A Study of SHR6390 in Combination With Letrozole or Anastrozole in Patients With HR Positive and HER2 Negative Advanced Breast Cancer

Study Overview
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Brief Summary
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This is a phase III clinical trial to evaluate the efficacy and safety of SHR6390 in combination with Letrozole or Anastrozole versus placebo in combination with Letrozole or Anastrozole in Patients who have HR positive and HER2 negative recurrent/metastatic breast cancer and have not received systemic anticancer therapy are eligible for this study.

Official Title
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A Phase III Study to Evaluate Efficacy and Safety of SHR6390 in Combination With Letrozole or Anastrozole Versus Placebo in Combination With Letrozole or Anastrozole in Patients With HR Positive and HER2 Negative Recurrent/Metastatic Breast Cancer

Conditions
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Advanced Breast Cancer

Intervention / Treatment
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* Drug: SHR6390 Tablets
* Drug: Placebo Tablets
* Drug: Letrozole or Anastrozole Tablets


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Has the pathologically-confirmed diagnosis of locally recurrent or metastatic, hormone-receptor positive, HER2 negative Breast Cancer. Age: 18 - 75 years old No prior systemic anti-cancer therapy for advanced HR+ disease. Eastern Cooperative Oncology Group [ECOG] 0-1 Exclusion Criteria: Patients who received prior treatment with any CDK4/6 inhibitor. Clinically significant cardiovascular and cerebrovascular diseases, including but not limited to severe acute myocardial infarction within 6 months before enrollment, unstable or severe angina, Congestive heart failure (New York heart association (NYHA) class > 2), or ventricular arrhythmia which need medical intervention.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: SHR6390 in combination with Letrozole or Anastrozole versus placebo in combination with Letrozole or Anastrozole
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SHR6390, Letrozole or Anastrozole<br>SHR6390, Letrozole or Anastrozole | Drug: SHR6390 Tablets<br>* SHR6390 Tablets<br>Drug: Letrozole or Anastrozole Tablets<br>* Letrozole or Anastrozole Tablets<br>|
| Placebo Comparator: Placebo, Letrozole or Anastrozole<br>Placebo, Letrozole or Anastrozole | Drug: Placebo Tablets<br>* Placebo Tablets<br>Drug: Letrozole or Anastrozole Tablets<br>* Letrozole or Anastrozole Tablets<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Investigator-assessed PFS | Investigator-assessed Progression Free Survival | Every 8 weeks from date of enrollment until the date of first documented progression or date of death from any cause, whichever came first, Up to approximately 24 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Progression-free Survival (PFS) per RECIST 1.1 | PFS is defined as the time from randomization to the first documented disease progression per RECIST 1.1 based on blinded independent central review or death due to any cause, whichever occurs first. | Up to approximately 24 months | 
| OS | Overall Survival | up to 2 years | 
| ORR | Objective Response Rate | Up to approximately 24 months | 
| DoR | Duration of Objective Response | Up to approximately 24 months | 
| CBR | Clinical Benefit rate | Up to approximately 24 months | 
| Number of Participants With adverse events (AEs) and serious adverse events (SAEs) Incidence, nature, and severity of adverse events graded according to the NCI CTCAE v5.0 | Number of Participants With adverse events and serious adverse events Incidence, nature, and severity of adverse events graded according to the NCI CTCAE v5.0 | Up to approximately 24 months |