Active not recruitingPHASE3INTERVENTIONAL

A Study of DB-1303/BNT323 vs Investigator's Choice Chemotherapy in HER2-Low, Hormone Receptor Positive Metastatic Breast Cancer (DYNASTY-Breast02)

This research trial, called DYNASTY-Breast02, is testing a new medication called DB-1303/BNT323. It's for people with advanced breast cancer that has spread to other parts of the body (metastatic breast cancer). Specifically, it's for those whose cancer has certain characteristics: it's 'HER2-low' and hormone receptor-positive. The study aims to find out if this new drug is better than standard chemotherapy at stopping the cancer from growing or getting worse. Doctors will compare how long people on the new drug live without their cancer progressing, against those receiving common chemotherapy treatments. Over 500 people will take part globally, helping us learn more about this potential new treatment option.

At a glance

Status

Active not recruiting

Phase

PHASE3

Sponsor

DualityBio Inc.

Enrolment target

541

Start

18 Jan 2024

Estimated completion

01 Aug 2028

Metastatic Breast Cancer

What is this study about?

This study is investigating a new treatment for a specific type of advanced breast cancer. When breast cancer is advanced, it means it has spread to other parts of the body. The cancer types being studied here are described as 'HER2-low' and 'hormone receptor-positive'. HER2-low means the cancer cells have a small amount of a protein called HER2, but not enough to be considered 'HER2-positive'. Hormone receptor-positive means the cancer growth is often driven by hormones like oestrogen or progesterone.

The main goal of this trial is to see if a new drug, called DB-1303/BNT323, can stop this type of cancer from growing for longer periods compared to standard chemotherapy treatments. This is important because current treatments don't always work for everyone, and finding new options can improve people's lives. Researchers will carefully compare how well the new drug works against commonly used chemotherapy drugs such as capecitabine, paclitaxel, or nab-paclitaxel.

About 532 people worldwide are expected to take part. They will be randomly assigned to receive either the new drug or one of the standard chemotherapy options. This will help doctors understand the benefits and any side effects of the new treatment, ultimately aiming to provide more effective options for people living with HER2-low, hormone-positive metastatic breast cancer.

Key takeaways

This study tests a new drug for advanced, HER2-low, hormone-positive breast cancer.
It compares the new drug to standard chemotherapy to see if it stops cancer growth longer.
Participation requires your cancer to have specific characteristics and previous hormone treatment.
You will be randomly assigned to receive either the new drug or a standard chemotherapy.
Regular hospital visits, tests, and scans will monitor your health and cancer's response.
You can leave the study at any time without affecting your future medical care.

Who may be eligible?

To join this study, you need to be an adult, aged 18 or over. You must have advanced breast cancer that has spread. A very important point is that your cancer must be both 'HER2-low' and 'hormone receptor-positive'. This will be checked by special lab tests on a sample of your tumour.

You also need to have received previous hormone treatment for your advanced cancer which has now stopped working. This could mean your cancer got worse within six months of starting initial hormone therapy plus a specific type of drug (CDK4/6 inhibitor), or your cancer progressed after at least two other lines of hormone therapy for advanced disease. You shouldn't have had chemotherapy for your advanced breast cancer before, but it's okay if you had chemotherapy early on for your breast cancer, as long as it's been more than 12 months since you finished it and your advanced cancer was diagnosed.

Researchers will also check your general health and how well you can perform daily activities (your 'performance status'), making sure you are well enough to participate. You will also need to have at least one measurable tumour spot, which doctors can track to see if the treatment is working.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you an adult aged 18 or over?
Do you have advanced breast cancer that has spread?
Has your doctor confirmed your cancer is 'HER2-low' and 'hormone receptor-positive'?
Has your cancer progressed despite previous hormone-based treatments for advanced disease?
Have you NOT received chemotherapy for your advanced breast cancer before?
Are you generally well enough to participate in a clinical study?

Answer every question to see your result.

What does participation involve?

If you join this study, you would be randomly assigned to receive either the new drug, DB-1303/BNT323, or one of the standard chemotherapy options (capecitabine, paclitaxel, or nab-paclitaxel). This means you wouldn't get to choose which treatment you receive. You would continue treatment for as long as it is working and you are not experiencing unacceptable side effects. Many tests and visits will be involved to monitor your health and the cancer's response.

Throughout the study, you'll have regular hospital visits for check-ups, blood tests, and scans (like CT or MRI scans) to see how the treatment is affecting you and your cancer. These scans will help doctors measure the cancer and see if it's shrinking, staying the same, or growing. The exact number of visits and tests will be explained by the study team, but they are crucial for monitoring your safety and the effectiveness of the treatment. The total duration of your participation would depend on how your cancer responds and how well you tolerate the treatment.

Potential risks and benefits

Taking part in a clinical trial offers the potential benefit of accessing a new treatment before it's widely available, which might be more effective for your cancer. However, all treatments carry potential risks, including side effects from the study drug or standard chemotherapy. These side effects can vary from mild to severe, and the study team will monitor you closely and explain what to expect. There's also the chance that the new treatment might not work for you, or that the standard treatment might be more effective. Your safety and well-being are a priority, and you are free to withdraw from the study at any time, for any reason, without it affecting your future medical care.

Locations (258)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

Research Site 1141-0
Verified postcode
Tucson, United States
Research Site 1114-0
Verified postcode
Fullerton, United States
Research Site 1107-0
Verified postcode
Los Angeles, United States
Research Site 1118-0
Verified postcode
Orange, United States
Research Site 1143-0
Verified postcode
Sacramento, United States
Research Site 1132-0
Verified postcode
Santa Barbara, United States
Research Site 1137-0
Verified postcode
Aurora, United States
Research Site 1129-0
Verified postcode
Lone Tree, United States
Research Site 1154-0
Verified postcode
Jacksonville, United States
Research Site 1145-0
Verified postcode
Miami, United States
Research Site 1150-0
Verified postcode
Orange City, United States
Research Site 1125-0
Verified postcode
Palm Bay, United States

Common questions

What does 'HER2-low' and 'hormone receptor-positive' mean for my breast cancer?

These are specific features of your cancer cells. HER2-low means you have a small amount of a protein called HER2, and hormone receptor-positive means your cancer growth is often affected by hormones.

What is the new drug DB-1303/BNT323?

It's an investigational medication being tested to see if it can stop advanced breast cancer (HER2-low, hormone receptor-positive) from growing for longer periods compared to current standard treatments.

Will I get to choose my treatment?

No, in this study, you would be randomly assigned to either receive the new drug or one of the standard chemotherapy options. This is a common method in trials to ensure fair comparison.

How long will I be in the study?

You'll continue treatment as long as it's working for your cancer and you're not experiencing difficult side effects. The exact duration varies for each person.

What happens if the treatment isn't working or I feel unwell?

The study team will closely monitor you. If the treatment isn't helping or if side effects become too severe, you will stop the study treatment and discuss other options with your doctor. You can also leave the study at any time.