The most efficient polymer-based drug delivery system for delivering chemotherapy agents to solid tumors is still a subject of ongoing research and development. However, one promising approach is the use of polymeric micelles.Polymeric micelles are nanoscale, self-assembling structures formed by amphiphilic block copolymers. These copolymers consist of hydrophilic water-soluble and hydrophobic water-insoluble segments. In an aqueous environment, the hydrophobic segments aggregate to form the core of the micelle, while the hydrophilic segments form the outer shell. This core-shell structure allows for the encapsulation of hydrophobic chemotherapy drugs within the core, while the hydrophilic shell imparts stability and solubility in the bloodstream.The advantages of polymeric micelles for drug delivery include:1. Enhanced solubility and stability of hydrophobic drugs, which can improve their pharmacokinetics and biodistribution.2. Passive targeting of solid tumors through the enhanced permeability and retention EPR effect, which is a result of the leaky vasculature and poor lymphatic drainage in tumor tissues. This allows for the preferential accumulation of micelles in tumor sites, reducing systemic toxicity.3. The potential for active targeting by conjugating targeting ligands such as antibodies or peptides to the micelle surface, which can further increase the specificity of drug delivery to tumor cells.4. The ability to co-deliver multiple drugs with different physicochemical properties, enabling combination therapy and potentially overcoming drug resistance.Several polymeric micelle-based drug delivery systems are currently in various stages of preclinical and clinical development for cancer therapy. Examples include Genexol-PM paclitaxel-loaded polymeric micelles and NK105 micellar formulation of paclitaxel with a polyethylene glycol-polyaspartate block copolymer . While these systems show promise, further research and optimization are needed to fully realize the potential of polymeric micelles for efficient and targeted delivery of chemotherapy agents to solid tumors.