h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms.

The prognosis of patients with advanced head and neck cancer remain dismal. For this tumor type, elevated levels of EGFR are associated with a shorter disease free survival and time to treatment failure, reflecting a more aggressive phenotype. Nimotuzumab is a humanized monoclonal antibody that recognizes domain III of the extracellular region of the EGFR, within an area that overlaps with both the surface patch recognized by cetuximab and the binding site for EGF. In order to assess the efficacy of nimotuzumab in combination with radiotherapy, a controlled, double blind, randomized clinical trial was conducted in 106 advanced squamous cell carcinoma of the head and neck patients, mostly, unfit for chemoradiotherapy. Control patients received a placebo and radiotherapy. Treatment was safe and the most frequent adverse events consisted on grade I or II asthenia, fever, headache and chills. No skin rash was detected. A significant complete response rate improvement was found in the group of patients treated with nimotuzumab as compared to the placebo. In the intent to treat analysis, a trend towards survival benefit for nimotuzumab treated subjects was found. The survival benefit became significant when applying the Harrington-Fleming test, a weighted log-rank that underscores the detection of differences deferred on time. In addition, a preliminary biomarker investigation showed a significant survival improvement for nimotuzumab treated patients as compared to controls for subjects with EGFR positive tumors. All patients showed a quality of life improvement and a reduction of the general and specific symptoms of the disease.

Epidermal growth factor receptor (EGFR) overexpression has been detected in many tumors of epithelial origin, and it is often associated with tumor growth advantages and poor prognosis. h-R3 is a genetically engineered humanized antibody (mAb) that recognizes an epitope located in the extracellular domain of human EGFR. The antibody exhibited potent in vitro and in vivo antitumor effect on EGFR overexpressing cell lines. To study safety, pharmacokinetics, and biodistribution, 12 patients with advanced epithelial-derived tumors received single intravenous infusion of h-R3 at four dose levels. Safety evaluation was made according to World Health Organization toxicity criteria. For biodistribution, 3 mg of the total dose were labeled with Technetium and then pooled with the rest of the dose. Anterior and posterior whole-body images were acquired using a gamma camera. Blood samples were taken for pharmacokinetics, antiidiotypic response, and for soluble EGFR detection. After hR3 administration, no evidence of severe toxicity was observed. Secondary reactions were mild and moderate and mainly consisted of tremors, fever, and vomiting. No anaphylactic or skin reactions were detected. Qualitative analysis of whole-body images showed that the liver had the highest mAb uptake. Pharmacokinetic analysis revealed that elimination half-lives and the AUC increased linearly with dose, while total body clearance decreased when increasing doses of h-R3. No relation between shed EGFR and mAb clearance was found. No antiidiotypic response against h-R3 was detected. Several phase II trials are now underway to evaluate the efficacy of h-R3 in the treatment of advanced cancer patients.

The poor prognosis of patients with high-grade glioma has led to the search for new therapeutic strategies. More than half of these tumors overexpress Epidermal Growth factor Receptor (EGFR). h-R3 is a humanized monoclonal antibody that recognize the EGFR external domain with high affinity, inhibiting tyrosine kinase activation. In order to evaluate safety, immunogenicity and preliminary efficacy of h-R3 in newly diagnosed high-grade glioma patients, we conducted a Phase I/II trial. Patients received six weekly infusions of h-R3 at the dose of 200 mg in combination with external beam radiotherapy. Twenty-nine patients (mean age, 45 years and median KPS 80) were entered into the study. Tumor types were: glioblastoma (GB) (16 patients), anaplastic astrocytoma (AA) (12 patients) and anaplastic oligodendroglioma (AO) (1 patient). All patients underwent debulking surgery or biopsy before entering the trial. The antibody was very well tolerated. No evidences of grade 3/4 adverse events were detected. None of the patients developed acneiform rash or allergic reactions. One patient developed a positive anti-idiotypic response. Objective response-rate was 37.9% (17.2% complete response, 20.7% partial response) while stable disease occurred in 41.4% of the patients. With a median follow up time of 29 months, the median survival is 22.17 months for all subjects. Median survival time (MST) is 17.47 months for GB, whereas MST is not reached for AA patients.