Novel paclitaxel trihydrates. The paclitaxel trihydrates described herein are obtained by recrystallizing paclitaxel from a water/alcohol solution. Such recrystallization is known in the art to yield the one previously known paclitaxel crystalline trihydrate polymorph. Formation of the novel paclitaxel trihydrates described herein is induced by subjecting paclitaxel trihydrate crystals to an elevated pressure. As evidenced by NMR spectra, the novel paclitaxel trihydrates described herein have three-dimensional structures and/or water coordination geometry structures that are distinct from any previously known paclitaxel trihydrate.
