A Phase 3 interventional study of PF-08634404 and Bevacizumab in Intestinal Neoplasms, Gastrointestinal Neoplasms and Digestive System Neoplasms, sponsored by Pfizer. Recruiting at 372 sites in 17 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-08.
Sponsored by Pfizer · Phase 3, Interventional, and Treatment
The purpose of this study is to learn more about a new medicine called PF-08634404, and how well it works in people with cancer of the colon or rectum (CRC)). The goal is to understand if the new study medicine, combined with chemotherapy that is approved for colorectal cancer, can help people whose cancer has spread or returned after treatments taken before.
To join the study, participants must meet the following conditions:
Participants will be randomized (like flipping a coin) to one of 2 different treatment arms. The first arm (Arm A) will include the new medicine PF-08634404 in combination with chemotherapy that is approved for colorectal cancer, and the second arm (Arm B) will include an approved medicine for colorectal cancer, called Bevacizumab, in combination with chemotherapy that is approved for this type of cancer. Participants and their doctors will not know which arm they are being assigned to. Participants will receive all the study medications through intravenous (IV) infusions, which means the medicine is given directly into a vein. The treatment will be given in cycles, and participants may continue receiving it if it is helping and they are not experiencing serious side effects.
The medicine will be given at a clinical site, where trained medical staff will check participants during and after each treatment.
6,541 studies on the registry are indexed under Colorectal Neoplasms; 1,667 are open to participants now.
This study's planned enrollment of 800 is above the median of 76 across 4,800 interventional studies indexed under Colorectal Neoplasms.
Browse Colorectal Neoplasms studies →Pfizer is the lead sponsor of 3,334 studies on the registry; 149 are open to participants now.
Of its 601 completed or terminated interventional studies of FDA-regulated products, 391 (65%) have results posted.
Compared within Colorectal Neoplasms, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Intestinal Neoplasms. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Participants are excluded from the study if any of the following criteria apply:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Leptomeningeal disease
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive PF-08634404 intravenously (IV) in combination with Chemotherapy.
Drug: PF-08634404 · Drug: Chemotherapy
Participants will receive bevacizumab IV in combination with Chemotherapy.
Biological: Bevacizumab · Drug: Chemotherapy
Solution for infusion
Injection for intravenous use
Also known as: Avastin
Injection for intravenous use
Progression-free survival (PFS) per Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1) by Blinded Independent Central Review (BICR)
Progression-free survival is defined as the time from the date of randomization to the date of the first documentation of objective progressive disease (PD) assessed by BICR per RECIST 1.1, or death due to any cause, whichever occurs first.
Time frame: Approximately 4 years
Overall survival (OS)
Overall survival defined as the time from the date of randomization to the date of death due to any cause.
Time frame: Approximately 4 years
PFS per RECIST 1.1 by investigator assessment
Progression Free Survival (PFS) is defined as the time from the date of randomization to the date of the first documentation of objective PD assessed by investigator per RECIST 1.1, or death due to any cause, whichever occurs first.
Time frame: Approximately 4 years
Objective Response Rate (ORR) by BICR
The proportion of participants who have a confirmed CR or PR, as best overall response assessed by BICR as per RECIST 1.1.
Time frame: Approximately 4 years
Objective Response Rate (ORR) by investigator
The proportion of participants who have a confirmed CR or PR, as best overall response assessed by investigator as per RECIST 1.1.
Time frame: Approximately 4 years
Duration of Response (DOR) by BICR
The time from the first documentation of objective response (CR or PR that is subsequently confirmed) to the date of the first documentation of PD as determined by BICR assessment per RECIST 1.1, or death due to any cause, whichever occurs first.
Time frame: Approximately 4 years
DOR by investigator
The time from the first documentation of objective response (CR or PR that is subsequently confirmed) to the date of the first documentation of PD as determined by Investigator per RECIST 1.1, or death due to any cause, whichever occurs first.
Time frame: Approximately 4 years
PFS2 (PFS after next-line therapy) by investigator
PFS2 is defined as the time from the date of randomization to the date of second objective disease progression or death due to any cause, whichever occurs first. Second objective disease progression is PD after the start of subsequent anticancer therapy (excluding curative surgery) as assessed by the investigator.
Time frame: Approximately 4 years
Number of Participants with Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)
Time frame: Through 90 days after the last study intervention; Approximately 4 years
Number of Participants With Clinical Laboratory Abnormalities
Time frame: Through 90 days after the last study intervention; Approximately 4 years
Pharmacokinetics (PK): Serum concentration of PF-08634404
Time frame: Approximately 21 months
Immunogenicity: Incidence of positive Anti-Drug Antibody (ADA)
To characterize the immunogenicity of PF-08634404
Time frame: Approximately 21 months
Mean scores and Change from baseline in the global health status/quality of life (QoL) score on the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30)
The EORTC QLQ-C30 is a questionnaire for quantitative measure of health-related quality of life pertinent to participants with a broad range of cancers who are participating in international clinical trials.
Time frame: Approximately 4 years
Mean score change from baseline in participant reported function and symptoms scales per EORTC QLQ-CR29
The EORTC QLQ-CR29 is a supplemental colorectal cancer-specific module with measures of symptoms associated with colorectal cancer.
Time frame: Approximately 4 years
Time to definitive deterioration (TTdD) in the global health status/QoL score on the EORTC QLQ-C30
TTdD is defined as the time from date of randomization to first onset of Patient Reported Outcome (PRO) deterioration without subsequent recovery.
Time frame: Approximately 4 years
Time to definitive deterioration (TTdD) in participant reported function and symptoms per EORTC QLQ-CR29
TTdD is defined as the time from date of randomization to first onset of Patient Reported Outcome (PRO) deterioration without subsequent recovery.
Time frame: Approximately 4 years
Showing the first 100 of 372 sites across 17 countries. Choose a country and city above to see the rest.
Plan to share: Yes — Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.
Data sharing details ↗ · www.pfizer.com
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: Anti-PD-1/Anti-VEGF Bispecific Antibody PF-08634404