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.
Argiris A, Feinstein TM, Wang L, Yang T, Agrawal S, et al.
Investigational new drugs •
Combined inhibition of epidermal growth factor receptor (EGFR) and Src family kinases (SFK) may lead to improved therapeutic effects. We evaluated the combination of dasatinib, an inhibitor of SFK and other kinases, and cetuximab, an anti-EGFR monoclonal antibody. Patients with advanced solid malignancies received cetuximab intravenously on a standard weekly schedule and dasatinib orally, once daily at 3 dose levels: (1) 100 mg, (2) 150 mg, (3) 200 mg. Pharmacokinetic and pharmacodynamic studies of dasatinib were performed prior to starting cetuximab and following 14 days of treatment. Twenty-five patients (3 dose level 1; 19 dose level 2; 3 dose level 3) were initially treated. Three patients developed dose-limiting toxicities: 1 at dose level 2 (headache) and 2 at dose level 3 (headache, nausea). Grade 3-4 toxicities in more than 2 patients included: dyspnea (4), vomiting (4), nausea (3), hypersensitivity reactions (3), headache (3) and anemia (3). Twenty-one patients developed headache (8 grade 1; 10 grade 2), which occurred after the loading of cetuximab and lasted 1-3 days. Six additional patients were treated with dasatinib starting 3 days after the loading dose of cetuximab; none developed headache after dasatinib. Dasatinib pharmacokinetics and a transient decrease in SFK PY416 levels in peripheral blood mononuclear cells were not altered by cetuximab. Patients with higher plasma TGF-alpha levels had worse progression-free survival. Dasatinib 150 mg once daily plus weekly cetuximab is recommended for phase II studies. Early-onset headache was ameliorated by starting dasatinib after cetuximab.
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.
Journal of clinical oncology : official journal of the American Society of Clinical Oncology •
To evaluate the antitumor activity and toxicity of single-agent cetuximab in patients with chemotherapy-refractory colorectal cancer whose tumors express the epidermal growth factor receptor. Phase II, open-label clinical trial. Patients were required to have EGFr expression demonstrated on formalin-fixed paraffin-embedded tumor tissue by immunohistochemical staining before study participation. Patients were required to have received irinotecan, either alone or in a combination regimen, and to have demonstrated clinical failure on this regimen before study entry. Cetuximab was administered weekly by intravenous infusion. The first dose of 400 mg/m(2) was given during the course of 2 hours. Subsequent weekly treatments were given at a dose of 250 mg/m(2) during the course of 1 hour. Fifty-seven eligible patients were treated. All were assessable for toxicity and response. The most commonly encountered grade 3 to 4 adverse events, regardless of relationship to study drug, were an acne-like skin rash, predominantly on the face and upper torso (86% with any grade; 18% with grade 3), and a composite of asthenia, fatigue, malaise, or lethargy (56% with any grade, 9% with grade 3). Two patients (3.5%) experienced grade 3 allergic reactions requiring discontinuation of study treatment. A third patient experienced a grade 3 allergic reaction that resolved, and the patient continued on the study. Neither diarrhea nor neutropenia were dose limiting in any of the 57 patients treated. Five patients (9%; 95% CI, 3% to 19%) achieved a partial response. Twenty-one additional patients had stable disease or minor responses. The median survival in these previously treated patients with chemotherapy-refractory colorectal cancer is 6.4 months. Cetuximab on this once-weekly schedule has modest activity and is well-tolerated as a single agent in patients with chemotherapy-refractory colorectal cancer whose tumors express the epidermal growth factor receptor. Further studies of cetuximab will evaluate the use of cetuximab in conjunction with first-line and adjuvant treatments for this disease.