Belinostat is primarily used in the treatment of relapsed or refractory peripheral T-cell lymphoma (PTCL), a rare and aggressive type of non-Hodgkin lymphoma. It functions as a histone deacetylase (HDAC) inhibitor, which helps to regulate gene expression and induce apoptosis in cancer cells. The drug is administered intravenously and is often considered when other treatment options have failed. Its ability to target epigenetic modifications makes it a valuable option in oncology, particularly for patients with limited therapeutic alternatives. Additionally, ongoing research is exploring its potential in treating other types of cancers, such as ovarian cancer and soft tissue sarcoma, to expand its clinical applications.