Agalsidase beta

Source: UK SPC (eMC) §4.2 for Fabrazyme 35mg powder for concentrate for solution for infusion (https://www.medicines.org.uk/emc/product/15500/smpc). Treatment should be supervised by a physician experienced in the management of patients with Fabry disease or other inherited metabolic diseases. VERBATIM: 'The recommended dose of Fabrazyme is 1 mg/kg body weight administered once every 2 weeks as an intravenous infusion.' INFUSION RATE ESCALATION: after patient tolerance is well established, the infusion rate may be increased in increments of 0.05 to 0.083 mg/min (increments of 3 to 5 mg/hour) with each subsequent infusion. In clinical trials with classic patients the rate was increased incrementally to reach a minimum duration of 2 hours, achieved after 8 initial infusions at 0.25 mg/min (15 mg/hour) without any infusion-associated reactions (IARs), change in infusion rate or infusion interruption. A further decrease of infusion time to 1.5 hours was allowed for patients without new IARs during the last 10 infusions or reported serious adverse events within the last 5 infusions. Each rate increment of 0.083 mg/min (approximately 5 mg/hour) was maintained for 3 consecutive infusions without any new IARs, change in infusion rate or infusion interruption before subsequent rate increases. HOME INFUSION: may be considered for patients who are tolerating their infusions well, after evaluation and recommendation by the treating physician; patients experiencing adverse events during home infusion must immediately stop the infusion and seek the attention of a healthcare professional, and subsequent infusions may need to occur in a clinical setting. Dose and infusion rate should remain constant while at home and not be changed without supervision of a healthcare professional. ELDERLY: safety and efficacy in patients older than 65 years have not been established and no dosage regimen can presently be recommended. HEPATIC IMPAIRMENT: studies in patients with hepatic insufficiency have not been performed. §4.5 interactions was not present in the fetched bundle.

SPC §4.2 states 'No dose adjustment is necessary for children 8-16 years' — i.e. the same 1 mg/kg every 2 weeks regimen as adults. Safety and efficacy in children aged 0 to 7 years have not yet been established: no recommendation on posology can be made in children aged 5 to 7 years, and no data are available in children 0 to 4 years. For patients weighing under 30 kg the maximum infusion rate should remain at 0.25 mg/min (15 mg/hour) — the stepwise rate escalation used in larger patients does not apply.