Treatment With Pyrotinib-Based Therapy in Lapatinib Resistant HER2-Positive Metastatic Breast Cancer

Study Overview
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Brief Summary
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This is a multicenter, observational, single-arm real world study to evaluate the efficacy and safety of pyrotinib after lapatinib progression.

Detailed Description
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HER2-positive breast cancers account for 15%-20% of all breast cancers. The development of HER2 targeted therapies have greatly improved the survival of HER2-positive breast cancer patients. Lapatinib has shown effectiveness in treating HER2-positive metastatic breast cancers, but therapies after lapatinib progression are still controversial. This study is aimed to evaluate the efficacy and safety of pyrotinib after lapatinib progression.

Official Title
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Treatment With Pyrotinib-Based Therapy in Lapatinib Resistant HER2-Positive Metastatic Breast Cancer: A Real World Study

Conditions
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Breast Cancer

Intervention / Treatment
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* Drug: Pyrotinib


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female and 18-70 years old Metastatic or locally recurrent HER2-positive breast cancer Patients received pyrotinib-based therapy after lapatinib failure in treatment for metastasis Complete and accurate medical data Exclusion Criteria: - Incomplete medical data

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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 pyrotinib-based therapy after lapatinib progression. | Drug: Pyrotinib<br>* Pyrotinib-based therapy<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 |