Thymectomy in Non-Thymomatous MG Patients on Prednisone

描述（由申请人提供）：MGTX是一项多中心、单盲、随机研究，比较接受强的松治疗的非胸腺瘤性重症肌无力（MG）患者的胸腺切除术和非胸腺切除术。这个由国家卫生研究院赞助的项目于2005年9月启动。招募目标是200名受试者-100名胸腺切除术加强的松和100名强的松单独。这项申请是为了延长这项拨款，将招募期再延长两年，并在2012年11月之前完成招募，并对患者进行为期三年的随访。主要结局和其他结局指标与原始方案相同。计划是继续招募和随访所有受试者，随机，保持盲法，直到最后一个入组受试者完成所有三年的研究。该计划与DSMB和研究人员批准的最初拨款一致，但现在对一些患者的随访时间更长（长达6年）。对于本次更新，我们提供了以下原始的具体目标、研究设计的细节、研究进展报告，包括招募结果和迄今为止加强招募的策略、研究核心组成部分（临床协调中心、数据协调中心和MG研究中的相关生物标志物）的细节、所有行政活动的细节、研究人群的基线人口统计数据、数据的数量和质量、完成研究的时间表。并概述当前MG治疗领域及其对本研究的影响。我们对原始研究的唯一建议是将样本量从200个减少到150个。最初的样本量计算被夸大，以确保足够的样本量用于预期的退出和审稿人提出的亚组假设。此次修订至150名受试者是基于我们三年的招募经验对招募能力的现实估计，以及150名患者（本次申请中增加了70名）仍然足以满足我们的主要特定目标，并且可以在本次预算申请中完成。

DESCRIPTION (provided by applicant): The MGTX is a multi-center, single-blind, randomized study comparing thymectomy to no thymectomy in non-thymomatous myasthenia gravis (MG) patients receiving prednisone. This NINDS-sponsored project was initiated in September, 2005. The recruitment goal has been 200 subjects -100 to thymectomy plus prednisone and 100 to prednisone alone. This application is for renewal of this grant to extend the recruitment period for an additional two years and complete recruitment by November 2012 and follow patients for three years. The primary outcome and other outcome measures are unchanged from the original protocol. The plan is to continue recruitment and follow-up of all subjects, as randomized, with blinding being maintained until the last enrolled subject has completed all three years of the study. This plan is consistent from the original grant as approved by the study DSMB as well as the investigators, but will now have a longer follow-up for some patients (out to 6 years). For this renewal, we provide below the original specific aims, details of the study design, a study progress report including recruitment results and strategies to enhance recruitment to date, details of the study core components (Clinical Coordinating Center, Data Coordinating Center, and the associated Biomarker in MG study), details of all administrative activities, the baseline demographics of the study population, volume and quality of the data, a timeline for the completion of the study, and an overview of the current MG therapeutic arena and its impact on this study. The only changes we propose from the original study are to reduce the sample size from 200 to 150. The original sample size calculations were inflated to insure adequate sample sizes for anticipated drop-outs and subgroup hypotheses raised by the reviewers. This revision to 150 subjects is based on realistic estimates of our ability to recruit derived from a three-year experience of enrollment and the fact that the 150 total patients (70 additional in this request) remains adequate for our primary specific aim and can be completed within this budget request.