A Randomized, Double-Blind, Phase III Study of Pembrolizumab Versus Placebo in Combination With Neoadjuvant Chemotherapy and Adjuvant Endocrine Therapy for the Treatment of High-Risk Early-Stage Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative (ER+/HER2-) Breast Cancer (KEYNOTE-756)
Overview
- Phase
- Phase 3
- Intervention
- Pembrolizumab (K)
- Conditions
- Breast Cancer
- Sponsor
- Merck Sharp & Dohme LLC
- Enrollment
- 1240
- Locations
- 244
- Primary Endpoint
- Pathological Complete Response (pCR) Rate Using the Definition of ypT0/Tis ypN0
- Status
- Active, not recruiting
- Last Updated
- 9 months ago
Overview
Brief Summary
The purpose of this study is to assess the efficacy and safety of pembrolizumab (MK-3475) versus placebo in combination with neoadjuvant (pre-surgery) chemotherapy and adjuvant (post-surgery) endocrine therapy in the treatment of adults who have high-risk early-stage estrogen receptor-positive, human epidermal growth factor receptor 2-negative (ER+/HER2-) breast cancer.
The primary study hypotheses are: 1) pembrolizumab is superior to placebo, both in combination with the protocol-specified neoadjuvant anticancer therapy, as assessed by pathological Complete Response (pCR) rate defined by the local pathologist, and 2) pembrolizumab is superior to placebo (both in combination with the protocol-specified neoadjuvant and adjuvant anticancer therapies) as assessed by Event-Free Survival (EFS) as determined by the investigator. The study is considered to have met its primary objective if pembrolizumab is superior to placebo with respect to either pCR (ypT0/Tis ypN0) or EFS.
Detailed Description
Study participants will receive 8 cycles of neoadjuvant study treatment and then will undergo surgery for their breast cancer. After surgery, participants will receive 9 cycles of study treatment and up to 10 years of variable endocrine therapy. Each cycle is 21 days long.
Investigators
Eligibility Criteria
Inclusion Criteria
- •Has a localized invasive breast ductal adenocarcinoma, confirmed by the local pathologist, that includes either T1c-T2 (tumor size ≥2 cm), clinical node stage (cN)1-cN2, or T3-T4, cN0-cN
- •Note: Inflammatory breast cancer is allowed.
- •Has centrally confirmed ER+/HER2-, Grade 3 breast cancer of ductal histology, according to the most recent American Society of Clinical Oncology/College of American Pathologist guidelines.
- •Provides a new or recently obtained core needle biopsy, consisting of multiple cores, taken from the primary breast tumor(s) for central determination of HR status (ER and progesterone receptor), HER2, grade, and PD-L1 status.
- •Note: Sponsor agreement is required for formalin-fixed paraffin-embedded (FFPE) tumor tissue sample or slides that were obtained greater than 60 days prior to the date that the documented informed consent was obtained.
- •Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, as assessed within 10 days prior to initiation of study treatment.
- •Male participants must agree to use contraception during the treatment period and for at least 12 months (for participants who received cyclophosphamide) or 6 months (for participants who did not receive cyclophosphamide) after the last dose of study treatment and refrain from donating sperm during this period.
- •Female participants must agree to use effective contraception during the treatment period and for at least 12 months (for participants who received cyclophosphamide) or 6 months (for participants who did not receive cyclophosphamide) after the last dose of study treatment with pembrolizumab or placebo.
- •Has adequate organ function.
Exclusion Criteria
- •Has a history of non-infectious pneumonitis that required treatment with steroids or has current pneumonitis.
- •Has breast cancer with lobular histology.
- •Has bilateral invasive breast cancer.
- •Has metastatic (Stage IV) breast cancer.
- •Has multi-centric breast cancer (presence of more than 1 tumor in different quadrants of the breast).
- •Has any of the following clinical lymph node staging per current American Joint Committee on Cancer (AJCC) staging criteria for breast cancer staging based on radiological and/or clinical assessment: cN3, cN3a, cN3b, or cN3c.
- •Has ER-, progesterone receptor positive breast cancer.
- •Has undergone excisional biopsy of the primary tumor and/or axillary lymph nodes or has undergone sentinel lymph node biopsy prior to study treatment.
- •Has a known additional, invasive, malignancy that is progressing or required active treatment in the last 5 years.
- •Note: Participants with basal cell carcinoma of the skin, squamous cell carcinoma of the skin, ductal breast carcinoma in situ, or cervical carcinoma in situ that has undergone potentially curative therapy are not excluded.
Arms & Interventions
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Pembrolizumab (K)
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Paclitaxel (X)
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Doxorubicin (A)
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Epirubicin (E)
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Cyclophosphamide (C)
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Endocrine therapy
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Radiation therapy
Pembrolizumab+Chemotherapy (KX/KA[E]C)
In the neoadjuvant setting, participants receive pembrolizumab (K) 200 mg via intravenous (IV) infusion once every 3 weeks (Q3W) + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by pembrolizumab 200 mg via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive pembrolizumab 200 mg via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Surgery
Placebo+Chemotherapy (PX/PA[E]C)
In the neoadjuvant setting, participants receive placebo (P; normal saline or dextrose) via IV infusion Q3W + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by placebo via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive placebo via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Placebo (P)
Placebo+Chemotherapy (PX/PA[E]C)
In the neoadjuvant setting, participants receive placebo (P; normal saline or dextrose) via IV infusion Q3W + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by placebo via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive placebo via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Paclitaxel (X)
Placebo+Chemotherapy (PX/PA[E]C)
In the neoadjuvant setting, participants receive placebo (P; normal saline or dextrose) via IV infusion Q3W + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by placebo via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive placebo via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Doxorubicin (A)
Placebo+Chemotherapy (PX/PA[E]C)
In the neoadjuvant setting, participants receive placebo (P; normal saline or dextrose) via IV infusion Q3W + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by placebo via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive placebo via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Epirubicin (E)
Placebo+Chemotherapy (PX/PA[E]C)
In the neoadjuvant setting, participants receive placebo (P; normal saline or dextrose) via IV infusion Q3W + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by placebo via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive placebo via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Cyclophosphamide (C)
Placebo+Chemotherapy (PX/PA[E]C)
In the neoadjuvant setting, participants receive placebo (P; normal saline or dextrose) via IV infusion Q3W + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by placebo via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive placebo via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Radiation therapy
Placebo+Chemotherapy (PX/PA[E]C)
In the neoadjuvant setting, participants receive placebo (P; normal saline or dextrose) via IV infusion Q3W + paclitaxel (X) 80 mg/m\^2 via IV infusion once weekly (QW) for 4 cycles (Treatment 1), followed by placebo via IV infusion + doxorubicin or epirubicin (A or E; 60 mg/m\^2 or 100 mg/m\^2) via IV infusion either in Q2W or Q3W + cyclophosphamide (C) 600 mg/m\^2 via IV infusion either in Q2W or Q3W for 4 cycles (Treatment 2). At no more than 6 weeks after last cycle of neoadjuvant treatment, participants will undergo surgery for their breast cancer. After surgery, participants will begin adjuvant study treatment. In the adjuvant setting, participants receive placebo via IV infusion Q3W for 9 cycles + variable endocrine therapy for up to 10 years. Each cycle is 21 days long.
Intervention: Surgery
Outcomes
Primary Outcomes
Pathological Complete Response (pCR) Rate Using the Definition of ypT0/Tis ypN0
Time Frame: Up to approximately 7 months (Time of surgery)
The pCR rate (ypT0/Tis ypN0) is defined as the percentage of participants without residual invasive cancer on hematoxylin and eosin evaluation of the complete resected breast specimen and all sampled regional lymph nodes following completion of neoadjuvant systemic therapy by American Joint Committee on Cancer (AJCC) staging criteria (8th edition) assessed by the local pathologist at the time of surgery. The percentage of participants with a pathological Complete Response (pCR) using the definition of (ypT0/Tis ypN0) will be presented for pembrolizumab versus placebo, both in combination with the protocol-specified neoadjuvant anticancer therapies.
Event-Free Survival (EFS)
Time Frame: Up to approximately 12 years
EFS is defined as the time from randomization to disease progression that: precludes surgery, results in a local or distant recurrence, results in a second primary malignancy, or death due to any cause whichever occurs first. The EFS following administration of pembrolizumab and placebo, both in combination with the protocol-specified neoadjuvant and adjuvant anticancer therapies, as determined by the investigator will be presented.
Secondary Outcomes
- pCR Rate Using the Definition of ypT0ypN0(Up to approximately 7 months (Time of surgery))
- pCR Rate Using the Definitions of ypT0/Tis ypN0, ypT0/Tis, and ypT0 ypN0 in Participants With a Combined Positive Score [CPS] ≥1(Up to approximately 7 months (Time of surgery))
- OS in Participants With a CPS ≥1(Up to approximately 12 years)
- Number of Participants Experiencing an Adverse Event (AE)(Up to approximately 15 months)
- Number of Participants Experiencing a Serious Adverse Event (SAE)(Up to approximately 17 months)
- Overall Survival (OS)(Up to approximately 12 years)
- Number of Participants Experiencing an Immune-related AE (irAE)(Up to approximately 15 months)
- Number of Participants who Discontinued Study Treatment Due to an AE(Up to approximately 14 months)
- pCR Rate Using the Definition of ypT0/Tis(Up to approximately 7 months (Time of surgery))
- EFS in Participants With a CPS ≥1(Up to approximately 12 years)
- Change from Baseline in European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life (QoL) Questionnaire Core 30 (QLQ-C30) Score(Baseline (Cycle 1 Day 1 in Treatment 1) and Cycles 1 and 4 Day 1 in Treatment 2 (Up to approximately 5 months) Each cycle is 21 days.)
- Change from Baseline in EORTC Breast Cancer-Specific QoL Questionnaire (QLQ-BR23) Score(Baseline (Cycle 1 Day 1 in Treatment 1) and Cycles 1 and 4 Day 1 in Treatment 2 (Up to approximately 5 months) Each cycle is 21 days.)