A Study to Evaluate the Safety and Effectiveness of Trastuzumab Emtansine (T-DM1) as Therapy in Chinese Participants With HER2 Positive Advanced Breast Cancer

Study Overview
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Brief Summary
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This study is a post-marketing, observational, multicenter, prospective study. It will investigate the the safety and effectiveness of T-DM1 in the Chinese population in real-world clinical practice.

Official Title
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An Observational Study to Evaluate the Safety and Effectiveness of Trastuzumab Emtansine (T-DM1) as Second- or Later-Line Therapy in Chinese Patients With HER2 Positive Advanced Breast Cancer

Conditions
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Breast Cancer

Intervention / Treatment
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* Drug: Trastuzumab emtansine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosed with HER2-positive, unresectable locally advanced or metastatic breast cancer before the start of T-DM1 treatment Had prior treatment for breast cancer which must contain a taxane and trastuzumab Get the treatment of T-DM1 for the first time after diagnosis of breast cancer Exclusion Criteria: Patients not receiving treatment for HER2-positive breast cancer with T-DM1 according to standard of care and in line with the current summary of product characteristics (SPC)/local labeling Has been previously treated with T-DM1 before current clinical visit Currently participating in any clinical trials Previously participated in any clinical trials investigating anti-HER2 drug within 1 year of the initiation of T-DM1

Ages Eligible for Study
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Minimum Age: 18 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 |
| --- | --- |
| Participants with HER2-positive Advanced Breast Cancer<br>Participants will be prospectively followed from the index date (the first treatment of T-DM1) for up to 1 year. | Drug: Trastuzumab emtansine<br>* Trastuzumab emtansine will be administered as per local clinical practice and local labeling.<br>* Other names: T-DM1;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants with Adverse Events |  | Up to approximately 1 year from index date | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Real-world Progression Free Survival (rwPFS) |  | From the index date to the date of first progression of disease as recorded in rwTR or death due to any reason, whichever occurs first (up to approximately 1 year from index date) | 
| Time-to-treatment Discontinuation (TTD) |  | Up to approximately 1 year from index date | 
| Percentage of Participants Exposed to T-DM1 by Line of Therapy |  | Up to approximately 1 year from index date | 
| Percentage of Participants Exposed to T-DM1 by Dosage |  | Up to approximately 1 year from index date | 
| Percentage of Participants Exposed to T-DM1 by Dose Intensity |  | Up to approximately 1 year from index date | 
| Percentage of Participants Exposed to T-DM1 by Duration |  | Up to approximately 1 year from index date | 
| Percentage of Participants Exposed to Prior and Concomitant Medication by WHODrug Anatomical Therapeutic Chemical (ATC) Classification System |  | Up to approximately 1 year from index date | 
| Percentage of Participants Exposed to Prior and Concomitant Surgery/Procedure by Medical Dictionary for Regulatory Activities (MedDRA) |  | Up to approximately 1 year from index date |