The most expensive prescription medication available currently is Idursulfase, the recombinant form of the human lysosomal enzyme, iduronate-2-sulfatase. It is approved for use as enzyme replacement therapy in patients with Hunter syndrome(Mucopolysaccharidosis II, MPS II). Currently, the only commecial available Idursulfase goes under the trade name, Elaprase™, created via recombinant DNA technology in a human cell line by the company Shire Human Genetics Therapies, Inc.
It is dosed in 6 mg vial for intravenous administration. The recommended dose is 0.5 mg/kg every week by intravenous infusion over one to three hours. Idursulfase costs $4,215 for a 6 mg vial and the cost for treatment of a 35 kg patient is $657,000 per year.
Due to its high cost and inconsistent results, however, the Canadian Expert Drug Advisory Committee (CEDAC) recommends that Idursulfase not be listed as plausible therapy (covered under universal health care), however it is available in the U.S. if the patient is able to pay for it.