Patent ID: 8057787

Claim:
A modified interferon beta (IFN beta) cytokine, wherein said modified IFN beta cytokine differs from an unmodified IFN beta cytokine by two amino acid substitutions, wherein said unmodified IFN beta cytokine comprises the amino acid sequence of SEQ ID NO: 196, said two amino acid substitutions being either: (a) substitution of the 5th and 47th positions in SEQ ID NO: 196, with aspartic acid and isoleucine, respectively; or (b) substitution of the 5th and 47th positions in SEQ ID NO: 196, with asparagine and isoleucine, respectively; or (c) substitution of the 6th and 47th positions in SEQ ID NO: 196, with glutamine and isoleucine, respectively, and wherein said two amino acid substitutions confer increased resistance to proteolysis over the unmodified IFN beta cytokine.