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Background: Resistance to imatinib mesylate can occur in chronic myelogenous leukemia (CML). Preclinical in vitro studies have shown that nilotinib (AMN107), a new BCR-ABL tyrosine kinase inhibitor, is more potent than imatinib against CML cells by a factor of 20 to 50.Methods: In a phase 1 dose-escalation study, we assigned 119 patients with imatinib-resistant CML or acute lymphoblastic leukemia (ALL) to receive nilotinib orally at doses of 50 mg, 100 mg, 200 mg, 400 mg, 600 mg, 800 mg, and 1200 mg once daily and at 400 mg and 600 mg twice daily.Results: Common adverse events were myelosuppression, transient indirect hyperbilirubinemia, and rashes. Of 33 patients with the blastic phase of disease, 13 had a hematologic response and 9 had a cytogenetic response; of 46 patients with the accelerated phase, 33 had a hematologic response and 22 had a cytogenetic response; 11 of 12 patients with the chronic phase had a complete hematologic remission.Conclusions: Nilotinib has a relatively favorable safety profile and is active in imatinib-resistant CML. (ClinicalTrials.gov number, NCT00109707 [ClinicalTrials.gov].). [ABSTRACT FROM AUTHOR]

Purpose: In this first-in-human study of AEE788, a tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR), HER-2, and VEGFR-2, a comprehensive pharmacodynamic program was implemented in addition to the evaluation of safety, pharmacokinetics, and preliminary efficacy of AEE788 in cancer patients., Experimental Design: Patients with advanced, solid tumors received escalating doses of oral AEE788 once daily. Primary endpoints were to determine dose-limiting toxicities (DLTs) and maximum-tolerated dose (MTD). A nonlinear model (Emax model) was used to describe the relationship between AEE788 exposure and target-pathway modulation in skin and tumor tissues., Results: Overall, 111 patients were treated (25 to 550 mg/day). DLTs included rash and diarrhea; MTD was 450 mg/day. Effects on biomarkers correlated to serum AEE788 concentrations. The concentration at 50% inhibition (IC(50)) for EGFR in skin (0.033 μmol/L) and tumor (0.0125 μmol/L) were similar to IC(50) in vitro suggesting skin may be surrogate tissue for estimating tumor EGFR inhibition. No inhibition of p-MAPK and Ki67 was observed in skin vessels at ≤ MTD. Hence, AEE788 inhibited EGFR, but not VEGFR, at doses ≤ MTD. A total of 16 of 96 evaluable patients showed a >10% shrinkage of tumor size; one partial response was observed., Conclusion: Our pharmacodynamic-based study showed effective inhibition of EGFR, but not of VEGFR at tolerable AEE788 doses. Emax modeling integrated with biomarker data effectively guided real-time decision making in the early development of AEE788. Despite clinical activity, target inhibition of only EGFR led to discontinuation of further AEE788 development., (©2012 AACR.)

Purpose: Vascular endothelial growth factor receptor (VEGFR) and epidermal growth factor receptor (EGFR) play a significant role in glioblastoma angiogenesis and proliferation, making tyrosine kinase (TK) receptors logical targets for treatment. We evaluated AEE788, a reversible TK inhibitor that inhibits EGFR and VEGFR, in recurrent glioblastoma patients., Methods: In this dose-escalation, phase I study, patients with recurrent glioblastoma received AEE788 once daily in 28-day cycles in stratified subgroups: those receiving (1) non-enzyme-inducing anticonvulsants drugs or no anticonvulsants (Group A) and (2) enzyme-inducing anticonvulsant drugs (Group B). A dose-expansion phase stratified patients by surgical eligibility. Primary objectives were to determine dose-limiting toxicity (DLT) and maximum tolerated dose; secondary objectives included evaluating (1) safety/tolerability, (2) pharmacokinetics, and (3) preliminary antitumor activity., Results: Sixty-four glioblastoma patients were enrolled. Two Group A patients experienced DLTs (proteinuria and stomatitis) at 550 mg; 550 mg was, therefore, the highest dose evaluated and dose limiting. One Group B patient receiving 800 mg experienced a DLT (diarrhea). The initially recommended dose for dose-expansion phase for Group A was 400 mg; additional patients received 250 mg to assess the hepatotoxicity. Most frequently reported adverse events (AEs) included diarrhea and rash. Serious AEs, most commonly grade 3/4 liver function test elevations, were responsible for treatment discontinuation in 17% of patients. AEE788 concentrations were reduced by EIACD. The best overall response was stable disease (17%)., Conclusions: Continuous, once-daily AEE788 was associated with unacceptable toxicity and minimal activity for the treatment of recurrent glioblastoma. The study was, therefore, discontinued prematurely.

Sun et al. (2009) proposed an optimal two-stage randomized multinomial design that incorporates both response rate (RR) and early progression rate (EPR) in designing phase II oncology trials. However, determination of the design parameters in their approach requires evaluating huge numbers of combinations among possible values of design parameters, and thus requires highly intensive computation. In this paper we develop an efficient algorithm to identify the optimal two-stage randomized multinomial designs in phase II oncology clinical trials comparing a treatment arm to a control arm. The proposed algorithm substantially reduces the computation intensity via an approximation method. Some other techniques are also used to further improve its efficiency. Examples show that the proposed algorithm has more than a 90% reduction in computation time while having an acceptably low approximation error. This may enhance usage of the optimal two-stage multinomial design in clinical trials and also make it feasible to extend the design to more complicated scenarios.

For cytostatic cancer therapies, alternatives to traditional phase II endpoints are needed. Von Hoff (1998) proposed an intrapatient progression-free survival (PFS) ratio, the growth modulation index (GMI). Current practice in estimation of the GMI success rate is conservative and omits a measure of uncertainty. We investigated nonparametric and parametric methods to estimate the GMI success rate, including an approach using midranks for paired survival outcomes (Hudgens and Satten (2002)). Estimators were applied to a phase II GMI dataset (Bonetti et al. (2001)). From simulation studies, it was determined that a rank-based estimator had the most favorable statistical properties. Its point estimate bias was consistently within 1.5%; its bias and precision were robust over a range of effect and censoring scenarios. Using a proof of concept criterion of {P(GMI≥1)≥θ}, a simulation investigation found that a θ of 50%, for sample sizes between 20 and 30 patients, had type I error of ≤20% and a power to detect Von Hoff's 1.33 effect of ≥80%. When the amount of censoring was ≥20%, the midrank estimator had a minimum of 14% greater power over the simple percentage estimator for the GMI success rate. Future investigations reporting the GMI should consider adopting the midrank methodology., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Purpose: PTK787/ZK 222584 (PTK/ZK), an orally active inhibitor of vascular endothelial growth factor (VEGF) receptor tyrosine kinases, inhibits VEGF-mediated angiogenesis. The pharmacodynamic effects of PTK/ZK were evaluated by assessing changes in contrast-enhancement parameters of metastatic liver lesions using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in patients with advanced colorectal cancer treated in two ongoing, dose-escalating phase I studies., Patients and Methods: Twenty-six patients had DCE-MRI performed at baseline, day 2, and at the end of each 28-day cycle. Doses of oral PTK/ZK ranged from 50 to 2000 mg once daily. Tumor permeability and vascularity were assessed by calculating the bidirectional transfer constant (Ki). The percentage of baseline Ki (% of baseline Ki) at each time point was compared with pharmacokinetic and clinical end points., Results: A significant negative correlation exists between the % of baseline Ki and increase in PTK/ZK oral dose and plasma levels (P =.01 for oral dose; P =.0001 for area under the plasma concentration curve at day 2). Patients with a best response of stable disease had a significantly greater reduction in Ki at both day 2 and at the end of cycle 1 compared with progressors (mean difference in % of baseline Ki, 47%, P =.004%; and 51%, P =.006; respectively). The difference in % of baseline Ki remained statistically significant after adjusting for baseline WHO performance status., Conclusion: These findings should help to define a biologically active dose of PTK/ZK. These results suggest that DCE-MRI may be a useful biomarker for defining the pharmacological response and dose of angiogenesis inhibitors, such as PTK/ZK, for further clinical development.

Magnetic resonance imaging (MRI) was used to monitor cyclosporine therapy for chronic progressive multiple sclerosis in a multicenter clinical trial and an analysis was performed to determine whether there was a correlation between clinical changes and MRI changes. MRI was performed on 163 patients at the onset and completion of the 2-year study. Burden of disease (BOD, lesion load) was quantitated by a single observer using a computer program. Active lesions were also identified. The Expanded Disability Status Scale (EDSS) score was determined every 3 months MRI data did not show any effect of cyclosporine treatment on BOD progression (mean 24.5% increase/yr) or lesion activity. However, there was a statistically significant positive correlation between the baseline total BOD value and the baseline EDSS score (r = 0.221, p = 0.005) and a positive correlation between the percent changes in BOD from baseline to exit and EDSS score (r = 0.186, p = 0.018). The study supports the concepts that MRI is a useful technique in monitoring therapeutic trials and that MRI is a direct measure of pathology.

A prospective randomized trial in patients with previously untreated multiple myeloma was performed comparing carmustine (BCNU), cyclophosphamide, and prednisone (BCP) to melphalan (Alkeran) and prednisone (AP). Induction response rates, remission duration, and survival were similar with both regimens. Hematologic toxicity was greater with AP. Crossover studies in patients who relapsed did not illustrate any significant activity with either drug treatment program. Therefore, BCP can be utilized as initial therapy in myeloma because of comparable remission rates and less hematologic toxicity.

A 6-hour taped electrocardiogram recording was obtained prior to hospital discharge on 193 patients less than 66 years of age with a definite or probable myocardial infarction. All ventricular premature beats (VPBs) were identified on the 6-hour recording, and the various VPB characteristics were related to a complicated course (CC) defined as cardiac death or myocardial reinfarction within 4 months after hospital discharge. Only three univariate VPB characteristics (multiform pattern, bigeminal rhythm, and frequency greater than or equal to 20/hr) were significantly associated with a 4-month posthospital CC. By use of bivariate and multivariate combinations of these three VPB characteristics, a two-grade prognostic stratification system was derived: Grade I VPBs (CC = 8%) included patients with less than 20 VPB/hr but with neither multiform nor bigeminal beats: Grade II VPBs (CC = 31%, P less than 0.001) contained patients with greater than or equal to 20 VPBs/hr or with multiform or bigeminal beats or both. Patients with Grade II VPBs had more severe cardiac disease, but when patients were stratified by the clinical severity of their cardiac disease, Grade II VPBs identified patients with higher CC rates. The clinical significance of these findings together with a critical analysis of the prognostic stratification method are discussed.

One hundred sixty-seven patients with extensive well-differentiated and 120 patients with extensive poorly differentiated squamous cell carcinoma of the lung received chemotherapy as part of a randomized study by the Veterans Administration Lung Group. Chemotherapy was administration at random using one of the following four regimens: (1) cyclophosphamide alone; (2) cyclophosphamide plus 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU); (3) doxorubicin (adriamycin) plus cyclophosphamide; and (4) doxorubicin plus CCNU. With data on survival as the criteria for evaluation, it has been shown that combined chemotherapy using doxorubicin plus cyclophosphamide achieves greater median survival for patients with squamous cell cancer of the lung than single-drug chemotherapy using cyclophosphamide, under the conditions of this study; however, prolongation of life is still minimal, and better treatment is required. About 20 percent of the patients receiving any of the four regimens developed serious toxic effects from therapy with the drugs.