0001503802 2026-05-14 2026-05-14 false 0001503802 8-K 2026-05-14 Karyopharm Therapeutics Inc. DE 001-36167 26-3931704 85 Wells Avenue 2nd Floor Newton MA 02459 (617) 658-0600 false false false false Common Stock, $0.0001 par value KPTI NASDAQ false