Profile of idursulfase for the treatment of Hunter syndrome

Figures & data

Figure 1 Lysosomal recombinant iduronate-2-sulfatase transport.

Notes: M6P is a key targeting signal for lysosomal enzymes (E) that are destined for transport to lysosomes. The protein mannose residue is phosphorylated (green spot) in the cis-Golgi and meets the M6P receptor (red C) in the trans-Golgi network. Then, targeted enzymes are packaged into vesicles and transported to late endosomes where acid pH causes dissociation of M6P from its receptor. The M6P receptor is recycled from the late endosome to the trans-Golgi network, while the enzymes are ferried to their final destination in the lysosomes. Enzyme precursors can also reach the lysosome via the endocytic pathway binding M6P receptors on the plasmatic membrane.
Abbreviations: M6P, mannose-6-phosphate; ER, endoplasmic reticulum.

Table 1 Clinical, laboratory, and instrumental endpoints used to assess efficacy of treatment with idursulfase

Efficacy endpoints
Urinary glycosaminoglycans excretion Six-minute walk test Forced vital capacity Liver and spleen volumes Joint mobility

Table 2 Efficacy of treatment with idursulfase

Endpoints	Efficacy
Urinary glycosaminoglycans excretion	+
Six-minute walk test	+
Forced vital capacity	±
Liver and spleen volumes	+
Joint mobility	±
Growth	±
Cardiac disease	±
Skeletal disease	±
Obstructive sleep apnea	±
Functional capacity	+
Central nervous system involvement	−

Notes: +, efficacy; ±, doubtful efficacy; –, no efficacy.

Table 3 The most frequent adverse drug reactions observed during treatment with idursulfase

Adverse drug reaction
Headache Hypertension Flushing Wheezing Dyspnea Abdominal pain Nausea Dyspepsia Diarrhea Urticaria Rash Pruritus Chest pain Infusion-related reactions Pyrexia Infusion-site swelling

Figure 2 Protocol for transition to home infusions.

Abbreviations: MPS II, mucopolysaccharidosis type II; ERT, enzyme replacement therapy; IRRs, infusion-related reactions; FVC, forced vital capacity.