Inetetamab Combined With Pyrotinib and Vinorelbine as First-line to Third-line Treatment for HER2-positive Metastatic Breast Cancer

Study Overview
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Brief Summary
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This is a real world study to evaluate the efficacy and safety of inetetamb combined with pyrotinib and vinorelbine as first-line to third-line treatment after trastuzumab progression in HER2-positive metastatic breast cancer.

Detailed Description
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HER2-positive breast cancers account for 15%-20% of all breast cancers. Despite trastuzumab has significantly improved the survival of patients with HER2-positivie metastatic breast cancer as the first-line standard treatment, the selection of drugs after trastuzumab treatment failure remains difficulty and challenge. Inetetamab, a new antibody to optimize the ADCC effect, has shown great effectiveness in treating HER2-positive metastatic breast cancer, but therapies subsequent to trastuzumab progression are still controversial. Pyrotinib, another second-line HER2 targeted drug, is a typical representative of TKI drugs, which not only has a strong HER2 antagonistic effect but also can synergize with monoclonal antibodies to amplify the ADCC effect. Here, investigators studied the efficacy and safety of inetetamb combined with pyrotinib and vinorelbine as first-line to third-line treatment after trastuzumab progression, so as to provide new ideas for the treatment of patients with HER2-positive metastatic breast cancer.

Official Title
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Real World Study of Inetetamab Combined With Pyrotinib and Vinorelbine as First-line to Third-line Treatment for Trastuzumab Resistant HER2-positive Metastatic Breast Cancer: a Multicenter, Retrospective Study

Conditions
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Breast Neoplasms

Intervention / Treatment
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* Drug: Inetetamab
* Drug: Pyrotinib
* Drug: Vinorelbine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female and 18-80 years old; The patient was diagnosed as HER2-positive breast cancer by histopathology (HER2 positive (IHC +++ or IHC++ but FISH/CISH+ )); All patients have previously received ≤ 2 lines chemotherapy for metastatic breast cancer; Patients received inetetamab combined with pyrotinib and vinorelbine after trastuzumab failure; According to RECIST 1.1, patients with at least one target lesion or simple bone metastasis can be evaluated; ECOG score of physical status was less than 2, and the expected survival time was not less than 3 months; Complete and traceable medical data. Exclusion Criteria: Incomplete medical data; The investigator believes that the patient is not suitable to enter this study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Observational Group<br>Patients receive initetamab combined with pyrotinib and vinorelbine after trastuzumab progression. | Drug: Inetetamab<br>* 8mg/kg for the first dose, 6mg/kg for the following doses, every 3 weeks for one cycle.<br>Drug: Pyrotinib<br>* 400mg, oral, every day.<br>Drug: Vinorelbine<br>* 25 mg/m2, D1, D8, every 3 weeks for one cycle.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Progression Free Survival (PFS) | Progression-free survival estimated using Kaplan-Meier methods is defined as the time from the date of informed consent to the earlier of death or disease progression. Patients alive without disease progression are censored at the date of last disease evaluation. Progressive disease (PD) based on RECIST 1.1 is at least a 20% increase in the sum of longest diameter (LD) of target lesions taking as reference the smallest sum LD recorded since the treatment started or the appearance of one or more new lesions. Equivocal progression of non-target lesions also qualifies as PD. | 2 years | 
| Objective Response Rate (ORR) | The overall response rate is defined as the percentage of patients with a best overall response of CR or PR relative to the appropriate analysis set | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Number of Participants Who Experienced Adverse Events (AE) | Safety will be assessed by standard clinical and laboratory tests (haematology, serum chemistry). AE grade were defined by the NCI CTCAE (National Cancer Institute Common Terminology Criteria for Adverse Events). | 2 years |