Karyopharm's Phase 3 SENTRY Trial in Myelofibrosis Met First Co-Primary Endpoint, Demonstrating Statistically Significant Improvement in Spleen Volume Reduction

– While Similar Symptom Improvement Was Observed Across the Two Arms Relative to Baseline, SENTRY Did Not Meet its Second Co-Primary Endpoint of Abs-TSS – – SENTRY Demonstrated a Rapid and Near Doubling of Patients Achieving SVR35 at Week 24, versus Ruxolitinib – – Promising Overall Survival Signal with >50% Reduction of Risk of Death versus Ruxolitinib – – Evidence of Potential Disease Modification with More Patients Achieving ≥20% Reductions in VAF as Early as Week 24 versus Ruxolitinib – – No New Safety Signals Identified – – Karyopharm will Meet with the FDA to Discuss the Totality of the Data and Potential sNDA Filing – – Conference Call Scheduled for Today at 8:00 a.m. ET – NEWTON, Mass.