Bergantini et al. followed 23 patients with IPF who received nintedanib for 12 months and found that uninterrupted nintedanib treatment may have stabilized their serum KL-6 levels in serial tests, and that variation in serum KL-6 levels was correlated with serial variations in DLCO [60]. Here, MUC1 is linked to idiopathic pulmonary fibrosis.