3.3.12. Cabazitaxel (CBZ): CBZ, being 3rd generation, semi-synthetic derivative of natural taxoids, is a microtubule inhibitor and is used for the treatment of various cancers like prostate cancer . As mentioned previously, the compatibility estimation of CBZ was not possible because of limitation in HSPiP software, incapable to process large size SMILES. The formulation results revealed that A-pBuOx-A was capable to solubilize all provided drug, i.e. up to 10 g/L (Figure ) (LC ≈ 50 wt.% and LE ≈ 100%). The crash point of this formulation was not determined by further increasing the CBZ feed. The aqueous solubility of CBZ was found to be 0.007 g/L (Table ). For A-pPentOx-A and A-pBuOzi-A, the CBZ solubility also kept on increasing with the increasing feed (until 8 g/L feed) and the achievable soluble CBZ was ≈ 6.8 g/L, while at 10 g/L CBZ feed, A-pPentOx-A gave 8.5 g/L and for A-pBuOzi-A, the solubility dropped to 5.3 g/L. Like for many other tested drugs, A-pPrOzi-A displayed comparatively, poor performance to solubilize the CBZ and the maximum soluble CBZ obtained was 1.5 g/L and also significant decrease in solubility was observed with the increasing CBZ feed. Thus, a strong polymer drug specificity was observed for the structural isomer pair i.e. A-pBuOx-A/A-pPrOzi-A, where the former appeared to be best solubilizer while the latter showed poor performance, very similar to the situation with paclitaxel, the first generation taxoid.