In 1999, Dr. Emil Kakkis at Los Angeles Biomedical Research Institute (LA BioMed) developed Enzyme Replacement Therapy to treat Hurler-Scheie Syndrome. In patients with mucopolysaccharidosis I, treatment with recombinant human α-L-iduronidase reduces lysosomal storage in the liver and ameliorates some clinical manifestations of the disease.

Bone marrow transplantation is an effective treatment for patients with Hurler’s syndrome, especially if it is performed early in the course of the disease, before the onset of developmental decline. However, the substantial morbidity and mortality of the procedure and the need for matched donor marrow limit its usefulness.

Their findings demonstrated that recombinant human α-L-iduronidase can reduce lysosomal storage and ameliorate some aspects of clinical disease in patients with mucopolysaccharidosis I. Long-term studies of enzyme-replacement therapy will be required to assess the overall effects of this treatment on morbidity and mortality.