KPT-330, also known as Selinexor, is primarily used in the treatment of certain types of cancer. It is particularly effective in managing multiple myeloma and diffuse large B-cell lymphoma, especially in cases where other treatments have failed. Selinexor works by inhibiting the export of tumor suppressor proteins and oncoprotein mRNAs from the nucleus to the cytoplasm, leading to the accumulation of these proteins in the nucleus. This process induces cancer cell apoptosis, effectively reducing tumor growth. In clinical settings, Selinexor is often administered orally and is used as part of combination therapies to enhance its efficacy. It has shown promise in improving progression-free survival and overall response rates in patients with relapsed or refractory cancers. Additionally, ongoing research is exploring its potential in treating other malignancies, including solid tumors and hematologic cancers. Its unique mechanism of action makes it a valuable option for patients who have developed resistance to conventional therapies.