Severe first infusion reaction related to cetuximab in cancer patients in Arkansas

INTRODUCTION

Cetuximab, a chimeric monoclonal antibody, is a commonly used anticancer drug that prevents binding of epidermal growth factor to epidermal growth factor receptor. It has been widely used in a variety of cancers since its initial approval by the FDA in 2004. Despite its efficacy, it has met with some genuine concerns especially regarding the anaphylactoid reactions occurring after first infusions. Cetuximab-related first infusion reaction has been found to be much more prevalent in the Southeastern United States with several studies from the southern United States supporting it. The purpose of our study was to determine the rate of first infusion reaction in the state of Arkansas and the factors that could predispose to first infusion reaction.

METHODS AND RESULTS

We performed a retrospective chart review of consecutive patients who received cetuximab between January 2004 and December 2016 at the University of Arkansas for Medical Sciences. We included a total of 220 patients in our analysis out of which 32 (14.5%) developed cetuximab-related first infusion reaction. There was a statistically significant increased risk in males versus females (18.2% vs. 8.4%, P = 0.045) and trend toward significance for the difference between Caucasians and Blacks (16.5% vs. 7.1%, P = 0.054).

CONCLUSION

There is increased incidence of cetuximab-related first infusion reaction in Arkansas which is much higher than the national average but comparable to the incidence in other neighboring states in the Southeastern United States. This increased incidence tends to cluster in Caucasian males. Safer alternatives should be preferred for treatment of cancers particularly in the Southeastern United States whenever possible.

A retrospective analysis of cross-reacting cetuximab IgE antibody and its association with severe infusion reactions

Severe infusion reactions (SIRs) at rates of 5% or less are known side effects of biological agents, including mAbs such as cetuximab. There are currently no prospectively validated risk factors to aid physicians in identifying patients who may be at risk of experiencing an SIR following administration of any of these drugs. A retrospective analysis of 545 banked serum or plasma samples from cancer patients participating in clinical trials of cetuximab was designed to evaluate whether the presence of pretreatment IgE antibodies against cetuximab, as determined by a commercially available assay system, is associated with SIRs during the initial cetuximab infusion. Patients with a positive test indicating the presence of pretreatment antibodies had a higher risk of experiencing an SIR; however, at the prespecified cutoff utilized in this analysis, the test has a relatively low-positive predictive value (0.577 [0.369-0.766]) and a negative predictive value of 0.961 (0.912-0.987) in an unselected patient population. Data collected in this large retrospective validation study support prior observations of an association between the presence of pretreatment IgE antibodies cross-reactive with cetuximab and SIRs. Further analysis of the test's ability to predict patients at risk of an SIR would be required before this assay could be used reliably in this patient population.