An observational study in Metastatic Colorectal Cancer, sponsored by Pfizer. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-02.
Sponsored by Pfizer · Observational
The aim of this study is to learn how doctors treat a type of metastatic colorectal cancer in everyday medical practice. The study focuses on patients whose cancer started on the left side of the colon and does not have specific gene changes called RAS mutations (this is known as RAS wild-type disease). It will assess effectiveness of two common types of targeted treatments: anti-EGFR medicines, which block signals that help cancer cells grow, and anti-VEGF medicines, which block the growth of blood vessels that supply tumors.
This is a real-world study, not a clinical study. This means that researchers will look at what happens when patients receive the treatments prescribed by their own doctor as part of their usual healthcare treatment. In this study, researchers will use information derived and de-identified from cancer clinics across the United States (from the Flatiron Health Analytic Database).
5,755 studies on the registry are indexed under Colorectal Neoplasms; 1,495 are open to participants now.
This study's planned enrollment of 1 is below the median of 250 across 1,261 observational studies indexed under Colorectal Neoplasms.
Browse Colorectal Neoplasms studies →Pfizer is the lead sponsor of 3,331 studies on the registry; 148 are open to participants now.
Of its 600 completed or terminated interventional studies of FDA-regulated products, 391 (65%) have results posted.
Counted across the registry records on this site, refreshed daily.
See eligibility criteria
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.
Left-sided metastatic colorectal cancer RAS wild-type disease Received first-line anti-EGFR- or anti-VEGF-based therapy with chemotherapy Available follow-up in the Flatiron Health database
Exclusion:
BRAF-mutated disease MSI-H or dMMR disease Unknown or mutant RAS status Non-left-sided primary tumor
Patients initiating first-line anti-EGFR therapy combined with standard chemotherapy.
Drug: Anti-EGFR-Based Therapy
Patients initiating first-line anti-VEGF therapy combined with standard chemotherapy.
Drug: Anti-VEGF-Based Therapy
Patients initiating first-line anti-EGFR therapy combined with standard chemotherapy.
Patients initiating first-line anti-VEGF therapy combined with standard chemotherapy.
First-Line Treatment Patterns
Time frame: Up to approximately 13 years, 9 months
Real-World Overall Survival (rwOS)
Time frame: Up to approximately 13 years, 9 months.
Treatment patterns following 1L therapy
Time frame: 13 years, 9 months.
Real-world effectiveness across lines of therapy
Time frame: 13 years, 9 months
No study locations are listed for this record.
Plan to share: No — 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.
Start is estimated for Oct 2026; primary completion for Nov 2027, 13 months later.
How these figures are worked out, and which studies are left out of them.
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 ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.