Pembrolizumab + Standard Therapy for Breast Cancer

Recruiting in Palo Alto (17 mi)

+251 other locations

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 3

Waitlist Available

Sponsor: Merck Sharp & Dohme Corp.

Stay on Your Current Meds

Pivotal Trial (Near Approval)

Prior Safety Data

Breakthrough Therapy

Trial Summary

What is the purpose of this trial?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.

Eligibility Criteria

Adults with high-risk early-stage ER+/HER2- breast cancer, confirmed by a pathologist, who have not received prior treatment for it. Participants must have adequate organ function and an ECOG performance status of 0 or 1. Men and women must agree to use contraception during the study and for some time after. Exclusions include those with certain heart diseases, active infections like hepatitis B/C or tuberculosis, HIV, other cancers within the last five years (except specific non-invasive types), previous immunotherapy treatments, severe allergies to study drugs' components.

Inclusion Criteria

I agree to use contraception and not donate sperm for up to 12 months after treatment.

My breast cancer is ER positive, HER2 negative, Grade 3, and of ductal type.

My breast cancer is invasive, not just on the surface, and is a certain size or has spread to nearby lymph nodes.

+4 more

Exclusion Criteria

I haven't used any experimental drugs or devices within the last 4 weeks, or 12 months if they were for cancer.

I have an active tuberculosis infection.

My breast cancer is estrogen receptor-negative and progesterone receptor-positive.

+20 more

Participant Groups

The trial is testing pembrolizumab's effectiveness compared to a placebo when given alongside pre-surgery chemotherapy and post-surgery endocrine therapy in treating early-stage breast cancer. Success is measured by complete response rate at surgery and event-free survival rates.

2Treatment groups

Experimental Treatment

Placebo Group

Group I: Pembrolizumab+Chemotherapy (KX/KA[E]C)Experimental Treatment8 Interventions

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.

Group II: Placebo+Chemotherapy (PX/PA[E]C)Placebo Group7 Interventions

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.

Cyclophosphamide is already approved in United States, European Union, Canada, Japan for the following indications:

🇺🇸 Approved in United States as Cytoxan for: