Clinical studies examining the combination of paclitaxel (PTX) and everolimus (EVER), an mTOR inhibitor, have failed to result in significant improvements in efficacy and toxicity in patients with breast cancer (BC), relative to treatment with PTX alone. Recently, a research paper published in Molecular Pharmaceutics reported co-delivery of Paclitaxel and Everolimus by polymeric micelles at an optimal synergistic ratio to achieve specific, colocalized delivery of the combination therapy in BC cell lines. The nanoparticles were prepared from PLGA-PEG and PLGA-PEG-FITC (Nanosoft Polymers) had an average diameter of less than 100 nm and were capable of in vitro retention of the encapsulated PTX and EVER at the optimal synergistic molar ratio for over 7 days. The uptake of FITC-labeled NPs in SKBR3 cells was evaluated by flow cytometry, with approximately 41% of cells demonstrating detectable fluorescence after 24 h of exposure. The thorough and systematic approach used in this study to determine and evaluate a synergistic PTX:EVER ratio in conjunction with a potentially promising delivery vector for the drug combination could offer a future clinical benefit for patients with BC. Mol Pharm. 2018 Jun 14. doi: 10.1021/acs.molpharmaceut.8b00217.