Cathepsin L-IN-2 is primarily utilized in research settings to study the role of cathepsin L in various biological processes. It serves as a selective inhibitor, helping to elucidate the enzyme's involvement in cancer progression, as cathepsin L is known to contribute to tumor invasion and metastasis. Additionally, this compound is used to investigate its potential in treating viral infections, as cathepsin L plays a role in viral entry and replication. Researchers also explore its application in neurodegenerative diseases, where cathepsin L activity is linked to protein aggregation and cellular dysfunction. Its inhibitory properties make it a valuable tool for understanding disease mechanisms and developing targeted therapies.