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Tucatinib + T-DM1 for Breast Cancer

Recruiting at 304 trial locations

Overseen BySeagen Trial Information Support

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 3

Waitlist Available

Sponsor: Seagen Inc.

No Placebo Group

Pivotal Trial (Near Approval)

Prior Safety Data

Breakthrough Therapy

Trial Summary

What is the purpose of this trial?

This study is being done to see if tucatinib with ado-trastuzumab emtansine (T-DM1) works better than T-DM1 alone to help patients who have a specific type of breast cancer called HER2 positive breast carcinoma. The breast cancer in this study is either metastatic (spread into other parts of the body) or cannot be removed completely with surgery. Patients in this study will be randomly assigned to get either tucatinib or placebo (a pill with no medicine). This is a blinded study, so neither patients nor their doctors will know whether a patient gets tucatinib or placebo. All patients in the study will get T-DM1, a drug that is often used to treat this cancer. Each treatment cycle lasts 21 days. Patients will swallow tucatinib pills or placebo pills two times every day. Patients will get T-DM1 injections from the study site staff on the first day of every cycle.

Research Team

Pfizer CT.gov Call Center

Principal Investigator

Pfizer

Eligibility Criteria

This trial is for adults with advanced or metastatic HER2+ breast cancer that has worsened after previous treatment or if they couldn't tolerate the last therapy. They should be relatively healthy (ECOG score of 0 or 1) and may have brain metastases if stable, treated, or not requiring immediate intervention. People can't join if they've had certain recent anti-HER2 treatments, large untreated brain lesions, need high-dose steroids for brain symptoms, have leptomeningeal disease, or uncontrolled seizures.

Inclusion Criteria

I am fully active or can carry out light work.

I have been treated with both a taxane and trastuzumab before.

My brain scan shows I may have brain metastases but don't need immediate treatment, or I've been treated for them and am stable or not needing immediate re-treatment.

See 3 more

Exclusion Criteria

I do not have large untreated brain lesions, uncontrolled seizures, or need high doses of steroids for brain symptoms.

I have not been treated with specific HER2 or EGFR targeting drugs recently.

Treatment Details

Interventions

Placebo (Other)
T-DM1 (Antibody Drug Conjugate)
Tucatinib (Kinase Inhibitor)

Trial OverviewThe study tests whether adding tucatinib to T-DM1 (a standard drug for this cancer type) improves outcomes in patients with HER2+ breast carcinoma compared to T-DM1 alone. Participants will either receive tucatinib pills twice daily plus T-DM1 injections every three weeks or placebo pills with T-DM1 injections in a blinded setup where neither patient nor doctor knows which treatment is given.

Participant Groups

2Treatment groups

Experimental Treatment

Active Control

Group I: Tucatinib + T-DM1Experimental Treatment2 Interventions

Tucatinib + T-DM1

Group II: Placebo + T-DM1Active Control2 Interventions

Placebo + T-DM1

T-DM1 is already approved in Canada, Japan, China for the following indications:

Approved in Canada as Kadcyla for:

HER2-positive breast cancer

Approved in Japan as Kadcyla for:

HER2-positive breast cancer

Approved in China as Kadcyla for:

HER2-positive breast cancer

Find a Clinic Near You

Who Is Running the Clinical Trial?

Seagen Inc.

Lead Sponsor

Trials

212

Recruited

73,800+

Founded

1997

Headquarters

Bothell, USA

Known For

Antibody-Drug Conjugates