Abstract: SA-PO725
Use of Composite Endpoint to Improve Feasibility of Clinical Trials in Peritoneal Dialysis
Session Information
- Peritoneal Dialysis - II
November 04, 2017 | Location: Hall H, Morial Convention Center
Abstract Time: 10:00 AM - 10:00 AM
Category: Dialysis
- 608 Peritoneal Dialysis
Authors
- Aufricht, Christoph, Medical University of Vienna, Vienna, Austria
- Herkner, Harald, Medical University Vienna, Vienna, Austria
- Kratochwill, Klaus, Medical University of Vienna, Vienna, Austria
- Vychytil, Andreas, Medical University Vienna, Vienna, Austria
Background
Peritoneal dialysis (PD) is frequently complicated by PD–related adverse events, such as peritoneal membrane damage and/or peritonitis. Currently used PD fluids likely contribute to pathological mechanisms responsible for these complications. Low feasibility to recruit PD populations for adequately powered trials may impair clinical development of improved PD fluids. In trials in which more than one outcome is thought to be affected by the treatment, the use of composite endpoint can be recommended. Here, we test the effect of introducing clinically relevant composite PD outcomes on clinical trial design in PD.
Methods
The composite outcome “Major Adverse Peritoneal Events (MAPE)” was designed based on incidence rates of 3 individual endpoints obtained from published clinical trials: ultrafiltration (component 1), peritoneal transport characteristics (2), and peritonitis rate (3). Taking into account that some patients could experience more than one event, several degrees of overlaps of events were investigated. Sample size calculations were carried out using a chi-square test for a parallel group design in binary composite endpoint MAPE with two-sided significance level of 5% to achieve power of 80%.
Results
Based on previously reported clinical trials, event rates of 33% were assumed for each individual component (1,2,3) for the control group. In a scenario with reduction of adverse events by 25%, adequately powered studies would need a sample of more than 1000 patients to test effects on ultrafiltration, peritoneal transport characteristics or peritonitis rate, when studied individually. Combining 2 of these outcome variables reduces the required sample by approximately half, whereas the composite outcome MAPE may reduce the needed sample size to 256 patients.
Conclusion
Introduction of the composite outcome MAPE, covering 3 major PD outcomes, increases power of future clinical trials in PD, thereby improving feasibility. This results in the need for significantly lower sample sizes for assessing clinically relevant effects on PD-related complications.