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1.
Nat Med ; 30(4): 1096-1103, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38622249

RESUMEN

Prasinezumab, a monoclonal antibody that binds aggregated α-synuclein, is being investigated as a potential disease-modifying therapy in early-stage Parkinson's disease. Although in the PASADENA phase 2 study, the primary endpoint (Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) sum of Parts I + II + III) was not met, prasinezumab-treated individuals exhibited slower progression of motor signs than placebo-treated participants (MDS-UPDRS Part III). We report here an exploratory analysis assessing whether prasinezumab showed greater benefits on motor signs progression in prespecified subgroups with faster motor progression. Prasinezumab's potential effects on disease progression were assessed in four prespecified and six exploratory subpopulations of PASADENA: use of monoamine oxidase B inhibitors at baseline (yes versus no); Hoehn and Yahr stage (2 versus 1); rapid eye movement sleep behavior disorder (yes versus no); data-driven subphenotypes (diffuse malignant versus nondiffuse malignant); age at baseline (≥60 years versus <60 years); sex (male versus female); disease duration (>12 months versus <12 months); age at diagnosis (≥60 years versus <60 years); motor subphenotypes (akinetic-rigid versus tremor-dominant); and motor subphenotypes (postural instability gait dysfunction versus tremor-dominant). In these subpopulations, the effect of prasinezumab on slowing motor signs progression (MDS-UPDRS Part III) was greater in the rapidly progressing subpopulations (for example, participants who were diffuse malignant or taking monoamine oxidase B inhibitors at baseline). This exploratory analysis suggests that, in a trial of 1-year duration, prasinezumab might reduce motor progression to a greater extent in individuals with more rapidly progressing Parkinson's disease. However, because this was a post hoc analysis, additional randomized clinical trials are needed to validate these findings.


Asunto(s)
Enfermedad de Parkinson , Humanos , Masculino , Femenino , Persona de Mediana Edad , Temblor/tratamiento farmacológico , Antiparkinsonianos/uso terapéutico , Monoaminooxidasa/uso terapéutico , Progresión de la Enfermedad
2.
Front Aging Neurosci ; 15: 1232387, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37810617

RESUMEN

Introduction: To test drugs with the potential to prevent the onset of Parkinson's disease (PD), it is key to identify individuals in the general population at high risk of developing PD. This is often difficult because most of the clinical markers are non-specific, common in PD but also common in older adults (e.g., sleep problems). Objective: We aimed to identify the clinical markers at high specificity for developing PD by comparing individuals with PD or prodromal PD to healthy controls. Methods: We investigated motor and non-motor symptoms (Movement Disorder Society Unified Parkinson's Disease Rating Scale Part 1 and 2 items) in 64 prodromal PD and 422 PD individuals calculating the odds ratios, adjusting for age and gender, for PD and prodromal PD versus 195 healthy controls. Symptoms at high specificity were defined as having an adjusted odds ratio ≥ 6. Results: Constipation had an adjusted odds ratio, 6.14 [95% CI: 2.94-12.80] showing high specificity for prodromal PD, and speech difficulties had an adjusted odds ratio, 9.61 [95% CI: 7.88-48.81] showing high specificity for PD. The proportion of participants showing these specific markers was moderate (e.g., prevalence of constipation was 43.75% in prodromal PD, and speech difficulties was 33.89% in PD), suggesting these symptoms may make robust predictors of prodromal PD and PD, respectively. Discussion: Clinical markers at high specificity for developing PD could be used as tools in the screening of general populations to identify individuals at higher risk of developing PD.

3.
N Engl J Med ; 387(5): 421-432, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35921451

RESUMEN

BACKGROUND: Aggregated α-synuclein plays an important role in the pathogenesis of Parkinson's disease. The monoclonal antibody prasinezumab, directed at aggregated α-synuclein, is being studied for its effect on Parkinson's disease. METHODS: In this phase 2 trial, we randomly assigned participants with early-stage Parkinson's disease in a 1:1:1 ratio to receive intravenous placebo or prasinezumab at a dose of 1500 mg or 4500 mg every 4 weeks for 52 weeks. The primary end point was the change from baseline to week 52 in the sum of scores on parts I, II, and III of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 236, with higher scores indicating greater impairment). Secondary end points included the dopamine transporter levels in the putamen of the hemisphere ipsilateral to the clinically more affected side of the body, as measured by 123I-ioflupane single-photon-emission computed tomography (SPECT). RESULTS: A total of 316 participants were enrolled; 105 were assigned to receive placebo, 105 to receive 1500 mg of prasinezumab, and 106 to receive 4500 mg of prasinezumab. The baseline mean MDS-UPDRS scores were 32.0 in the placebo group, 31.5 in the 1500-mg group, and 30.8 in the 4500-mg group, and mean (±SE) changes from baseline to 52 weeks were 9.4±1.2 in the placebo group, 7.4±1.2 in the 1500-mg group (difference vs. placebo, -2.0; 80% confidence interval [CI], -4.2 to 0.2; P = 0.24), and 8.8±1.2 in the 4500-mg group (difference vs. placebo, -0.6; 80% CI, -2.8 to 1.6; P = 0.72). There was no substantial difference between the active-treatment groups and the placebo group in dopamine transporter levels on SPECT. The results for most clinical secondary end points were similar in the active-treatment groups and the placebo group. Serious adverse events occurred in 6.7% of the participants in the 1500-mg group and in 7.5% of those in the 4500-mg group; infusion reactions occurred in 19.0% and 34.0%, respectively. CONCLUSIONS: Prasinezumab therapy had no meaningful effect on global or imaging measures of Parkinson's disease progression as compared with placebo and was associated with infusion reactions. (Funded by F. Hoffmann-La Roche and Prothena Biosciences; PASADENA ClinicalTrials.gov number, NCT03100149.).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antiparkinsonianos , Enfermedad de Parkinson , alfa-Sinucleína , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antiparkinsonianos/uso terapéutico , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/uso terapéutico , Método Doble Ciego , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Resultado del Tratamiento , alfa-Sinucleína/antagonistas & inhibidores
4.
Clin Transl Allergy ; 12(7): e12176, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35846226

RESUMEN

Background: Lebrikizumab is a monoclonal antibody that modulates activity of interleukin-13. The Phase 3 ACOUSTICS study assessed lebrikizumab efficacy and safety in adolescents with uncontrolled asthma despite standard-of-care treatment. Methods: Adolescents (aged 12-17 years) with uncontrolled asthma, prebronchodilator forced expiratory volume in 1 s 40%-90% predicted, and stable background therapy were randomised 1:1:1 to receive lebrikizumab 125 or 37.5 mg or placebo subcutaneously once every 4 weeks. Primary efficacy endpoint was asthma exacerbation rate over 52 weeks. Results: Between August 2013 and July 2016, 579 patients were screened and 346 were randomised; 224 (65%) completed the study with 52 weeks of treatment. Lebrikizumab 125 mg (n = 116) reduced the exacerbation rate at 52 weeks versus placebo (n = 117; adjusted rate ratio [RR] 0.49 [95% CI 0.28-0.83]; 51% rate reduction). Lebrikizumab 37.5 mg (n = 113) was less effective at reducing exacerbations (RR 0.60 [95% CI 0.35-1.03]; 40% rate reduction). In patients with blood eosinophil counts ≥300 cells/µl, both lebrikizumab doses reduced exacerbations (125 mg: RR 0.44 [95% CI 0.21-0.89]; 37.5 mg: 0.42 [95% CI 0.19-0.93]). Treatment-emergent adverse events, serious adverse events, and adverse events leading to study discontinuation occurred in 155 (68%), 7 (3%), and 5 (2%) of 229 patients who received lebrikizumab (both 125 and 37.5 mg doses) and in 72 (62%), 4 (3%), and 1 (1%) of 117 who received placebo, respectively. No deaths occurred. Conclusion: Lebrikizumab 125 mg reduced asthma exacerbation rates in adolescents with uncontrolled asthma. However, the study was prematurely terminated (sponsor's decision) potentially limiting interpretation of results. Clinical trial registration: NCT01875003 (www.ClinicalTrials.gov).

5.
Front Neurosci ; 15: 765765, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34966256

RESUMEN

Currently, no treatments available for Parkinson's disease (PD) can slow PD progression. At the early stage of the disease, only a subset of individuals with PD progress quickly, while the majority have a slowly progressive form of the disease. In developing treatments that aim to slow PD progression, clinical trials aim to include individuals who are likely to progress faster, such that a treatment effect, if one exists, can be identified easier and earlier. The aim of the present study was to identify baseline predictors of clinical progression in early PD. We analyzed 12-month data acquired from the PASADENA trial Part 1 (NCT03100149, n = 76 participants who were allocated to the placebo arm and did not start symptomatic therapy) and the Parkinson's Progression Markers Initiative (PPMI) study (n = 139 demographically and clinically matched participants). By using ridge regression models including clinical characteristics, imaging, and non-imaging biomarkers, we found that Hoehn and Yahr stage and dopamine transporter single-photon emission computed tomography specific binding ratios (Dat-SPECT SBR) in putamen ipsilateral to the side of motor symptom onset predicted PD progression at the early stage of the disease. Further studies are needed to confirm the validity of these predictors to identify with high accuracy individuals with early PD with a faster progression phenotype.

6.
Front Neurol ; 12: 705407, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34659081

RESUMEN

Background: Currently available treatments for Parkinson's disease (PD) do not slow clinical progression nor target alpha-synuclein, a key protein associated with the disease. Objective: The study objective was to evaluate the efficacy and safety of prasinezumab, a humanized monoclonal antibody that binds aggregated alpha-synuclein, in individuals with early PD. Methods: The PASADENA study is a multicenter, randomized, double-blind, placebo-controlled treatment study. Individuals with early PD, recruited across the US and Europe, received monthly intravenous doses of prasinezumab (1,500 or 4,500 mg) or placebo for a 52-week period (Part 1), followed by a 52-week extension (Part 2) in which all participants received active treatment. Key inclusion criteria were: aged 40-80 years; Hoehn & Yahr (H&Y) Stage I or II; time from diagnosis ≤2 years; having bradykinesia plus one other cardinal sign of PD (e.g., resting tremor, rigidity); DAT-SPECT imaging consistent with PD; and either treatment naïve or on a stable monoamine oxidase B (MAO-B) inhibitor dose. Study design assumptions for sample size and study duration were built using a patient cohort from the Parkinson's Progression Marker Initiative (PPMI). In this report, baseline characteristics are compared between the treatment-naïve and MAO-B inhibitor-treated PASADENA cohorts and between the PASADENA and PPMI populations. Results: Of the 443 patients screened, 316 were enrolled into the PASADENA study between June 2017 and November 2018, with an average age of 59.9 years and 67.4% being male. Mean time from diagnosis at baseline was 10.11 months, with 75.3% in H&Y Stage II. Baseline motor and non-motor symptoms (assessed using Movement Disorder Society-Unified Parkinson's Disease Rating Scale [MDS-UPDRS]) were similar in severity between the MAO-B inhibitor-treated and treatment-naïve PASADENA cohorts (MDS-UPDRS sum of Parts I + II + III [standard deviation (SD)]; 30.21 [11.96], 32.10 [13.20], respectively). The overall PASADENA population (63.6% treatment naïve and 36.4% on MAO-B inhibitor) showed a similar severity in MDS-UPDRS scores (e.g., MDS-UPDRS sum of Parts I + II + III [SD]; 31.41 [12.78], 32.63 [13.04], respectively) to the PPMI cohort (all treatment naïve). Conclusions: The PASADENA study population is suitable to investigate the potential of prasinezumab to slow disease progression in individuals with early PD. Trial Registration: NCT03100149.

7.
Blood ; 135(12): 912-920, 2020 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-31978221

RESUMEN

Complement C5 inhibition is the standard of care (SoC) for patients with paroxysmal nocturnal hemoglobinuria (PNH) with significant clinical symptoms. Constant and complete suppression of the terminal complement pathway and the high serum concentration of C5 pose challenges to drug development that result in IV-only treatment options. Crovalimab, a sequential monoclonal antibody recycling technology antibody was engineered for extended self-administered subcutaneous dosing of small volumes in diseases amenable for C5 inhibition. A 3-part open-label adaptive phase 1/2 trial was conducted to assess safety, pharmacokinetics, pharmacodynamics, and exploratory efficacy in healthy volunteers (part 1), as well as in complement blockade-naive (part 2) and C5 inhibitor-treated (part 3) PNH patients. Twenty-nine patients were included in part 2 (n = 10) and part 3 (n = 19). Crovalimab concentrations exceeded the prespecified 100-µg/mL level and resulted in complete and sustained terminal complement pathway inhibition in treatment-naive and C5 inhibitor-pretreated PNH patients. Hemolytic activity and free C5 levels were suppressed below clinically relevant thresholds (liposome assay <10 U/mL and <50 ng/mL, respectively). Safety was consistent with the known profile of C5 inhibition. As expected, formation of drug-target-drug complexes was observed in all 19 patients switching to crovalimab, manifesting as transient mild or moderate vasculitic skin reactions in 2 of 19 participants. Both events resolved under continued treatment with crovalimab. Subcutaneous crovalimab (680 mg; 4 mL), administered once every 4 weeks, provides complete and sustained terminal complement pathway inhibition in patients with PNH, warranting further clinical development (ClinicalTrials.gov identifier, NCT03157635).


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Complemento C5/antagonistas & inhibidores , Inactivadores del Complemento/uso terapéutico , Hemoglobinuria Paroxística/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Monoclonales/farmacología , Biomarcadores , Complemento C5/inmunología , Inactivadores del Complemento/farmacología , Monitoreo de Drogas , Femenino , Hemoglobinuria Paroxística/sangre , Hemoglobinuria Paroxística/inmunología , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Resultado del Tratamiento
8.
Respir Med ; 134: 143-149, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29413502

RESUMEN

BACKGROUND: Asthma is a heterogeneous and complex disease in both its clinical course and response to treatment. IL-13 is central to Type 2 inflammation and contributes to many features of asthma. In a previous Phase 2 study, lebrikizumab, an anti-IL-13 monoclonal antibody, did not significantly improve FEV1 in mild-to-moderate asthma patients not receiving ICS therapy. This Phase 3 study was designed to further assess the efficacy and safety of lebrikizumab in adult patients with mild-to-moderate asthma treated with daily short-acting ß2-agonist therapy alone. METHODS: Adult patients with mild-to-moderate asthma were randomised to receive lebrikizumab 125 mg subcutaneously (SC), placebo SC, or montelukast 10 mg orally for 12 weeks, with an 8-week follow-up period. The primary efficacy endpoint was absolute change in pre-bronchodilator FEV1 from baseline at Week 12. FINDINGS: A total of 310 patients were randomised and dosed in the study. The mean absolute change in FEV1 from baseline at Week 12 was higher in the lebrikizumab-treated arm compared with placebo (150 mL versus 67 mL); however, this improvement did not achieve statistical significance (overall adjusted difference of 83 mL [95% CI: -3, 170]; p = .06). Montelukast did not improve FEV1 as compared with placebo. Lebrikizumab was generally safe and well tolerated during the study. INTERPRETATION: Lebrikizumab did not significantly improve FEV1 in mild-to-moderate asthma patients at a dose expected to inhibit the IL-13 pathway. Inhibiting IL-13 in this patient population was not sufficient to improve lung function. These data support the findings of a previous trial of lebrikizumab in patients not receiving ICS. CLINICAL TRIALS REGISTRY NUMBER: This trial was registered under NCT02104674 at http://www.clinicaltrials.gov.


Asunto(s)
Antiasmáticos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Asma/tratamiento farmacológico , Acetatos/uso terapéutico , Administración por Inhalación , Adulto , Antiasmáticos/administración & dosificación , Antiasmáticos/efectos adversos , Antiasmáticos/sangre , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/sangre , Asma/fisiopatología , Ciclopropanos , Método Doble Ciego , Femenino , Volumen Espiratorio Forzado/efectos de los fármacos , Glucocorticoides/administración & dosificación , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Quinolinas/uso terapéutico , Índice de Severidad de la Enfermedad , Sulfuros , Insuficiencia del Tratamiento , Resultado del Tratamiento
9.
Eur Heart J ; 35(27): 1792-800, 2014 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-24639426

RESUMEN

AIMS: The effects of cholesteryl ester transfer protein (CETP) inhibition on lipids, inflammation, and markers of high-density lipoprotein (HDL) function, following an acute coronary syndrome (ACS), are unknown. METHODS AND RESULTS: The dal-ACUTE study randomized 300 patients (1 : 1) to dalcetrapib 600 mg/day or placebo within 1 week of an ACS. The primary endpoint was per cent change in HDL-cholesterol (HDL-C) after 4 weeks. Secondary endpoints included apolipoprotein levels, markers of HDL function, and inflammation. Dalcetrapib treatment increased HDL-C and apolipoprotein A1 by 33.7 and 11.8%, respectively (both P < 0.001) and total cholesterol efflux by 9.5% (P = 0.003) after 4 weeks, principally via an increase in non-ATP-binding cassette transporter (ABC) A1-mediated efflux, without statistically significant changes in pre-ß1-HDL levels. The increase in total efflux with dalcetrapib correlated most strongly with increases in apolipoprotein A1 and HDL-C (r = 0.46 and 0.43, respectively) rather than the increase in pre-ß1-HDL (r = 0.32). Baseline and on-treatment ABCA1-mediated efflux correlated most strongly with pre-ß1-HDL levels; in contrast, non-ABCA1-mediated efflux correlated better with apolipoprotein A1 and HDL-C levels. CONCLUSIONS: High-density lipoprotein raised through CETP inhibition with dalcetrapib improves cholesterol efflux, principally via a non-ABCA1-mediated pathway. While HDL-C was increased by one-third, apolipoprotein A1 and total efflux were increased only by one-tenth, supporting the concept of dissociation between improvements in HDL function and HDL-C levels, which may be of relevance to ongoing trials and the development of therapeutic interventions targeting HDL.


Asunto(s)
Síndrome Coronario Agudo/tratamiento farmacológico , Anticolesterolemiantes/administración & dosificación , Proteínas de Transferencia de Ésteres de Colesterol/antagonistas & inhibidores , Compuestos de Sulfhidrilo/administración & dosificación , Transportador 1 de Casete de Unión a ATP/metabolismo , Amidas , Angina Inestable/tratamiento farmacológico , Apolipoproteínas/metabolismo , Biomarcadores/metabolismo , Proteína C-Reactiva/metabolismo , HDL-Colesterol/metabolismo , Método Doble Ciego , Esquema de Medicación , Ésteres , Femenino , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Lipoproteínas/metabolismo , Masculino , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico
10.
Clin Pharmacokinet ; 52(4): 255-65, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23400900

RESUMEN

BACKGROUND AND OBJECTIVE: Dalcetrapib, a cholesteryl ester transfer protein (CETP) modulator, is a thioester pro-drug that is rapidly hydrolysed to generate a pharmacologically active thiol. The thiol covalently binds to plasma proteins as mixed disulfides, extensively distributes into plasma lipoprotein fractions, and is principally cleared by metabolism, including extensive first-pass metabolism. Here we report two studies assessing the effects of hepatic and renal impairment on the pharmacokinetics of the thiol and its primary metabolites. METHODS: Adults with hepatic or renal impairment and healthy controls were recruited in two separate non-randomized, open-label studies. Eligible subjects were aged 18-70 years (hepatic impairment study) or 18-75 years (renal impairment study) with a body mass index 18-40 kg/m(2). Healthy controls were matched by age, bodyweight and sex. Each participant received a single 600 mg oral dose of dalcetrapib. Plasma and urine sampling was performed up to 3-4 days post-dalcetrapib administration for analysis of the pharmacokinetics of the thiol and its primary S-methyl and S-glucuronide metabolites. In the renal impairment study, CETP activity and mass, and lipid profiles were also assessed. RESULTS: Twenty-eight subjects were enrolled in the hepatic impairment study (mild or moderate hepatic impairment, n = 8 in each group; controls, n = 12). Thirty-five subjects participated in the renal impairment study (mild, moderate or severe renal impairment, n = 8 in each group; controls, n = 11). In patients with moderate hepatic impairment, the area under the plasma concentration-time curve from time zero to infinity (AUC(∞)) for thiol exposure was increased 34 % (geometric mean ratio [GMR] 1.34, 90 % CI 1.02-1.76), compared with matched controls. Regression analysis revealed a weak inverse relationship between thiol exposure and creatinine clearance (p = 0.0137, r(2) = 17.1 %). In patients with moderate or severe renal impairment, thiol exposures were 62 % (AUC(∞) GMR 1.62, 90 % CI 0.81-3.27) and 81 % (AUC(∞) GMR 1.81, 90 % CI 1.21-2.71) higher, respectively, than matched controls. Exposures of the S-glucuronide and S-methyl metabolites were also higher in hepatic and renal impairment groups. In the renal impairment study, CETP activity was decreased following administration of dalcetrapib, with no clear differences between groups. CONCLUSION: Hepatic and renal impairment both altered dalcetrapib pharmacokinetics and increased thiol exposure, with the extent of the effect dependent on the severity of impairment. The effect of renal impairment may be linked to altered distribution of the thiol, which illustrates the importance of assessing distribution to understand the causes and consequences of altered pharmacokinetics of thiol drugs in patient populations.


Asunto(s)
Anticolesterolemiantes/farmacocinética , Enfermedades Renales/metabolismo , Hepatopatías/metabolismo , Compuestos de Sulfhidrilo/farmacocinética , Adolescente , Adulto , Anciano , Amidas , Anticolesterolemiantes/efectos adversos , Anticolesterolemiantes/sangre , Anticolesterolemiantes/orina , Ésteres , Femenino , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Análisis de Regresión , Compuestos de Sulfhidrilo/efectos adversos , Compuestos de Sulfhidrilo/sangre , Compuestos de Sulfhidrilo/orina , Distribución Tisular , Adulto Joven
11.
Int J Clin Pharmacol Ther ; 51(3): 215-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23357838

RESUMEN

OBJECTIVE: To assess the effect of the UGT inhibitor probenecid on the pharmacokinetics of dalcetrapib, an investigational drug whose pharmacologically active thiol form undergoes glucuronidation (fm UGT ≥ 0.25). MATERIALS AND METHODS: A two-way crossover study in 20 healthy subjects. Subjects received a single 600 mg dose of dalcetrapib with or without probenecid (500 mg 4 times daily for 6 days). RESULTS: AUC∞ and Cmax of dalcetrapib thiol were increased by 14% and 21%, respectively, by co-administration of probenecid. CONCLUSIONS: This case study illustrates the difficulty in predicting clinically relevant drug-drug interactions for UGT substrates based only on the fraction metabolized by glucuronidation.


Asunto(s)
Anticolesterolemiantes/farmacocinética , Glucuronosiltransferasa/antagonistas & inhibidores , Probenecid/farmacología , Compuestos de Sulfhidrilo/farmacocinética , Adulto , Amidas , Área Bajo la Curva , Estudios Cruzados , Interacciones Farmacológicas , Ésteres , Femenino , Humanos , Masculino
12.
Res Synth Methods ; 4(4): 342-50, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26053947

RESUMEN

CONTEXT: Meta-analyses are regularly used to inform healthcare decisions. Concerns have been expressed about the quality of meta-analyses and, in particular, about those supported by the pharmaceutical industry. OBJECTIVE: The objective of this study is to compare the quality of pharmaceutical-industry-supported meta-analyses with academic meta-analyses and of meta-analyses published before and after companies started to disclose their data. DATA SOURCES: We identified industry-supported meta-analyses by searching the Scopus bibliographic database, using author affiliations. We matched each industry-supported meta-analysis with an academic meta-analysis using high-level MeSH terms in PubMed. STUDY SELECTION: We included meta-analyses of randomized trials assessing the efficacy or safety of any pharmaceutical intervention in humans, published in 2002-2004 or 2008-2009. Cochrane reviews were excluded. Two individuals independently selected papers, with discrepancies resolved by two further individuals. ASSESSMENT: We developed and piloted a quality-assessment tool, consisting of 43 questions in four domains, with a key summary question covering each domain. Two individuals independently assessed each meta-analysis. RESULTS: We examined 126 meta-analysis publications in 63 matched pairs. The average quality was low, with fewer than 50% adequate in three of the four domains. Industry-supported meta-analyses less often demonstrated adequate methods for locating studies and assessing their quality (odds ratio 0.44, 95% confidence interval 0.21 to 0.92), for analysing the included studies (0.52, 0.25 to 1.06), for undertaking meta-analyses (0.82, 0.40 to 1.68) and in reaching sound conclusions (0.62, 0.30 to 1.28). Quality generally improved over time, particularly for some aspects of industry reports. CONCLUSIONS: Academic meta-analysis papers are generally of higher quality than industry-supported ones. This is largely due to less detailed reporting in industry-supported meta-analyses and a tendency for them to take the included studies at face value, probably arising from the implicit assumption that these studies already have high methodological standards to meet licensing requirements. The improved quality over time does not appear to be due to the use of data disclosed by industry. The main limitations of this study are the small sample of papers and the subjective nature of some of the assessment processes.


Asunto(s)
Análisis por Apareamiento , Metaanálisis como Asunto , Academias e Institutos , Exactitud de los Datos , Industria Farmacéutica , Humanos , Modelos Estadísticos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Apoyo a la Investigación como Asunto
13.
Res Synth Methods ; 4(4): 351-66, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26053948

RESUMEN

BACKGROUND: Because meta-analyses are increasingly prevalent and cited in the medical literature, it is important that tools are available to assess their methodological quality. When performing an empirical study of the quality of published meta-analyses, we found that existing tools did not place a strong emphasis on statistical and interpretational issues. METHODS: We developed a quality-assessment tool using existing materials and expert judgment as a starting point, followed by multiple iterations of input from our working group, piloting, and discussion. After having used the tool for our empirical study, agreement for four key items in the tool was measured using weighted kappa coefficients. RESULTS: Our tool contained 43 items divided into four key areas (data sources, analysis of individual studies, meta-analysis methods, and interpretation), and each area ended with a summary question. We also produced guidance for completing the tool. Agreement between raters was fair to moderate. CONCLUSIONS: The tool should usefully inform subsequent initiatives to develop quality-assessment tools for meta-analysis. We advocate use of consensus between independent raters when assessing statistical appropriateness and adequacy of interpretation in meta-analyses.


Asunto(s)
Metaanálisis como Asunto , Sesgo , Bioestadística , Exactitud de los Datos , Humanos , Modelos Estadísticos
14.
Cochrane Database Syst Rev ; (7): CD002066, 2012 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-22786477

RESUMEN

BACKGROUND: Breathlessness is a common symptom in people with advanced disease. The most effective treatments are aimed at treating the underlying cause of the breathlessness but this may not be possible and symptomatic treatment is often necessary. Strategies for the symptomatic treatment of breathlessness have never been systematically evaluated. Opioids are commonly used to treat breathlessness: the mechanisms underlying their effectiveness are not completely clear and there have been few good-sized trials in this area. OBJECTIVES: To determine the effectiveness of opioid drugs given by any route in relieving the symptom of breathlessness in patients who are being treated palliatively. SEARCH METHODS: An electronic search was carried out of Medline, Embase, CINAHL, T he Cochrane L ibrary, Dissertation Abstracts, Cancercd and SIGLE. Review articles and reference lists of retrieved articles were hand searched. Date of most recent search: May 1999. SELECTION CRITERIA: Randomised double-blind, controlled trials comparing the use of any opioid drug against placebo for the relief of breathlessness were included. Patients with any illness suffering from breathlessness were included and the intervention was any opioid, given by any route, in any dose. DATA COLLECTION AND ANALYSIS: Studies identified by the search were imported into a reference manager database. The full texts of the relevant studies were retrieved and data were independently extracted by two review authors. Studies were quality scored according to the Oxford Quality scale. The primary outcome measure used was breathlessness and the secondary outcome measure was exercise tolerance. Studies were divided into non-nebulised and nebulised and were analysed both separately and together. A qualitative analysis was carried out of adverse effects of opioids. Where appropriate, meta-analysis was carried out. MAIN RESULTS: Eighteen studies were identified of which nine involved the non-nebulised route of administration and nine the nebulised route. A small but statistically significant positive effect of opioids was seen on breathlessness in the analysis of studies using non-nebulised opioids. There was no statistically significant positive effect seen for exercise tolerance in either group of studies or for breathlessness in the studies using nebulised opioids. AUTHORS' CONCLUSIONS: There is evidence to support the use of oral or parenteral opioids to palliate breathlessness although numbers of patients involved in the studies were small. No evidence was found to support the use of nebulised opioids. Further research with larger numbers of patients, using standardised protocols and with quality of life measures is needed.


Asunto(s)
Apnea/tratamiento farmacológico , Narcóticos/uso terapéutico , Cuidados Paliativos , Enfermo Terminal , Apnea/etiología , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
15.
Int J Clin Pharmacol Ther ; 50(4): 248-56, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22456295

RESUMEN

UNLABELLED: Dalcetrapib, a cholesteryl ester transfer protein modulator, under development to increase high-density lipoprotein cholesterol and potentially decrease cardiovascular risk, will potentially be co-prescribed to women on oral contraceptive (OC). OBJECTIVE: Assess the effect of dalcetrapib on the pharmacokinetics and ability to suppress ovulation of Microgynon® 30, a representative monophasic OC. MATERIALS AND METHODS: A single-center, randomized, open-label, two-period crossover study in healthy women receiving monophasic OC. Subjects received Microgynon® 30 (ethinylestradiol 0.03 mg/levonorgestrel 0.15 mg) once daily for 21 days followed by 7 treatment-free days (run-in period), then were randomized to Microgynon® 30 daily for 21 days with or without dalcetrapib 900 mg daily for Day 1 - 14. Plasma ethinylestradiol and levonorgestrel were measured on Day 14, and luteinizing hormone, follicle stimulating hormone, progesterone and estrogen from Day 11 - 14. The primary endpoint plasma exposure (AUC0-24 and Cmax) on Day 14 was evaluated for ethinylestradiol and levonorgestrel. Safety was monitored throughout. RESULTS: 30 subjects were randomized. The exposure of ethinylestradiol and levonorgestrel was similar when Microgynon® 30 was administered with or without dalcetrapib; for ethinylestradiol the geometric mean ratio %, (90% confidence interval (CI)) for AUC0-24 and Cmax were 92 (86 - 98) and 105 (95 - 115) and for levonorgestrel 92 (88 - 96) and 93 (87 - 99), respectively. Concentrations of luteinizing hormone, follicle stimulating hormone, estrogen and progesterone were comparable between treatments. CONCLUSIONS: Dalcetrapib has no clinically relevant effect on the pharmacokinetics of ethinylestradiol and levonorgestrel. Contraceptive efficacy of Microgynon® 30 is not anticipated to be compromised by co-administration of dalcetrapib.


Asunto(s)
Anticolesterolemiantes/administración & dosificación , Anticonceptivos Orales Combinados/administración & dosificación , Anticonceptivos Orales Combinados/farmacocinética , Etinilestradiol/administración & dosificación , Etinilestradiol/farmacocinética , Levonorgestrel/administración & dosificación , Levonorgestrel/farmacocinética , Inhibición de la Ovulación/efectos de los fármacos , Compuestos de Sulfhidrilo/administración & dosificación , Adulto , Amidas , Anticolesterolemiantes/efectos adversos , Biomarcadores/sangre , Anticonceptivos Orales Combinados/sangre , Estudios Cruzados , Combinación de Medicamentos , Interacciones Farmacológicas , Ésteres , Etinilestradiol/sangre , Femenino , Hormona Folículo Estimulante Humana/sangre , Humanos , Levonorgestrel/sangre , Hormona Luteinizante/sangre , Progesterona/sangre , Compuestos de Sulfhidrilo/efectos adversos , Adulto Joven
16.
Stat Med ; 30(25): 2967-85, 2011 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-21826697

RESUMEN

Meta-analyses of clinical trials with continuous outcome data typically report the effect of an intervention as either a mean difference or a standardized mean difference. These results can be difficult to interpret, and re-expressing the effect size in terms of risk may facilitate understanding and applicability. We describe three methods for obtaining risks in such situations. Two of these methods involve direct transformation of a standardized mean difference to an odds ratio. The third entails estimation of risks in the two groups for a specific cut point. We extend this third approach to a completed meta-analysis by expressing the finding in the format of a single 'meta-study'. We compare the methods in two examples of meta-analyses and in a series of simulation studies that examine their properties in individual studies and in meta-analyses. These simulations show that the methods for expressing meta-analysis results from continuous outcomes are sensitive to underlying distributions, sample sizes and cut points but are remarkably robust to the presence of heterogeneity across studies. We offer suggestions of situations in which the various methods may safely be applied. In particular, if the underlying distribution is approximately normal, then estimation of risks for a specific cut point may be used for large sample sizes; direct transformations may be preferable otherwise. However, if the standard deviations in the two groups are notably different, then none of the methods have good properties. Furthermore, absolute risks are safely estimated after direct transformation only if they are in the region of 20% to 80%.


Asunto(s)
Metaanálisis como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Riesgo , Trastornos de Ansiedad/terapia , Terapia Conductista , Simulación por Computador/estadística & datos numéricos , Interpretación Estadística de Datos , Demencia/tratamiento farmacológico , Humanos , Fármacos Neuroprotectores/uso terapéutico , Oportunidad Relativa , Fenilcarbamatos/uso terapéutico , Rivastigmina , Tamaño de la Muestra
17.
Clin Drug Investig ; 31(5): 325-35, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21366361

RESUMEN

BACKGROUND: Dalcetrapib is a modulator of cholesteryl ester transfer protein (CETP) activity developed to raise levels of high-density lipoprotein cholesterol (HDL-C) with the goal of further reduction of cardiovascular events additive to standard of care alone. In clinical studies, dalcetrapib has been shown to effectively increase levels of HDL-C with no significant safety concerns. OBJECTIVE: The primary objective was to investigate the safety of single ascending and multiple ascending doses of dalcetrapib at doses markedly greater than that intended therapeutically (600 mg/day). Secondary objectives were to investigate the pharmacokinetics/pharmacodynamics and dose proportionality of dalcetrapib. STUDY DESIGN: Randomized, double-blind, placebo-controlled, combined single and multiple ascending dose phase I study. Healthy males (age 18-65 years, body mass index 18-32 kg/m2) were randomized to four of five dalcetrapib doses (2100, 2700, 3300, 3900 or 4500 mg) or placebo, with ≥10 days washout between doses (n = 15, single ascending doses) or to dalcetrapib (1800, 2100, 3000 or 3900 mg once daily) or placebo for 7 days (four cohorts, each n = 10, randomization 8 : 2, multiple ascending doses). MAIN OUTCOME MEASURE: Tolerability and safety were assessed by monitoring adverse events (AEs), laboratory parameters, vital signs and 12-lead ECG recordings. Primary pharmacokinetic assessments were area under the plasma concentration-time curve (AUC) from time zero to infinity (AUC(∞)) and maximum observed plasma concentration (C(max)) [single doses] and AUC from time zero to 24 hours (AUC(24)) and C(max) (multiple doses). Pharmacodynamic assessments included CETP activity and lipids (multiple dosing only). RESULTS: Exposure increased with dose but was less than proportional to increasing dose after single dosing, although deviation from dose proportionality could not be demonstrated for C(max). Dose proportionality was consistent following multiple doses. Steady state was modelled to have been reached by approximately 4 days, with little to no accumulation. CETP activity reduction was dose dependent (maximum -55% after 3900 mg; placebo -2.6%) at 6 hours post-dose on day 1, while HDL-C increased by 12-19% (placebo -13%) on day 8 following treatment with 1800-3900 mg/day for 7 days. All AEs were mild or moderate in intensity and there were no serious AEs, deaths or withdrawals due to AEs. No clinically relevant effects on laboratory parameters, cardiac parameters or vital signs were noted. CONCLUSION: Single-dose dalcetrapib up to 4500 mg and multiple doses up to 3900 mg were generally safe and well tolerated.


Asunto(s)
Anticolesterolemiantes/administración & dosificación , Proteínas de Transferencia de Ésteres de Colesterol/antagonistas & inhibidores , Modelos Biológicos , Compuestos de Sulfhidrilo/administración & dosificación , Adolescente , Adulto , Anciano , Amidas , Anticolesterolemiantes/efectos adversos , Anticolesterolemiantes/farmacocinética , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Electrocardiografía , Ésteres , Humanos , Masculino , Persona de Mediana Edad , Compuestos de Sulfhidrilo/efectos adversos , Compuestos de Sulfhidrilo/farmacocinética , Factores de Tiempo , Adulto Joven
18.
Res Synth Methods ; 1(1): 66-80, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26056093

RESUMEN

Meta-analyses are fundamental tools for collating and synthesizing large amounts of information, and graphical displays have become the principal tool for presenting the results of multiple studies of the same research question. We review standard and proposed graphical displays for presentation of meta-analytic data, and offer our recommendations on how they might be presented to provide the most useful and user-friendly illustrations. We concentrate on graphs that specifically aim to present similar sorts of univariate results from multiple studies. We start with forest plots and funnel plots, and proceed to Galbraith (or radial) plots, L'Abbé (and related) plots, further plots useful for investigating heterogeneity, plots useful for model diagnostics and plots for illustrating likelihoods and Bayesian meta-analyses. Copyright © 2010 John Wiley & Sons, Ltd.

19.
Stat Med ; 27(29): 6072-92, 2008 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-18800342

RESUMEN

When literature-based meta-analyses involve outcomes with skewed distributions, the best available data can sometimes be a mixture of results presented on the raw scale and results presented on the logarithmic scale. We review and develop methods for transforming between these results for two-group studies, such as clinical trials and prospective or cross-sectional epidemiological studies. These allow meta-analyses to be conducted using all studies and on a common scale. The methods can also be used to produce a meta-analysis of ratios of geometric means when skewed data are reported on the raw scale for every study. We compare three methods, two of which have alternative standard error formulae, in an application and in a series of simulation studies. We conclude that an approach based on a log-normal assumption for the raw data is reasonably robust to different true distributions; and we provide new standard error approximations for this method. An assumption can be made that the standard deviations in the two groups are equal. This increases precision of the estimates, but if incorrect can lead to very misleading results.


Asunto(s)
Biometría/métodos , Metaanálisis como Asunto , Interpretación Estadística de Datos , Humanos , Modelos Lineales , Lipoproteína Lipasa/genética , Modelos Estadísticos , Epidemiología Molecular , Polimorfismo Genético , Triglicéridos/sangre
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