From PEG to randomized PEG: a macromolecular strategy tackling PEG immunogenicity

Area of Science:

• Nanomedicine
• Polymer Chemistry
• Immunology

Background:

• PEGylation is vital in nanomedicine for drug delivery.
• Anti-PEG antibodies (APAs) reduce efficacy and pose safety risks.
• Need for next-generation nanomedicine solutions due to APA prevalence.

Purpose of the Study:

• To introduce and evaluate randomized PEG (rPEG) as a next-generation nanomedicine alternative.
• To assess rPEG's immunogenicity, safety, and performance in nanoparticle applications.
• To investigate rPEG's potential to overcome APA-related challenges.

Main Methods:

• rPEG synthesized by random incorporation of glycidyl methyl ether.
• Antigenicity assessed using ELISA, MST, and FCS analysis.
• In vitro studies for cytotoxicity, blood interaction, and complement activation.
• Nanoparticle formulations (micelles, lipid nanoparticles, liposomes) evaluated in vitro and in vivo.

Main Results:

• rPEG demonstrated significantly reduced antigenicity compared to traditional PEG.
• In vitro studies confirmed rPEG's non-cytotoxicity and lack of adverse blood interactions.
• rPEG-based nanoparticles showed reduced immunogenicity and comparable performance to PEGylated counterparts.
• In vivo studies showed rPEG-liposomes avoided accelerated blood clearance, even after PEG immunization.

Conclusions:

• rPEG is a highly promising alternative to PEGylation, addressing APA concerns.
• rPEG offers reduced immunogenicity while maintaining essential polymer properties.
• Further optimization of rPEG's stealth performance is warranted for broader clinical application.