Iduronidase (EC 3.2.1.76, L-iduronidase, α-L-iduronidase, laronidase), sold as Aldurazyme, is an enzyme with the systematic name glycosaminoglycan α-L-iduronohydrolase.
[5] The defective α-L-iduronidase results in an accumulation of heparan and dermatan sulfate within phagocytes, endothelium, smooth muscle cells, neurons, and fibroblasts.
Produced in Chinese hamster ovaries by recombinant DNA technology, Aldurazyme is manufactured by BioMarin Pharmaceutical Inc. and distributed by Genzyme Corporation (a subsidiary of Sanofi).
[10] Aldurazyme is indicated in the EU for long-term enzyme replacement therapy in patients with a confirmed diagnosis of mucopolysaccharidosis I (MPS I; α-L-iduronidase deficiency) to treat the nonneurological manifestations of the disease.
[13] Clinical trials and post-market safety data indicate that the most common adverse side effect of Aldurazyme is allergic reaction.
[13] In order to prevent allergic reaction and respiratory distress, the packet insert of Aldurazyme suggests that patients be administered antihistamines before infusion.
)[13] In a 2002 memorandum, Melanie Hartsough, Ph.D., DTP of the FDA's Department of Health and Human Services stated, "Aggregation of product could enhance immune responses, specifically neutralizing antibody, which may limit the response to therapy, whereas highly deaggregated product may induce immune tolerance."
According to Aldurazyme's website, the most common adverse effects observed in a 26-week, placebo-controlled clinical trial of patients 6 years old or older are flushing, pyrexia, headache, and rash.
[13] The website also states that in a 52-week open-label uncontrolled clinical trial, the most common serious reactions in children younger than 6 were "otitis media (20%), and central venous catherization required for ALDURAZYME infusion (15%).
Other commonly reported infusion reactions occurring in ≥5% of patients were pallor, tremor, respiratory distress, wheezing, crepitations (pulmonary), pruritus, and rash.