imiglucerase - Medications

Imiglucerase is a hydrolytic lysosomal glucocerebrosidase-specific enzyme. It is an analogue of the human enzyme b-glucocerebrosidase (b-D-glucosyl-N-acylsphingosine glucohydrolase, E.C. 3.2.1.45), produced by recombinant DNA technology using mammalian cell culture (Chinese hamster ovary). Purified imiglucerase is a monomeric glycoprotein of 497 amino acids, containing 4 N-linked glycosylation sites (Mr=60,430). Imiglucerase differs from placental glucocerebrosidase by one amino acid at position 495, where histidine is substituted for arginine. The oligosaccharide chains at the glycosylation sites have been modified to terminate in mannose sugars. The modified carbohydrate structures on imiglucerase are somewhat different from those on placental glucocerebrosidase. CEREZYME (imiglucerase) for injection is intended for intravenous use. It is supplied as a sterile, nonpyrogenic, white to off-white lyophilized powder for reconstitution with Sterile Water for Injection, USP. Each single-dose vial contains 424 units imiglucerase, mannitol (340 mg), polysorbate 80, NF (1.06 mg), and sodium citrates: disodium hydrogen citrate (36 mg) and trisodium citrate (104 mg). An enzyme unit (U) is defined as the amount of enzyme that catalyzes the hydrolysis of 1 micromole of the synthetic substrate para-nitrophenyl-b-D-glucopyranoside (pNP-Glc) per minute at 37°C. Reconstituted solutions have a pH of approximately 6.1.