The Compassher2 Trials (Comprehensive Use Of Pathologic Response Assessment To Optimize Therapy In Her2-Positive Breast Cancer): Compassher2 Residual Disease (Rd), A Double-Blinded, Phase III Randomized Trial Of T-Dm1 And Placebo Compared With T-Dm1

This study is for participants with human epidermal growth factor receptor 2 (HER2)-positive breast cancer who have already received treatment with chemotherapy and anti-HER2 targeted therapies followed by surgery. At the time of the surgery, cancer was still present in the breast and/or lymph nodes and was surgically removed.

This study is designed to determine if the combination of T-DM1 and a newer drug, tucatinib, are better than usual treatment with T-DM1 alone at preventing cancer from returning. The study will help determine if this approach is better or worse than the usual approach for breast cancer. The usual approach is defined as care most people get for breast cancer.

The usual treatment for patients who are not in a study is treatment with FDA-approved treatments (chemotherapy, anti-HER2 targeted therapies) followed by surgery. If there is tumor remaining after chemotherapy and anti-HER2 targeted therapies, the usual treatment is to receive an FDA-approved intravenous drug called T-DM1. Additional treatment may also include radiotherapy and/or medications to block the activity of estrogen.

This study has public funding from the National Cancer Institute (NCI), part of the National Institutes of Health (NIH) in the United States Department of Health and Human Services.

Inova Schar Cancer Institute
8081 Innovation Park Drive
Fairfax, VA 22031
A department of Inova Fairfax Hospital

Inova Schar Cancer Institute, Fair Oaks Clinic
3580 Joseph Siewick Dr.
Fairfax, VA 22033

• Adults over the ages of 18
• HER2-positive status
• Participants with residual HR-negative, HER2+ disease in the breast and/or lymph nodes per the surgical pathology report are eligible; however, patients with HR+ HER2+ cancers must have node-positive residual disease per the surgical pathology report in order to qualify for the study. The presence of residual invasive disease in the breast is not mandatory for these participants. Note: The presence of micrometastases in lymph nodes after preoperative therapy counts as residual disease, whereas the presence of isolated tumor cells does not
• Participants must have received neoadjuvant chemotherapy with one of the following regimens: THP, TMP, AC-TH(P); TCH(P); FAC-TH(P), or FEC-TH(P). Note: apart from TCHP, where T is docetaxel, treatment with docetaxel or paclitaxel is acceptable
• Additional eligibility in protocol

• Pregnancy/breastfeeding
• T1a/bN0 tumors
• Prior receipt of T-DM1 in the neoadjuvant setting
• Participants with known active and/or untreated Hepatitis B or Hepatitis C or chronic liver disease are ineligible. Participants with a diagnosis of Hepatitis B or C that has been treated and cleared and have normal liver function are eligible to participate in the study if the other eligibility parameters are met
• Additional ineligibility in protocol

Additional information can be found at: https://clinicaltrials.gov/ct2/show/NCT04457596