Karyopharm Therapeutics Inc., a pharmaceutical company, engages in the discovery, development, and commercialization of various drugs directed against nuclear export and related targets for the treatment of cancer and other diseases. The company is developing small molecule selective inhibitor of nuclear export (SINE) compounds that inhibit the nuclear export protein exportin 1. Its lead compound is XPOVIO (selinexor) tablets for the treatment of patients with heavily pretreated multiple myeloma. The company develops BOSTON, which is in Phase 3 clinical trial for the treatment of patients with multiple myeloma; STORM, which is in Phase 2b single-arm clinical trial for evaluating oral selinexor in combination with standard, low-dose dexamethasone in heavily pretreated patients, relapsed or refractory myeloma; STOMP, which is in Phase 1b/2 multi-arm clinical trial for the treatment of ow-dose dexamethasone plus standard therapies, including Velcade, Kyprolis, Revlimid, and Pomalyst or Da