Maier S, Chung CH, Morse M, Platts-Mills T, Townes L, et al.
Cancer medicine •
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.
Journal of oncology pharmacy practice : official publication of the International Society of Oncology Pharmacy Practitioners •
Previous research has indicated a high incidence of cetuximab hypersensitivity reactions in the southern US. This study documents the incidence of hypersensitivity reactions in North Carolina, and explores whether factors such as patient demographics, allergy history, premedications, and cancer type are potential predictors for cetuximab reactions. This retrospective chart review consisted of 72 consecutively treated patients from Duke University's Morris Oncology treatment center between September 2005 and August 2007. Data regarding stage of malignancy, premedications, and hypersensitivity reactions were collected from electronic databases. The number and type of reactions were characterized. Patients with and without hypersensitivity reactions were compared using bivariate statistics and multivariate logistic regression. Of the 72 patients, 21 (29%) experienced hypersensitivity reactions. The majority of reactions (62%) were grades III or IV. Of the 21 patients having a reaction, 9 (43%) were sent to the emergency room and 5 (24%) had an overnight hospitalization. Three hospitalized patients were admitted to the intensive care unit. Both male gender (p = 0.039) and head/neck cancer (p = 0.014) were related to an increased likelihood of hypersensitivity reaction in bivariate analyses. In multivariate analyses, controlling for demographics, allergy history, premedications, and cancer type/stage, only type of cancer was predictive of hypersensitivity reaction (colon vs head/neck OR = 0.177; 95% CI 0.036-0.858). This study confirms a high rate of cetuximab hypersensitivity reactions in a southern region of the US. Patients with head/neck cancers were significantly more likely to have hypersensitivity reactions than patients with colon cancers.
Chung CH, Mirakhur B, Chan E, Le QT, Berlin J, et al.
The New England journal of medicine •
Cetuximab, a chimeric mouse-human IgG1 monoclonal antibody against the epidermal growth factor receptor, is approved for use in colorectal cancer and squamous-cell carcinoma of the head and neck. A high prevalence of hypersensitivity reactions to cetuximab has been reported in some areas of the United States. We analyzed serum samples from four groups of subjects for IgE antibodies against cetuximab: pretreatment samples from 76 case subjects who had been treated with cetuximab at multiple centers, predominantly in Tennessee, Arkansas, and North Carolina; samples from 72 control subjects in Tennessee; samples from 49 control subjects with cancer in northern California; and samples from 341 female control subjects in Boston. Among 76 cetuximab-treated subjects, 25 had a hypersensitivity reaction to the drug. IgE antibodies against cetuximab were found in pretreatment samples from 17 of these subjects; only 1 of 51 subjects who did not have a hypersensitivity reaction had such antibodies (P<0.001). IgE antibodies against cetuximab were found in 15 of 72 samples (20.8%) from control subjects in Tennessee, in 3 of 49 samples (6.1%) from northern California, and in 2 of 341 samples (0.6%) from Boston. The IgE antibodies were shown to be specific for an oligosaccharide, galactose-alpha-1,3-galactose, which is present on the Fab portion of the cetuximab heavy chain. In most subjects who had a hypersensitivity reaction to cetuximab, IgE antibodies against cetuximab were present in serum before therapy. The antibodies were specific for galactose-alpha-1,3-galactose.
This phase II trial assessed the activity and tolerability of cetuximab (C225, Erbitux) in combination with carboplatin in patients with relapsed platinum-sensitive ovarian or primary peritoneal carcinoma. Patients were to receive combination therapy with cetuximab (initial dose of 400 mg/m2 intravenously on cycle 1, day 1, followed by weekly infusions of 250 mg/m2) and carboplatin (AUC of 6 on day 1 and every 3 weeks). The primary objectives of this trial were to estimate the anti-tumor activity and adverse events of this combination therapy. Immunohistochemical expression of EGFR was evaluated in tumor specimens from patients enrolled in this trial. Of the 29 patients, 28 (97%) were eligible and evaluable for analysis of the efficacy and toxicity of cetuximab administered in combination with carboplatin. Of the evaluable entries, 26 had EGFR-positive tumors and the response rate in this group of patients was as follows: 9 demonstrated an objective response (3 CR; 6 PR) and 8 had stable disease. The response rate did not meet criteria for opening a second stage of accrual. The median time to progression was 9.4+ months (range: .9-22.2+). The most commonly observed adverse events were dermatologic toxicity (grade 3 in 32%), thrombocytopenia (grade 3 in 14%), and hypersensitivity reactions (grade 3 and 4 in 18%). Cetuximab administered in combination with carboplatin had modest activity in screened patients with EGFR-positive, relapsed platinum-sensitive ovarian or primary peritoneal carcinoma. Cetuximab was associated with an acneiform rash in a majority of patients and occasional serious hypersensitivity reactions.
Gal alpha 1,3 Gal is thought to be the major antigenic epitope present on pig tissues to which XNAs bind. Removal of antibodies directed against that structure may be critical to the success of pig to human xeno-transplantation. As a first step toward the development of ligands capable of removing XNAs, we have used a phage-displayed peptide library to identify a six-amino-acid peptide that binds to the lectin GS-1-B4 (which binds the carbohydrate Gal alpha 1,3 Gal). This peptide blocks the binding of GS-1-B4 to pig aortic endothelial cells. The carbohydrate Gal alpha 1,3 Gal competes with the binding of GS-1-B4 to the peptide, suggesting that they may bind the same site. Using a RBC agglutination assay, we show that this peptide inhibits the agglutination of pig RBCs by heat-inactivated human serum at concentrations similar to that of Gal alpha 1,3 Gal.