Objective: In the present study, we undertook to establish therapeutic equivalence with respect to peritonitis and technique failure between the Carex disconnect system (B. Braun Carex, Mirandola, Italy) and the standard Ultra system (Baxter Healthcare, Tokyo, Japan) in patients on continuous ambulatory peritoneal dialysis (CAPD).
Design: This multicenter, parallel group, randomized controlled trial involved 363 prevalent CAPD patients from 8 centers. The primary endpoint was peritonitis rate; secondary endpoints were technique failure and technical problems encountered. The duration of the evaluation was 1 year.
Results: The risk of peritonitis on Carex varied between the centers. We found a significant treatment-center interaction effect (likelihood ratio test: p = 0.03). The incidence rate ratio (IRR) of peritonitis on Carex as compared with Ultra ranged from 0.4 to 7.2. In two centers, Carex was inferior to Ultra with regard to peritonitis; but, in five centers, the results were inconclusive. Equivalence was not demonstrated in any center. The overall rate of peritonitis in the Carex group was twice that in the Ultra group [IRR: 2.18; 95% confidence interval (CI): 1.51 to 3.14]. Technique failure and technical problems were more common with the Carex system. Technique failure rate at 1 year was 44% in the Carex group and 22% in the Ultra group.
Conclusions: Equivalence between the Carex disconnect system and the Ultra disconnect system could not be demonstrated. The risk of peritonitis on Carex varied significantly between centers.