Diagnosed with Colorectal Cancer?

What is Pumitamig?

Pumitamig is an investigational cancer medicine called a bi‑specific antibody. This means it is designed to attach to two different proteins in the body at the same time to help the immune system fight cancer.

• The immune system and cancer:
  The immune system is the body’s natural defense against disease. Cancer cells can sometimes hide from the immune system, allowing them to grow and spread.
• Role of PD‑L1:
  Some cancer cells use a protein called PD‑L1 to hide from the immune system. When PD‑L1 is active, immune cells have a harder time seeing and attacking cancer cells.
• How PD‑L1 targeting may help:
  One part of pumitamig attaches to PD‑L1. By blocking PD‑L1, pumitamig may help the immune system better recognize and attack cancer cells.
• Role of VEGF‑A:
  Cancer cells and normal cells make a protein called VEGF‑A, which helps form new blood vessels. Tumors can use these blood vessels to grow and can also use VEGF‑A to make it harder for the immune system to work properly.
• How VEGF‑A targeting may help:
  The other part of pumitamig attaches to VEGF‑A. Blocking VEGF‑A may help normalize blood vessel growth and make it easier for immune cells to reach and attack tumor cells.
• How pumitamig is thought to work overall:
  By targeting both PD‑L1 and VEGF‑A, pumitamig is designed to help the immune system better see cancer cells and improve its ability to attack them. This combination is being studied to see how it may help slow or stop tumor growth in many different tumor types.
• What is known so far:
  Pumitamig has been shown to slow tumor growth in laboratory studies and in some studies involving people.

How many patients will be involved?

Globally, approximately 990 patients will participate.

How long is the study?

If you enroll, the length of time you're on treatment depends on how your cancer responds — treatment continues until your cancer progresses, side effects become too difficult, or you choose to stop. After treatment, the study continues to follow participants for safety and survival, for up to about 5 years total from when the last patient joined.

Will I know which drug I'm taking?

This is a blinded, randomized study.

• "Blinded" means that you and your study team will not know which drug you're getting.
• "Randomized" means you'll be placed randomly, like a flip of a coin, into one of two groups.
• All patients will receive chemotherapy along with either pumitamig or bevacizumab.

Study period details

Before joining, the study doctor will run tests to confirm your cancer meets the study's requirements, including a tumor sample and biomarker testing.

Screening period:

The study doctor will conduct a series of tests and assessments to confirm a patient meets the specific criteria for participation in the study. Eligible patients will then be enrolled in the study if they agree to participate and sign an informed consent form. If any of the tests show that you are not the right fit to be part of the study, your study doctor will explain why.

Treatment period:

Those who continue will receive either the investigational drug (pumitamig) or the currently approved drug (bevacizumab), both combined with standard chemotherapy given through an IV. Treatment continues on a regular cycle until your cancer gets worse or you can no longer tolerate the treatment.
Follow-up period, end of treatment, safety follow-up, long-term follow-up:
If you stop the study drugs, you will continue to meet with your study team to follow your disease status and any side effects.

• If your disease does not respond well to the study treatment or the treatment stops working, your doctor will talk to you about other treatment options.
• You will also have two safety follow-up visits — about 30 days and 90 days after treatment ends — and then a check-in about every 3 months after that to see how you're doing, for the rest of the study.

Frequently Asked Questions

For patients and caregivers researching this clinical trial

1. What is ROSETTA CRC-203?

ROSETTA CRC-203 is a research study comparing two treatments — a new drug called pumitamig plus chemotherapy, versus a currently used drug called bevacizumab plus chemotherapy — for people with colorectal cancer that has spread or can't be removed with surgery. It's being run at multiple hospitals and cancer centers around the world, including in the U.S., and is sponsored by Bristol-Myers Squibb and BioNTech.

2. What is pumitamig?

Pumitamig is a new type of drug designed to do two things at once: help the immune system recognize cancer cells, and block a signal that helps tumors grow new blood vessels. It's still being studied and hasn't been approved for regular use yet.

3. What is the study trying to find out?

Researchers want to know if pumitamig, combined with chemotherapy, helps patients live longer without their cancer growing or spreading, compared to the current standard treatment (bevacizumab plus chemotherapy). They're also looking at overall survival and how well tumors respond to treatment.

4. Who can join this study?

This study is for people who have colorectal cancer that has come back, spread, or can't be surgically removed, and who have not yet received treatment for it. It's only for people who haven't started chemotherapy yet for their advanced cancer — so it's important to ask about it early, before treatment begins. Your doctor can help determine if you qualify.

5. What treatment would I get, and how is that decided?

If you join the study, you'll be randomly placed into one of two groups — like a coin flip — to receive either pumitamig or bevacizumab, both given along with standard chemotherapy.

6. Will I know which treatment I'm getting?

No. This is a "blinded" study, which means neither you nor your care team will know which of the two treatments you're receiving. This helps researchers compare the treatments fairly.

7. Is this study still accepting patients?

Yes, the study is currently recruiting at various locations and is open to adults 18 and older.

8. How do I know if this study might be right for me?

Every patient's cancer is different, and eligibility depends on details only your doctor can check. The best next step is to talk to your oncologist about whether a first-line study like ROSETTA CRC-203 could be an option for you — ideally before you start any chemotherapy.

9. Where can I learn more or find a location near me?

You can look up the official study listing using the ID NCT07221357 on ClinicalTrials.gov, or ask your cancer care team if there's a participating site near you.