Karyopharm selinexor data from late-stage soft tissue cancer study in presentation

 

• Karyopharm Therapeutics (KPTI -1.5%) has announced presentation of positive results from the Phase 3 portion of SEAL study evaluating single agent, oral XPOVIO (selinexor) versus matching placebo in patients with liposarcoma at the Connective Tissue Oncology Society 2020 Annual Meeting. Plans to submit US marketing application during Q1 of 2021.
• As previously reported, the SEAL study met its primary endpoint of a statistically significant increase in median progression-free survival (PFS) in patients with at least two prior therapies.
• Median PFS in the XPOVIO arm was 2.83 months compared to 2.07 months in the placebo arm (hazard ratio=0.70). Data indicates that XPOVIO reduced the risk of disease progression or death by ~30%, compared to placebo.
• Estimated 6-month PFS survival probability was 23.9% in selinexor arm compared to 13.9% on placebo, with 12-month PFS survival probability of 8.4% compared to 2%.
• Also, data suggested that 7.5% of patients on the selinexor arm had more than 15% reduction in their disease burden as measured by target lesion size while none in placebo.
• The most common treatment-related adverse events (AEs) were cytopenias, along with gastrointestinal and constitutional symptoms, manageable with dose modifications and/or standard supportive care.
• XPOVIO is currently FDA approved for the treatment of relapsed or refractory multiple myeloma and relapsed or refractory diffuse large B-cell lymphoma.
• Karyopharm has also submitted a supplemental marketing application with FDA for label expansion to include XPOVIO as a treatment for patients with multiple myeloma after at least one prior line of therapy. Action date is March 19, 2021.
• https://seekingalpha.com/news/3638376-karyopharms-selinexor-data-from-late-stage-soft-tissue-cancer-study-in-oral-presentation