Outcome of Tucidinostat-Based Therapy in HR+ Metastatic Breast Cancer Patients Previously Treated With CDK4/6 Inhibitor

Study Overview
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Brief Summary
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To evaluate the efficacy of tucidinostat-based therapy in hormone receptor-positive metastatic breast cancer patients previously treated with CDK4/6 inhibitor therapy in the real world.

Detailed Description
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Cyclin-dependent kinase (CDK) 4/6 inhibitors have changed the treatment pattern of patients with hormone receptor-positive HER2-negative advanced breast cancer significantly prolongling patients'PFS and OS,but there is no optimal therapy after its progression.Tucidinostat (formerly known as chidamide) is an oral subtype-selective histone deacetylase inhibitor, ACE trial demonstrated that tucidinostat plus exemestane improved PFS compared with placebo plus exemestane in HR+,MBC patients that progressed after previous endocrine therapy,only 7 patients enrolled in the trial had previously received CDK4/6 inhibitors.The aim of this trial is to evaluate the efficacy of tucidinostat-based therapy in hormone receptor-positive metastatic breast cancer patients previously treated with CDK4/6 inhibitor therapy in the real world.

Official Title
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A Single-center Study of the Outcome of Tucidinostat-Based Therapy in Hormone Receptor-Positive Metastatic Breast Cancer Patients Previously Treated With CDK4/6 Inhibitor Therapy

Conditions
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Breast Cancer

Intervention / Treatment
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* Drug: Tucidinostat


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1.woman, age > 18 years old 2.Diagnosed with HR+/HER2- Metastatic Breast Cancer 3.Patients received tucidinostat-based therapy after progression on CDK4/6 inhibitor 4.Complete medical history was available Exclusion Criteria: 1.Medical history was incomplete

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 |
| --- | --- |
| Tucidinostat-based therapy<br>30 mg tucidinostat was given orally(as six 5 mg tablets per day) twice a week (either, Monday and Thursday, Tuesday and Friday, or Wednesday and Saturday) for 4 consecutive weeks in a 4-week cycle.The endocrine drugs combined with tucidinostat were given based on previous treatment.Patients received tucidinostat-based treatment until disease progression or intolerable adverse events. | Drug: Tucidinostat<br>* Tucidinostat in combination with endocrine drugs<br>* Other names: Chidamide;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PFS | Progression free survival | 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adverse events | Number of participants with treatment-related adverse events as assessed by Common Terminology Criteria for Adverse Events version 5.0 (CTCAE v5.0) | 6 weeks |