Enhanced drug resistance suppression by serum-stable micelles from multi-arm amphiphilic block copolymers and tocopheryl polyethylene glycol 1000 succinate.

Aim: To develop a robust drug-delivery system using multi-arm amphiphilic block copolymers for enhanced efficacy in cancer therapy. Materials & methods: Two series of amphiphilic polymer micelles, PEG-b-PCLm and PEG-b-PCLm/TPGS, were synthesized. Doxorubicin (DOX) loading into the micelles was achieved via solvent dialysis. Results: The micelles displayed excellent biocompatibility, narrow size distribution, and uniform morphology. DOX-loaded micelles exhibited enhanced antitumor efficacy and increased drug accumulation at tumor sites compared with free DOX. Additionally, 4A-PEG47-b-PCL21/TPGS micelles effectively suppressed drug-resistant MCF-7/ADR cells. Conclusion: This study introduces a novel micelle formulation with exceptional serum stability and efficacy against drug resistance, promising for cancer therapy. It highlights innovative strategies for refining clinical translation and ensuring sustained efficacy and safety in vivo.