Study in Participants With Early-Stage or Locally Advanced Human Epidermal Growth Factor Receptor (HER) 2-Positive and Estrogen Receptor/Progesterone Receptor Negative Breast Cancer to Evaluate the Efficiency and Safety of Treatment With Trastuzumab Plus (+) QL1209/Pertuzumab + Docetaxel.

Study Overview
=================
Brief Summary
-----------------
This is a randomized, double-blind, multicenter trial，parallel control designed to evaluate treatment with trastuzumab + QL1209 + docetaxel compared with trastuzumab + pertuzumab + docetaxel in the participants with early-stage or locally advanced HER2-positive and estrogen receptor/progesterone receptor negative breast cancer. The anticipated treatment duration is approximately 140 days.

Detailed Description
-----------------
This is A multi-center, randomized, double-blind, parallel control，comparative clinical trial. The primary objective is to evaluate whether the clinical efficacy of QL1209 and pertuzumab are similar in patients with early-stage or locally advanced HER2-positive and estrogen receptor/progesterone receptor negative breast cancer. The secondary objective are to evaluate whether the clinical safety and immunogenicity of QL1209 and pertuzumab are similar in patients with early-stage or locally advanced HER2-positive and estrogen receptor/progesterone receptor negative breast cancer.

Official Title
-----------------
A Randomized, Multicenter, Double-Blind, Parallel-Controlled, Phase III Clinical Study to Evaluate QL1209/Pertuzumab in Combination With Docetaxel in Patients With Early-Stage or Locally Advanced HER2-Positive and ER/PR-negative Breast Cancer.

Conditions
-----------------
Breast Cancer

Intervention / Treatment
-----------------
* Drug: Trastuzumab
* Drug: QL1209
* Drug: Pertuzumab
* Drug: Docetaxel
* Procedure: surgery


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Volunteer to participate in this clinical study; Completely understand and know this study as well as sign the informed consent form (ICF); Age ≥ 18 years and ≤ 80 years when ICF is signed; Histologically confirmed invasive breast carcinoma with a primary tumor size of more than (>) 2 centimeters (cm) by standard local assessment technique; Breast cancer stage at presentation: early-stage (T2-3, N0-1, M0) or locally advanced (T2-3, N2 or N3, M0; T4, any N, M0); HER2-positive breast cancer confirmed by immunohistochemistry or HER2 gene amplification by in situ hybridization; Estrogen receptor and Progesterone receptor negative. Eastern Cooperative Oncology Group Performance Status equal to or less than (<=) 1. Baseline left ventricular ejection fracture >= 55% measured by echocardiography (preferred) or multiple gated acquisition scan Exclusion Criteria: Stage IV metastatic breast cancer; Inflammatory breast cancer; Previous anti-cancer therapy or radiotherapy for any malignancy; History of malignancies other than colorectal cancer within 5 years prior to randomization, excluding cutaneous basal cell carcinoma, cervical carcinoma in situ, and thyroid papillary adenocarcinoma of non-melanoma after radical treatment; Concurrent anti-cancer treatment in another investigational trial, including hormone therapy, bisphosphonate therapy, or immunotherapy; Major surgical procedure within 4 weeks prior to randomization or from which the participant has not fully recovered; Serious cardiac illness or medical condition; Other concurrent serious diseases that may interfere with planned treatment, including severe pulmonary conditions/illness; Sensitivity to any of the study medications, any of the ingredients or excipients of these medications, or benzyl alcohol; Pregnant or lactating

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Trastuzumab Plus（+） QL1209 + Docetaxel<br>Prior to surgery: trastuzumab, QL1209, and docetaxel for 4 cycles (1 cycle = 21 days) Drug: Docetaxel Drug: QL1209 Drug: Trastuzumab Procedure: Surgery | Drug: Trastuzumab<br>* Trastuzumab IV infusion in 3-week cycles. Neoadjuvant treatment: 8 milligrams per kilogram (mg/kg) loading dose for Cycle 1, followed by 6 mg/kg for Cycles 2-4.<br>* Other names: Herceptin®;Drug: QL1209<br>* QL1209 IV infusion in 3-week cycles. Prior to surgery (neoadjuvant treatment): 840 milligrams (mg) loading dose for Cycle 1, followed by 420 mg for Cycles 2-4.<br>* Other names: Recombinant anti-HER-2 domain Ⅱ humanized monoclonal antibody injection;Drug: Docetaxel<br>* Docetaxel IV infusion in 3-week cycles. Neoadjuvant treatment: 75 mg/m2 for Cycles 1-4<br>* Other names: Docetaxel injection;Procedure: surgery<br>* All participants who are eligible for surgery will undergo surgery and have their pathologic response evaluated.<br>|
| Active Comparator: Trastuzumab Plus（+） Pertuzumab + Docetaxel<br>Prior to surgery: trastuzumab,pertuzumab , and docetaxel for 4 cycles (1 cycle = 21 days) Drug: Docetaxel Drug: Pertuzumab Drug: Trastuzumab Procedure: Surgery | Drug: Trastuzumab<br>* Trastuzumab IV infusion in 3-week cycles. Neoadjuvant treatment: 8 milligrams per kilogram (mg/kg) loading dose for Cycle 1, followed by 6 mg/kg for Cycles 2-4.<br>* Other names: Herceptin®;Drug: Pertuzumab<br>* Pertuzumab IV infusion in 3-week cycles. Prior to surgery (neoadjuvant treatment): 840 milligrams (mg) loading dose for Cycle 1, followed by 420 mg for Cycles 2-4.<br>* Other names: Perjeta®;Drug: Docetaxel<br>* Docetaxel IV infusion in 3-week cycles. Neoadjuvant treatment: 75 mg/m2 for Cycles 1-4<br>* Other names: Docetaxel injection;Procedure: surgery<br>* All participants who are eligible for surgery will undergo surgery and have their pathologic response evaluated.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total pathologic complete response (tpCR) rate | Total pathologic complete response (tpCR) rate, defined as ypT0/is, ypN0 as assessed by an Independent Review Committee (IRC) | Approximately 26 months after randomization of the first patient, when all patients have completed the treatment completion/discontinuation visit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With tpCR as Assessed by the Local Pathologist | This tpCR was assessed by the local pathologist. tpCR is defined as the absence of any residual invasive cancer on hematoxylin and eosin evaluation of the resected breast specimen and all sampled ipsilateral lymph nodes after completion of neoadjuvant therapy and surgery (that is, ypT0/is, ypN0, in accordance with the current American Joint Committee on Cancer [AJCC] staging system). | At surgery | 
| Percentage of Participants With Breast Pathologic Complete Response (bpCR) assessed by the IRC | This bpCR was assessed by the IRC. bpCR is defined as the absence of any residual invasive cancer on the hematoxylin and eosin evaluation of the resected breast specimen after completion of neoadjuvant therapy and surgery (that is, ypT0/is, in accordance with current AJCC staging system). | Approximately 26 months after randomization of the first patient, when all patients have completed the treatment completion/discontinuation visit | 
| Percentage of Participants With bpCR as Assessed by the Local Pathologist | This bpCR was assessed by the local pathologist. bpCR is defined as the absence of any residual invasive cancer on the hematoxylin and eosin evaluation of the resected breast specimen after completion of neoadjuvant therapy and surgery (that is, ypT0/is in accordance with current AJCC staging system). | At surgery | 
| Percentage of Participants With an Objective Response | An objective response was defined as the percentage of participants who achieved a complete response or partial response as the best tumor response during the neoadjuvant period (that is, during Cycles 1-4 prior to surgery), as determined by the investigator on the basis of Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. No confirmation was required for objective response. Only participants with measurable disease at baseline were included in the analysis. The duration of one treatment cycle is 21 days; the administration of therapy in Cycle 5 should not occur until 2 weeks after surgery. | Before surgery |