AuthorisedPhase II and Phase III (Integrated)Interventional

C6461004 - A GLOBAL PHASE 2/3 INTERVENTIONAL STUDY OF PF-08634404 IN COMBINATION WITH CHEMOTHERAPY IN PARTICIPANTS WITH EXTENSIVE-STAGE SMALL CELL LUNG CANCER

This important trial, called C6461004, is looking into a new treatment for extensive-stage small cell lung cancer. This is a type of lung cancer that has spread to other parts of the body. The study is testing a new drug, PF-08634404, when given together with common chemotherapy drugs (etoposide and carboplatin) and another medicine called atezolizumab. Researchers want to find out if this combination can shrink tumours, help people live longer, and improve their general well-being. They will also be closely watching for any side effects. This study is split into two main parts, Phase 2 and Phase 3, to gather detailed information about both the effectiveness and safety of the new treatment.

At a glance

Status

Authorised

Phase

Phase II and Phase III (Integrated)

Sponsor

Pfizer Inc.

Enrolment target

182

Start

07 Apr 2026

Extensive-Stage Small Cell Lung Cancer

What is this study about?

This study is designed to explore a new treatment approach for people diagnosed with extensive-stage small cell lung cancer. This means the cancer has spread beyond the lung where it started to other areas of the body. Currently, standard treatments often involve chemotherapy. This study aims to see if adding a new drug, called PF-08634404, to a combination of chemotherapy (etoposide and carboplatin) and an existing cancer medicine (atezolizumab) can lead to better outcomes for patients.

The researchers want to answer a few key questions. Firstly, they want to see if the new drug combination can make tumours smaller or stop them from growing (this is called 'objective response rate'). Secondly, and very importantly, they want to know if this new treatment can help people live longer and improve their overall health and quality of life. They will also be carefully monitoring any side effects to make sure the treatment is as safe as possible.

This study has two main stages, called Phase 2 and Phase 3, which are run together. In Phase 2, the focus is on understanding how well the treatment works and what side effects it might cause. In Phase 3, the goal is to confirm those findings in a larger group of people and compare the new treatment directly to existing options, specifically looking at how long people live with each treatment.

Key takeaways

This study is testing a new treatment combination for extensive-stage small cell lung cancer.
The new drug, PF-08634404, is being combined with chemotherapy and atezolizumab.
Researchers are carefully looking at how well the treatment works and its side effects.
The main goals include improving patient survival and quality of life.
Participation involves regular clinic visits for checks, tests, and treatment.

Who may be eligible?

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

There will be other, more detailed criteria to make sure the study includes people who are likely to benefit from the treatment and can safely receive it. These might include specific health conditions, previous treatments, and certain test results.

A doctor involved with the study will carefully check your medical history and conduct tests to see if this study is suitable for you.

Quick self-check

Are you 18 years old or older?
Do you have extensive-stage small cell lung cancer?
Are you able to attend regular clinic appointments?
Are you comfortable with receiving either the new treatment or a standard treatment?
Are you willing to have medical tests and participate in follow-up?

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

What does participation involve?

If you decide to join this study, you will receive either the new drug combination or the standard treatment. You will have regular visits to the clinic for medical check-ups, blood tests, and scans to monitor your health and how the treatment is working. Doctors and nurses will ask you about any side effects you might be experiencing and how you are feeling generally. You may also be asked to complete questionnaires about your quality of life. The treatment will involve taking medication, likely through infusions (drips) and possibly some orally. The exact number of visits and the full duration of your participation will depend on the study plan and how you respond to the treatment, but these studies can sometimes last for several months or even longer, with ongoing follow-up.

Potential risks and benefits

Taking part in a clinical trial offers potential benefits, such as gaining access to a new treatment before it's widely available and contributing to medical knowledge that could help others. However, there are also potential risks, as the new treatment might have unexpected side effects, or it may not work as well as hoped. All possible risks will be carefully explained to you. Remember, joining a trial is completely voluntary, and you have the right to withdraw at any time without affecting your usual medical care.

Locations (4)

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France
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Italy
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Germany
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Spain

Common questions

What type of cancer is this study for?

This study is for people with extensive-stage small cell lung cancer, which means the cancer has spread.

What new drug is being tested?

The study is testing a new drug called PF-08634404 in combination with other treatments.

What will researchers be looking for?

They want to see if the new treatment can shrink tumours, help people live longer, and improve their general health, while also monitoring side effects.

Who can join this study?

Adults aged 18 and over, both men and women, may be eligible. Specific medical checks will be done to confirm eligibility.

Will I get the new drug or the standard treatment?

Participants will be assigned to either receive the new drug combination or the current standard of care for this condition.