment period and receive trastuzumab combined with pyrotinib, capecitabine ± endocrine therapy (±OFS) for treatment. Until disease progression, or toxicity becomes intolerable, or withdrawal of informed consent, or the investigator determines that the medication must be discontinued. During the study period, imaging evaluations are conducted according to the RECIST 1.1 standard, and the center assessment results are the final results. During the study period, the efficacy indicators such as PFS, ORR, DOR, CBR, and safety indicators of the subjects are evaluated according to the established trial standards, and statistical descriptions are conducted.

Conditions

HER2 + Breast Cancer; Advanced Breast Cancer

Outcome Measures

Primary Outcomes (1)

• progression free survival(PFS)

  The duration from the start of the induction period treatment to the observation of disease progression or the occurrence of death due to any cause.

  From enrollment to 3 years

Secondary Outcomes (5)

• objective remission rate(ORR)

  From enrollment to 3 years

• duration of response(DoR)

  From enrollment to 3 years

• Clinical Benefit Rate(CBR)

  From enrollment to 3 years

• Number of participants with treatment-related adverse events as assessed by CTCAE v5.0

  From the time of enrollment until 30 days after the completion of the study

• Overall Survival(OS)

  From enrollment to 3 years

Study Arms (1)

Trastuzumab Rezetecan followed by Pyrotinib + Trastuzumab + Capecitabine ± endocrine therapy Group

EXPERIMENTAL

After receiving Trastuzumab Rezetecan for Injection induction therapy, a combined treatment regimen of pyrotinib, trastuzumab, and capecitabine ± endocrine therapy was used for maintenance treatment.

Drug: Trastuzumab Rezetecan; Drug: Pyrotinib; Drug: trastuzumab; Drug: Capecitabine; Drug: endocrinotherapy（doctor's choice）

Interventions

Trastuzumab Rezetecan DRUG

Administer intravenously at a dose of 4.8 mg/kg every 3 weeks (Q3W), with each 3-week period constituting one treatment cycle.

Trastuzumab Rezetecan followed by Pyrotinib + Trastuzumab + Capecitabine ± endocrine therapy Group

Pyrotinib DRUG

Take orally once daily, 400 mg each time.

Trastuzumab Rezetecan followed by Pyrotinib + Trastuzumab + Capecitabine ± endocrine therapy Group

trastuzumab DRUG

Intravenous infusion: Initial dose 8mg/kg, subsequent dose 6mg/kg, 3 weeks as one cycle; Subcutaneous injection: Fixed dose 600mg (not based on the subject's weight), administration completed within 2-5 minutes, 3 weeks as one cycle.

Trastuzumab Rezetecan followed by Pyrotinib + Trastuzumab + Capecitabine ± endocrine therapy Group

Capecitabine DRUG

Oral administration, 3 times a day, 500 mg each time

Trastuzumab Rezetecan followed by Pyrotinib + Trastuzumab + Capecitabine ± endocrine therapy Group

endocrinotherapy（doctor's choice） DRUG

Administer the medication according to the recommended regimen specified in the doctor's instructions for endocrine therapy. For patients with HR-positive disease, they can choose to use

Trastuzumab Rezetecan followed by Pyrotinib + Trastuzumab + Capecitabine ± endocrine therapy Group

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Female participants aged 18 to 75 years (inclusive)
• Breast cancer must meet the following criteria:
• HER2-positive breast cancer confirmed by histology or cytology (HER2 positivity defined as IHC 3+ or ISH+ in primary or metastatic lesions); locally advanced or metastatic breast cancer not amenable to curative surgery (participants eligible for curative treatment are excluded);
• Clear HR status (HR-positive defined as ER and/or PR positive in primary or metastatic lesions, with ≥1% of tumor cells showing ER and/or PR staining);
• No prior systemic anticancer therapy during the recurrent/metastatic phase (except ≤1 line of endocrine therapy allowed);
• For patients receiving (neo)adjuvant therapy, the interval between completion of systemic therapy (excluding endocrine therapy) and detection of recurrence/metastasis must be \>12 months.
• ECOG performance status of 0 or 1.
• Organ function deemed adequate for study drug administration by the investigator.
• Pregnancy and contraception:
• Sexually active female participants (WOCBP) must agree to use highly effective contraception from the screening visit through 7 months after the last dose of investigational product, and must agree not to breastfeed.
• Participants must voluntarily enroll in the study, sign informed consent, demonstrate good compliance, and be willing to cooperate with all study visits and procedures.

You may not qualify if:

• Patients with active central nervous system metastases who have not undergone surgery or radiation therapy, except those whose condition has been stable for at least one month after treatment and who have discontinued corticosteroids for more than 2 weeks.
• A history of other malignancies within the past 5 years, excluding cured cases of cutaneous basal cell carcinoma, cervical carcinoma in situ, and papillary thyroid carcinoma.
• Presence of third-space fluid accumulation (e.g., large volume ascites, pleural effusion, pericardial effusion) that cannot be controlled by drainage or other means.
• Patients who have received surgery (defined as major cancer-related surgery), radiation therapy, chemotherapy, immunotherapy, molecularly targeted therapy, biological therapy, or participated in other drug clinical trials within 4 weeks prior to the first dose of study medication.
• Prior exposure to antibody-drug conjugates containing irinotecan derivatives as topoisomerase I inhibitors, such as T-DXd (DS-8201a).
• Administration of live or live-attenuated vaccines within 4 weeks prior to the first dose of study medication.
• History of immunodeficiency, including positive HIV test results, other acquired or congenital immunodeficiency disorders, or a history of organ transplantation.
• Clinically significant cardiovascular disease, such as severe/unstable angina, symptomatic congestive heart failure (NYHA ≥ II), clinically significant supraventricular or ventricular arrhythmias requiring treatment or intervention, or myocardial infarction occurring within 6 months prior to the first dose.
• Known or suspected interstitial lung disease; presence of moderate to severe pulmonary conditions within 3 months prior to the first dose that could significantly impair respiratory function or interfere with assessment or management of drug-related pulmonary toxicity, including but not limited to idiopathic pulmonary fibrosis, organizing pneumonia/obstructive bronchiolitis, pulmonary embolism, severe asthma, severe chronic obstructive pulmonary disease (COPD), obstructive/restrictive lung diseases, or cancerous lymphangitis; any autoimmune, connective tissue, or inflammatory disease involving the lungs, such as rheumatoid arthritis, Sjögren's syndrome, sarcoidosis, or prior history of pneumonectomy. Patients with a prior history of interstitial lung disease grade ≥3 are excluded from this study.
• Known hereditary or acquired bleeding tendency (e.g., hemophilia, coagulation disorders).
• Active hepatitis B (HBsAg positive and HBV DNA ≥500 IU/mL), hepatitis C (HCV antibody positive and HCV RNA above the upper limit of normal), cirrhosis; or severe infections requiring intravenous antibiotics, antivirals, or antifungal agents for control.
• According to the National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0 (NCI-CTCAE v5.0), patients whose toxicity from prior anticancer treatments has not recovered to ≤Grade 1 (except alopecia; certain tolerable chronic Grade 2 toxicities may be allowed at the investigator's discretion, such as Grade 2 peripheral neuropathy).
• Known hypersensitivity to any of the investigational drugs, their excipients, or other monoclonal antibodies.
• Other serious physical or psychiatric conditions or laboratory abnormalities that may increase the risk of participation in the study or interfere with study outcomes, or patients deemed unsuitable for participation by the investigator.

Sponsors & Collaborators

• Fujian Cancer Hospital: lead

Study Sites (1)

Fujian Cancer Hosptial

Fuzhou, Fujian, 350004, China

Location

MeSH Terms

Conditions

Breast Neoplasms

Interventions

pyrotinib; Trastuzumab; Capecitabine

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases

Intervention Hierarchy (Ancestors)

Antibodies, Monoclonal, Humanized; Antibodies, Monoclonal; Antibodies; Immunoglobulins; Immunoproteins; Blood Proteins; Proteins; Amino Acids, Peptides, and Proteins; Serum Globulins; Globulins; Deoxycytidine; Cytidine; Pyrimidine Nucleosides; Pyrimidines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Fluorouracil; Uracil; Pyrimidinones; Deoxyribonucleosides; Nucleosides; Nucleic Acids, Nucleotides, and Nucleosides

Central Study Contacts

Fan Wu, doctor

CONTACT

13859082118; alienglass@fjmu.edu.cn

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: chief physicians

Study Record Dates

• First Submitted: July 30, 2026
• First Posted: August 14, 2026
• Study Start: September 30, 2026
• Primary Completion (Estimated): December 31, 2031
• Study Completion (Estimated): December 31, 2031
• Last Updated: August 14, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)