Epothilones are microtubule-stabilizing agents with potential anti-neoplastic actions.^1,2,3 They are natural macrolides that have high potency in both taxane-sensitive and taxane-resistant models.^2,3 Epothilone D is a desoxy form of epothilone B that inhibits the growth of a variety of cancer cells both in vitro (IC50 values range from 0.97 to 21 nM) and in mice.^3,4 Epothilone D is brain penetrant and reduces neurodegeneration in aged tau transgenic mice.^5,6 Effects include improved axonal transport, decreased tau neuropathology, and reduced hippocampal neuron loss.^5,6 Epothilone D also rescues microtubule defects and attenuates nigrostriatal degeneration in a mouse model of Parkinson’s disease.⁴