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1.
Am J Emerg Med ; 42: 188-191, 2021 04.
Article in English | MEDLINE | ID: mdl-32151369

ABSTRACT

OBJECTIVES: The objective of this study was to determine physician awareness of abnormal vital signs and key clinical interventions (oxygen provision, intravenous access) in the emergency department, and to measure the effect of patient handoffs on this awareness. METHODS: This was a prospective observational study at two large, urban, academic emergency departments. Emergency department physicians were asked the following about each of the physician's patients: 1) the number of IV lines, 2) whether the patient was on supplemental oxygen, and 3) whether the patient had any abnormal vital signs. Physicians were blind to the nature of the study prior to enrollment. Error rates between physician responses and actual patient status were calculated, and logistic regression, adjusted for physician clustering, was used to calculate association of errors with multiple situational factors, including handoff status. RESULTS: We analyzed 463 patient encounters from 74 physicians. Physicians missed abnormal vital signs in 19.4% of encounters. They made errors in oxygen status and number of IV lines in 16.6% and 35.8% of encounters, respectively. Physicians were significantly more likely to make all types of errors on patients who had undergone handoff as opposed to their primary patients. CONCLUSION: Emergency physicians make frequent errors regarding awareness of their patients' vital signs, oxygen and vascular status and patient handoffs are associated with an increased frequency of such errors.


Subject(s)
Communication , Emergency Service, Hospital/standards , Medical Errors/statistics & numerical data , Patient Handoff/standards , Vital Signs , Female , Humans , Indiana , Logistic Models , Male , Medical Errors/prevention & control , Patient Safety , Physicians , Prospective Studies
2.
J Pediatr Endocrinol Metab ; 29(9): 1089-93, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27487489

ABSTRACT

Permanent neonatal diabetes (PNDM) is a rare genetic condition characterized by hyperglycemia, insulinopenia, and failure to thrive beginning in the first 6 months of life. Recessive mutations in INS lead to decreased production of insulin via a variety of mechanisms. We present a case of two brothers, born to consanguineous parents, with a novel homozygous intronic variant in the INS gene. Each patient presented with intrauterine growth restriction (IUGR) and significant hyperglycemia within the first 24 h of life. All the grandparents have a diagnosis of diabetes, one of them requiring insulin treatment and the parents currently deny personal histories of diabetes. Although this mutation has not previously been described, given the segregation of the mutation, absence of heterozygosity (AOH) in the genomic region encompassing the INS locus, documented insulinopenia, and high neonatal insulin requirements, we suspect that this variant is pathogenic. Possible implications for personalized treatment of the underlying molecular etiology for an individual's diabetes are discussed.


Subject(s)
Diabetes Mellitus/etiology , Insulin/genetics , Introns/genetics , Mutation/genetics , Adult , Consanguinity , Female , Homozygote , Humans , Infant, Newborn , Male , Pedigree , Prognosis , Siblings
3.
J Food Prot ; 79(10): 1767-1774, 2016 10.
Article in English | MEDLINE | ID: mdl-28221844

ABSTRACT

The requirement for validation of allergen cleaning processes is increasing. The use of lateral flow devices (LFDs) to identify allergens has rapidly expanded, but the best practices for use of these devices are still developing. The goal of this study was to compare commercially available milk-specific LFDs and a general protein identification method. Five milk proteins and seven milk-derived ingredients were tested at several concentrations with eight milk-specific LFDs and a general protein identification kit. Nonfat dry milk (NFDM) was prepared at 100 to 10,000 ppm of milk protein and analyzed by the LFDs to determine the concentration at which a false-negative result (overload concentration or hook effect) was obtained. NFDM was also prepared in 0.025 M phosphate-buffered saline (pH 7.4, 0.85% NaCl) and applied to stainless steel panels (100, 30, 10, or 3 µg of NFDM protein) with various drying methods and sampled with various swab methods to determine the level of detectability. Several total milk LFD kits did not detect whey proteins or whey-derived ingredients. The overload concentration of the various kits ranged from 100 to 10,000 ppm of milk protein. The small dynamic range observed for some kits would necessitate multiple dilutions of a sample to ensure that the result would fall within the range of detection. For swab sampling of stainless steel for LFD analysis, milk protein residues from surfaces onto which the residues were dried with high heat were more difficult to detect than were residues dried with low heat. No differences in sensitivity were observed as a result of moistening the residue or the swab before sampling. These results highlight the importance of understanding the detection capabilities of LFDs as indicated by the variability in the performance of the milk-specific LFDs tested.


Subject(s)
Milk Proteins , Milk/chemistry , Allergens , Animals , Hot Temperature
4.
Lancet Haematol ; 2(8): e339-46, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26688487

ABSTRACT

BACKGROUND: Activation of the Hedgehog signalling pathway contributes to cancer progression and the development of myeloid leukaemia stem cell therapeutic resistance. We aimed to identify the maximum tolerated dose (MTD) and the recommended phase 2 dose of the selective Hedgehog antagonist PF-04449913 in myeloid malignancies. METHODS: We undertook an open-label, dose-finding, standard 3+3 design phase 1 study of PF-04449913 in adult patients with acute myeloid leukaemia, chronic myeloid leukaemia, chronic myelomonocytic leukaemia, myelodysplastic syndrome, or myelofibrosis who were refractory, resistant, or intolerant to previous treatments, at three centres in the USA and one in Italy. Patients who had newly diagnosed, untreated disease were included if they were not eligible for standard treatment options or if standard treatments were not deemed appropriate. Patients received PF-04449913 once daily continuously until disease progression, unacceptable toxic effects, or patient withdrawal for up to 12 28-day cycles. Additional cycles were given if patients showed evidence of clinical benefit. The starting dose was 5 mg and was increased by 100% until the first dose-limiting toxic effect (DLT) and by 50% thereafter, in keeping with a 3+3 clinical trial statistical design. The primary endpoint was first-cycle DLTs. Secondary endpoints were safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary clinical activity. This trial is registered with ClinicalTrials.gov, number NCT00953758. FINDINGS: Between March 24, 2010, and Sept 7, 2012, 47 patients were enrolled and included in the study: 28 with acute myeloid leukaemia, six with myelodysplastic syndrome, five with chronic myeloid leukaemia (two with chronic-phase and three with blast-phase disease), one with chronic myelomonocytic leukaemia, and seven with myelofibrosis. Patients received PF-04449913 once daily at 5 mg (n=3), 10 mg (n=3), 20 mg (n=4), 40 mg (n=4), 80 mg (n=8), 120 mg (n=3), 180 mg (n=3), 270 mg (n=5), 400 mg (n=9), and 600 mg (n=5). Two patients experienced DLTs (one each in the 80 mg and 600 mg dose groups). The MTD for PF-04449913 was established to be 400 mg once daily. Of the 47 patients enrolled, 28 (60%) experienced treatment-related adverse events, three of which were grade 4 in severity. The most common treatment-related adverse events included dysgeusia (13 [28%] patients), decreased appetite (nine [19%]), and alopecia (seven [15%]). None of the 15 deaths reported were treatment related. Pharmacokinetics seemed to be dose proportional. The mean half-life was 23·9 h (SD 14·0) in the MTD group. Some suggestion of clinical activity was noted in 23 (49%) of 47 patients with haematological malignancies. Based on these results, the recommended phase 2 dose was 200 mg or lower once daily. INTERPRETATION: Based on these findings, PF-04449913 is being tested in phase 2 studies in patients with myelodysplastic syndrome, acute myeloid leukaemia, and myelofibrosis. FUNDING: Pfizer.


Subject(s)
Benzimidazoles/pharmacokinetics , Benzimidazoles/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Myelodysplastic Syndromes/drug therapy , Phenylurea Compounds/pharmacokinetics , Phenylurea Compounds/therapeutic use , Primary Myelofibrosis/drug therapy , Administration, Oral , Half-Life , Humans , Italy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Maximum Tolerated Dose , Treatment Outcome , United States
5.
Clin Cancer Res ; 21(5): 1044-51, 2015 03 01.
Article in English | MEDLINE | ID: mdl-25388167

ABSTRACT

PURPOSE: To estimate the maximum tolerated dose (MTD) of single-agent PF-04449913, and to evaluate safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity in patients with advanced tumors. EXPERIMENTAL DESIGN: A 3+3 design was used in this open-label, multicenter, phase I study and dose escalation/de-escalation applied until identification of the MTD. PF-04449913 was orally administered once daily in continuous 28-day treatment cycles. The starting dose was 80 mg. RESULTS: A total of 23 patients were enrolled; 19 were evaluable for first-cycle dose-limiting toxicity (DLT). The first-cycle DLT rate at the 640 mg dose level was 33.3%, and the MTD was estimated to be 320 mg once daily. The recommended phase II dose was not determined. PF-04449913 was generally well tolerated at doses of 80 to 320 mg once daily. The most common treatment-related adverse events (AE) were grade 1-2 dysgeusia, fatigue, decreased appetite, nausea, dizziness, dehydration, and diarrhea. Treatment-related grade 3 AEs only occurred in patients receiving PF-04449913 640 mg once daily. No treatment-related grade 4-5 AEs were reported. Pharmacokinetic analysis indicated a generally dose-proportional kinetics with biphasic elimination, supporting once-daily dosing. PF-04449913 modulated hedgehog signaling at the dose levels tested, as demonstrated by >80% downregulation of GLI1 expression in the skin of treated patients. Eight patients (34.8%) achieved stable disease; none had complete or partial response. Three patients with disease progression at enrollment had prolonged disease stabilization (≥6 months). CONCLUSIONS: The results obtained in this study support further evaluation of PF-04449913 in patients with advanced solid tumors.


Subject(s)
Antineoplastic Agents/therapeutic use , Benzimidazoles/therapeutic use , Hedgehog Proteins/antagonists & inhibitors , Neoplasms/drug therapy , Neoplasms/pathology , Phenylurea Compounds/therapeutic use , Administration, Oral , Adult , Aged , Antineoplastic Agents/pharmacology , Benzimidazoles/pharmacology , Female , Gene Expression , Humans , Male , Maximum Tolerated Dose , Middle Aged , Neoplasm Staging , Neoplasms/diagnosis , Neoplasms/genetics , Oncogene Proteins/genetics , Phenylurea Compounds/pharmacology , Trans-Activators/genetics , Treatment Outcome , Zinc Finger Protein GLI1
6.
Blood ; 119(20): 4597-607, 2012 May 17.
Article in English | MEDLINE | ID: mdl-22383795

ABSTRACT

Mantle cell lymphoma (MCL) carries an unfavorable prognosis and requires new treatment strategies. The associated t(11:14) translocation results in enhanced cyclin D1 expression and cyclin D1-dependent kinase activity to promote cell-cycle progression. A pharmacodynamic study of the selective CDK4/6 inhibitor PD0332991 was conducted in 17 patients with relapsed disease, using 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) and 3-deoxy-3[(18)F]fluorothymidine (FLT) positron emission tomography (PET) to study tumor metabolism and proliferation, respectively, in concert with pre- and on-treatment lymph node biopsies to assess retinoblastoma protein (Rb) phosphorylation and markers of proliferation and apoptosis. Substantial reductions in the summed FLT-PET maximal standard uptake value (SUV(max)), as well as in Rb phosphorylation and Ki-67 expression, occurred after 3 weeks in most patients, with significant correlations among these end points. Five patients achieved progression-free survival time of > 1 year (range, 14.9-30.1+ months), with 1 complete and 2 partial responses (18% objective response rate; 90% confidence interval, 5%-40%). These patients demonstrated > 70%, > 90%, and ≥ 87.5% reductions in summed FLT SUV(max) and expression of phospho-Rb and Ki67, respectively, parameters necessary but not sufficient for long-term disease control. The results of the present study confirm CDK4/6 inhibition by PD0332991 at a well-tolerated dose and schedule and suggest clinical benefit in a subset of MCL patients. This study is registered at www.clinicaltrials.gov under identifier NCT00420056.


Subject(s)
Lymphoma, Mantle-Cell/drug therapy , Piperazines/therapeutic use , Pyridines/therapeutic use , Adult , Aged , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Antineoplastic Agents/therapeutic use , Cyclin-Dependent Kinase 4/antagonists & inhibitors , Cyclin-Dependent Kinase 6/antagonists & inhibitors , Female , Humans , Lymphoma, Mantle-Cell/blood , Lymphoma, Mantle-Cell/diagnosis , Lymphoma, Mantle-Cell/metabolism , Male , Middle Aged , Piperazines/administration & dosage , Piperazines/adverse effects , Piperazines/pharmacokinetics , Prognosis , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/adverse effects , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/therapeutic use , Pyridines/administration & dosage , Pyridines/adverse effects , Pyridines/pharmacokinetics , Substrate Specificity , Treatment Outcome
7.
Clin Cancer Res ; 18(2): 568-76, 2012 Jan 15.
Article in English | MEDLINE | ID: mdl-22090362

ABSTRACT

PURPOSE: To identify the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) of the first-in-class, oral CDK4/6 inhibitor PD 0332991 administered once daily for 21 of 28 days (3/1 schedule) in patients with retinoblastoma protein (Rb)-positive advanced solid tumors and to describe pharmacokinetic-pharmacodynamic relationships relative to drug effects. EXPERIMENTAL DESIGN: This open-label phase I study (NCT00141297) enrolled patients who received PD 0332991 orally in six dose-escalation cohorts in a standard 3 + 3 design. RESULTS: Forty-one patients were enrolled. DLTs were observed in five patients (12%) overall; at the 75, 125, and 150 mg once daily dose levels. The MTD and recommended phase II dose of PD 0332991 was 125 mg once daily. Neutropenia was the only dose-limiting effect. After cycle 1, grade 3 neutropenia, anemia, and leukopenia occurred in five (12%), three (7%), and one (2%) patient(s), respectively. The most common non-hematologic adverse events included fatigue, nausea, and diarrhea. Thirty-seven patients were evaluable for tumor response; 10 (27%) had stable disease for ≥4 cycles of whom six derived prolonged benefit (≥10 cycles). PD 0332991 was slowly absorbed (median T(max), 5.5 hours), and slowly eliminated (mean half-life was 25.9 hours) with a large volume of distribution (mean, 2,793 L). The area under the concentration-time curve increased linearly with dose. Using an E(max) model, neutropenia was shown to be proportional to exposure. CONCLUSIONS: PD 0332991 warrants phase II testing at 125 mg once daily, at which dose neutropenia was the sole significant toxicity.


Subject(s)
Antineoplastic Agents/administration & dosage , Maximum Tolerated Dose , Neoplasms/drug therapy , Piperazines/administration & dosage , Pyridines/administration & dosage , Administration, Oral , Adult , Aged , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/toxicity , Area Under Curve , Cyclin-Dependent Kinases/antagonists & inhibitors , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , Neutropenia/chemically induced , Piperazines/pharmacokinetics , Piperazines/toxicity , Pyridines/pharmacokinetics , Pyridines/toxicity , Treatment Outcome , Young Adult
8.
Curr Eye Res ; 36(9): 809-17, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21851167

ABSTRACT

PURPOSE: To evaluate the safety of escalating doses of taprenepag isopropyl (PF-04217329), a selective EP(2) receptor agonist administered as a topical ophthalmic solution, versus its vehicle (Stage I), and dose-response of taprenepag isopropyl alone and in unfixed combination with latanoprost ophthalmic solution 0.005% versus latanoprost alone (Stage II). SUBJECTS AND METHODS: Randomized, vehicle- and active-controlled, double-masked, two-stage, dose-finding trial in primary open-angle glaucoma (POAG) or ocular hypertension; first taprenepag isopropyl study in patients (NCT00572455). Study eye: 26 mmHg ≤ intraocular pressure (IOP) <36 mmHg at 8 am and 22 mmHg ≤ IOP <36 mmHg at 10 am, 1 pm, 4 pm. Stage I: 3 cohorts (total n = 67) received 1 drop of taprenepag isopropyl unit dose formulation qPM/eye for 14 days: low dose: 0.0025%, 0.005%, vehicle; middle dose: 0.01%, 0.015%, vehicle; high dose: 0.02%, 0.03%, vehicle. Stage II: 7 groups (total n = 250) received 1 drop of taprenepag isopropyl multidose formulation qPM/eye for 28 days: 0.005%, 0.01%, 0.015% monotherapy; each in unfixed combination with latanoprost 0.005%, or latanoprost monotherapy. MAIN OUTCOMES: mean change in diurnal IOP, baseline to last visit; adverse events. RESULTS: Stage I at day 14: statistically significantly greater IOP reductions were observed at all taprenepag isopropyl doses versus vehicle. Stage II at day 28: statistically significantly greater IOP reductions were observed at all doses of the unfixed combination versus latanoprost monotherapy. At least 1 treatment-emergent adverse event reported for 29/67 (43.3%) subjects in Stage I and 158/250 (63.2%) in Stage II. CONCLUSIONS: Taprenepag isopropyl significantly reduces IOP in POAG and ocular hypertension. Taprenepag isopropyl monotherapy is comparable to latanoprost 0.005% in reducing IOP. As demonstrated in this report, the activity of taprenepag isopropyl is additive to that of latanoprost 0.005%. Further studies are required to determine whether it shows similar additivity when administered with other ocular antihypertensive medications.


Subject(s)
Acetates/administration & dosage , Glaucoma, Open-Angle/drug therapy , Intraocular Pressure/drug effects , Ocular Hypertension/drug therapy , Prostaglandins F, Synthetic/administration & dosage , Sulfonamides/administration & dosage , Adult , Aged , Aged, 80 and over , Antihypertensive Agents/administration & dosage , Dose-Response Relationship, Drug , Double-Blind Method , Female , Follow-Up Studies , Glaucoma, Open-Angle/physiopathology , Humans , Latanoprost , Male , Middle Aged , Ocular Hypertension/physiopathology , Ophthalmic Solutions , Prospective Studies , Receptors, Prostaglandin E, EP2 Subtype/antagonists & inhibitors , Treatment Outcome
9.
Ophthalmology ; 118(10): 2022-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21788077

ABSTRACT

OBJECTIVE: To evaluate short-term safety and steady-state systemic pharmacokinetics (PK) of latanoprost acid in pediatric subjects with glaucoma or ocular hypertension who received the adult latanoprost dose. DESIGN: Phase 1, open-label, multicenter study. PARTICIPANTS: Pediatric patients of 3 age groups (<3, 3-<12, and 12-<18 years) and adults (≥18 years) receiving latanoprost ophthalmic solution 0.005% once daily in 1 or both eyes for ≥2 weeks. INTERVENTION: Latanoprost was administered in both eyes each morning post-screening. Subjects returned 3 to 28 days later for evaluation of plasma concentrations, withholding morning latanoprost. At the clinic, a single drop of latanoprost ophthalmic solution was instilled into both eyes. Plasma latanoprost acid concentrations were collected predose and 5, 15, 30, and 60 minutes after administration. MAIN OUTCOME MEASURES: Latanoprost acid plasma exposure. RESULTS: The evaluable PK analysis set included data from 39 of 47 enrolled subjects. The median peak plasma concentration value was higher in the <3-year age group (166 pg/ml) versus other groups (49, 16, and 26 pg/ml for the 3-<12-year, 12-<18-year, and ≥18-year age groups, respectively). The median area under the concentration-time curve from zero to last measurable concentration value was also higher in the <3-year age group (2716 pg/min/ml) versus other groups (588, 106, and 380 pg/min/ml for the 3-<12-year, 12-<18-year, and ≥18-year age groups, respectively). Latanoprost acid was rapidly eliminated from the blood, with plasma concentrations undetectable within 10 to 30 minutes postdose in all but the <3-year age group. There were no discontinuations or dose reductions due to adverse events or treatment-emergent adverse events. CONCLUSIONS: Latanoprost acid systemic exposure was higher in younger children versus adolescents and adults, attributed primarily to lower body weight and smaller blood volume. Latanoprost acid was eliminated rapidly in all age groups and resulted in only a brief period of systemic exposure after once-daily dosing. Higher systemic exposure was not accompanied by adverse events, and on the basis of extrapolation of safety data from adults, this pilot study suggests an adequate safety margin for systemic adverse effects with use of the adult topical dose of latanoprost in pediatric patients. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosures may be found after the references.


Subject(s)
Antihypertensive Agents/pharmacokinetics , Glaucoma/metabolism , Hydrophthalmos/metabolism , Prostaglandins F, Synthetic/pharmacokinetics , Administration, Topical , Adolescent , Adult , Aged , Aged, 80 and over , Antihypertensive Agents/adverse effects , Biological Availability , Child , Child, Preschool , Female , Humans , Infant , Intraocular Pressure/drug effects , Latanoprost , Male , Middle Aged , Ocular Hypertension/metabolism , Ophthalmic Solutions/adverse effects , Ophthalmic Solutions/pharmacokinetics , Prospective Studies , Prostaglandins F, Synthetic/adverse effects , Tonometry, Ocular
10.
J Clin Endocrinol Metab ; 93(2): 550-6, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17986636

ABSTRACT

CONTEXT: 11beta-Hydroxysteroid dehydrogenase type 1 (11betaHSD1) is a promising target for the treatment of type 2 diabetes mellitus. 11betaHSD1 catalyzes the intracrine conversion of inactive cortisone to the active glucocorticoid cortisol. OBJECTIVE: Demonstrating inhibition of 11betaHSD1 is challenging because there is no accessible way to directly assess the enzyme activity in vivo. Thus, it was proposed to assess the enzyme activity, in an indirect fashion, using two biomarker methods: the prednisolone generation study (conversion of oral prednisone to prednisolone in plasma) and the ratio of cortisol and cortisone metabolites in urine. DESIGN: This was a phase 1, double-blind, placebo-controlled, randomized, multiple-dose study. SETTING: The study was conducted in a clinical research unit. PARTICIPANTS: Sixty healthy adult volunteers participated in the study. INTERVENTION: Oral doses of PF-00915275 (0.3-15 mg) and prednisone (10 mg) were administered during the study. MAIN OUTCOME MEASURES: Safety, tolerability, pharmacokinetics, and pharmacodynamics of PF-00915275, a selective 11betaHSD1 inhibitor, were measured. RESULTS: Overall, multiple oral doses of PF-00915275 were safe and well tolerated. After oral administration, PF-00915275 was rapidly absorbed, slowly eliminated, and generally displayed dose-proportional increases in exposure. At the 15-mg dose, mean exposure to prednisolone was reduced by 37%, and there was a dose-dependent fall in the 5alpha-tetrahydrocortisol + 5beta-tetrahydrocortisol to tetrahydrocortisone ratio with maximum inhibition of 26% after 14 d. The urinary free cortisol to urinary free cortisone ratio, an indicator of 11betaHSD2 inhibition, did not change. CONCLUSION: PF-00915275 was safe at all doses tested. The results of the prednisolone generation test and the urinary metabolite ratios confirm that PF-00915275 is a selective 11betaHSD1 inhibitor.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1/antagonists & inhibitors , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , Aminopyridines/pharmacokinetics , Diabetes Mellitus, Type 2/drug therapy , Enzyme Inhibitors/pharmacokinetics , Sulfonamides/pharmacokinetics , Administration, Oral , Adolescent , Adult , Aminopyridines/administration & dosage , Aminopyridines/adverse effects , Biomarkers/blood , Biomarkers/metabolism , Biomarkers/urine , Cortisone/metabolism , Cortisone/urine , Double-Blind Method , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/adverse effects , Female , Humans , Hydrocortisone/metabolism , Hydrocortisone/urine , Hypothalamo-Hypophyseal System/drug effects , Male , Middle Aged , Pituitary-Adrenal System/drug effects , Prednisolone/blood , Prednisone/pharmacology , Sulfonamides/administration & dosage , Sulfonamides/adverse effects
11.
J Clin Endocrinol Metab ; 92(3): 857-64, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17200165

ABSTRACT

CONTEXT: The pathophysiological importance of glucocorticoids (GCs) is exemplified by patients with Cushing's syndrome who develop hypertension, obesity, and insulin resistance. At a cellular level, availability of GCs to the glucocorticoid and mineralocorticoid receptors is controlled by the isoforms of 11beta-hydroxysteroid dehydrogenase (11beta-HSD). In liver and adipose tissue, 11beta-HSD1 converts endogenous, inactive cortisone to active cortisol but also catalyzes the bioactivation of the synthetic prednisone to prednisolone. OBJECTIVE: The objective of the study was to compare markers of 11beta-HSD1 activity and demonstrate that inhibition of 11beta-HSD1 activity limits glucocorticoid availability to adipose tissue. DESIGN AND SETTING: This was a clinical study. PATIENTS: Seven healthy male volunteers participated in the study. INTERVENTION: Intervention included carbenoxolone (CBX) single dose (100 mg) and 72 hr of continuous treatment (300 mg/d). MAIN OUTCOME MEASURES: Inhibition of 11beta-HSD1 was monitored using five different mechanistic biomarkers (serum cortisol and prednisolone generation, urinary corticosteroid metabolite analysis by gas chromatography/mass spectrometry, and adipose tissue microdialysis examining cortisol generation and glucocorticoid-mediated glycerol release). RESULTS: Each biomarker demonstrated reduced 11beta-HSD1 activity after CBX administration. After both a single dose and 72 hr of treatment with CBX, cortisol and prednisolone generation decreased as did the urinary tetrahydrocortisol+5alpha-tetrahydrocortisol to tetrahydrocortisone ratio. Using adipose tissue microdialysis, we observed decreased interstitial fluid cortisol availability with CBX treatment. Furthermore, a functional consequence of 11beta-HSD1 inhibition was observed, namely decreased prednisone-induced glycerol release into adipose tissue interstitial fluid indicative of inhibition of GC-mediated lipolysis. CONCLUSION: CBX is able to inhibit rapidly the generation of active GC in human adipose tissue. Importantly, limiting GC availability in vivo has functional consequences including decreased glycerol release.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , Adipose Tissue/metabolism , Glucocorticoids/metabolism , Lipolysis , Adipose Tissue/drug effects , Adult , Carbenoxolone/administration & dosage , Carbenoxolone/pharmacokinetics , Extracellular Fluid/chemistry , Glucocorticoids/pharmacology , Humans , Hydrocortisone/metabolism , Lipolysis/drug effects , Male , Prednisolone/metabolism , Serum/chemistry
12.
Clin Pharmacokinet ; 44(2): 211-20, 2005.
Article in English | MEDLINE | ID: mdl-15656699

ABSTRACT

BACKGROUND AND OBJECTIVE: Posaconazole is a potent, extended-spectrum triazole antifungal agent currently in clinical development for the treatment of invasive fungal infections. This study was conducted to compare the bioavailability and resulting serum concentrations of posaconazole 800 mg following administration of three different dose regimens to fasting adults. STUDY DESIGN: This was a randomised, open-label, three-way crossover study. METHODS: Subjects fasted 12 hours before and 48 hours after the administration of posaconazole oral suspension (800 mg) given as a single dose (regimen A), 400 mg every 12 hours (regimen B) or 200 mg every 6 hours (regimen C). Plasma posaconazole concentrations were determined for 48 hours after the initial dose and subjects completed a 1-week washout period between treatment regimens. A one-compartment oral model with first-order rate of absorption and first-order rate of elimination was fitted to the plasma concentration-time data. Differences in exposure were investigated by allowing the bioavailability fraction to vary among regimens. STUDY PARTICIPANTS: A total of 18 healthy men were enrolled in and completed the study. MAIN OUTCOME MEASURES AND RESULTS: Posaconazole relative bioavailability was estimated to be significantly different among regimens (p < 0.0001) and increased with the number of doses, such that regimen B/regimen A = 1.98 +/- 0.35, representing a 98% increase, and regimen C/regimen A = 3.20 +/- 0.69, or a 220% increase. With use of the one-compartment model, the population steady-state values for area under the concentration-time curve over 24 hours were predicted to be 3900, 7700 and 12 400 microg.h/L, with average plasma concentrations of 162, 320 and 517 microg/L for regimens A, B and C, respectively. CONCLUSION: These data suggest that divided daily dose administration (every 12 or 6 hours) significantly increases posaconazole exposure under fasted conditions.


Subject(s)
Fasting/metabolism , Triazoles/administration & dosage , Triazoles/pharmacokinetics , Administration, Oral , Adult , Biological Availability , Cross-Over Studies , Drug Administration Schedule , Humans , Male , Models, Biological , Triazoles/adverse effects
13.
Antimicrob Agents Chemother ; 48(9): 3543-51, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15328123

ABSTRACT

Posaconazole is a potent, broad-spectrum triazole antifungal agent currently in clinical development for the treatment of refractory invasive fungal infections. Eight healthy male subjects received a single 399-mg (81.7 microCi) oral dose of [(14)C]posaconazole after consuming a high-fat breakfast. Urine, feces, and blood samples were collected for up to 336 h postdose and assayed for total radioactivity; plasma and urine samples were also assayed for parent drug. Posaconazole was orally bioavailable, with a median maximum posaconazole concentration in plasma achieved by 10 h postdose. Thereafter, posaconazole was slowly eliminated, with a mean half-life of 20 h. The greatest peak in the radioactivity profile of pooled plasma extracts was due to posaconazole, with smaller peaks due to a monoglucuronide, a diglucuronide, and a smaller fragment of the molecule. The mean total amount of radioactivity recovered was 91.1%; the cumulative excretion of radioactivity in feces and in urine was 76.9 and 14.0% of the dose, respectively. Most of the fecal radioactivity was associated with posaconazole, which accounted for 66.3% of the administered dose; however, urine contained only trace amounts of unchanged posaconazole. The radioactivity profile of pooled urine extracts included two monoglucuronide conjugates and a diglucuronide conjugate of posaconazole. These observations suggest that oxidative (phase 1) metabolism by cytochrome P450 isoforms represents only a minor route of elimination for posaconazole, and therefore cytochrome P450-mediated drug interactions should have a limited potential to impact posaconazole pharmacokinetics.


Subject(s)
Antifungal Agents/pharmacokinetics , Triazoles/pharmacokinetics , Adult , Antifungal Agents/administration & dosage , Biotransformation , Chromatography, High Pressure Liquid , Feces/chemistry , Glucuronides/metabolism , Humans , Intestinal Absorption , Male , Mass Spectrometry , Spectrophotometry, Ultraviolet , Suspensions , Triazoles/administration & dosage
14.
Antimicrob Agents Chemother ; 48(3): 804-8, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14982768

ABSTRACT

Posaconazole is a potent broad-spectrum azole antifungal agent in clinical development for the treatment of invasive fungal infections. This study evaluated the potential for a pH-dependent pharmacokinetic interaction between posaconazole and an antacid (Mylanta), under fasting and nonfasting conditions. Twelve men completed this randomized, four-period crossover, single-dose study. Subjects received 200 mg of posaconazole following a 10-h fast, with 20 ml of Mylanta and a 10-h fast, with 20 ml of Mylanta and a high-fat breakfast, and with a high-fat breakfast alone. Antacid coadministration had no statistically significant effects on posaconazole bioavailability under fasting or nonfasting conditions. In the fasting state, antacid slightly increased the relative oral bioavailability of posaconazole by 15% (P = 0.296); in the nonfasting state, antacid decreased the relative bioavailability of posaconazole by 12% (P = 0.352). Food increased the relative oral bioavailability of posaconazole by 400% (P = 0.001). In conclusion, the effect of antacid on posaconazole exposure in the fasting or nonfasting state was small and is not considered clinically significant.


Subject(s)
Antacids/pharmacology , Antifungal Agents/pharmacokinetics , Fasting/metabolism , Triazoles/pharmacokinetics , Adolescent , Adult , Biological Availability , Drug Interactions , Female , Half-Life , Humans , Hydrogen-Ion Concentration , Male , Middle Aged
15.
Br J Clin Pharmacol ; 57(2): 218-22, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14748822

ABSTRACT

AIMS: This randomized, crossover, single-dose study evaluated the relative oral bioavailability of posaconazole suspension and coprecipitate tablet formulations. Additionally, the study determined whether systemic exposure to posaconazole was affected by prandial status or by the fat content of a meal. METHODS: This was a randomized, open-label, four-way crossover, single-dose study in 20 healthy men. Posaconazole pharmacokinetics were evaluated over 72 h following a single oral dose of posaconazole suspension (200 mg/5 ml) administered with a high-fat meal, a nonfat breakfast, or after a 10 h fast, or posaconazole tablets (2 x 100 mg) administered with a high-fat meal. RESULTS: The posaconazole suspension showed a significant increase in bioavailability compared with the tablet (increase in AUC(0,72 h) = 137% (90% confidence interval (CI) 119%, 156% and Cmax = 123% (90% CI 104%, 146%). The mean increases in AUC(0,72 h) and Cmax values were about 400% when administered with a high-fat meal compared with administration of the suspension in the fasting state (AUC(0,72 h) 90% CI 343%, 448%; Cmax 90% CI 352%, 493%). Administration of the suspension with a nonfat meal enhanced exposure, resulting in an increase in AUC(0,72 h) of 264% (90% CI 231%, 302%) and in Cmax of 296% (90% CI 250%, 350%) relative to the fasted state. CONCLUSIONS: The suspension formulation of posaconazole was associated with enhanced systemic exposure and increased relative bioavailability compared with the tablet. Food substantially enhanced the rate and extent of posaconazole absorption in healthy subjects.


Subject(s)
Antifungal Agents/pharmacokinetics , Food , Triazoles/pharmacokinetics , Administration, Oral , Adolescent , Adult , Antifungal Agents/blood , Biological Availability , Cross-Over Studies , Food-Drug Interactions , Humans , Male , Middle Aged , Tablets , Triazoles/blood
16.
Antimicrob Agents Chemother ; 47(9): 2788-95, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12936975

ABSTRACT

The pharmacokinetics, safety, and tolerability of posaconazole, an investigational triazole antifungal, were evaluated following the administration of rising single and multiple oral doses. A total of 103 healthy adults were enrolled in two phase I trials. Each study had a double-blind, placebo-controlled, parallel-group design with a rising single-dose (RSD) or rising multiple-dose (RMD) scheme. In the RSD study, subjects received single doses of posaconazole oral tablets (50 to 1200 mg) or placebo. In the RMD study, subjects received posaconazole oral tablets (50 to 400 mg) or placebo twice daily for 14 days. By using model-independent methods, the area under the plasma concentration-time curve and the maximum concentration in plasma were determined and used to assess dose proportionality. In the RSD study, the levels of posaconazole in plasma increased proportionally between the 50- and 800-mg dose range, with saturation of absorption occurring above 800 mg. Dose proportionality was also observed in the RMD study. In both studies, the apparent volume of distribution was large (range, 343 to 1341 liters) and the terminal-phase half-life was long (range, 25 to 31 h). Posaconazole was well tolerated at all dose levels, and the adverse events were not dose dependent. No clinically significant changes in clinical laboratory test values or electrocardiograms were observed. Following the administration of single and twice-daily rising doses, the level of posaconazole exposure increased in a dose-proportional manner. The long elimination-phase half-life of posaconazole supports once- or twice-daily dosing in clinical trials; however, additional studies are required to determine if further division of the dose will enhance exposure.


Subject(s)
Antifungal Agents/adverse effects , Antifungal Agents/pharmacokinetics , Triazoles/adverse effects , Triazoles/pharmacokinetics , Adolescent , Adult , Antifungal Agents/administration & dosage , Area Under Curve , Dose-Response Relationship, Drug , Double-Blind Method , Humans , Male , Triazoles/administration & dosage
17.
Diabetes Educ ; 28(5): 779-95, 2002.
Article in English | MEDLINE | ID: mdl-14625964

ABSTRACT

PURPOSE: This article proposes a model grounded in behavioral theory and empirical evidence for use when developing a program to prevent type 2 diabetes in high-risk minority youth. METHODS: The model is based on key concepts of 4 behavioral theories: the Health Belief Model, Social Learning Theory, the Theory of Planned Behavior, and the Ecological Model. Determinants of behavior to target for change are selected based on their theoretical link to behavior change, their success in changing behavior in past programs, and through thorough formative research in the target community. RESULTS: Diabetes prevention in children requires modifying a complex set of behavior patterns. Social norms and the environment are especially important in children in whom cognitive processes have not fully developed. Family and community involvement is essential for developing a health program and providing a supportive environment in which to change behavior and ongoing reinforcement to maintain behavior changes. CONCLUSIONS: Behavioral theory informs the selection of factors to target in a behavioral intervention. Special considerations apply when working with children. A program to target risk must be based in behavioral theory, supported by practical data, and tailored to the needs and beliefs of the target community.


Subject(s)
Diabetes Mellitus, Type 2/prevention & control , Health Behavior/ethnology , Health Education/methods , Minority Groups/education , Minority Groups/psychology , Models, Psychological , Adolescent , Attitude to Health/ethnology , Child , Community Participation , Diabetes Mellitus, Type 2/ethnology , Family/psychology , Health Knowledge, Attitudes, Practice , Humans , Life Style , Needs Assessment , Obesity/complications , Obesity/ethnology , Obesity/prevention & control , Primary Prevention/methods , Psychological Theory , Risk Reduction Behavior , Self Efficacy
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