Long R3 IGF-I (LR3 IGF-I) is a 9.2 kDa synthetic analog of IGF-I that is generated by modifying the aa sequence for mature human IGF-I. The LR3IGF-1 is a long-term analog of human IGF-1, specifically designed and manufactured for mammalian cell culture to support large-scale manufacturing of recombinant biopharmaceuticals. LR3 IGF-I, an analogue of insulin-like growth factor (IGF)-I, was used in biopharmaceutical protein production in mammalian cells.