Cetuximab

What it is and how it works

Mechanism of Action The epidermal growth factor receptor (EGFR, HER1, c-ErbB-1) is a transmembrane glycoprotein that is a member of a subfamily of type I receptor tyrosine kinases including EGFR, HER2, HER3, and HER4. The EGFR is constitutively expressed in many normal epithelial tissues, including the skin and hair follicle. Expression of EGFR is also detected in many human cancers including those of the head and neck, colon, and rectum. Cetuximab binds specifically to the EGFR on both normal and tumor cells, and competitively inhibits the binding of epidermal growth factor (EGF) and other ligands, such as transforming growth factor-alpha.

Mechanism class: HER1 Antagonists

Indications

® is an epidermal growth factor receptor (EGFR) antagonist indicated for treatment of: Head and Neck Cancer Locally or regionally advanced squamous cell carcinoma of the head and neck in combination with radiation therapy. ( 1.1 , 14.1 ) Recurrent locoregional disease or metastatic squamous cell carcinoma of the head and neck in combination with platinum-based therapy with fluorouracil. ( 1.1 , 14.1 ) Recurrent or metastatic squamous cell carcinoma of the head and neck progressing after platinum-based therapy. ( 1.1 , 14.1 ) Colorectal Cancer K-Ras wild-type, EGFR-expressing, metastatic colorectal cancer as determined by an FDA-approved test in combination with FOLFIRI for first-line treatment, in combination with irinotecan in patients who are refractory to irinotecan-based chemotherapy, as a single-agent in patients who have failed oxaliplatin- and irinotecan-based chemotherapy or who are intolerant to irinotecan.

Dosage and administration (summary)

Premedicate with an H 1 receptor antagonist. In Combination With Radiation Therapy: Initial dose: 400 mg/m 2 administered as a 120-minute intravenous infusion one week prior to initiating a course of radiation therapy. Subsequent doses: 250 mg/m 2 administered as a 60-minute infusion every week for the duration of radiation therapy (6–7 weeks). Complete ERBITUX administration 1 hour prior to radiation therapy. As Single-Agent or in Combination With Chemotherapy: Weekly: Administer initial dose of 400 mg/m 2 as a 120-minute intravenous infusion, and subsequent doses of 250 mg/m 2 infused over 60 minutes once weekly.

Contraindications

None. None.

Warnings and precautions

Infusion Reactions: Monitor patients following infusion. Immediately stop and permanently discontinue ERBITUX for serious infusion reactions. ( 2.5 , 5.1 ) Cardiopulmonary Arrest: Monitor serum electrolytes during and after ERBITUX. ( 5.2 , 5.6 ) Pulmonary Toxicity: Interrupt or permanently discontinue for acute onset or worsening of pulmonary symptoms. ( 2.5 , 5.3 ) Dermatologic Toxicity: Monitor for dermatologic toxicities or infectious sequelae. Limit sun exposure.

Pregnancy

Pregnancy Risk Summary Based on findings from animal studies and its mechanism of action , ERBITUX can cause fetal harm when administered to a pregnant woman. There are no available data for ERBITUX exposure in pregnant women.

Storage and supply

Storage and Handling Store vials under refrigeration at 2° C to 8° C (36° F to 46° F). Do not freeze or shake. Increased particulate formation may occur at temperatures at or below 0° C (32° F). Discard any remaining solution in the infusion container after 8 hours at controlled room temperature or after 12 hours at 2° C to 8° C.

Source: Cetuximab (Erbitux) — US FDA prescribing information, 2026-04-16, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.