PEGylation

PEGylation refers to the covalent (or less commonly, non-covalent) attachment of polyethylene glycol (PEG) polymers to biologic drugs, proteins, peptides, or nanoparticles. This process "masks" the therapeutic agent, preventing immune system recognition and clearance, increases the hydrodynamic size to reduce renal filtration, provides resistance to proteolytic degradation, and generally prolongs the half-life and alter pharmacokinetics of the drug. PEGylation is widely used in clinical pharmaceuticals, especially for protein and nanoparticle therapeutics, but has recognized drawbacks: patients may develop immune responses against PEG itself (formation of anti-PEG antibodies), which can accelerate drug clearance and pose safety concerns. PEGylation is thus a pharmaceutical modification strategy and does not represent a molecular drug target or receptor.

Other names

PEG conjugationPEG modification

Covalent attachment of PEG chains shields therapeutic agents from immune recognition, reduces renal clearance, and increases stability. PEGylation masks surface epitopes, decreasing immune detection by antibodies and immune cells.