RESUMEN
BACKGROUND: Farm exposures in early life reduce the risks for childhood allergic diseases and asthma. There is less information about how farm exposures relate to respiratory illnesses and mucosal immune development. OBJECTIVE: We hypothesized that children raised in farm environments have a lower incidence of respiratory illnesses over the first 2 years of life than nonfarm children. We also analyzed whether farm exposures or respiratory illnesses were related to patterns of nasal cell gene expression. METHODS: The Wisconsin Infant Study Cohort included farm (n = 156) and nonfarm (n = 155) families with children followed to age 2 years. Parents reported prenatal farm and other environmental exposures. Illness frequency and severity were assessed using illness diaries and periodic surveys. Nasopharyngeal cell gene expression in a subset of 64 children at age 2 years was compared to farm exposure and respiratory illness history. RESULTS: Farm versus nonfarm children had nominally lower rates of respiratory illnesses (rate ratio 0.82 [95% CI, 0.69, 0.97]) with a stepwise reduction in illness rates in children exposed to 0, 1, or ≥2 animal species, but these trends were nonsignificant in a multivariable model. Farm exposures and preceding respiratory illnesses were positively related to nasal cell gene signatures for mononuclear cells and innate and antimicrobial responses. CONCLUSIONS: Maternal and infant exposure to farms and farm animals was associated with nonsignificant trends for reduced respiratory illnesses. Nasal cell gene expression in a subset of children suggests that farm exposures and respiratory illnesses in early life are associated with distinct patterns of mucosal immune expression.
Asunto(s)
Exposición a Riesgos Ambientales , Granjas , Mucosa Nasal , Enfermedades Respiratorias , Humanos , Femenino , Animales , Masculino , Lactante , Exposición a Riesgos Ambientales/efectos adversos , Preescolar , Mucosa Nasal/inmunología , Enfermedades Respiratorias/inmunología , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/genética , Animales Domésticos/inmunología , Recién Nacido , Wisconsin/epidemiologíaRESUMEN
Epidemiologic and cross-sectional studies suggest that early life farming and animal exposures are associated with major health benefits, influencing immune development and modifying the subsequent risk of allergic diseases, including asthma. The Wisconsin Infant Study Cohort (WISC) study was established in central Wisconsin to test the hypothesis that early life animal farm exposures are associated with distinct innate immune cell maturation trajectories, decreased allergen sensitization and reduced respiratory viral illness burden during the first 2 years of life. Beginning in 2013, a total of 240 families have been enrolled, 16,522 biospecimens have been collected, and 4098 questionnaires have been administered and entered into a secure database. Study endpoints include nasal respiratory virus identification and respiratory illness burden score, allergic sensitization, expression of allergic disease, and anti-viral immune response maturation and profiles. The WISC study prospective design, broad biospecimen collections, and unique US rural community will provide insights into the role of environmental exposures on early life immune maturation profiles associated with protection from allergic sensitization and significant respiratory viral disease burden. The WISC study findings will ultimately inform development of new strategies to promote resistance to severe respiratory viral illnesses and design primary prevention approaches for allergic diseases for all infants.
Asunto(s)
Asma/diagnóstico , Exposición a Riesgos Ambientales/análisis , Granjas , Hipersensibilidad/diagnóstico , Adulto , Animales , Asma/epidemiología , Asma/etiología , Estudios Transversales , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Humanos , Hipersensibilidad/epidemiología , Hipersensibilidad/etiología , Lactante , Masculino , Edad Materna , Embarazo , Efectos Tardíos de la Exposición Prenatal/diagnóstico , Efectos Tardíos de la Exposición Prenatal/epidemiología , Efectos Tardíos de la Exposición Prenatal/etiología , Estudios Prospectivos , Proyectos de Investigación , Wisconsin/epidemiologíaRESUMEN
BACKGROUND: Allergy to German cockroach (CR) is common in urban environments and is an important allergen in children with asthma. OBJECTIVE: We hypothesize that the evolution of allergic sensitization and clinical disease is associated with distinct patterns of allergen-specific T cell reactivity. To test this hypothesis, a subset of high-risk inner-city children participating in the URECA (Urban Environment and Childhood Asthma) birth cohort were selected to evaluate CR-specific T cell reactivity from three distinct groups based on acquisition of aeroallergen sensitivity from ages 2 to 10: low atopy with minimal to no sensitivity (n = 26), early-onset allergic sensitization (n = 25) and late-onset allergic sensitization (n = 25). METHODS: Using pools of previously identified CR-derived T cell epitopes, we characterized the allergen-specific T cell response in these 76 subjects from blood samples obtained at age 10. CR-specific production of IL-5, IFNγ and IL-10 was measured by ELISPOT following two-week in vitro culture with CR extract. RESULTS: T cell responses were significantly higher in the early-onset atopy group compared to low atopy (P = 0.01), and a trend for higher cytokine production in the late onset compared to the low atopy cohort was also observed (P = 0.06). T cell responses were similar between early- and late-onset cohorts. Furthermore, a comparison of T cell reactivity between asthmatic and non-asthmatic individuals revealed significantly higher cytokine production in asthmatics compared to non-asthmatics (P = 0.02) within both the CR-allergic and non-allergic cohorts. CONCLUSIONS AND CLINICAL RELEVANCE: In conclusion, the present study reports that higher T cell reactivity is associated with allergen sensitization and asthma. Interestingly, no significant difference in T cell reactivity was observed in allergic children with early-onset versus late-onset atopy.
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Alérgenos/inmunología , Asma/diagnóstico , Asma/inmunología , Blattellidae/inmunología , Epítopos de Linfocito T/inmunología , Edad de Inicio , Animales , Asma/epidemiología , Asma/patología , Niño , Preescolar , Citocinas/inmunología , Femenino , Humanos , MasculinoRESUMEN
BACKGROUND: Disadvantaged urban children have high rates of allergic diseases and wheezing, which are diseases associated with type 2-biased immunity. OBJECTIVE: We sought to determine whether environmental exposures in early life influence cytokine responses that affect the development of recurrent wheezing illnesses and allergic sensitization. METHODS: A birth cohort of 560 urban families was recruited from neighborhoods with high rates of poverty, and 467 (83%) children were followed until 3 years of age. Cytokine responses were measured in blood cell samples obtained at birth (cord blood) and ages 1 and 3 years. Cytokine responses were examined in relation to personal characteristics and environmental exposures to allergens and endotoxin and to the development of allergic sensitization and recurrent wheeze assessed at age 3 years. RESULTS: Cytokine responses generally increased with age, but responses at birth were poorly predictive for those at ages 1 and 3 years. Exposure to certain allergens (cockroach, mouse, dust mite) was significantly associated with enhanced cytokine responses at age 3 years, including IFN-α and IL-10 responses to certain stimulants and responses to phytohemagglutinin. Regarding the clinical outcomes, reduced LPS-induced IL-10 responses at birth were associated with recurrent wheeze. In contrast, reduced respiratory syncytial virus-induced IL-8 responses and increased 5'-cytosine-phosphate-guanine-3' (CpG)-induced IL-12p40 and allergen-induced IL-4 responses were associated with atopy. CONCLUSIONS: These findings suggest that diverse biologic exposures, including allergens and endotoxin, in urban homes stimulate the development of cytokine responses in early life, and that cytokine responses to specific microbial and viral stimuli are associated with the development of allergic sensitization and recurrent wheeze.
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Exposición a Riesgos Ambientales/efectos adversos , Hipersensibilidad Inmediata/inmunología , Ruidos Respiratorios/inmunología , Alérgenos/inmunología , Preescolar , Ciudades/epidemiología , Citocinas/inmunología , Polvo/análisis , Endotoxinas/inmunología , Exposición a Riesgos Ambientales/análisis , Femenino , Vivienda , Humanos , Hipersensibilidad Inmediata/sangre , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/epidemiología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Lactante , Lipopolisacáridos/inmunología , Masculino , Oportunidad Relativa , Pruebas Cutáneas , Estados Unidos/epidemiología , Población UrbanaRESUMEN
Asthma in the inner-city population is usually atopic in nature, and is associated with significant morbidity and mortality. However, the underlying immune abnormalities that underlie asthma in urban adults have not been well defined. We investigated the influence of atopy and asthma on cytokine responses of inner-city adult women to define immune abnormalities associated with asthma and atopy. Blood samples were collected from 509 of 606 inner-city women enrolled in the Urban Environment and Childhood Asthma (URECA) study. We tested for associations between atopy and asthma status and cytokine responses in peripheral blood mononuclear cells incubated ex vivo with a panel of innate and adaptive immune stimulants. Atopic subjects had heightened Th2 cytokine responses (IL-4, IL-5, IL-13) to cockroach and dust mite antigens, tetanus toxoid, and phytohemagglutinin (P < 0.05 for all). Differences in cytokine responses were greatest in response to stimulation with cockroach and dust mite. In a multivariate analysis, atopy was broadly related to increased Th2-like responses to all antigens and PHA, while asthma was only weakly related to mitogen-induced IL-4 and IL-5 responses. There were few asthma or allergy-related differences in responses to innate stimuli, including IFN-α and IFN-γ responses. In this inner-city adult female population, atopy is associated with enhanced Th2 responses to allergens and other stimuli, and there was little or no additional signal attributable to asthma. In particular, these data indicate that altered systemic interferon and innate immune responses are not associated with allergies and/or asthma in inner-city women.
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Asma/sangre , Sangre Fetal/metabolismo , Vitamina D/sangre , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Embarazo/sangreRESUMEN
BACKGROUND: The Urban Environment and Childhood Asthma study was established to investigate the immunologic and environmental causes of asthma in inner-city children. OBJECTIVE: We sought to evaluate potential atopic outcomes in the first 12 months and their relationships to environmental exposures and immune development. METHODS: A birth cohort of 560 children with at least 1 parent with allergy or asthma was established in Baltimore, Boston, New York, and St Louis. Wheezing is assessed every 3 months, allergen-specific IgE yearly, and mononuclear cell cytokine responses at birth and yearly; environmental assessments include dust allergen and endotoxin, maternal stress, and indoor nicotine and nitrogen dioxide levels. RESULTS: Key outcomes in the first year include wheeze in 49%, 2 or more episodes of wheeze in 23%, eczema in 30%, and detectable IgE to milk, egg, and/or peanut in 32% and to cockroach in 4%. Household dust revealed levels of greater than 2 µg/g to cockroach in 40%, mite in 19%, cat in 25%, and mouse in 29%, and 66% of homes housed at least 1 smoker. Positive associations were detected between multiple wheeze and cotinine levels, maternal stress, and maternal depression, whereas cytokine responses to a variety of innate, adaptive, and mitogenic stimuli were inversely related to eczema. CONCLUSIONS: This high-risk cohort of inner-city infants is exhibiting high rates of wheeze, eczema, and allergic sensitization. Low cytokine responses at birth might be a risk factor for eczema, whereas a variety of adverse environmental exposures contribute to the risk of wheezing in infancy. These findings provide evidence of specificity in the interactions between immune development, environmental exposures, and the development of early features that might predict future asthma.
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Contaminantes Atmosféricos/efectos adversos , Citocinas/inmunología , Exposición a Riesgos Ambientales/efectos adversos , Sangre Fetal/inmunología , Hipersensibilidad/epidemiología , Ruidos Respiratorios/etiología , Alérgenos/inmunología , Animales , Baltimore/epidemiología , Boston/epidemiología , Estudios de Cohortes , Eccema/epidemiología , Eccema/etiología , Eccema/inmunología , Femenino , Humanos , Hipersensibilidad/etiología , Hipersensibilidad/inmunología , Lactante , Masculino , New York/epidemiología , Ruidos Respiratorios/inmunología , Salud UrbanaRESUMEN
PURPOSE: In this single institution Phase II trial, we evaluated the efficacy of the vitamin D analogue, 1alpha-OH-D(2), in patients with advanced hormone-refractory prostate cancer. EXPERIMENTAL DESIGN: The patients initially received 1alpha-OH-D(2) at 12.5 micro g p.o. every day, which was dose adjusted for hypercalcemia. Given the cytostatic nature of the drug, the primary study end point was progression-free survival for a minimum of 6 months. The secondary end point was further characterization of drug toxicity. RESULTS: A total of 26 patients was enrolled. Using the intent-to-treat population, stable disease was seen for an average of 19.2 weeks (median 12 weeks, range 3-108 weeks). Twenty patients were evaluable for response. The one patient that achieved disease stabilization for >2 years elected to come off-study because of patient preference. His last disease evaluation showed no evidence of progression. No objective responses were seen. Previous and ongoing clinical observations strongly imply that PSA could be a misleading surrogate marker for clinical effect with this type of drug. Therefore, prostate-specific antigen was not used as a marker for disease response. Toxicity was as expected with mild hypercalcemia and associated symptoms like constipation and prerenal azotemia seen in some patients. Six (30%) evaluable patients experienced stable disease for >6 months, suggesting possible cytostatic activity. CONCLUSION: The results of this and other trials suggest further clinical investigation in this disease with vitamin D analogues alone or in combination with other agents, such as chemotherapy, should be pursued.
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Ergocalciferoles/toxicidad , Ergocalciferoles/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Administración Oral , Anciano , Anciano de 80 o más Años , Andrógenos/análisis , Ergocalciferoles/administración & dosificación , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Osteocalcina/sangre , Cuidados Paliativos , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Análisis de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
PURPOSE: Endostatin is the first endogenous angiogenesis inhibitor to enter clinical trials. Laboratory investigations with endostatin have indicated broad antitumor activity coupled with remarkably low toxicity. A phase I trial of recombinant human endostatin was designed to evaluate toxicity and explore biologic effectiveness in patients with refractory solid tumors. PATIENTS AND METHODS: Endostatin was administered as a 1-hour intravenous infusion given daily for a 28-day cycle. A starting dose of 30 mg/m2 was explored with subsequent dose escalations of 60, 100, 150, 225, and 300 mg/m2. Assessment of serum pharmacokinetics was performed on all 21 patients. Western blot assay and mass spectroscopy were employed to evaluate endostatin metabolism. Circulating levels of endogenous proangiogenic growth factors were examined. Tumor and tumor blood supply were imaged by dynamic computed tomography (CT), magnetic resonance imaging, ultrasound, and positron emission tomography. RESULTS: Endostatin given on this schedule was essentially free of significant drug-related toxicity. Two transient episodes of grade 1 rash were observed. No clinical responses were observed. Endostatin pharmacokinetics were linear with dose, and serum concentrations were achieved that are associated with antitumor activity in preclinical models. No aggregate effect on circulating proangiogenic growth factors were seen, although several patients exhibited persistent declines in vascular endothelial growth factor levels while enrolled in the study. A few patients demonstrated changes in their dynamic CT scans suggestive of a decline in microvessel density, although overall, no consistent effect of endostatin on tumor vasculature was seen. CONCLUSION: Endostatin given daily as a 1-hour intravenous infusion was well tolerated without dose-limiting toxicity at doses up to 300 mg/m2.
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Inhibidores de la Angiogénesis/farmacocinética , Colágeno/farmacocinética , Neoplasias/metabolismo , Neovascularización Patológica/metabolismo , Fragmentos de Péptidos/farmacocinética , Adulto , Anciano , Inhibidores de la Angiogénesis/farmacología , Western Blotting , Colágeno/farmacología , Diagnóstico por Imagen , Relación Dosis-Respuesta a Droga , Endostatinas , Factores de Crecimiento Endotelial/sangre , Femenino , Factor 2 de Crecimiento de Fibroblastos/sangre , Humanos , Infusiones Intravenosas , Péptidos y Proteínas de Señalización Intercelular/sangre , Linfocinas/sangre , Masculino , Persona de Mediana Edad , Neoplasias/irrigación sanguínea , Neoplasias/diagnóstico , Neovascularización Patológica/diagnóstico , Fragmentos de Péptidos/farmacología , Proteínas Recombinantes , Distribución Tisular , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
PURPOSE: Flavopiridol (NSC 649890) is a synthetic flavone possessing significant antitumor activity in preclinical models. Flavopiridol is capable of inducing cell cycle arrest and apoptosis, presumably through its potent, specific inhibition of cyclin-dependent kinases. We conducted a phase I trial and pharmacokinetic study of flavopiridol given as a 72-h continuous intravenous infusion repeated every 2 weeks. METHODS: A total of 38 patients were treated at dose levels of 8, 16, 26.6, 40, 50 and 56 mg/m(2)/24 h. During the first infusion, plasma was sampled at 24, 48 and 72 h to determine steady-state concentrations, and peripheral blood lymphocytes were assessed by flow cytometry for evidence of apoptosis. Additional postinfusion pharmacokinetic sampling was done at the 40 and 50 mg/m(2)/24 h dose levels. RESULTS: Gastrointestinal toxicity was dose limiting, with diarrhea being the predominant symptom. Symptomatic orthostatic hypotension was also frequently noted. Several patients experienced tumor-specific pain during their infusions. The maximum tolerated dose (MTD) was determined to be 40 mg/m(2)/24 h. A patient with metastatic gastric cancer at this dose level had a complete response and remained disease-free for more than 48 months after completing therapy. Plasma concentrations at 24 h into the infusion were 94% of those achieved at steady state. Steady-state plasma flavopiridol concentrations at the MTD were 416.6+/-98.9 micro M. These concentrations are at or above those needed to see cell cycle arrest and apoptosis in vitro. The mean clearance of flavopiridol over the dose range was 11.3+/-3.9 l/h per m(2), similar to values obtained preclinically. Elimination was biphasic. The terminal half-life at the MTD was 26.0 h. No significant differences in pharmacokinetic parameters were noted between males and females. Patients taking cholestyramine to ameliorate flavopiridol-induced diarrhea had lower steady-state plasma concentrations. There was no significant change in the cell cycle parameters of peripheral blood lymphocytes analyzed by flow cytometry. CONCLUSIONS: The MTD and recommended phase II dose of flavopiridol given by this schedule is 40 mg/m(2)/24 h. The manageable gastrointestinal toxicity, early signs of clinical activity and lack of hematologic toxicity make further exploration in combination trials warranted.
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Antineoplásicos/farmacocinética , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacocinética , Flavonoides/farmacocinética , Neoplasias/metabolismo , Piperidinas/farmacocinética , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Femenino , Citometría de Flujo , Semivida , Humanos , Infusiones Intravenosas , Masculino , Dosis Máxima Tolerada , Tasa de Depuración Metabólica , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Seguridad , Resultado del TratamientoRESUMEN
PURPOSE: NSC 655649 was given in both single- and multiple-dose formats, to characterize maximum tolerated dose (MTD), toxicity, and pharmacokinetic profile. EXPERIMENTAL DESIGN: Patients with advanced malignancies were treated with escalating doses of NSC 655649 in either a single-dose format (step 1) or a multiple-dose format (step 2). In step 1, NSC 655649 was given as a 30-60 min infusion. In step 2, the NSC 655649 dose was divided into three consecutive daily doses. Plasma and urine were sampled to assess the pharmacokinetic and excretory characteristics of NSC 655649. A total of 12 patients were enrolled at the MTD for the purpose of gender equity. RESULTS: Forty-three patients were treated with NSC 655649 for a total of 108 cycles in step 1, and 26 patients were treated for a total of 41 cycles in step 2. The MTD for both steps 1 and 2 was determined to be 572 mg/m(2). Myelosuppression was the dose-limiting toxicity. Local venous irritation was generally grade 1-2 in severity but could only be adequately prevented by administration of study drug through central i.v. access. One patient with adenocarcinoma of unknown primary experienced a partial response on step 1. Four patients experienced stable disease of >100 days duration. CONCLUSIONS: NSC 655649 may be safely given at an MTD of 572 mg/m(2) in both single-dose and multiple-dose formats. Optimally, this drug should be administered through central i.v. access.
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Aminoglicósidos , Antibacterianos/farmacocinética , Antineoplásicos/farmacocinética , Neoplasias/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Carbazoles , Relación Dosis-Respuesta a Droga , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Glucósidos , Humanos , Infusiones Intravenosas , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neutropenia/inducido químicamente , Trombocitopenia/inducido químicamenteRESUMEN
Penclomedine is a synthetic alpha-picoline derivative that has shown antitumor activity both in preclinical development and in Phase I work using an i.v. preparation. The main toxicities seen in those studies were dose dependent and mainly neurocerebellar, with hematological toxicity being far less severe. This Phase I trial of p.o. penclomedine was conducted to potentially alter the toxicity profile and to avoid the neurological side effects seen with i.v. penclomedine. Eligibility criteria included microscopic confirmation of a solid malignancy or lymphoma with a lack of effective anticancer therapy. Twenty patients were enrolled. The median age was 60.5 years, and the median performance status was one. All but one patient had received prior systemic therapy. The starting dose of penclomedine was 200 mg/m(2) p.o. for 5 days, and was escalated according to a traditional Fibonacci sequence until the maximum tolerated dose (MTD) was observed. No treatment-related deaths were observed during the study. The MTD was determined to be 800 mg/m(2) p.o. for 5 days. Dose-limiting toxicities included mainly neurocerebellar symptoms such as ataxia and dysmetria, but neurocortical symptoms, such as confusion, were seen as well. Myelosuppression was less common and resulted in the discontinuation of therapy in only two patients. Pharmacokinetics show that the observed MTD is consistent with the i.v. preparations, and that the bioavailability of p.o. penclomedine is 49 +/- 18%. This regimen can be considered for additional studies in patients with intracranial neoplasms, because good central nervous system penetration is evident. Further development of penclomedine metabolites, such as 4-O-demethylpenclomedine, should be considered to minimize dose-limiting neurotoxicity.
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Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Neoplasias/tratamiento farmacológico , Picolinas/administración & dosificación , Picolinas/farmacocinética , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Ataxia Cerebelosa/inducido químicamente , Mareo/inducido químicamente , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Náusea/inducido químicamente , Neoplasias/metabolismo , Picolinas/efectos adversosRESUMEN
PURPOSE: This Phase I study was conducted to evaluate the toxicity profile and determine the maximum tolerated dose (MTD) of an oral micronized formulation of the signal transduction inhibitor carboxyamidotriazole (CAI). Bioavailability of the micronized formulation relative to a gelatin capsule (gelcap) formulation was assessed. The effects of food intake and timing on CAI steady-state plasma concentrations (C(ss)) were also investigated. EXPERIMENTAL DESIGN: Patients received continuous daily CAI (28-day cycles). Starting dose was 150 mg/m(2) daily and escalations were by 50 mg/m(2) increments. The first three patients enrolled were given test doses of the original gelcap formulation and two different micronized formulations to determine relative bioavailability. Toxicity and pharmacokinetic assessments were performed weekly. Additional cohorts were added after MTD determination to assess the effect of food intake and duration of fast on CAI C(ss). RESULTS: The micronized formulation was absorbed more slowly than the gelcap formulation. Twenty-nine patients were enrolled in the dose-escalation portion of the study. After dose escalation to 300 mg/m(2), dose-limiting neurotoxicities occurred including reversible vision loss in two patients. Other toxicities were mild. The final MTD was 150 mg/m(2). Pharmacokinetics appeared linear with significant inter- and intrapatient variability. Patients with C(ss) of > or = 4.0 mg/liter were more likely to have neurotoxicity. Nine patients with renal cell cancer and one with hepatocellular cancer had prolonged stable disease. CAI plasma concentrations were higher when taken with food. CONCLUSIONS: Micronized CAI was well tolerated at the MTD of 150 mg/m(2). Higher doses were limited by significant neurotoxicity. The variability in CAI pharmacokinetics may be partially attributable to concomitant food intake and timing of the dose.