Active not recruitingPHASE3INTERVENTIONAL

A Study of Tucatinib vs. Placebo in Combination With Ado-trastuzumab Emtansine (T-DM1) for Patients With Advanced or Metastatic HER2+ Breast Cancer

This study is investigating a new treatment for advanced HER2-positive breast cancer. This is a type of breast cancer where the cells have too much of a protein called HER2, which helps them grow. The study will combine a new drug, tucatinib, with an existing treatment called T-DM1. Researchers want to find out if this combination works better than T-DM1 by itself in slowing down or stopping the cancer from growing. This is for breast cancer that has spread to other parts of the body (metastatic) or can't be completely removed by surgery. Participants will either get tucatinib or a dummy pill (placebo) alongside T-DM1. Neither the patient nor their doctor will know which they are receiving, making the study fair and unbiased.

At a glance

Status

Active not recruiting

Phase

PHASE3

Sponsor

Seagen, a wholly owned subsidiary of Pfizer

Enrolment target

466

Start

02 Oct 2019

Estimated completion

10 Mar 2029

HER2-positive Breast Cancer

What is this study about?

This study is for people with a specific type of breast cancer called HER2-positive breast cancer. This means the cancer cells have a particular protein called HER2, which helps them grow. The cancer being studied here is advanced, meaning it has either spread to other areas of the body (this is called metastatic cancer) or it's located in a way that surgery can't fully remove it.

The main aim of this study is to see if a new drug called tucatinib, when given together with a standard treatment called T-DM1, is more effective than T-DM1 alone. T-DM1 is already used to treat HER2-positive breast cancer. Researchers want to find out if adding tucatinib can help slow down the cancer's growth or shrink it more effectively, hopefully leading to better outcomes for patients.

Taking part in this study means you would receive T-DM1, as all patients in the study do. On top of this, you would be randomly assigned to receive either the new drug tucatinib or a placebo. A placebo is a dummy pill that looks like the real thing but contains no medicine. This helps researchers fairly compare how well tucatinib works. Because it's a 'blinded' study, neither you nor your doctor will know whether you're getting tucatinib or the placebo. This helps ensure the results are as accurate as possible.

Key takeaways

This study is testing a new drug, tucatinib, for advanced HER2-positive breast cancer.
It combines tucatinib with a standard treatment, T-DM1, to see if it works better than T-DM1 alone.
Some patients will get tucatinib, others a dummy pill (placebo); neither you nor your doctor will know which.
Participation involves regular clinic visits for blood tests, scans, and to receive T-DM1 injections.
You will take pills (tucatinib or placebo) twice daily at home.
You can stop participating in the study at any time without affecting your medical care.

Who may be eligible?

To join this study, you must have HER2-positive breast cancer that has been confirmed through tests, and it needs to be either advanced (meaning it can't be operated on) or has spread to other parts of your body. You should have already been treated with certain other breast cancer drugs, specifically a taxane and trastuzumab, at some point in your cancer journey.

Your general health and physical ability will also be checked. For instance, doctors will assess how well you can carry out everyday activities. The study also has specific requirements regarding brain health. You might be able to join if you have no brain metastases, or if you have treated or untreated brain metastases that are stable or don't currently need urgent treatment.

However, you won't be able to join if you've already taken certain other drugs similar to tucatinib, such as afatinib or trastuzumab deruxtecan. Also, if you've taken lapatinib or neratinib in the past 12 months (unless it was for a very short time and stopped for reasons other than the cancer getting worse), you usually won't be able to participate. The study is open to both men and women aged 18 and older.

Quick self-check

Have I been diagnosed with HER2-positive breast cancer?
Is my breast cancer advanced (cannot be fully removed by surgery) or has it spread?
Have I previously been treated with the drugs trastuzumab and a taxane?
Am I generally well enough to manage daily activities without much difficulty?
Do I meet the specific criteria regarding brain metastases, if I have them?
Have I avoided certain similar drugs like tucatinib, afatinib, or taken lapatinib/neratinib in the last 12 months?

This is a guide only — the research team will confirm whether you can take part.

What does participation involve?

If you decide to take part, you'll be assigned by chance (like flipping a coin) to one of two groups. Both groups will receive the standard treatment T-DM1 through injections. One group will also take tucatinib pills, and the other will take placebo pills (dummy pills with no medicine). You will take either tucatinib or placebo pills twice a day, every day. T-DM1 injections will be given by the study staff on the first day of each treatment cycle. Each treatment cycle lasts 21 days.

You will have regular check-ups to see how you are doing and how the treatment is working. For the first 24 weeks, you'll have appointments every 6 weeks. After that, they will be every 9 weeks. These appointments will check if your cancer has progressed or if you are having any side effects. You will continue with the study treatment until your cancer gets worse, you have too many side effects, you decide to stop, or the study ends. Even after you stop the study treatment, you will continue to have follow-up appointments to monitor your health and survival until the study officially closes.

Potential risks and benefits

Participating in this study might offer potential benefits, such as access to a new drug (tucatinib) that could potentially improve your treatment for HER2-positive breast cancer. However, there's always a risk that the new treatment may not work for you, or you might experience side effects. All possible side effects will be carefully monitored. You have the right to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (486)

University of South Alabama Health Children's and Women's Hospital
Mobile, United States
University of South Alabama Mitchell Cancer Institute
Mobile, United States
University of South Alabama Health University Hospital
Mobile, United States
Banner Gateway Medical Center
Gilbert, United States
Banner MD Anderson Cancer Center
Gilbert, United States
Western Regional Medical Center, LLC
Goodyear, United States
Arizona Oncology Associates, PC - HOPE.
Tucson, United States
Arizona Oncology Associates, PC - HOPE
Tucson, United States
Arizona Oncology Associates, PC - HOPE
Tucson, United States
UCLA Hematology/Oncology - Alhambra
Alhambra, United States
Kaiser Permanente Medical Center Lab Drawing Station
Antioch, United States
Kaiser Permanente Medical Center Lab Drawing Station
Antioch, United States

+474 more sites — see the official record for the full list.

Common questions

What is HER2-positive breast cancer?

HER2-positive breast cancer is a type where the cancer cells have too much of a protein called HER2, which makes them grow and spread more quickly. Treatments often target this protein.

What is a placebo?

A placebo is a 'dummy' pill that looks just like the real medicine but contains no active drug. It's used in studies to help researchers fairly compare the effects of the new drug.

Will I know if I'm getting the new drug or the placebo?

No, in this study, neither you nor your doctor will know if you are receiving the new drug (tucatinib) or the placebo. This helps ensure the study results are fair and unbiased.

How long will I be in the study?

You will continue receiving the study treatment until your cancer gets worse, you experience too many side effects, you choose to stop, or the study ends. After stopping treatment, you will still have follow-up appointments to monitor your health.

Can I stop participating if I want to?

Yes, absolutely. You have the right to leave the study at any time, for any reason, without it affecting your regular medical care.