RecruitingPHASE2INTERVENTIONAL

Investigating Datopotamab Deruxtecan Plus Durvalumab Versus Datopotamab Deruxtecan in Patients With PDL1-negative Metastatic Triple-negative Breast Cancer

This study, called DIAMOND, is looking into new ways to treat advanced triple-negative breast cancer (TNBC) that doesn't have a specific marker called PDL1. TNBC can be challenging to treat, and current standard treatments aren't as effective for the PDL1-negative type. Researchers want to see if combining two drugs, Datopotamab Deruxtecan and Durvalumab, is more effective than Datopotamab Deruxtecan on its own. Datopotamab Deruxtecan targets cancer cells, and Durvalumab helps awaken the body's immune system to fight the cancer. The study will involve around 140 women aged 18 and over in the UK, comparing the two treatment approaches to find out which is better at slowing down or stopping cancer growth.

At a glance

Status

Recruiting

Phase

PHASE2

Sponsor

Queen Mary University of London

Enrolment target

140

Start

27 Oct 2025

Estimated completion

01 Feb 2030

Triple Negative Breast Cancer

What is this study about?

This study, called DIAMOND, is focused on a type of breast cancer known as triple-negative breast cancer (TNBC). This specific type of breast cancer is called 'triple-negative' because the cancer cells don't have three common features (receptors for oestrogen, progesterone, or HER2 protein) that doctors often target with other treatments. This means TNBC can be more difficult to treat, and there's a real need for new and effective therapies, especially for patients whose cancer is advanced or has spread. About 10-15% of all breast cancers are triple-negative.

The study is particularly looking at TNBC that is also 'PDL1-negative'. PDL1 is a protein that can be found on cancer cells and plays a role in how the immune system recognises and fights cancer. For patients with PDL1-negative TNBC, existing standard treatments that combine chemotherapy with immune-boosting drugs haven't shown much benefit. This study aims to find a better treatment option for these patients.

Researchers want to see if combining two specific drugs, Datopotamab Deruxtecan (often shortened to Dato-DXd) and Durvalumab, is more effective than using Datopotamab Deruxtecan alone. Datopotamab Deruxtecan is a 'targeted' drug designed to deliver a powerful medicine directly to cancer cells. Durvalumab is an 'immunotherapy' drug that helps the body's own immune system find and fight cancer cells. It's thought that these two drugs might work well together to combat the cancer. The main goal is to see if the combination treatment can keep the cancer from growing or spreading for longer.

Key takeaways

This study is for advanced, PDL1-negative triple-negative breast cancer.
It compares two drugs (Datopotamab Deruxtecan + Durvalumab) vs. one drug (Datopotamab Deruxtecan).
The main goal is to see if the combination keeps cancer from growing longer.
Participation involves random assignment to a treatment group and regular monitoring.
There's a need for new treatments for this specific type of cancer.

Who may be eligible?

This study is looking for women aged 18 or older who have advanced triple-negative breast cancer that is also 'PDL1-negative'. Your cancer diagnosis would need to be confirmed as triple-negative (meaning it doesn't have oestrogen, progesterone, or HER2 receptors) and also as PDL1-negative by specific tests.

To join, your cancer must be measurable, meaning doctors can track its size and changes using scans like CT or MRI. You'll also need to be well enough to take part in the study, and your blood tests and organ functions (like your liver and kidneys) would need to be within a healthy range. You should also be able to sign a consent form, showing you understand what's involved.

There are also some things that would mean you couldn't join the study, for example, if your bone lesions are only of a particular type (sclerotic/osteoblastic) without other measurable disease, or if you don't meet the specific blood test requirements. The research team would discuss all the detailed criteria with you.

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 a woman aged 18 or older?
Do you have advanced triple-negative breast cancer?
Has your cancer been confirmed as 'PDL1-negative'?
Is your cancer measurable by scans like CT or MRI?
Are you generally well enough to participate, with healthy organ function?

Answer every question to see your result.

What does participation involve?

If you decide to take part in this study, after signing the consent form and having some initial checks, you would be randomly placed into one of two treatment groups, like flipping a coin. You might receive Datopotamab Deruxtecan alone, or you might receive Datopotamab Deruxtecan combined with Durvalumab. You wouldn't be able to choose which group you're in.

Treatment will continue as long as it's helping you and any side effects are manageable. You would stop treatment if the cancer starts to grow, if the side effects become too difficult, or if you decide you no longer want to continue. During the study, you would have regular appointments, blood tests, and scans (like CT or MRI) to check how well the treatment is working and monitor for any side effects. The research team will also assess your general well-being and quality of life throughout your participation.

Potential risks and benefits

Participating in a clinical trial can offer potential benefits, such as access to new treatments before they are widely available, which might be more effective than existing options for your specific condition. However, there are also potential risks, as the investigational drugs may cause side effects, some of which could be serious. The study team will closely monitor you for any adverse effects and will explain all known risks before you agree to participate. It's important to remember that you are free to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (2)

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

Barts Cancer Institute, Centre of Experimental Cancer Medicine
Verified postcode
London, United Kingdom· Not yet recruiting
Barts Health NHS Trust
Verified postcode
London, United Kingdom· Recruiting

Common questions

What is 'triple-negative' breast cancer?

Triple-negative breast cancer means the cancer cells don't have three common markers (oestrogen, progesterone, or HER2 receptors) that other treatments often target.

What does 'PDL1-negative' mean?

PDL1-negative means your cancer cells don't show a specific protein called PDL1. This is important because some immune-boosting drugs work better when this protein is present.

What kind of drugs are being tested?

The study is testing Datopotamab Deruxtecan, a type of targeted drug, and Durvalumab, which is an immunotherapy that helps your immune system fight the cancer. One group will get both, and the other will get only Datopotamab Deruxtecan.

How long will I be in the study?

Treatment will continue as long as it's helping you and you're tolerating it well. You'll have regular check-ups, scans, and tests throughout your participation.

Will I know which treatment I'm receiving?

No, you will be randomly assigned to one of the two treatment groups, and neither you nor your doctor will get to choose which treatment you receive.

How to find out more

Peter Schmid, MD PhD, FRCP

bci-diamond@qmul.ac.uk +44(0)20 7882 8764 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.