LDK1305 is a selective positive allosteric modulator of CB1 that promote the binding of the agonist CP55940 and inhibits binding of orthosteric inverse agonist SR141716A. LDK1305 is a beta-arrestin-biased ligand that induces cellular internalization of the receptor and recruitment of β-arrestin 2 in HEK293 cells. It stimulates also β-arrestin 1-dependent phosphorylation of the downstream kinases, ERK1/2, MEK, and Src.