Purpose: To confirm the anecdotal observation that patients in North Carolina (NC) and Tennessee (TN) treated with cetuximab experience hypersensitivity reactions (HSR) at a much higher rate than are reported nationally and internationally (<or= 3%).
Patients and methods: Data from patients treated with cetuximab on clinical trials (n = 88) at three research sites were analyzed for grade 3 or 4 HSR. Additional information was obtained from medical records for patients treated with cetuximab at the University of North Carolina (Chapel Hill, NC) to determine whether history of other significant allergy was a risk factor for HSR to cetuximab.
Results: Data for 88 patients on clinical trials and an additional 55 patients treated outside of trials were included in this analysis. Patients had a variety of tumor types. For the clinical trial group (n = 88), the overall rate of grade 3 to 4 HSR was 22%, significantly higher than the rate noted in any large published trial. All HSRs occurred during the first dose. There was a strong relationship between prior allergy history and chance of HSR.
Conclusion: At the sites in neighboring NC and TN studied, HSR was far more common than reported in national studies. History of prior allergy is a strong predictor of HSR. Further investigation of more specific predictors of HSR in the US middle south region is warranted, and patients being treated with cetuximab in this area should be observed particularly closely during their first infusion.