Activity and Clinical Pharmacology of Rebif

To my science friends: more than you wanted to know about Rebif.

Rebif (Interferon beta-1a) is a purified , sterile glycoprotein product produced by recombinant DNA techniques and formulated for use by injection. The active ingredient of Rebif is produced by genetically engineered Chinese Hamster Ovary (CHO) cells. Interferon beta-1a is a highly purified glycoprotien that has 166 amino acids and an approximate molecular weight of 22,500 daltons. It contains a single N-linked carbohydrate moiety attached to Asn-80 similar to that of natural human Interferon beta.

The specific activity of Rebif is approximately 0.27 million international units (MIU)/μg interferon beta-1a. The unit measurement is derived by comparing the antiviral activity of the product to a in-house natural hIFN-B NIH standard that is obtained from human fibroblasts (BILS 11), which has been calibrated against the NIH natural hIFN-B standard (GB 23-902-531).

Interferons are a family of naturally occurring proteins, which have molecular weights ranging from 15, 000 to 21,000 daltons. Three major classes of interferons have been identified: alpha, beta, gamma. Interferon beta, interferon alpha and interferon gamma have overlapping yet distinct biologic activities.