bevacizumab
Avastin (bevacizumab) is a humanised antibody from Roche that binds vascular endothelial growth factor (VEGF). By starving tumours of new blood vessels it slows their growth, and is used with chemotherapy in several advanced cancers, including colorectal and lung cancer.
This page is based on FDA prescribing information and the EMA medicine record for bevacizumab, cross-checked with DailyMed and the National Cancer Institute dictionary; the mechanism is explained in plain language, and analogies are used only where they stay accurate.
How it works
Explains what the medicine does in the body, not dosing, side effects, or safety.
An analogy
A growing tumour is like a town that keeps demanding new roads to bring in supplies, and VEGF is the construction permit. Bevacizumab collects the permits before the road crews ever see them, so no new roads are built and the town's growth stalls on what it already has.
In simple terms
Tumours cannot grow beyond a small size without their own blood supply, so they release VEGF to trigger new vessel growth. Bevacizumab is an antibody that binds VEGF circulating in the blood, stopping it from reaching its receptors on blood vessel cells. New vessel formation slows, the tumour's supply lines are limited, and chemotherapy can work against a less well-fed cancer.
In depth
Bevacizumab is a recombinant humanised IgG1 monoclonal antibody that binds all isoforms of VEGF-A, preventing interaction with VEGFR-1 and VEGFR-2 on endothelial cells. This inhibits tumour angiogenesis, normalises the abnormal tumour vasculature transiently and may improve delivery of co-administered chemotherapy. It does not bind VEGF-B or PlGF. Sustained VEGF blockade underlies both its antitumour activity and its class-typical adverse effects such as hypertension and impaired wound healing.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
How VEGF-blocking medicines starve tumors
- Growing tumors release VEGF, a signal that calls new blood vessels toward them.
- The drug circulates and catches VEGF before it can reach the vessel-wall receptor.
- With VEGF neutralized, the receptor on the endothelial cell is not activated.
- The tumor is starved of new vessels and its growth slows.
Target: Vascular endothelial growth factor (VEGF)
A signalling protein tumours release to grow new blood vessels; those vessels supply oxygen and nutrients the tumour needs to expand and spread.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in United States
FDA- With intravenous fluorouracil-based chemotherapy, for first- or second-line treatment of metastatic colorectal cancer
- With fluoropyrimidine-irinotecan- or fluoropyrimidine-oxaliplatin-based chemotherapy, for second-line treatment of metastatic colorectal cancer that progressed on a prior bevacizumab-containing regimen
- With carboplatin and paclitaxel, for first-line treatment of unresectable, locally advanced, recurrent or metastatic non-squamous non-small cell lung cancer
Approved uses in European Union
EMA- With fluoropyrimidine-based chemotherapy, for metastatic carcinoma of the colon or rectum
- With paclitaxel, for first-line treatment of metastatic breast cancer
- With capecitabine, for first-line treatment of metastatic breast cancer in patients for whom other chemotherapeutic regimens are not suitable
Official sources
The statements on this page trace back to these records.
- Avastin (bevacizumab) — Summary of product characteristics and package leaflet, English version
European Medicines Agency
- DailyMed: Avastin (bevacizumab) label
DailyMed, U.S. National Library of Medicine
- U.S. Food and Drug Administration: bevacizumab prescribing information
U.S. Food and Drug Administration
- National Cancer Institute: bevacizumab
National Cancer Institute
This page explains how the medicine works — it isn’t the patient leaflet. For anything that applies to you, read the leaflet that came with your medicine or ask your pharmacist.
MedUnfold provides educational content and is not medical advice. Always follow your local prescribing information and healthcare professional.