Recombinant Interferons Beta-1a and Beta-1b: Protein Structural Features and Problematic Issues with Identity Confirmation

Drugs based on recombinant interferons are in high demand in clinical practice for first-line therapy of multiple sclerosis. Drugs based on recombinant interferons -1a and -1b are registered in the Russian Federation. These proteins have different production technologies and, hence, structures. Recombinant interferon -1a is a glycosylated protein with a structure close to that of endogenous human interferon. Recombinant interferon -1b is a non-glycosylated protein that differs by two amino-acid residues from interferon -1a. These structural features influence the biological properties of drugs based on interferons -1a and -1b, in particular, their clinical efficacy, side effects, and induction intensity of neutralizing antibodies. For this reason, a laboratory pharmaceutical examination of the drug quality of interferons should include confirmation of the specific biological activity and the correspondence of the target protein to the claimed structure. However, domestic and international pharmacopoeial requirements for quality assessment of interferon--based drugs are not currently fully adequate. Formulation of unified domestic requirements would allow the registration process to be optimized and provide a basis for harmonization of domestic and international requirements.