d-Alanine Supplementation for Chronic Kidney Disease: A Study Protocol for a Pilot Randomized Controlled Trial

Patients with chronic kidney disease (CKD) are at high risk for kidney failure and cardiovascular events. d-alanine administration prevented kidney damage in a murine acute kidney injury model. This pilot trial aims to assist the design of a larger trial on the efficacy and safety of d-alanine intake on kidney function in patients with CKD. This pilot, open-label, randomized controlled trial will enroll 24 patients with sustained albuminuria or proteinuria. Participants will be randomized in a 1:1 ratio to receive 3 g of d-alanine supplementation per day for 12 weeks or standard care alone. The primary endpoint will be change in albuminuria from baseline to 12 weeks. The secondary endpoints include changes in estimated glomerular filtration rate and other clinical parameters. Safety will be evaluated according to adverse events and laboratory parameters. The findings of this trial are expected to help design a larger-scale trial of d-alanine and support further development of d-alanine as a novel nutrition management for CKD.