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1.
Int J Technol Assess Health Care ; 28(3): 278-84, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22980705

RESUMEN

OBJECTIVES: High-quality clinical evidence is most often lacking when novel high-risk devices enter the European market. At the same time, a randomized controlled trial (RCT) is often initiated as a requirement for obtaining market access in the US. Should coverage in Europe be postponed until RCT data are available? We studied the premarket clinical evaluation of innovative high-risk medical devices in Europe compared with the US, and with medicines, where appropriate. METHODS: The literature and regulatory documents were checked. Representatives from industry, Competent Authorities, Notified Bodies, Ethics Committees, and HTA agencies were consulted. We also discuss patient safety and the transparency of information. RESULTS: In contrast to the US, there is no requirement in Europe to demonstrate the clinical efficacy of high-risk devices in the premarket phase. Patients in Europe can thus have earlier access to a potentially lifesaving device, but at the risk of insufficiently documented efficacy and safety. Variations in the stringency of clinical reviews, both at the level of Notified Bodies and Competent Authorities, do not guarantee patient safety. We tried to document the design of premarket trials in Europe and number of patients exposed, but failed as this information is not made public. Furthermore, the Helsinki Declaration is not followed with respect to the registration and publication of premarket trials. CONCLUSIONS: For innovative high-risk devices, new EU legislation should require the premarket demonstration of clinical efficacy and safety, using an RCT if possible, and a transparent clinical review, preferably centralized.


Asunto(s)
Equipos y Suministros , Evaluación de la Tecnología Biomédica/métodos , Europa (Continente) , Medición de Riesgo , Encuestas y Cuestionarios , Evaluación de la Tecnología Biomédica/organización & administración
2.
Orphanet J Rare Dis ; 12(1): 88, 2017 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-28494776

RESUMEN

BACKGROUND: Inexpensive medicines with a long history of use may currently be prescribed off-label for rare indications. Reimbursement is at the discretion of health insurance companies, and may be unpredictable. The example addressed was ephedrine as add-on treatment for myasthenia gravis. Stakeholders from academia, a patient organization, the Dutch National Health Care Institute (NHCI) and Dutch Medicines Evaluation Board (MEB) advised on the trial design. The NHCI and MEB agreed to provide scientific advice on the suitability of the evidence generated by the trial, for regulatory decisions. This paper describes the feasibility of the trial and the utility of its aggregated results. RESULTS: The trialists experienced the trial as feasible. Retrospective interviews showed that the trial as performed was acceptable to patients. The treatment effect in the primary outcome measure, muscle strength, was statistically significant when inferred to the population level, though the effect size was modest. Secondary outcomes were statistically significant in a preplanned, fixed effects analysis within the four patients. The NHCI advised that it could potentially make reimbursement decisions based on the Fitting Evidence framework, should the trialists decide to apply for reimbursement. The MEB advised that for a licensing decision, the N-of-1 design is a last-resort option for demonstrating treatment benefit in a rare disease. N-of-1 trials alone do not provide enough evidence on potential risk. The MEB found the current trial inconclusive. It suggested doing a 2-armed trial of longer duration, possibly with a different outcome measure (postponement of corticosteroid use). It suggested engaging a consultancy or commercial sponsor, should the trialists decide to seek market authorization of the drug. CONCLUSIONS: In theory, evidence from aggregated N-of-1 trials is suitable for use in licensing and reimbursement decisions. The current example illustrates differences in interpretation of N-of-1 results by health authorities. In the era of personalized medicine, consensus is required on the interpretation of data from study designs geared to small groups. Demonstrating effectiveness of inexpensive medicines in small populations may require involvement of non-commercial parties, to preserve affordability.


Asunto(s)
Efedrina/metabolismo , Miastenia Gravis/metabolismo , Enfermedades Raras/metabolismo , Humanos , Miastenia Gravis/patología , Evaluación de Resultado en la Atención de Salud , Medicina de Precisión , Enfermedades Raras/patología , Estudios Retrospectivos
3.
Neuromuscul Disord ; 27(3): 259-265, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28007405

RESUMEN

We studied the effect and safety of ephedrine as add-on treatment for patients with myasthenia gravis with acetylcholine receptor antibodies (AChR MG), who do not sufficiently respond to standard treatment. Four patients with AChR MG were included in a placebo-controlled, double-blind, and randomised, multiple crossover series of n-of-1 trials. Each n-of-1 trial consisted of 3 cycles, in which two 5-day intervention periods were followed by 2 days washout. In each cycle, ephedrine 50 mg daily in 2 doses was compared with placebo in the alternate treatment period. Primary outcome was a change in QMG score. Add-on treatment with ephedrine compared with placebo improved QMG score by 1.0 point (95% confidence interval 0.21-1.79), which was significant for the group of trial patients as well as for the population treatment effect. Ephedrine also showed a significant trial average treatment effect for all secondary outcomes, improving MG Composite by 2.7, MG-ADL by 1.0 and VAS score for muscle strength by 1.1. Adverse events were mild and included palpitations, tremor and restlessness. Although all ECGs were normal, ephedrine prolonged the corrected QT interval. Ephedrine as add-on treatment for myasthenia gravis resulted in a small but consistent reduction of symptoms and weakness in patients with moderate disease severity.


Asunto(s)
Efedrina/farmacología , Inmunosupresores/uso terapéutico , Miastenia Gravis/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Receptores Colinérgicos/inmunología , Simpatomiméticos/farmacología , Adulto , Autoanticuerpos/sangre , Estudios Cruzados , Método Doble Ciego , Quimioterapia Combinada , Efedrina/administración & dosificación , Efedrina/efectos adversos , Femenino , Humanos , Inmunosupresores/administración & dosificación , Persona de Mediana Edad , Miastenia Gravis/inmunología , Simpatomiméticos/administración & dosificación , Simpatomiméticos/efectos adversos
4.
BMJ Open ; 5(7): e007863, 2015 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-26185179

RESUMEN

INTRODUCTION: Myasthenia gravis (MG), a rare neuromuscular disease, is often initially treated using acetylcholinesterase inhibitors. Patients who do not respond adequately depend on the use of corticosteroids or other immunosuppressive medication, but these may have serious side effects. Clinical observations suggest that ephedrine can diminish, postpone or even prevent the need for immunosuppressive therapy when added to acetylcholinesterase inhibitors or low-dose prednisone. In the Netherlands, ephedrine is not licensed for MG nor is reimbursement guaranteed. MG is a rare condition, and ephedrine might be indicated only in a subset of patients. Thus, randomised controlled trials comparing large groups are difficult to conduct. We, therefore, aim to aggregate data from a small series of n-of-1 trials (also known as single patient trials) to assess the effect of ephedrine as add-on treatment for MG. METHODS AND ANALYSIS: Single-centre, placebo-controlled, double-blind, randomised, multiple crossover n-of-1 studies in 4 adult patients with generalised MG who show inadequate improvement on pyridostigmine and/or immunosuppressive drugs. Each n-of-1 trial has 3 cycles of two 5-day intervention periods. TREATMENT: 25 mg ephedrine or placebo, twice daily. MAIN OUTCOME MEASURE: Quantitative Myasthenia Gravis (QMG) test. STATISTICAL ANALYSIS: fixed effects linear model for QMG for all patients combined. SECONDARY OUTCOME MEASURES: Clinical: effects on MG-Composite and MG-Activities of Daily Living (MG-ADL) scales; QMG at individual level; adverse events. Acceptability of trial design: number of patients eligible and enrolled; number of treatment cycles completed; patients' and caregivers' experiences. ETHICS AND DISSEMINATION: This study was approved by the Medical Ethics Committee of Leiden University Medical Center, No. P14.108. Results of the trial will be reported in a peer-reviewed publication. Regulatory stakeholders will comment on the suitability of the trial for market authorisation and reimbursement purposes. TRIAL REGISTRATION NUMBER: This study is registered under EudraCT number 2014-001355-23, protocol no. 40960, V.1.0, registration date 27 March 2014.


Asunto(s)
Estimulantes del Sistema Nervioso Central/uso terapéutico , Efedrina/uso terapéutico , Miastenia Gravis/tratamiento farmacológico , Actividades Cotidianas , Adulto , Actitud del Personal de Salud , Actitud Frente a la Salud , Protocolos Clínicos , Estudios Cruzados , Método Doble Ciego , Humanos , Uso Fuera de lo Indicado , Selección de Paciente , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Resultado del Tratamiento
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