ALC-0159ALC-0159 is a PEG/lipid conjugate, specifically, it is the N,N-dimyristylamide of 2-hydroxyacetic acid, O-pegylated to a PEG chain mass of about 2 kilodaltons. It is a non-ionic surfactant by its nature. It has been deployed in the Pfizer-BioNTech SARS-CoV-2 mRNA vaccine that contains the active ingredient tozinameran.