Efficacy of genestein as food supplement in patients with the Sanfilippo syndrome (an extension study).

Sanfilippo syndrome (MPS III) is an inborn errors of lysosomal degradation of the glycosaminoglycan heparan sulphate (GAGs). Accumulation of heparan sulfate, results in progressive and severe mental deterioration, which is the clinical hallmark of MPS III. Genestein (an isoflavone) is a natural component of the soy-bean. Genistein inhibits GAGs synthesis in vitro and a recent small and open-label study suggested clinical relevant effects of genestein in MPS III patients. In June 2009 a double blind placebo controlled study on the effect of genestein was initiated in the Netherlands. Thirty patients with MPS III type A, B or C are included in this study and receiving either placebo or genestein (10 mg/kg) during two 6 month periods in a cross-over design The outcome of genestein on urinary GAG excretion, plasma heparan sulphate, tissue (skin biopsy) concentration of heparan sulphate, hair structure, cognitive state and behavioural abnormalities will be studied. Currently the trial is still ongoing and first results are expected the end of 2010. Our study will be the extension study of the previous mentioned study.

Genestein inhibits the synthesis of heparan sulphate and can possibly slow down disease progression in Sanfilippo Syndrome patients.

Baseline, 6 months and 12 months.

During a 12 month period all particpating patients will receive genestein as food supplement. Genestein dose will be calculated according to the weight of the patients (10 mg/kg/day). The start assessment of this study equals the last assessment of the double blind controlled trial.