Recent Advances in Polymeric Nanocarriers for Breast Cancer Drug Delivery

Abstract Breast cancer remains a major global health concern, highlighting the need for advanced drug delivery strategies that can improve therapeutic efficacy while minimizing systemic toxicity. Although several reviews have discussed polymeric nanocarriers for breast cancer therapy, many have primarily focused on specific polymeric platforms, individual stimuli-responsive mechanisms, or conventional formulation strategies, with limited integration of emerging biomimetic and biologically inspired approaches and the most recent advances in the field. This review addresses this gap by providing a comprehensive and critical assessment of recent developments in polymeric nanocarriers for breast cancer drug delivery, with particular emphasis on pH-responsive and other stimuli-sensitive systems, chemical and surface modifications, advanced formulation strategies, and emerging polymer−lipid hybrid, biomimetic, and extracellular vesicle-inspired nanocarriers. The review further highlights how these approaches can improve drug loading, controlled release, tumor-specific accumulation, cellular uptake, and therapeutic efficacy while reducing systemic toxicity. In addition, current challenges related to stability, reproducibility, scalability, safety, and clinical translation are critically discussed to identify key directions for future development. By integrating conventional polymeric strategies with emerging biomimetic and multifunctional platforms, this review provides a contemporary framework for understanding the evolution of polymeric nanocarriers and identifying opportunities for more precise and clinically translatable breast cancer therapy.