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1.
J Clin Transl Sci ; 7(1): e104, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37250985

RESUMEN

Introduction: Clinical trials are a vital component of translational science, providing crucial information on the efficacy and safety of new interventions and forming the basis for regulatory approval and/or clinical adoption. At the same time, they are complex to design, conduct, monitor, and report successfully. Concerns over the last two decades about the quality of the design and the lack of completion and reporting of clinical trials, characterized as a lack of "informativeness," highlighted by the experience during the COVID-19 pandemic, have led to several initiatives to address the serious shortcomings of the United States clinical research enterprise. Methods and Results: Against this background, we detail the policies, procedures, and programs that we have developed in The Rockefeller University Center for Clinical and Translational Science (CCTS), supported by a Clinical and Translational Science Award (CTSA) program grant since 2006, to support the development, conduct, and reporting of informative clinical studies. Conclusions: We have focused on building a data-driven infrastructure to both assist individual investigators and bring translational science to each element of the clinical investigation process, with the goal of both generating new knowledge and accelerating the uptake of that knowledge into practice.

2.
Children (Basel) ; 9(12)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36553327

RESUMEN

Drugs administered to children in the United States fall into two broad categories: (1) those that have followed the US Food and Drug Administration (US-FDA) pediatric drug approval process and are marketed as finished dosage forms with pediatric labeling; and (2) all others, many of which are used "off-label". The use of most drug products in pediatrics is still off label, often requiring special preparation, packaging, and, in some cases, compounding into preparations. The latter category includes compounded preparations that incorporate either a US-FDA approved finished dosage form (e.g., a sterile solution, sterile powder, nonsterile capsules, oral solution, crushed tablets, etc.), or rely on bulk active pharmaceutical ingredients (APIs). Compounded preparations are prepared for individual patients in 503A pharmacies, or on a larger scale and not just for specific patients, in licensed 503B establishments. Critical gaps in the current drug approval process for finished dosage forms have created a proverbial "Gordian knot" that needs to be untangled thoughtfully to facilitate increased production and approval of vitally needed medications for pediatric patients. This opinion will describe current regulatory processes pertaining to pediatrics-only drug approval in the United States. Additionally, discussed are steps required for a product to acquire pediatric labeling. Gaps in regulatory approval pathways for both manufactured and compounded pediatric drugs will be identified, especially those that complicate and slow development and availability to patients. Finally, suggestions for regulatory modifications that may enhance pediatric product development strategies for both manufacturers and compounders are suggested.

3.
Physiol Biochem Zool ; 95(5): 438-463, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35947690

RESUMEN

Allometry predicts that the 12-17-g American water shrew (Sorex palustris)-the world's smallest mammalian diver-will have the highest diving metabolic rate coupled with the lowest total body oxygen storage capacity, skeletal muscle buffering capacity, and glycolytic potential of any endothermic diver. Consistent with expectations, and potentially owing to their low thermal inertia, water shrews had a significantly higher diving metabolic rate in 10°C water (8.77 mL O2 g-1 h-1) compared with 30°C water (6.57 mL O2 g-1 h-1). Unlike larger-bodied divers, muscle myoglobin contributed minimally (7.7%-12.4%) to total onboard O2 stores of juvenile and adult water shrews, respectively, but was offset by high blood O2 carrying capacities (26.4%-26.9% v/v). Diving was predominantly aerobic, as only 1.2%-2.3% of dives in 10°C and 30°C water, respectively, exceeded the calculated aerobic dive limits at these temperatures (10.8-14.4 s). The mean voluntary dive time of water shrews during 20-min trials in 3°C-30°C water was 5.0±0.1 s (N=25, n=1,628), with a mean maximum dive time of 10.1±0.4 s. However, the average dive duration (6.9±0.2 s, n=257) of radio-telemetered shrews exclusively foraging in a simulated riparian environment (3°C water) for 12-28 h suggests that mean (but not maximum) dive times of water shrews in the wild may be longer. Mean dive duration, duration of the longest dive, and total time in water all decreased significantly as water temperature declined, suggesting that shrews employed behavioral thermoregulation to defend against immersion hypothermia. Additionally, free-diving shrews in the 24-h trials consistently elevated core body temperature by ∼1°C immediately before initiating aquatic foraging bouts and ended these bouts when body temperature was still at or above normal resting levels (∼37.8°C). We suggest that this observed predive hyperthermia aids to heighten the impressive somatosensory physiology, and hence foraging efficiency, of this diminutive predator while submerged.


Asunto(s)
Buceo , Animales , Regulación de la Temperatura Corporal/fisiología , Buceo/fisiología , Consumo de Oxígeno/fisiología , Musarañas , Agua
4.
Pharmaceutics ; 14(5)2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35631618

RESUMEN

The purpose of this work was to evaluate the suitability of recent US Food and Drug Administration (US-FDA)-approved and marketed oral liquid, powder, or granule products for children in North America, to identify the next group of Active Pharmaceutical Ingredients (APIs) that have high potential for development as commercially available FDA-approved finished liquid dosage forms, and to propose lists of compounded nonsterile preparations (CNSPs) that should be developed as commercially available FDA-approved finished liquid dosage forms, as well as those that pharmacists should continue to compound extemporaneously. Through this identification and categorization process, the pharmaceutical industry, government, and professionals are encouraged to continue to work together to improve the likelihood that patients will receive high-quality standardized extemporaneously compounded CNSPs and US-FDA-approved products.

5.
Kidney360 ; 3(1): 113-121, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-35368563

RESUMEN

Background: Adolescent obesity, a risk factor for cardiorenal morbidity in adulthood, has reached epidemic proportions. Obesity-related glomerulopathy (ORG) has an early reversible stage of hyperfiltration. Age-appropriate formulae for eGFR, which are standardized to ideal body surface area (BSA) and provide assessment of kidney function in ml/min/1.73 m2, may underestimate prevalence of early ORG. We investigated whether adjusting eGFR to actual BSA more readily identifies early ORG. Methods: We studied a cohort of 22,417 young individuals, aged 12-21 years, from a New York metropolitan multi-institutional electronic health records clinical database. eGFR was calculated in two ways: BSA-standardized eGFR, and absolute eGFR. Hyperfiltration was defined above a threshold of 135 ml/min per 1.73 m2 or 135 ml/min, respectively. The prevalence of hyperfiltration according to each formula was assessed in parallel to creatinine clearance. Results: Serum creatinine values and hyperfiltration prevalence according to BSA-standardized eGFR were similar, 13%-15%, across body mass index (BMI) groups. The prevalence of hyperfiltration determined by absolute eGFR differed across BMI groups: underweight, 2%; normal weight, 6%; overweight, 17%; and obese, 31%. This trend paralleled the rise in creatinine clearance across BMI groups. Conclusions: Absolute eGFR more readily identifies early ORG than the currently used formulae, which are adjusted to a standardized BSA and are not representative of current population BMI measures. Using absolute eGFR in clinical practice and research may improve the ability to identify, intervene, and reverse early ORG, which has great importance with increasing obesity rates.


Asunto(s)
Obesidad Infantil , Adolescente , Adulto , Índice de Masa Corporal , Superficie Corporal , Niño , Creatinina , Femenino , Tasa de Filtración Glomerular , Humanos , Obesidad Infantil/epidemiología , Adulto Joven
6.
J Am Pharm Assoc (2003) ; 62(1): 42-48, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34511371

RESUMEN

OBJECTIVE: To describe the widespread use of compounded bioidentical hormone therapies (cBHT). To define the term clinical utility and present why there is insufficient evidence to support the overall clinical utility of cBHT products. To recommend actions that pharmacists and regulators can take to promote safer cBHT use. SUMMARY: Nationwide, millions of men and women use cBHT products. Use of these products appears to be increasing year-to-year, according to the limited data reported by the 503 A and 503 B pharmacies that formulate and dispense these products. Although use appears to be widespread, the safety, efficacy, and clinical utility of these products remains unproven. This commentary provides examples of what draws consumers to these products, comparative costs, and formulation challenges. Actions to promote the safe use of cBHT and approaches to begin the study of these products are provided. CONCLUSION: While significant progress was made via the Drug Supply Chain Security Act in 2013 to improve the safety of compounding practice in general, efforts to further improve the safety and transparency of cBHT dispensing and use must continue, at both the local and national level.


Asunto(s)
Hormonas , Farmacias , Composición de Medicamentos , Femenino , Humanos , Farmacéuticos
7.
J Clin Transl Sci ; 5(1): e165, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34733542

RESUMEN

The ability to effectively lead an interdisciplinary translational team is a crucial component of team science success. Most KL2 Clinical Scholars have been members of scientific teams, but few have been team science leaders. There is a dearth of literature and outcome measures of effective Team Science Leadership in clinical and translational research. We focused our curriculum to emphasize Team Science Leadership, developed a list of Team Science Leadership competencies for translational investigators using a modified Delphi method, and incorporated the competencies into a quantitative evaluation survey. The survey is completed on entry and annually thereafter by the Scholar; the Scholar's primary mentor and senior staff who educate and interact with the Scholar rate the Scholar at the end of each year. The program leaders and mentor review the results with each Scholar. The survey scales had high internal consistency and good factor structure. Overall ratings by mentors and senior staff were generally high, but ratings by Scholars tended to be lower, offering opportunities for discussion and career planning. Scholars rated the process favorably. A Team Science Leadership curriculum and periodic survey of attained competencies can inform individual career development and guide team science curriculum development.

8.
J Clin Transl Sci ; 5(1): e143, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34422323

RESUMEN

INTRODUCTION: Non-alcoholic fatty liver disease (NAFLD) is an increasing cause of chronic liver disease that accompanies obesity and the metabolic syndrome. Excess fructose consumption can initiate or exacerbate NAFLD in part due to a consequence of impaired hepatic fructose metabolism. Preclinical data emphasized that fructose-induced altered gut microbiome, increased gut permeability, and endotoxemia play an important role in NAFLD, but human studies are sparse. The present study aimed to determine if two weeks of excess fructose consumption significantly alters gut microbiota or permeability in humans. METHODS: We performed a pilot double-blind, cross-over, metabolic unit study in 10 subjects with obesity (body mass index [BMI] 30-40 mg/kg/m2). Each arm provided 75 grams of either fructose or glucose added to subjects' individual diets for 14 days, substituted isocalorically for complex carbohydrates, with a 19-day wash-out period between arms. Total fructose intake provided in the fructose arm of the study totaled a mean of 20.1% of calories. Outcome measures included fecal microbiota distribution, fecal metabolites, intestinal permeability, markers of endotoxemia, and plasma metabolites. RESULTS: Routine blood, uric acid, liver function, and lipid measurements were unaffected by the fructose intervention. The fecal microbiome (including Akkermansia muciniphilia), fecal metabolites, gut permeability, indices of endotoxemia, gut damage or inflammation, and plasma metabolites were essentially unchanged by either intervention. CONCLUSIONS: In contrast to rodent preclinical findings, excess fructose did not cause changes in the gut microbiome, metabolome, and permeability as well as endotoxemia in humans with obesity fed fructose for 14 days in amounts known to enhance NAFLD.

9.
Pharmaceutics ; 13(8)2021 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-34452220

RESUMEN

The coronavirus disease 2019 (COVID-19) is an unprecedented pandemic that has severely impacted global public health and the economy. Hydroxychloroquine administered orally to COVID-19 patients was ineffective, but its antiviral and anti-inflammatory actions were observed in vitro. The lack of efficacy in vivo could be due to the inefficiency of the oral route in attaining high drug concentration in the lungs. Delivering hydroxychloroquine by inhalation may be a promising alternative for direct targeting with minimal systemic exposure. This paper reports on the characterisation of isotonic, pH-neutral hydroxychloroquine sulphate (HCQS) solutions for nebulisation for COVID-19. They can be prepared, sterilised, and nebulised for testing as an investigational new drug for treating this infection. The 20, 50, and 100 mg/mL HCQS solutions were stable for at least 15 days without refrigeration when stored in darkness. They were atomised from Aerogen Solo Ultra vibrating mesh nebulisers (1 mL of each of the three concentrations and, in addition, 1.5 mL of 100 mg/mL) to form droplets having a median volumetric diameter of 4.3-5.2 µm, with about 50-60% of the aerosol by volume < 5 µm. The aerosol droplet size decreased (from 4.95 to 4.34 µm) with increasing drug concentration (from 20 to 100 mg/mL). As the drug concentration and liquid volume increased, the nebulisation duration increased from 3 to 11 min. The emitted doses ranged from 9.1 to 75.9 mg, depending on the concentration and volume nebulised. The HCQS solutions appear suitable for preclinical and clinical studies for potential COVID-19 treatment.

10.
J Clin Transl Sci ; 5(1): e108, 2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-34192062

RESUMEN

INTRODUCTION: In March 2020, academic medical center (AMC) pharmacies were compelled to implement practice changes in response to the COVID-19 pandemic. These changes were described by survey data collected by the Clinical and Translational Science Awards (CTSA) program which were interpreted by a multi-institutional team of AMC pharmacists and physician investigators. METHODS: The CTSA program surveyed 60 AMC pharmacy departments. The survey included event timing, impact on pharmacy services, and corrective actions taken. RESULTS: Almost all departments (98.4%) reported at least one disruption. Shortages of personal protective equipment (PPE) were common (91.5%) as were drug shortages (66.0%). To manage drug shortages, drug prioritization protocols were utilized, new drug supply vendors were identified (79.3%), and onsite compounding was initiated. PPE shortages were managed by incorporating the risk mitigation strategies recommended by FDA and others. Research pharmacists supported new clinical research initiatives at most institutions (84.0%), introduced use of virtual site visits, and shipped investigational drugs directly to patients. Some pharmacies formulated novel investigational products for clinical trial use. Those AMC pharmacies within networked health systems assisted partner rural and inner-city hospitals by sourcing commercial and investigational drugs to alleviate local disease outbreaks and shortages in underserved populations. Pharmacy-based vaccination practice was expanded to include a wider range of pediatric and adult vaccines. CONCLUSION: The COVID-19 pandemic radically altered hospital pharmacy practice. By adopting innovative methods and adapting to regulatory imperatives, pharmacies at CTSA sites played an extremely important role supporting continuity of care and collaborating on critical clinical research initiatives.

11.
J Am Assoc Nurse Pract ; 28(6): 304-10, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26496143

RESUMEN

PURPOSE: To investigate the impact nurse practitioners' (NPs) documented mortality risk assessments (MRAs) and advance care planning (ACP) discussions have on clinical outcomes for newly enrolled Medicare Advantage nursing home patients. METHODS: Data collection in this mixed-method study consisted of quantitative data from a convenience sample of NPs' MRAs and medical record reviews 6 months later, and qualitative data from two NP focus groups. Quantitative analyses include descriptive statistics, bivariate ANOVA, and logistic regression. The qualitative content analysis included an iterative process of rereading transcribed notes, identifying codes, themes and significant statements. CONCLUSIONS: MRAs prioritize ACP discussions with patients/families (p = .0258). Positive clinical outcomes following ACP discussions include more patients with a comfort goal of care (86% increase), fewer patients with a full-code status (26% reduction), and a reduction in hospitalizations (p = .025). NPs agreed that ACP discussions have a positive impact on patient outcomes including a "good death." IMPLICATIONS FOR PRACTICE: MRAs and ACP discussions are beneficial to achieving better outcomes and fewer hospitalizations. Opportunity exists to further develop policy changes focused on enhancing the NPs' role in MRAs and ACP discussions with nursing home patients and families.


Asunto(s)
Planificación Anticipada de Atención , Mortalidad/tendencias , Enfermeras Practicantes/organización & administración , Evaluación de Resultado en la Atención de Salud/métodos , Medición de Riesgo , Anciano , Anciano de 80 o más Años , Femenino , Grupos Focales , Humanos , Masculino , Persona de Mediana Edad , Casas de Salud , Encuestas y Cuestionarios
12.
PLoS One ; 10(5): e0127246, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26018967

RESUMEN

BACKGROUND: Neuroblastoma (NB) is the most common cancer in infancy and most frequent cause of death from extracranial solid tumors in children. Ornithine decarboxylase (ODC) expression is an independent indicator of poor prognosis in NB patients. This study investigated safety, response, pharmacokinetics, genetic and metabolic factors associated with ODC in a clinical trial of the ODC inhibitor difluoromethylornithine (DFMO) ± etoposide for patients with relapsed or refractory NB. METHODS AND FINDINGS: Twenty-one patients participated in a phase I study of daily oral DFMO alone for three weeks, followed by additional three-week cycles of DFMO plus daily oral etoposide. No dose limiting toxicities (DLTs) were identified in patients taking doses of DFMO between 500-1500 mg/m2 orally twice a day. DFMO pharmacokinetics, single nucleotide polymorphisms (SNPs) in the ODC gene and urinary levels of substrates for the tissue polyamine exporter were measured. Urinary polyamine levels varied among patients at baseline. Patients with the minor T-allele at rs2302616 of the ODC gene had higher baseline levels (p=0.02) of, and larger decreases in, total urinary polyamines during the first cycle of DFMO therapy (p=0.003) and had median progression free survival (PFS) that was over three times longer, compared to patients with the major G allele at this locus although this last result was not statistically significant (p=0.07). Six of 18 evaluable patients were progression free during the trial period with three patients continuing progression free at 663, 1559 and 1573 days after initiating treatment. Median progression-free survival was less among patients having increased urinary polyamines, especially diacetylspermine, although this result was not statistically significant (p=0.056). CONCLUSIONS: DFMO doses of 500-1500 mg/m2/day are safe and well tolerated in children with relapsed NB. Children with the minor T allele at rs2302616 of the ODC gene with relapsed or refractory NB had higher levels of urinary polyamine markers and responded better to therapy containing DFMO, compared to those with the major G allele at this locus. These findings suggest that this patient subset may display dependence on polyamines and be uniquely susceptible to therapies targeting this pathway. TRIAL REGISTRATION: Clinicaltrials.gov NCT#01059071.


Asunto(s)
Eflornitina/farmacología , Neuroblastoma/tratamiento farmacológico , Inhibidores de la Ornitina Descarboxilasa/farmacología , Fenotipo , Poliaminas/metabolismo , Adolescente , Niño , Preescolar , Eflornitina/efectos adversos , Eflornitina/farmacocinética , Eflornitina/uso terapéutico , Etopósido/efectos adversos , Etopósido/farmacología , Etopósido/uso terapéutico , Femenino , Humanos , Lactante , Masculino , Neuroblastoma/enzimología , Neuroblastoma/genética , Neuroblastoma/orina , Ornitina Descarboxilasa/metabolismo , Inhibidores de la Ornitina Descarboxilasa/efectos adversos , Inhibidores de la Ornitina Descarboxilasa/farmacocinética , Inhibidores de la Ornitina Descarboxilasa/uso terapéutico , Poliaminas/orina , Recurrencia , Seguridad , Resultado del Tratamiento
13.
Pharmacy (Basel) ; 3(4): 284-294, 2015 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-28975916

RESUMEN

The lack of commercially-available pediatric drug products and dosage forms is well-known. A group of clinicians and scientists with a common interest in pediatric drug development and medicines-use systems developed a practical framework for identifying a list of active pharmaceutical ingredients (APIs) with the greatest market potential for development to use in pediatric patients. Reliable and reproducible evidence-based drug formulations designed for use in pediatric patients are needed vitally, otherwise safe and consistent clinical practices and outcomes assessments will continue to be difficult to ascertain. Identification of a prioritized list of candidate APIs for oral formulation using the described algorithm provides a broader integrated clinical, scientific, regulatory, and market basis to allow for more reliable dosage forms and safer, effective medicines use in children of all ages. Group members derived a list of candidate API molecules by factoring in a number of pharmacotherapeutic, scientific, manufacturing, and regulatory variables into the selection algorithm that were absent in other rubrics. These additions will assist in identifying and categorizing prime API candidates suitable for oral formulation development. Moreover, the developed algorithm aids in prioritizing useful APIs with finished oral liquid dosage forms available from other countries with direct importation opportunities to North America and beyond.

14.
J Prosthet Dent ; 110(5): 420-3, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23998623

RESUMEN

STATEMENT OF PROBLEM: The accuracy and efficiency of digital implant impressions should match conventional impressions. Comparisons should be made with clinically relevant data. PURPOSE: The purpose of this study was to evaluate the difficulty level and operator's perception between dental students and experienced clinicians when making digital and conventional implant impressions. MATERIAL AND METHODS: Thirty experienced dental professionals and 30 second-year dental students made conventional and digital impressions of a single implant model. A visual analog scale (VAS) and multiple-choice questionnaires were used to assess the participant's perception of difficulty, preference, and effectiveness. Wilcoxon signed-rank test within the groups and Wilcoxon rank-sum test between the groups were used for statistical analysis (α=.05). RESULTS: On a 0 to 100 VAS, the student group scored a mean difficulty level of 43.1 (±18.5) for the conventional impression technique and 30.6 (±17.6) for the digital impression technique (P=.006). The clinician group scored a mean (standard deviation) difficulty level of 30.9 (±19.6) for conventional impressions and 36.5 (±20.6) for digital impressions (P=.280). Comparison between groups showed a mean difficulty level with the conventional impression technique significantly higher in the student group (P=.030). The digital impression was not significantly different between the groups (P=.228). Sixty percent of the students preferred the digital impression and 7% the conventional impression; 33% expressed no preference. In the clinician group, 33% preferred the digital impression and 37% the conventional impression; 30% had no preference. Seventy-seven percent of the student group felt most effective with digital impressions, 10% with conventional impressions, and 13% with either technique, whereas 40% of the clinician group chose the digital impression as the most effective technique, 53% the conventional impression, and 7% either technique. CONCLUSIONS: The conventional impression was more difficult to perform for the student group than the clinician group; however, the difficulty level of the digital impression was the same in both groups. It was also determined that the student group preferred the digital impression as the most efficient impression technique, and the clinician group had an even distribution in the choice of preferred and efficient impression techniques.


Asunto(s)
Actitud del Personal de Salud , Diseño Asistido por Computadora , Implantes Dentales , Técnica de Impresión Dental , Odontólogos/psicología , Estudiantes de Odontología/psicología , Alginatos/química , Estudios de Cohortes , Diseño Asistido por Computadora/estadística & datos numéricos , Materiales de Impresión Dental/química , Técnica de Impresión Dental/estadística & datos numéricos , Eficiencia , Humanos , Satisfacción Personal , Polivinilos/química , Siloxanos/química , Encuestas y Cuestionarios , Interfaz Usuario-Computador , Escala Visual Analógica
15.
Cardiovasc Ther ; 31(2): 92-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21884028

RESUMEN

AIMS: Erythropoietin stimulating agents (ESAs) is an active area of clinical investigation in heart failure (HF) but can cause hypertension and higher hemoglobin concentrations (Hb) that have been associated with adverse outcomes. We evaluated a dosing algorithm and potential confounders' effect on Hb and blood pressure (BP) in a clinical trial. METHODS: In an ongoing randomized, placebo controlled, single blind clinical trial of ESA (epoetin alfa) in anemic patients with HF and a preserved ejection fraction (HFPEF), Hb was measured weekly as was BP, weight and concomitant medical therapy. A repeated measure mixed model evaluated determinants of weekly changes in Hb and BP. RESULTS: Among 45 subjects (78 ± 11 years, 67% women, EF = 57 ± 9%) with a total of 780 repeated weekly Hb measures, Hb significantly increased over time in those assigned to ESA (ß = 0.933, P < 0.0001), compared to placebo. Dose (ß = -0.108, P < 0.0001), patient weight (ß = -0.016, P = 0.0037), diuretic use (ß = -0.124, P = 0.0389), and time (ß = 0.003, P = 0.0331), were all significantly associated with Hb change. Increased diuretic dose and weight change were significantly inversely associated with changes in Hb. ESA administration and dose were not significant determinants of absolute BP or changes in BP from baseline. DISCUSSION: In addition to ESA dose and duration of therapy, factors indicative of volume status including weight and diuretic use are determinants of hemoglobin levels in HF subjects. CONCLUSION: The currently employed dosing algorithm, which adjusts the administration of ESA based on the absolute hemoglobin and weekly change in hemoglobin increases Hb with relatively a low weekly dose of ESA without significant effects on BP.


Asunto(s)
Algoritmos , Anemia/tratamiento farmacológico , Cálculo de Dosificación de Drogas , Eritropoyetina/administración & dosificación , Insuficiencia Cardíaca/fisiopatología , Hematínicos/administración & dosificación , Volumen Sistólico , Anciano , Anciano de 80 o más Años , Anemia/sangre , Anemia/complicaciones , Anemia/diagnóstico , Biomarcadores/sangre , Presión Sanguínea/efectos de los fármacos , Volumen Sanguíneo/efectos de los fármacos , Factores de Confusión Epidemiológicos , Diuréticos/uso terapéutico , Esquema de Medicación , Epoetina alfa , Eritropoyetina/efectos adversos , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Hematínicos/efectos adversos , Hemoglobinas/metabolismo , Humanos , Masculino , Análisis Multivariante , Ciudad de Nueva York , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Método Simple Ciego , Factores de Tiempo , Resultado del Tratamiento
16.
Clin Trials ; 8(4): 398-407, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21737464

RESUMEN

BACKGROUND: TNK-S2B, an innovative, randomized, seamless phase II/III trial of tenecteplase versus rt-PA for acute ischemic stroke, terminated for slow enrollment before regulatory approval of use of phase II patients in phase III. PURPOSE: (1) To review the trial design and comprehensive type I error rate simulations and (2) to discuss issues raised during regulatory review, to facilitate future approval of similar designs. METHODS: In phase II, an early (24-h) outcome and adaptive sequential procedure selected one of three tenecteplase doses for phase III comparison with rt-PA. Decision rules comparing this dose to rt-PA would cause stopping for futility at phase II end, or continuation to phase III. Phase III incorporated two co-primary hypotheses, allowing for a treatment effect at either end of the trichotomized Rankin scale. Assuming no early termination, four interim analyses and one final analysis of 1908 patients provided an experiment-wise type I error rate of <0.05. RESULTS: Over 1,000 distribution scenarios, each involving 40,000 replications, the maximum type I error in phase III was 0.038. Inflation from the dose selection was more than offset by the one-half continuity correction in the test statistics. Inflation from repeated interim analyses was more than offset by the reduction from the clinical stopping rules for futility at the first interim analysis. LIMITATIONS: Design complexity and evolving regulatory requirements lengthened the review process. CONCLUSIONS: (1) The design was innovative and efficient. Per protocol, type I error was well controlled for the co-primary phase III hypothesis tests, and experiment-wise. (2a) Time must be allowed for communications with regulatory reviewers from first design stages. (2b) Adequate type I error control must be demonstrated. (2c) Greater clarity is needed on (i) whether this includes demonstration of type I error control if the protocol is violated and (ii) whether simulations of type I error control are acceptable. (2d) Regulatory agency concerns that protocols for futility stopping may not be followed may be allayed by submitting interim analysis results to them as these analyses occur.


Asunto(s)
Ensayos Clínicos Fase II como Asunto/estadística & datos numéricos , Ensayos Clínicos Fase III como Asunto/estadística & datos numéricos , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/uso terapéutico , Enfermedad Aguda , Ensayos Clínicos Fase II como Asunto/métodos , Ensayos Clínicos Fase III como Asunto/métodos , Simulación por Computador , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Aprobación de Drogas , Terminación Anticipada de los Ensayos Clínicos , Fibrinolíticos/administración & dosificación , Humanos , Estudios Multicéntricos como Asunto/métodos , Estudios Multicéntricos como Asunto/estadística & datos numéricos , Selección de Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Proyectos de Investigación , Sesgo de Selección , Tenecteplasa , Activador de Tejido Plasminógeno/administración & dosificación
17.
Bioanalysis ; 2(8): 1501-13, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21083350

RESUMEN

BACKGROUND: Dried blood spots (DBS) sampling is a well-known technology for qualitative determination such as DNA analysis and screening of newborn metabolic disorders. The scientific community has recently expressed interest in applying the DBS technique for quantitative determination of drugs in biological fluid. RESULTS: Two new bioanalytical assays were developed and validated for the determination of naproxen in human plasma and in DBS samples using liquid chromatography coupled with tandem MS. Furthermore, plasma and DBS clinical samples were collected from four subjects enrolled as part of a bioequivalence study. Concentration data for plasma and DBS samples were determined and pharmacokinetic (PK) profiles in plasma and in DBS samples were compared. CONCLUSIONS: A strong correlation between PK data obtained by the DBS and conventional plasma method was observed, which makes DBS a valuable technique for further naproxen bioavailability and PK investigations and studies.


Asunto(s)
Análisis Químico de la Sangre/métodos , Recolección de Muestras de Sangre/métodos , Naproxeno/sangre , Naproxeno/farmacocinética , Análisis Químico de la Sangre/normas , Proteínas Sanguíneas/química , Recolección de Muestras de Sangre/instrumentación , Precipitación Química , Cromatografía Liquida , Ensayos Clínicos Controlados como Asunto , Desecación , Estabilidad de Medicamentos , Femenino , Humanos , Modelos Lineales , Masculino , Naproxeno/administración & dosificación , Naproxeno/metabolismo , Estándares de Referencia , Análisis de Regresión , Reproducibilidad de los Resultados , Solubilidad , Espectrometría de Masas en Tándem
18.
Am J Physiol Cell Physiol ; 299(1): C97-110, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20375277

RESUMEN

While heparin has been used almost exclusively as a blood anticoagulant, important literature demonstrates that it also has broad anti-inflammatory activity. Herein, using low anti-coagulant 2-O,3-O-desulfated heparin (ODSH), we demonstrate that most of the anti-inflammatory pharmacology of heparin is unrelated to anticoagulant activity. ODSH has low affinity for anti-thrombin III, low anti-Xa, and anti-IIa anticoagulant activities and does not activate Hageman factor (factor XII). Unlike heparin, ODSH does not interact with heparin-platelet factor-4 antibodies present in patients with heparin-induced thrombocytopenia and even suppresses platelet activation in the presence of activating concentrations of heparin. Like heparin, ODSH inhibits complement activation, binding to the leukocyte adhesion molecule P-selectin, and the leukocyte cationic granular proteins azurocidin, human leukocyte elastase, and cathepsin G. In addition, ODSH and heparin disrupt Mac-1 (CD11b/CD18)-mediated leukocyte adhesion to the receptor for advanced glycation end products (RAGE) and inhibit ligation of RAGE by its many proinflammatory ligands, including the advanced glycation end-product carboxymethyl lysine-bovine serum albumin, the nuclear protein high mobility group box protein-1 (HMGB-1), and S100 calgranulins. In mice, ODSH is more effective than heparin in reducing selectin-mediated lung metastasis from melanoma and inhibits RAGE-mediated airway inflammation from intratracheal HMGB-1. In humans, 50% inhibitory concentrations of ODSH for these anti-inflammatory activities can be achieved in the blood without anticoagulation. These results demonstrate that the anticoagulant activity of heparin is distinct from its anti-inflammatory actions and indicate that 2-O and 3-O sulfate groups can be removed to reduce anticoagulant activity of heparin without impairing its anti-inflammatory pharmacology.


Asunto(s)
Antiinflamatorios/farmacología , Anticoagulantes/farmacología , Coagulación Sanguínea/efectos de los fármacos , Heparina/análogos & derivados , Neumonía/tratamiento farmacológico , Receptores Inmunológicos/metabolismo , Trombocitopenia/prevención & control , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/efectos adversos , Antiinflamatorios/farmacocinética , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/farmacocinética , Antitrombina III/metabolismo , Pruebas de Coagulación Sanguínea , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Factor XIIa/metabolismo , Femenino , Productos Finales de Glicación Avanzada/metabolismo , Proteína HMGB1/metabolismo , Heparina/administración & dosificación , Heparina/efectos adversos , Heparina/farmacocinética , Heparina/farmacología , Humanos , Infusiones Intravenosas , Inyecciones Intravenosas , Inyecciones Subcutáneas , Ligandos , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Antígeno de Macrófago-1/metabolismo , Masculino , Melanoma Experimental/sangre , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Factores de Crecimiento Nervioso/metabolismo , Selectina-P/metabolismo , Activación Plaquetaria/efectos de los fármacos , Pruebas de Función Plaquetaria , Neumonía/sangre , Neumonía/inducido químicamente , Receptor para Productos Finales de Glicación Avanzada , Proteínas Recombinantes/metabolismo , Subunidad beta de la Proteína de Unión al Calcio S100 , Proteínas S100/metabolismo , Trombocitopenia/sangre , Trombocitopenia/inducido químicamente , Células U937
19.
Biochemistry ; 49(1): 226-35, 2010 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-19950984

RESUMEN

Brostallicin is a novel and unique glutathione transferase-activated pro-drug with promising anticancer activity, currently in phase I and II clinical evaluation. In this work, we show that, in comparison with the parental cell line showing low GST levels, the cytotoxic activity of brostallicin is significantly enhanced in the human breast carcinoma MCF-7 cell line, transfected with either human GST-pi or GST-mu. Moreover, we describe in detail the interaction of brostallicin with GSH in the presence of GSTP1-1 and GSTM2-2, the predominant GST isoenzymes found within tumor cells. The experiments reported here indicate that brostallicin binds reversibly to both isoenzymes with K(d) values in the micromolar range (the affinity being higher for GSTM2-2). Direct evidence that both GSTP1-1 and GSTM2-2 isoenzymes catalyze the Michael addition reaction of GSH to brostallicin has been obtained both by an HPLC-MS technique and by a new fluorometric assay. We also saw the rapid formation of an intermediate reactive species, which is slowly converted into the final products. This intermediate, identified as the alpha-chloroamido derivative of the GSH-brostallicin adduct, is able to alkylate DNA in a sequence-specific manner and appears to be the active form of the drug. The kinetic behavior of the reaction between brostallicin and GSH, catalyzed by GSTP1-1, has been studied in detail, and a minimum kinetic scheme that suitably describes the experimental data is provided. Overall, these data fully support and extend the findings that brostallicin could be indicated for the treatment of tumor overexpressing the pi or mu class GST.


Asunto(s)
Antineoplásicos/farmacología , Gutatión-S-Transferasa pi/metabolismo , Glutatión Transferasa/metabolismo , Guanidinas/farmacología , Pirroles/farmacología , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/metabolismo , Catálisis , Línea Celular Tumoral , ADN/metabolismo , Femenino , Gutatión-S-Transferasa pi/antagonistas & inhibidores , Glutatión Transferasa/antagonistas & inhibidores , Humanos , Cinética
20.
Cerebrovasc Dis ; 28(3): 266-75, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19609078

RESUMEN

BACKGROUND: Hydroxymethylglutaryl coenzyme A reductase inhibitors ('statins') reduce the neuronal injury in dose-dependent fashion in rodent stroke models. We sought to determine whether lovastatin at doses above those currently approved can be administered safely within 24 h after an acute ischemic stroke. METHODS: We conducted a phase 1B dose-finding study using an adaptive design novel to stroke trials, the continual reassessment method, to find the highest tolerated dose of lovastatin. Planned doses were 1, 3, 6, 8 and 10 mg/kg/day for 3 days. The primary safety outcomes were myotoxicity and hepatotoxicity. The model was calibrated to select a dose causing 7-13% toxicity. RESULTS: We enrolled 33 patients (16 men/17 women, age range 23-82 years). Three patients were treated at 1 mg/kg, 10 at 3 mg/kg, 12 at 6 mg/kg, and 8 at 8 mg/kg. Thirty of the 33 patients (90.9%) completed at least 11 of 12 doses. Two patients at the 6-mg/kg dose level experienced transient mild elevations in transaminases without clinical sequelae. After an initial dose reduction, the dose was re-escalated to 8 mg/kg, and no further patients reached safety outcomes. No clinical liver disease, myopathy, or creatine phosphokinase elevations occurred. The final model-based toxicity at 8 mg/kg was 13%; no patient was treated at 10 mg/kg. CONCLUSIONS: Lovastatin at doses above those currently approved by the Food and Drug Administration is feasible for 3 days after an acute ischemic stroke and the maximum tolerated dose is estimated to be 8 mg/kg/day. Further randomized studies are warranted to confirm its safety and to demonstrate its efficacy in improving functional outcomes after stroke.


Asunto(s)
Isquemia Encefálica/complicaciones , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Lovastatina/uso terapéutico , Fármacos Neuroprotectores , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/etiología , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Determinación de Punto Final , Etnicidad , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Pruebas de Función Hepática , Lovastatina/administración & dosificación , Lovastatina/efectos adversos , Masculino , Persona de Mediana Edad , Agregación Plaquetaria/efectos de los fármacos , Pruebas de Función Plaquetaria , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Recuperación de la Función , Accidente Cerebrovascular/clasificación , Adulto Joven
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