AuthorisedTherapeutic confirmatory (Phase III)Interventional

C6461003 - AN INTERVENTIONAL, PHASE 3, DOUBLE-BLIND, RANDOMIZED STUDY TO EVALUATE THE EFFICACY AND SAFETY OF PF-08634404 IN COMBINATION WITH CHEMOTHERAPY VERSUS BEVACIZUMAB IN COMBINATION WITH CHEMOTHERAPY IN TREATMENT-NAÏVE PARTICIPANTS WITH METASTATIC COLORECTAL CANCER

This study, named C6461003, is for people recently diagnosed with bowel cancer that has spread to other parts of the body. It's a key stage of research (Phase 3) to see if a new medicine, PF-08634404, works well and is safe when given with standard chemotherapy. We'll be comparing this new combination against another common treatment, Bevacizumab with chemotherapy. Doctors want to understand which treatment helps people live longer without their cancer growing and how it affects their quality of life. The study design helps ensure fair results by not letting participants or doctors know which specific treatment is being given.

At a glance

Status

Authorised

Phase

Therapeutic confirmatory (Phase III)

Sponsor

Pfizer Inc.

Enrolment target

220

Start

23 Mar 2026

Metastatic Colorectal Cancer

What is this study about?

This clinical trial is designed for people who have recently been diagnosed with bowel cancer that has spread to other parts of their body, known as metastatic colorectal cancer. The main goal is to find out if a new medicine, PF-08634404, can improve treatment outcomes. This new medicine will be given alongside standard chemotherapy. The study will compare this new combination to a treatment that is already commonly used, which is another medicine called Bevacizumab, also given with standard chemotherapy.

The researchers want to see if the new treatment helps people live longer without their cancer getting worse. They will also look at how it affects their overall health and how long people live. Another important aim is to understand the side effects of the new medicine and how it might impact a person's everyday life and wellbeing. This means researchers will pay close attention to any changes in your quality of life, including how you feel and your ability to do daily activities.

This kind of study is called a 'Phase 3' trial, which means it's a critical step before a new medicine can be widely approved. It is also 'double-blind' and 'randomised', which means neither you nor your study doctor will know which of the two treatment combinations you are receiving. This helps make sure the results are as fair and unbiased as possible, so we can get a true picture of how well the new medicine works compared to the existing treatment.

Key takeaways

This study evaluates a new drug, PF-08634404, for advanced bowel cancer.
It compares two treatment combinations: the new drug plus chemotherapy vs. an existing drug (Bevacizumab) plus chemotherapy.
The aim is to find out which treatment is more effective and safer.
You won't know which specific treatment you're receiving (double-blind study design).
Participation involves regular clinic visits, tests, and symptom monitoring.
It could offer access to a new treatment and close medical care.

Who may be eligible?

To join this study, you need to be at least 18 years old. Both men and women can take part.

The study is specifically for people who have bowel cancer that has spread to other parts of their body and have not received any previous treatment for this widespread cancer. Researchers will check other health details to make sure the study is a good fit and safe for you, as well as making sure the results are clear.

It's important to remember that these are just the basic requirements. A doctor or nurse involved in the study will discuss all the specific details with you to see if you meet all the criteria.

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 18 years old or older?
Have you been diagnosed with bowel cancer that has spread?
Have you *not* had any treatment yet for your widespread bowel cancer?
Are you willing to discuss all your health conditions with the study team to see if you qualify?

Answer every question to see your result.

What does participation involve?

If you decide to join this study, you would be randomly assigned to receive one of two treatment combinations: either the new medicine (PF-08634404) plus standard chemotherapy, or the existing medicine (Bevacizumab) plus standard chemotherapy. You will receive these treatments by injection or infusion and also take some medicines by mouth, based on a schedule set by the study team. Both you and your doctors will not know which specific combination you are receiving.

Throughout the study, you will have regular visits to the clinic for medical check-ups, blood tests, scans, and to discuss how you are feeling and any side effects you might experience. You'll also be asked to fill out questionnaires about your quality of life and symptoms. These visits will be more frequent at the beginning and become less frequent over time. The total time you'll be involved in the study will depend on how your treatment is working, but there will be ongoing follow-up to monitor your health and any long-term effects.

Potential risks and benefits

Taking part in a clinical trial offers potential benefits, such as accessing a new treatment before it's widely available and receiving close medical attention. While the new medicine might help control your cancer effectively, it's also possible it won’t work for you, or it may have side effects. All medicines, including those used in this study, can cause side effects, and these will be carefully monitored. The study team will explain all known potential risks and benefits fully. You are free to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (8)

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

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Unverified
Spain
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Unverified
Belgium
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Unverified
France
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Unverified
Italy
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Unverified
Netherlands
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Unverified
Germany
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Unverified
Poland
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Unverified
Denmark

Common questions

What is 'metastatic colorectal cancer'?

This means bowel cancer that has spread from where it started to other parts of your body.

What does 'Phase 3' mean for a study?

Phase 3 is a major step in testing a new medicine. It means the medicine has already shown some promise and is now being compared to existing treatments in a larger group of people to confirm its effectiveness and safety.

Will I know which treatment I'm getting?

No, in this study, neither you nor your doctor will know which of the two treatment combinations you are receiving. This is called 'double-blind' and helps ensure the study results are fair.

What is chemotherapy?

Chemotherapy is a type of cancer treatment that uses powerful chemicals to kill fast-growing cancer cells in the body.

What if I get side effects?

The study team will monitor you very closely for any side effects. You should report anything you experience, and your doctors will help manage them.