Patent ID: 8501906

Claim:
A compound for treating cancer comprising: an anti-cancer chemotherapeutic agent linked to an insulin-like growth factor-1 (IGF-1) receptor ligand; wherein the IGF-1 receptor ligand is a variant IGF-1 that has reduced binding affinity for soluble IGF-1 binding proteins compared to wild-type IGF-1 wherein the variant IGF-1 comprises the polypeptide structure A 1 -A 2 -A 3 -A 4 -LCG-A 5 -A 6 -LV-A 7 -AL-A 8 -A 9 -R 1 , wherein A 1 is G, V, or FV; A 2 is P or N; A 3 is E or Q; A 4 is T, H, or A; A 5 is A or S; A 6 is E or H; A 7 is D or E; A 8 is Q or Y; A 9 is F or L; and R 1 is SEQ ID NO:6; provided the variant IGF-1 does not consist of SEQ ID NO:1; wherein the variant IGF-1 does not comprise SEQ ID NO:11; wherein the variant IGF-1 comprises SEQ ID NO:14, SEQ ID NO:15, SEQ ID NO:16, or SEQ ID NO:17.