Cetuximab (Erbitux, Eli Lilly) is a monoclonal antibody directed against epidermal growth factor receptor (EGFR). It is used in the treatment of EGFR-expressing colorectal cancer (CRC) and is administered as an IV infusion. This section covers the most commonly reported adverse reactions in cetuximab clinical trials as well as warnings, precautions and contraindications.
Common adverse reactions
Warnings and precautions
Drug interactions and other contraindications
Cetuximab common adverse reactions
Adverse reactions reported by at least 25% of clinical trial participants treated with cetuximab include cutaneous adverse reactions (pruritus, or itch, and rash), headache, diarrhea and infection.)
Cetuximab warnings and precautions
Infusion reactions were reported in about 3% of clinical trial participants. Cetuximab infusion should be immediately and permanently discontinued in patients experiencing serious infusion reactions.
Other potentially serious adverse events associated with cetuximab include:
- interstitial lung disease (ILD), a group of diseases that result in thickening and fibrosis of the lung parenchyma;
- acneiform rash, a red papular rash that may form pustules on the face, neck and trunk and can result in secondary bacterial infections;
- mucocutaneous reactions, including SJS and TEN (Figure 2); and
- electrolyte imbalances, including hypomagnesemia.
Figure 2. Toxic epidermal necrolysis (TEN).
Cetuximab drug interactions and other contraindications
Considering these warnings and precautions, cetuximab therapy should be interrupted in patients experiencing symptoms of ILD. Patients with acneiform rash should be monitored for signs of infection, and electrolytes should be monitored in all patients during treatment and for 8 weeks after completion of treatment.
Because of its mechanism of action, cetuximab should only be used in patients with KRAS wild-type, EGFR-expressing metastatic CRC; it is not indicated in patients with mutant RAS (KRAS or NRAS genes) or in those with unknown RAS status.