The present invention is directed to a method of using compounds of Formula (I) to inhibit Cathepsin B. Specifically the compounds of the present invention are useful as therapeutic agents for the treatment of tumor invasion, metastasis, Alzheimer's Disease, arthritis, inflammatory diseases such as chronic and acute pancreatitis, inflammatory airway disease, and bone and joint disorders, including osteoporosis, osteoarthritis, rheumatoid arthritis, psoriasis, and other autoimmune disorders, liver fibrosis, including liver fibrosis associated with HCV, all types of steatosis (including non-alcoholic steatohepatitis) and alcohol-associated steatohepatitis, non-alcoholic fatty liver disease, forms of pulmonary fibrosis including idiopathic pulmonary fibrosis, pathological diagnosis of interstitial pneumonia following lung biopsy, renal fibrosis, cardiac fibrosis, retinal angiogenesis and fibrosis/gliosis in the eye, schleroderma, and systemic sclerosis. The compounds of Formula (I) are also useful for treating subjects with both HCV and fibrosis in a mammal, particularly liver fibrosis, and subjects affirmatively diagnosed or at risk for both HCV and liver fibrosis.