Karyoharm Starts Phase 3 for Myelofibrosis

Phase 3 Study is Supported by Previously Presented Phase 1 Study Results, Including a 78.6% SVR35 and 58.3% TSS50 in Intent to Treat Patients at Week 24 at the 60mg Dose Karyopharm Therapeutics Inc. (Nasdaq: KPTI), a commercial-stage pharmaceutical company pioneering novel cancer therapies, today announced the initiation of a pivotal Phase 3 clinical trial (XPORT-MF-034) (NCT04562389) to assess the efficacy and safety of once-weekly selinexor 60mg in combination with ruxolitinib in JAKi-naïve patients with myelofibrosis. The randomized, double-blind, placebo-controlled study is expected to enroll 306 JAKi-naive patients with intermediate or high-risk myelofibrosis. Patients will be randomized 2:1 to ruxolitinib plus selinexor 60mg or ruxolitinib plus placebo in 28-day cycles. Ruxolitinib dose will be determined by the investigators based on the patients' baseline platelet count per the drug's prescribing information. The co-primary endpoints of the study are spleen volume response rate of ≥ 35% (SVR35) and symptom improvement of ≥ 50% (TSS50) at week 24, with a key secondary endpoint of anemia response at week 24. https://www.biospace.com/article/releases/karyopharm-initiates-pivotal-phase-3-study-of-xpo1-inhibitor-selinexor-and-ruxolitinib-in-jak-inhibitor-jaki-naive-myelofibrosis/