Office of Biostatistics and Epidemiology, Center for Biologics Evaluation and Research, Food and Drug Administration, Rockville, MD, USA.
Am J Transplant. 2012 Jul;12(7):1898-907. doi: 10.1111/j.1600-6143.2012.04038.x. Epub 2012 Apr 5.
To estimate treatment effect size and other parameters required for planning the designs and analyses of future phase 3 islet transplant trials, we analyzed key clinical and laboratory outcomes of 347 allogeneic islet transplant recipients, using data from the Collaborative Islet Transplant Registry (CITR). At 1 year, approximately 59% of all transplant recipients were free of severe hypoglycemic events and maintained hemoglobin A1c (HbA1c) level of ≤ 6.5%. The Kaplan-Meier (KM) survival analyses showed that 69%, 54% and 44% of these 1-year responders maintained this composite endpoint at 2, 3 and 4 years, respectively. Ninety-one percent of all recipients were free of severe hypoglycemic episodes at 1 year. Furthermore, the KM survival estimates showed that 91%, 85% and 80% of these subjects maintained this clinical benefit at 2, 3 and 4 years, respectively. These results can be very useful in developing framework for study designs, sample size estimates, and statistical analysis plans for future pivotal trials of islet cell transplantation in type 1 diabetes.
为了估计治疗效果大小和其他参数，以便为未来的 3 期胰岛移植试验的设计和分析提供规划，我们分析了 347 例同种异体胰岛移植受者的关键临床和实验室结果，这些数据来自于协作胰岛移植登记处（CITR）。在 1 年时，约有 59%的所有移植受者没有发生严重低血糖事件，并且保持血红蛋白 A1c（HbA1c）水平≤6.5%。Kaplan-Meier（KM）生存分析显示，这些 1 年应答者中的 69%、54%和 44%分别在 2 年、3 年和 4 年时维持这一复合终点。91%的所有受者在 1 年时没有发生严重的低血糖发作。此外，KM 生存估计表明，这些受试者中的 91%、85%和 80%分别在 2 年、3 年和 4 年时维持了这一临床获益。这些结果对于制定未来 1 型糖尿病胰岛细胞移植的关键性试验的研究设计、样本量估计和统计分析计划非常有用。
