IRCT20210413050958N5 IRCT 2022-06-08 Mashhad University of Medical Sciences Effect of N-Acetyl-L-Leucine in treatment of Multiple Sulfatase Deficiency The effects of N-Acetyl-L-Leucine on the improvement of symptoms in A patient with Multiple Sulfatase Deficiency 2022-05-31 anticipated 1 Complete https://irct.ir/trial/63762 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Crossover, Purpose: Treatment, Randomization description: The drug allocation sequence is made in a simple random method. Sequentially numbered sealed envelopes are used to implement the random allocation sequence which opened by a person not involved in the project, Blinding description: The volunteer, care provider and statistician are blinded after assignment to intervention. So that, the supplements containers were coded as A and B by a non-researcher person and remained confidential until data analysis. The placebos are similar to the supplements regarding the weight and color. 2 Multiple sulfatase deficiency. Intervention 1: Subject in the intervention group receives N-Acetyl-L-Leucine caplets (daily intake of 2-4 gr depending on the subject’ weight) for 4 weeks (n=1) and then after a 4-weeks wash-out period, he/she is crossed over to the placebo. The participant takes the supplement every day, which is contained in an unlabeled bottle. Supplements are from Hubei ipure Biotech co., ltd (Shenzhen, China). Intervention 2: The subject receives a placebo caplet (daily consumption between 2 to 4 grams depending on the subject's weight) for 4 weeks (n=1) and then after a 4-weeks wash-out period, he/she is crossed over to the alternate regimen (N-Acetyl-L- Leucine). Participant takes a placebo every day orally in an unlabeled bottle. The placebo is prepared by from faculty of pharmacy (Mashhad, Iran) company. No - There is not a plan to make this available Justification or reason for not sharing IPD is Following a reasonable request, deidentified data will be shared.