Nintedanib is a member of the class of oxindoles that is a kinase inhibitor used (in the form of its ethylsulfonate salt) for the treatment of idiopathic pulmonary fibrosis and cancer. It has a role as an antineoplastic agent, a tyrosine kinase inhibitor, a vascular endothelial growth factor receptor antagonist, a fibroblast growth factor receptor antagonist and an angiogenesis inhibitor. It is an aromatic ester, a methyl ester, a member of oxindoles, an enamine, an aromatic amine, an aromatic amide and a N-alkylpiperazine. It is a conjugate base of a nintedanib(1+).