Used in the treatment of cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL), romidepsin is a histone deacetylase (HDAC) inhibitor that works by altering gene expression in cancer cells, leading to cell cycle arrest and apoptosis. It is administered intravenously and is typically reserved for patients who have not responded to other therapies. Its ability to reactivate silenced tumor suppressor genes makes it valuable in targeted cancer therapy, particularly in hematologic malignancies. Clinical studies continue to explore its potential in combination with other anticancer agents to enhance efficacy.