The importance of Poly(ethylene glycol) alternatives for overcoming PEG immunogenicity in drug delivery and bioconjugation

Thai Thanh Hoang Thi, Emily H. Pilkington, Dai Hai Nguyen, Jung Seok Lee, Ki Dong Park, Nghia P. Truong

Research output: Contribution to journalReview ArticleResearchpeer-review

377 Citations (Scopus)


Poly(ethylene glycol) (PEG) is widely used as a gold standard in bioconjugation and nanomedicine to prolong blood circulation time and improve drug efficacy. The conjugation of PEG to proteins, peptides, oligonucleotides (DNA, small interfering RNA (siRNA), microRNA (miRNA) and nanoparticles is a well-established technique known as PEGylation, with PEGylated products have been using in clinics for the last few decades. However, it is increasingly recognized that treating patients with PEGylated drugs can lead to the formation of antibodies that specifically recognize and bind to PEG (i.e., anti-PEG antibodies). Anti-PEG antibodies are also found in patients who have never been treated with PEGylated drugs but have consumed products containing PEG. Consequently, treating patients who have acquired anti-PEG antibodies with PEGylated drugs results in accelerated blood clearance, low drug efficacy, hypersensitivity, and, in some cases, life-threatening side effects. In this succinct review, we collate recent literature to draw the attention of polymer chemists to the issue of PEG immunogenicity in drug delivery and bioconjugation, thereby highlighting the importance of developing alternative polymers to replace PEG. Several promising yet imperfect alternatives to PEG are also discussed. To achieve asatisfactory alternative, further joint efforts of polymer chemists and scientists in related fields are urgently needed to design, synthesize and evaluate new alternatives to PEG.

Original languageEnglish
Article number298
Number of pages21
Issue number2
Publication statusPublished - Feb 2020


  • Anti-PEG antibody
  • Bioconjugation
  • Cancer
  • Drug delivery
  • Nanomedicine
  • PEG immunogenicity
  • PEGylation
  • Vaccine

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