Pharmacodynamic (phase 0) study using etaracizumab in advanced melanoma.

AlphaVbeta3 (alphavbeta3) is an important molecule for tumor-induced angiogenesis and is upregulated in metastatic melanoma (MM). We proposed to study the mechanism of action of etaracizumab, a monoclonal antibody targeting alphavbeta3, in MM. Patients with MM and biopsiable tumor were treated with etaracizumab in 3 dose cohorts starting from 8 mg/kg. Tumor saturation by etaracizumab using LM609 immunohistochemical staining of tumor sections was the primary endpoint. Subsequent dose cohorts were defined based on the tumor saturation by etaracizumab. Secondary end points were analysis of clinical benefit and changes from baseline of several tumor and peripheral blood biomarkers. Eighteen patients were enrolled at 3 dose levels. Etaracizumab showed better melanoma cell saturation at the 8mg/kg and 1 mg/kg dose compared with the 4 mg/kg dose and better vascular endothelial cell saturation at 8 mg/kg compared with lower dose groups. Etaracizumab demonstrated an acceptable safety profile. The optimal biologic dose out of those selected for investigation was 8 mg/kg. Patients treated at the highest dose may have had better clinical benefit secondary to suppression of the activated immediate downstream effector of alphavbeta3 signaling, FAK, in melanoma cells, but this alone did not ultimately affect melanoma cell proliferation or apoptosis. No apparent antiangiogenic or immunomodulatory effects of etaracizumab were noted.

A randomized phase 2 study of etaracizumab, a monoclonal antibody against integrin alpha(v)beta(3), + or - dacarbazine in patients with stage IV metastatic melanoma.

BACKGROUND: The alpha (v) beta (3) (alpha(v)beta(3)) integrin is involved in intracellular signaling regulating cell proliferation, migration, and differentiation and is important for tumor-induced angiogenesis. METHODS: This phase 2, randomized, open-label, 2-arm study was designed to capture safety data and evaluate the antitumor efficacy of etaracizumab (Abegrin), an IgG1 humanized monoclonal antibody against the alpha(v)beta(3) integrin, in patients with previously untreated metastatic melanoma. The objective was to evaluate whether etaracizumab + or - dacarbazine had sufficient clinical activity to warrant further study in a phase 3 clinical trial. RESULTS: One hundred twelve patients were randomized to receive etaracizumab alone (N = 57) or etaracizumab + dacarbazine (N = 55). Safety of etaracizumab + or - dacarbazine was acceptable with infusion-related, gastrointestinal, and metabolic reactions being the most common adverse events (AEs). The majority of AEs were grade 1 or 2 in severity in both study arms; most events were not considered serious, except for cardiovascular (myocardial infarction, atrial fibrillation) and thromboembolic events, which occurred in 3 and 5 patients, respectively. None of the patients in the etaracizumab-alone study arm and 12.7% of patients in the etaracizumab + dacarbazine study arm achieved an objective response. The median duration of objective response in the etaracizumab + dacarbazine study arm was 4.2 months. Stable disease rate, time to progression (TTP), and progression-free survival (PFS) appeared to be similar between the 2 treatment arms. Stable disease occurred in 45.6% of patients in the etaracizumab-alone study arm and 40.0% of patients in the etaracizumab + dacarbazine study arm. Median TTP and median PFS were both 1.8 months in the etaracizumab-alone study arm and 2.5 and 2.6 months in the etaracizumab + dacarbazine study arm, respectively. Median overall survival was 12.6 months in the etaracizumab-alone study arm and 9.4 months in the etaracizumab + dacarbazine study arm. CONCLUSIONS: The survival results in both treatment arms of this study were considered unlikely to result in clinically meaningful improvement over dacarbazine alone.

EBV-related lymphoproliferative disease complicating therapy with the anti-CD2 monoclonal antibody, siplizumab, in patients with T-cell malignancies.

PURPOSE: We report an increased incidence of EBV-induced B-cell lymphoproliferative disease (LPD) in patients treated with siplizumab, an anti-CD2 antibody. The development of EBV-LPD has been associated with the use of immunosuppressive agents used in solid organ, bone marrow, and stem cell transplantation and in certain congenital immunodeficiencies. EXPERIMENTAL DESIGN: We conducted a single-institution phase I dose-escalation trial of siplizumab, a humanized monoclonal antibody to CD2, in 29 patients with T-cell malignancies. RESULTS: Although initial responses were encouraging, 4 (13.7%) patients developed EBV-LPD and the trial was stopped. Reductions in CD4(+) and CD8(+) cell count numbers in response to therapy were seen in all patients, but in those patients developing EBV-LPD a significantly greater reduction in natural killer (NK) cell number and CD2 expression on T cells was seen. These findings highlight the importance of NK-cell depletion and CD2 expression in addition to T-cell depletion in the etiology of EBV-LPD. CONCLUSIONS: The emergence of EBV-LPD may be associated with the ability of siplizumab to deplete both T and NK cells without affecting B cells. Agents that deplete T- and NK-cell populations without affecting B cell number should be screened for this potentially serious adverse event.

Phase I and pharmacokinetic study of etaracizumab (Abegrin), a humanized monoclonal antibody against alphavbeta3 integrin receptor, in patients with advanced solid tumors.

This study assessed the safety, immunogenicity, and pharmacokinetics of etaracizumab, a monoclonal antibody directed against the alphavbeta3 integrin, in patients with advanced malignancies. Four cohorts of four patients received escalating dose of etaracizumab as a 30-min intravenous infusion, first as a single test dose, followed-up 2-5 weeks later by weekly doses. Sixteen patients with advanced solid tumors received a total of 309 cycles of etaracizumab at doses ranging 1-6 mg/kg. The mean number of weekly infusions was 19 (ranging 5-53). Frequently reported adverse events were grades 1-2 asthenia (15 patients) and infusion reactions (9 patients). At 1 mg/kg, one patient experienced grade 3 chills with the first infusion. Other grade 3 toxicities included reversible hyponatremia, hypophosphatemia and hyponatremia in one patient each at 1, 4 and 6 mg/kg, respectively. No patient experienced treatment delay/discontinuation due to an adverse event. The half-life of etaracizumab ranged 49-180 h with a nonlinear increase in terminal half-life with increasing doses. There was no objective response but five patients experienced a stable disease of >6-month duration. Etaracizumab was well-tolerated at doses up to 6 mg/kg with no evidence of immunogenicity. The safety profile of etaracizumab warrants further exploration in ongoing phase I/II trials.

Phase I trial of a monoclonal antibody specific for alphavbeta3 integrin (MEDI-522) in patients with advanced malignancies, including an assessment of effect on tumor perfusion.

At present, a variety of agents targeting tumor angiogenesis are under clinical investigation as new therapies for patients with cancer. Overexpression of the alpha(v)beta(3) integrin on tumor vasculature has been associated with an aggressive phenotype of several solid tumor types. Murine models have shown that antibodies targeting the alpha(v)beta(3) integrin can affect tumor vasculature and block tumor formation and metastasis. These findings suggest that antibodies directed at alpha(v)beta(3) could be investigated in the treatment of human malignancies. The current phase I dose escalation study evaluated the safety of MEDI-522, a monoclonal antibody specific for the alpha(v)beta(3) integrin, in patients with advanced malignancies. Twenty-five patients with a variety of metastatic solid tumors were treated with MEDI-522 on a weekly basis with doses ranging from 2 to 10 mg/kg/wk. Adverse events were assessed weekly; pharmacokinetic studies were done; and radiographic staging was done every 8 weeks. In addition, dynamic computed tomography imaging was done at baseline and at 8 weeks in patients with suitable target lesions amenable to analysis, to potentially identify the effect of MEDI-522 on tumor perfusion. Treatment was well tolerated, and a maximum tolerated dose was not identified by traditional dose-limiting toxicities. The major adverse events observed were grade 1 and 2 infusion-related reactions (fever, rigors, flushing, injection site reactions, and tachycardia), low-grade constitutional and gastrointestinal symptoms (fatigue, myalgias, and nausea), and asymptomatic hypophosphatemia. Dynamic computed tomography imaging suggested a possible effect on tumor perfusion with an increase in contrast mean transit time from baseline to the 8-week evaluation with increasing doses of MEDI-522. No complete or partial responses were observed. Three patients with metastatic renal cell cancer experienced prolonged stable disease (34 weeks, >1 and >2 years) on treatment. With this weekly schedule of administration, and in the doses studied, MEDI-522 seems to be without significant toxicity, may have effects on tumor perfusion, and may have clinical activity in renal cell cancer. These findings suggest the MEDI-522 could be further investigated as an antiangiogenic agent for the treatment of cancer.

Alpha-1-acid glycoprotein as an independent predictor for treatment effects and a prognostic factor of survival in patients with non-small cell lung cancer treated with docetaxel.

PURPOSE: To identify predictors of treatment outcome and survival in patients with non-small cell lung cancer (NSCLC) treated with docetaxel. EXPERIMENTAL DESIGN: The data were collected from 180 NSCLC patients enrolled in six docetaxel Phase II studies at a dose of 100 mg/m(2). Clinical end points for this study were safety reported as the first course adverse events requiring dose reduction, and efficacy was measured by response rate and survival. The independent variables included docetaxel dose, individual estimates of clearance, area under the plasma concentration time curve, extent of previous treatment, and covariables related to the patient's demographics, extent of disease, and performance status. The data were analyzed using a logistic regression model for response and severe adverse events and a Cox multivariate regression model for survival. RESULTS: Docetaxel exposure as measured by the area under the plasma concentration time curve was the only significant predictor (P < 0.0001) of severe toxicity during the first course of therapy. Baseline alpha1-acid glycoprotein (AAG) was the only significant predictor of response with an odds ratio of 0.44 for changes in AAG from 1.11 to 1.85 grams/liter (P = 0.0039). Cumulative dose, AAG, and extent of disease were independent predictors of survival (P < 0.005). The median survival varied from 15.6 months for patients with a low AAG (AAG < or = 1.11 grams/liter) to 5.5 months for patients with a high AAG (AAG >/= 1.85 grams/liter). CONCLUSION: AAG appears to be an independent predictor of response and a major objective prognostic factor of survival in patients with NSCLC treated with docetaxel chemotherapy.