962 resultados para Étude de phase I
Resumo:
The treatment of patients with recurrent glioblastoma remains a major oncologic problem, with median survival after progression of 7-9 months. To determine the maximum tolerated dose and dose-limiting toxicity (DLT), the combination of dasatinib and cyclonexyl-chloroethyl-nitrosourea (CCNU) was investigated in this setting. The study was designed as multicenter, randomized phase II trial, preceded by a lead-in safety phase. The safety component reported here, which also investigated pharmacokinetics and preliminary clinical activity, required expansion and is therefore considered a phase I part to establish a recommended dosing regimen of the combination of CCNU (90-110 mg/m(2)) and dasatinib (100-200 mg daily). Overall, 28 patients were screened, and 26 patients were enrolled. Five dose levels were explored. DLTs, mainly myelosuppression, occurred in 10 patients. Grade 3 or 4 neutropenia was recorded in 7 patients (26.9%) and thrombocytopenia in 11 patients (42.3%). No significant effect of CCNU coadministration on dasatinib pharmacokinetics was found. Median progression-free survival (PFS) was 1.35 months (95% confidence interval: 1.2-1.4) and 6-month PFS was 7.7%. In this phase I study of recurrent glioblastoma patients, the combination of CCNU and dasatinib showed significant hematological toxicities and led to suboptimal exposure to both agents.
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BACKGROUND: A phase I dose-escalation trial of transarterial chemoembolisation (TACE) with idarubicin-loaded beads was performed in cirrhotic patients with hepatocellular carcinoma (HCC). AIM: To estimate the maximum-tolerated dose (MTD) and to assess safety, efficacy, pharmacokinetics and quality of life. METHODS: Patients received a single TACE session with injection of 2 mL drug-eluting beads (DEBs; DC Bead 300-500 μm) loaded with idarubicin. The idarubicin dose was escalated according to a modified continuous reassessment method. MTD was defined as the dose level closest to that causing dose-limiting toxicity (DLT) in 20% of patients. RESULTS: Twenty-one patients were enrolled, including nine patients at 5 mg, six patients at 10 mg, and six patients at 15 mg. One patient at each dose level experienced DLT (acute myocardial infarction, hyperbilirubinaemia and elevated aspartate aminotransferase (AST) at 5-, 10- and 15-mg, respectively). The calculated MTD of idarubicin was 10 mg. The most frequent grade ≥3 adverse events were pain, elevated AST, elevated γ-glutamyltranspeptidase and thrombocytopenia. At 2 months, the objective response rate was 52% (complete response, 28%, and partial response, 24%) by modified Response Evaluation Criteria in Solid Tumours. The median time to progression was 12.1 months (95% CI 7.4 months - not reached); the median overall survival was 24.5 months (95% CI 14.7 months - not reached). Pharmacokinetic analysis demonstrated the ability of DEBs to release idarubicin slowly. CONCLUSIONS: Using drug-eluting beads, the maximum-tolerated dose of idarubicin was 10 mg per TACE session. Encouraging responses and median time to progression were observed. Further clinical investigations are warranted (NCT01040559).
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Pavement marking technology is a continually evolving subject. There are numerous types of materials used in the field today, including (but not limited to) paint, epoxy, tape, and thermoplastic. Each material has its own set of unique characteristics related to durability, retroreflectivity, installation cost, and life-cycle cost. The Iowa Highway Research Board was interested in investigating the possibility of developing an ongoing program to evaluate the various products used in pavement marking. This potential program would maintain a database of performance and cost information to assist state and local agencies in determining which materials and placement methods are most appropriate for their use. The Center for Transportation Research and Education at Iowa State University has completed Phase I of this research: to identify the current practice and experiences from around the United States to recommend a further course of action for the State of Iowa. There has been a significant amount of research completed in the last several years. Research from Michigan, Pennsylvania, South Dakota, Ohio, and Alaska all had some common findings: white markings are more retroreflective than yellow markings; paint is by-and-large the least expensive material; paint tends to degrade faster than other materials; thermoplastic and tapes had higher retroreflective characteristics. Perhaps the most significant program going on in the area of pavement markings is the National Transportation Product Evaluation Program (NTPEP). This is an ongoing research program jointly conducted by the American Association of State Highway and Transportation Officials and its member states. Field and lab tests on numerous types of pavement marking materials are being conducted at sites representing four climatological areas. These results are published periodically for use by any jurisdiction interested in pavement marking materials performance. At this time, it is recommended that the State of Iowa not embark on a test deck evaluation program. Instead, close attention should be paid to the ongoing evaluations of the NTPEP program. Materials that fare well on the NTPEP test de cks should be considered for further field studies in Iowa.
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The project described herein has led to a convenient, computer-based expert system for identifying and evaluating potentially effective erosion- and sedimentation-control measures for use in roadway construction throughout Iowa and elsewhere in the Midwest. The expert system is intended to be an accessible and efficient practical resource to aid state, county, and municipal engineers in the selection of the best management practices for preventing unwanted erosion and sedimentation at roadway construction sites, during and after construction.
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PURPOSE: As no curative treatment for advanced pancreatic and biliary cancer with malignant ascites exists, new modalities possibly improving the response to available chemotherapies must be explored. This phase I study assesses the feasibility, tolerability and pharmacokinetics of a regional treatment of gemcitabine administered in escalating doses by the stop-flow approach to patients with advanced abdominal malignancies (adenocarcinoma of the pancreas, n = 8, and cholangiocarcinoma of the liver, n = 1). EXPERIMENTAL DESIGN: Gemcitabine at 500, 750 and 1,125 mg/m(2) was administered to three patients at each dose level by loco-regional chemotherapy, using hypoxic abdominal stop-flow perfusion. This was achieved by an aorto-caval occlusion by balloon catheters connected to an extracorporeal circuit. Gemcitabine and its main metabolite 2',2'-difluorodeoxyuridine (dFdU) concentrations were measured by high performance liquid chromatography with UV detection in the extracorporeal circuit during the 20 min of stop-flow perfusion, and in peripheral plasma for 420 min. Blood gases were monitored during the stop-flow perfusion and hypoxia was considered stringent if two of the following endpoints were met: pH </= 7.2, pO(2) nadir ratio </=0.70 or pCO(2) peak ratio >/=1.35. The tolerability of this procedure was also assessed. RESULTS: Stringent hypoxia was achieved in four patients. Very high levels of gemcitabine were rapidly reached in the extracorporeal circuit during the 20 min of stop-flow perfusion, with C (max) levels in the abdominal circuit of 246 (+/-37%), 2,039 (+/-77%) and 4,780 (+/-7.3%) mug/ml for the three dose levels 500, 750 and 1,125 mg/m(2), respectively. These C (max) were between 13 (+/-51%) and 290 (+/-12%) times higher than those measured in the peripheral plasma. Similarly, the abdominal exposure to gemcitabine, calculated as AUC(t0-20), was between 5.5 (+/-43%) and 200 (+/-66%)-fold higher than the systemic exposure. Loco-regional exposure to gemcitabine was statistically higher in presence of stringent hypoxia (P < 0.01 for C (max) and AUC(t0-20), both normalised to the gemcitabine dose). Toxicities were acceptable considering the complexity of the procedure and were mostly hepatic; it was not possible to differentiate the respective contributions of systemic and regional exposures. A significant correlation (P < 0.05) was found between systemic C (max) of gemcitabine and the nadir of both leucocytes and neutrophils. CONCLUSIONS: Regional exposure to gemcitabine-the current standard drug for advanced adenocarcinoma of the pancreas-can be markedly enhanced using an optimised hypoxic stop-flow perfusion technique, with acceptable toxicities up to a dose of 1,125 mg/m(2). However, the activity of gemcitabine under hypoxic conditions is not as firmly established as that of other drugs such as mitomycin C, melphalan or tirapazamine. Further studies of this investigational modality, but with bioreductive drugs, are therefore warranted first to evaluate the tolerance in a phase I study and later on to assess whether it does improve the response to chemotherapy.
Resumo:
Phase I was initiated as a result of internal Iowa Department of Transportation (Iowa DOT) studies that raised concerns about the quality of embankments being constructed. Some large embankments have recently developed slope stability problems. In addition, pavement roughness has been noted shortly after roads were opened to traffic. This raised the question as to whether the current Iowa DOT embankment construction specifications are adequate. The primary objective of Phase I was to evaluate the quality of embankments being constructed under the current Iowa DOT specifications. The project was initiated in May 1997 with a tour of several embankment projects being constructed around the state. At each of these projects the resident construction engineer, field inspector, and contractor were interviewed with respect to their opinion of the current specifications. From construction observations and discussion during these visits it became obvious that there were problems with the current embankment construction specifications. Six embankment projects were selected for in-depth analysis and to represent the full range of soil types being used across the state. The results of Phase I field and laboratory construction testing and observations and post construction testing are presented in this report. Overall evaluation of the results of Phase I indicate that Iowa is not consistently obtaining a quality embankment constructed under the current Iowa DOT specifications. Based on these results, recommendations are made for Phase II to evaluate alternative specifications and develop rapid field methods for compaction control and soil identification.
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The aim of this Phase I/IIa double-blind controlled trial was to test the efficacy of the sporozoite-based malaria vaccine PfCS 282-383 (PfCS102) to protect against Plasmodium falciparum parasitaemia. 16 volunteers were randomized to receive twice 30 μg of PfCS102 formulated in Montanide ISA 720 or ISA 720 alone (control). Two weeks after 2nd immunization, volunteers were challenged using 5 infected mosquitoes. All vaccinees developed antibodies against PfCS102 versus none control. 8/8 vaccinees and 6/6 controls challenged developed malaria parasitaemia. The duration from infection to onset of patent parasitaemia was similar in both groups (214 h in vaccinees and 216 in controls). PfCS102 is safe and immunogenic but provides no protection against artificial challenge in its current formulation.
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This article describes the application of a recently developed general unknown screening (GUS) strategy based on LC coupled to a hybrid linear IT-triple quadrupole mass spectrometer (LC-MS/MS-LIT) for the simultaneous detection and identification of drug metabolites following in vitro incubation with human liver microsomes. The histamine H1 receptor antagonist loratadine was chosen as a model compound to demonstrate the interest of such approach, because of its previously described complex and extensive metabolism. Detection and mass spectral characterization were based on data-dependent acquisition, switching between a survey scan acquired in the ion-trapping Q3 scan mode with dynamic subtraction of background noise, and a dependent scan in the ion-trapping product ion scan mode of automatically selected parent ions. In addition, the MS(3) mode was used in a second step to confirm the structure of a few fragment ions. The sensitivity of the ion-trapping modes combined with the selectivity of the triple quadrupole modes allowed, with only one injection, the detection and identification of 17 phase I metabolites of loratadine. The GUS procedure used in this study may be applicable as a generic technique for the characterization of drug metabolites after in vitro incubation, as well as probably in vivo experiments.
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BACKGROUND: Brain metastases (BMs) pose a clinical challenge in breast cancer (BC). Lapatinib or temozolomide showed activity in BM. Our study assessed the combination of both drugs as treatment for patients with HER2-positive BC and BM. METHODS: Eighteen patients were enrolled, with sixteen of them having recurrent or progressive BM. Any type of previous therapy was allowed, and disease was assessed by gadolinium (Gd)-enhanced magnetic resonance imaging (MRI). The primary end points were the evaluation of the dose-limiting toxicities (DLTs) and the determination of the maximum-tolerated dose (MTD). The secondary end points included objective response rate, clinical benefit and duration of response. RESULTS: The lapatinib-temozolomide regimen showed a favorable toxicity profile because the MTD could not be reached. The most common adverse events (AEs) were fatigue, diarrhea and constipation. Disease stabilization was achieved in 10 out of 15 assessable patients. The estimated median survival time for the 16 patients with BM reached 10.94 months (95% CI: 1.09-20.79), whereas the median progression-free survival time was 2.60 months [95% confidence interval (CI): 1.82-3.37]. CONCLUSIONS: The lapatinib-temozolomide combination is well tolerated. Preliminary evidence of clinical activity was observed in a heavily pretreated population, as indicated by the volumetric reductions occurring in brain lesions.
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The first phase of a two-phase research project was conducted to develop guidelines for Iowa transportation officials on the use of thin maintenance surfaces (TMS) for asphaltic concrete and bituminous roads. Thin maintenance surfaces are seal coats (chip seals), slurry seals, and micro-surfacing. Interim guidelines were developed to provide guidance on which roads are good candidates for TMS, when TMS should be placed, and what type of thin maintenance surface should be selected. The guidelines were developed specifically for Iowa aggregates, weather, traffic conditions, road user expectations, and transportation official expectations. In addition to interim guidelines, this report presents recommendations for phase-two research. It is recommended that test section monitoring continue and that further investigations be conducted regarding thin maintenance surface aggregate, additional test sections, placed, and a design method adopted for seal coats.
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Background: Two or three DNA primes have been used in previous smaller clinical trials, but the number required for optimal priming of viral vectors has never been assessed in adequately powered clinical trials. The EV03/ANRS Vac20 phase I/II trial investigated this issue using the DNA prime/poxvirus NYVAC boost combination, both expressing a common HIV-1 clade C immunogen consisting of Env and Gag-Pol-Nef polypeptide. Methods: 147 healthy volunteers were randomly allocated through 8 European centres to either 3xDNA plus 1xNYVAC (weeks 0, 4, 8 plus 24; n¼74) or to 2xDNA plus 2xNYVAC (weeks 0, 4 plus 20, 24; n¼73), stratified by geographical region and sex. T cell responses were quantified using the interferon g Elispot assay and 8 peptide pools; samples from weeks 0, 26 and 28 (time points for primary immunogenicity endpoint), 48 and 72 were considered for this analysis. Results: 140 of 147 participants were evaluable at weeks 26 and/ or 28. 64/70 (91%) in the 3xDNA arm compared to 56/70 (80%) in the 2xDNA arm developed a T cell response (P¼0.053). 26 (37%) participants of the 3xDNA arm developed a broader T cell response (Env plus at least to one of the Gag, Pol, Nef peptide pools) versus 15 (22%) in the 2xDNA arm (P¼0.047). At week 26, the overall magnitude of responses was also higher in the 3xDNA than in the 2xDNA arm (similar at week 28), with a median of 545 versus 328 SFUs/106 cells at week 26 (P<0.001). Preliminary overall evaluation showed that participants still developed T-cell response at weeks 48 (78%, n¼67) and 72 (70%, n¼66). Conclusion: This large clinical trial demonstrates that optimal priming of poxvirus-based vaccine regimens requires 3 DNA regimens and further confirms that the DNA/NYVAC prime boost vaccine combination is highly immunogenic and induced durable T-cell responses.
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This report presents the results of research on the influence of trace compounds from rock salt deicers on portland cement mortar and concrete. An evaluation of the deicers in stock throughout the state showed that about ninety-five percent contained enough sulfate to cause accelerated deterioration of concrete. Of the impurities found in rock salts, sulfate compounds of calcium and magnesium were found to be equally deleterious. Magnesium chloride was found to be innocuous. Introduction of fly ash eliminated the damage to portland cement mortar caused by sulfates. When used with frost resistant Alden aggregate in fly ash concrete and exposed to a variety of deicer brine compositions, the concrete did not deteriorate after exposure. With the exception of a high calcium brine, the behavior of the frost-prone Garrison aggregate was independent of deicer treatment; the high calcium brine reduced frost damage with this aggregate. Two approaches to reducing sulfate deterioration from deicers are suggested as (1) limiting the amount of sulfate to about 0.28 percent, and (2) making concrete sulfate-resistant by using fly ash. Techniques for making existing concrete deicer-sulfate-resistant are essential to a practical solution.
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The freeze-thaw resistance of concretes was studied. Nine concrete mixes, made with five cements and cement-Class C fly ash combinations, were exposed to freeze-thaw cycling following 110 to 222 days of moist curing. Prior to the freeze-thaw cycling, the specimens were examined by a low-vacuum scanning electron microscope (SEM) for their microstructure. The influence of a wet/dry treatment was also studied. Infilling of ettringite in entrained air voids was observed in the concretes tested. The extent of the infilling depends on the period of moist curing as well as the wet/dry treatment. The concretes with 15% Class C fly ash replacement show more infilling in their air voids. It was found that the influence of the infilling on the freeze-thaw durability relates to the air spacing factor. The greater the spacing factor, the more expansion under the freeze-thaw cycling. The infilling seems to decrease effective air content and to increase effective spacing factor. The infilling also implies that the filled air voids are water-accessible. These might lead to concrete more vulnerable to the freeze-thaw attack. By combining the above results with field observations, one may conclude that the freeze-thaw damage is a factor related to premature deterioration of portland cement concrete pavements in Iowa.
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Since the beginning of channel straightening at the turn of the century, the streams of western Iowa have degraded 1.5 to 5 times their original depth. This vertical degradation is often accompanied by increases in channel widths of 2 to 4 times the original widths. The deepening and widening of these streams has jeopardized the structural safety of many bridges by undercutting footings or pile caps, exposing considerable length of piling, and removing soil beneath and adjacent to abutments. Various types of flume and drop structures have been introduced in an effort to partially or totally stabilize these channels, protecting or replacing bridge structures. Although there has always been a need for economical grade stabilization structures to stop stream channel degradation and protect highway bridges and culverts, the problem is especially critical at the present time due to rapidly increasing construction costs and decreasing revenues. Benefits derived from stabilization extend beyond the transportation sector to the agricultural sector, and increased public interest and attention is needed.
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NYVAC-C (vP2010), a recombinant vector expressing HIV subtype C gag, pol, env and nef antigens, was tested in a phase I study in healthy, HIV negative volunteers in London and Lausanne. Twenty-four participants were randomised to receive NYVAC-C (20) or matching placebo (4) at weeks 0 and 4, and assessed for safety and immunogenicity over 48 weeks. There were no serious adverse events, and no clinical or laboratory abnormalities or other events that led to withdrawal, interruption or dose reduction of the NYVAC-C/placebo. Half of the 10 assessed responded in the ELISpot assay under stringent criteria, which informed the sample size for a DNA-NYVAC-C comparison to NYVAC-C alone.