Karyopharm Therapeutics Inc. is a clinical-stage pharmaceutical company focused on the discovery and development of drugs directed against nuclear transport targets for the treatment of cancer and other diseases. The Company is developing small molecule Selective Inhibitor of Nuclear Export (SINE), compounds that inhibits the nuclear export protein XPO1. Karyopharm is seeking the regulatory approval and commercialization of its lead drug candidate, selinexor (KPT-330), as a single orally administered agent in cancer indications with unmet clinical need, initially for hematologic malignancies. It is also advancing the clinical development of selinexor in multiple solid tumor indications. The Company has initiated three registration-directed trials in hematological cancers with selinexor and anticipates initiating a fourth registration-directed trial.