L-Cysteine in Peritoneal Dialysis

Study Overview
=================
Brief Summary
-----------------
Over the last decades, peritoneal dialysis has grown worldwide to become one of the most common modalities of renal replacement therapy, particularly in developing or newly industrialized countries, such as India, China, Korea, Turkey, Malaysia, Mexico and Brazil. Peritoneal dialysis has been associated with an initial survival benefit compared to hemodialysis, although this advantage becomes less apparent over time, likely due to the progressive loss of residual renal function and the development of pathological alterations of peritoneum . Recent results suggest that an antioxidant therapy by N-acetyl-cysteine oral supplementation may improve residual renal function in peritoneal dialysis patients. This finding may have major clinical relevance, as preserving residual renal function in peritoneal dialysis patients has been associated with improved survival . Aim of the present randomized, double-blind, crossover study is to confirm the preliminary evidence of the beneficial effects of antioxidant agents on residual renal function by using the L-enantiomeric form of cysteine in 10 prevalent peritoneal dialysis patients with residual diuresis.

Official Title
-----------------
A PROSPECTIVE, RANDOMIZED, DOUBLE-BLIND, CROSS-OVER STUDY TO EVALUATE THE RENAL AND BIOHUMORAL EFFECTS OF L-CYSTEINE COMPARED TO PLACEBO IN STABLE PERITONEAL DIALYSIS PATIENTS WITH RESIDUAL DIURESIS

Conditions
-----------------
Uremia

Intervention / Treatment
-----------------
* Dietary Supplement: L-cysteine
* Other: Placebo


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Males and females aged ≥ 18 years; Chronic automated peritoneal dialysis; Residual 24-hour diuresis ≥ 100 ml with less than 30% changes over the three months preceding randomization; Written informed consent. Exclusion Criteria: Chronic automated peritoneal dialysis therapy since less than three months; Diabetes mellitus; Acute peritonitis during the three months before enrollment; Concomitant treatment with other antioxidant agents (including N-acetyl-cysteine and vitamin C); Cystinuria; Pregnancy or breastfeeding; Childbearing potential without reliable contraceptive methods during the whole study period; Alcohol or drug (excluding tobacco) abuse; Inability to comply with the study procedures during the whole study period, legal incapacity; Cancer and any severe systemic disease or clinical condition that may jeopardize data interpretation or completion of the study.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: L-cysteine (Biocysan®)<br>Study subjects will take one tablet of L-cysteine or placebo every morning four times a week and two tablets of L-cysteine or placebo three times a week during the whole study period | Dietary Supplement: L-cysteine<br> <br> * Other names: Biocysan®;|
| Placebo Comparator: Placebo<br>Study subjects will take one tablet of L-cysteine or placebo every morning four times a week and two tablets of L-cysteine or placebo three times a week during the whole study period | Other: Placebo<br> <br> |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 24-hour urine output |  | Changes from Baseline at 1,2 and 3 month. | 
| Measured Glomerular Filtration Rate (GFR) |  | Changes from baseline at 1, 2 and 3 month. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Office systolic, diastolic, pulse and mean blood pressure |  | Changes from Baseline at 1,2 and 3 month. | 
| Urinary albumin excretion. |  | Changes from Baseline at 1,2 and 3 month. | 
| 2.27% Peritoneal Equilibration test (PET) |  | Changes from Baseline at 1,2 and 3 month. | 
| Pulse wave velocity (measured by tonometry) |  | Changes from Baseline at 1,2 and 3 month. | 
| Augmentation Index (measured by tonometry) |  | Changes from Baseline at 1,2 and 3 month. | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Diuresis, L-Cysteine, Peritoneal dialysis, Glomerular filtration rate, Peritoneal function, Inflammation