MLN8237 is a selective Aurora kinase A inhibitor with median IC50 of 61 nM. MLN8237 (Alisertib) is a second-generation, orally bioavailable, highly selective small molecule inhibitor of the Aurora A kinase (serine/threonine protein kinase) with potential antineoplastic activity. MLN8237 (Alisertib) binds to and inhibits Aurora A kinase, which may result in disruption of the assembly of the mitotic spindle apparatus, disruption of chromosome segregation, and inhibition of cell proliferation.