ALC-0159 is a PEG-lipid conjugate (i.e. PEGylated lipid), specifically, it is the N,N-dimyristylamide of 2-hydroxyacetic acid, O-pegylated to a PEG chain mass of about 2 kilodaltons.
AxisPharm offers 4000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.