Olitigaltin (TD-139, GB0-139) is a potent and selective inhibitor of galectin-3 with Kd of 0.036 µM over galectin-1 and galectin-7 with Kd of 2.2 µM and 32 µM, respectively. TD-139 is used potentially for the treatment of idiopathic pulmonary fibrosis (IPF).