Patent ID: 7981864

Claim:
A targeted therapeutic fusion protein comprising: a lysosomal enzyme; and a mutein of human IGF-I having an amino acid sequence at least 80% identical to mature human IGF-I (SEQ ID NO:1); wherein the mutein of IGF-I comprises an amino acid substitution selected from the group consisting of leucine at a position corresponding to Tyr 60 , leucine at a position corresponding to Tyr 24 , serine at a position corresponding to Phe 16 , and lysine at a position corresponding to Glu 9 , or amino acid substitutions at positions corresponding to Arg 55 and Arg 56 , of mature human IGF-I (SEQ ID NO:1); and wherein the mutein binds to the human cation-independent mannose-6-phosphate receptor in a mannose-6-phosphate-independent manner.