N-Cyclopropyl-4-[6-(2,3-difluoro-4-methoxyphenoxy)-8-[(3,3,3-trifluoropropyl)amino]imidazo[1,2-b]pyridazin-3-yl]-2-methylbenzamide inhibits monopolar spindle 1, which is a serine/threonine/tyrosine kinase involved in cell division. It is also a potential antitumor agent.