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Purpose: Afatinib is an irreversible ErbB family blocker currently under evaluation in late-stage clinical trials. This study primarily assessed the cardiac safety, pharmacokinetics and antitumor activity of afatinib in cancer patients., Methods: In this multicenter, Phase II, open-label, single-arm trial, 60 patients with solid tumors who were expected to express epidermal growth factor receptor-1 and HER2 received oral afatinib 50 mg daily. QTcF intervals (QT interval corrected by the Fridericia formula) were evaluated based on electrocardiogram recordings time-matched with pharmacokinetic blood samples after single (Day 1) and continuous (Day 14; steady state) administration. Adverse events were classified according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE), version 3.0; antitumor activity was assessed using RECIST 1.0., Results: There was a nonsignificant decrease of 0.3 ms (90 % confidence interval -2.8, 2.3; N = 49) in the mean of the average time-matched QTcF interval from baseline to steady state. The maximum plasma concentration for afatinib was seen at median tmax 3 h after both single dose and at steady state. No relationship between afatinib plasma concentrations and time-matched QTcF, QT and heart rate change was found. The overall adverse event profile was consistent with the known safety profile of afatinib. One patient demonstrated a partial response (PR) and two patients unconfirmed PRs., Conclusions: Afatinib had no impact on cardiac repolarization, had a manageable safety profile and demonstrated antitumor activity in this uncontrolled study.

Purpose: AS1409 is a fusion protein comprising a humanized antibody BC1 linked to interleukin-12 (IL-12). It is designed to deliver IL-12 to tumor-associated vasculature using an antibody targeting the ED-B variant of fibronectin., Experimental Design: We conducted a phase 1 trial of weekly infusional AS1409 in renal carcinoma and malignant melanoma patients. Safety, efficacy, markers of IL-12-mediated immune response, and pharmacokinetics were evaluated., Results: A total of 11 melanoma and 2 renal cell carcinoma patients were treated. Doses of 15 and 25 μg/kg were studied. Most drug-related adverse events were grade 2 or less, and included pyrexia, fatigue, chills, headache, vomiting, and transient liver function abnormalities. Three dose limiting toxicities of grade 3 fatigue and transaminase elevation were seen at 25 μg/kg. IFN-γ and interferon-inducible protein-10 (IP-10) were elevated in all patients, indicating activation of cell-mediated immune response; this was attenuated at subsequent cycles. Antidrug antibody responses were seen in all patients, although bioassays indicate these do not neutralize AS1409 activity. Plasma half-life was 22 hours and not dose-dependent. Five patients received 6 cycles or more and a best response of at least stable disease was seen in 6 (46%) patients. Partial response was seen in a melanoma patient, and disease shrinkage associated with metabolic response was maintained beyond 12 months in another melanoma patient despite previous rapid progression., Conclusions: The maximum tolerated dose was established at 15 μg/kg weekly. AS1409 is well tolerated at this dose. Evidence of efficacy assessed by RECIST, functional imaging, and biomarker response warrants the planned further investigation using this dose and schedule in malignant melanoma.

Trastuzumab (Herceptin), a humanized IgG1 antibody raised against the human epidermal growth factor receptor 2 (HER2/neu), is the main antibody in clinical use against breast cancer. Pre-clinical evidence and clinical studies indicate that trastuzumab employs several anti-tumour mechanisms that most likely contribute to enhanced survival of patients with HER2/neu-positive breast carcinomas. New strategies are aimed at improving antibody-based therapeutics like trastuzumab, e.g. by enhancing antibody-mediated effector function mechanisms. Based on our previous findings that a chimaeric ovarian tumour antigen-specific IgE antibody showed greater efficacy in tumour cell killing, compared to the corresponding IgG1 antibody, we have produced an IgE homologue of trastuzumab. Trastuzumab IgE was engineered with the same light- and heavy-chain variable-regions as trastuzumab, but with an epsilon in place of the gamma-1 heavy-chain constant region. We describe the physical characterisation and ligand binding properties of the trastuzumab IgE and elucidate its potential anti-tumour activities in functional assays. Both trastuzumab and trastuzumab IgE can activate monocytic cells to kill tumour cells, but they operate by different mechanisms: trastuzumab functions in antibody-dependent cell-mediated phagocytosis (ADCP), whereas trastuzumab IgE functions in antibody-dependent cell-mediated cytotoxicity (ADCC). Trastuzumab IgE, incubated with mast cells and HER2/neu-expressing tumour cells, triggers mast cell degranulation, recruiting against cancer cells a potent immune response, characteristic of allergic reactions. Finally, in viability assays both antibodies mediate comparable levels of tumour cell growth arrest. These functional characteristics of trastuzumab IgE, some distinct from those of trastuzumab, indicate its potential to complement or improve upon the existing clinical benefits of trastuzumab.