PEGylation: Non-Immunogenic Delivery of Protein-Based Drugs

Some proteins, particularly enzymes, are available as drugs and many more are being investigated for their therapeutic potential. But many degrade quickly and lose effectiveness, and some can cause allergic reactions.

In the 1960s, researchers found that attaching protein fragments to proteins could reduce the immunogenicity of the protein. Subsequently, Dr. Frank Davis and colleagues found that polyethylene glycol (PEG) modification of these proteins reduced immunogenicity to such an extent that proteins could be developed for therapeutic use.

Under exclusive license to the PEG technology, Dr. Davis and Dr. Abraham Abuchowski founded Enzon Inc. in 1981 to develop the potential of modifying enzymes, proteins and peptides with PEG. Enzon has developed several advanced treatments for life- threatening illnesses, most notably a therapy for children who lack immune systems and another for childhood leukemia. Treatment with PEG-modified proteins results in fewer and smaller doses to the patient, reducing potential toxicity and cost of therapy.