Spastazoline is a potent, cell-permeable and selective spastin (a microtubule-severing AAA (ATPases associated with diverse cellular activities) protein) inhibitor with IC50 of 99 nM for Human spastin. Spastazoline does not inhibit ATPase activity of a recombinant human VPS4 (another AAA protein required for intercellular bridge disassembly).