Karyopharm's Selinexor Combination Shows Spleen Volume Reduction in Myelofibrosis Trial

Event summary

  • Karyopharm's Phase 3 SENTRY trial met its first co-primary endpoint, showing statistically significant spleen volume reduction in myelofibrosis patients treated with selinexor plus ruxolitinib.
  • 50% of patients in the combination arm achieved ≥35% spleen volume reduction at week 24, compared to 28% in the ruxolitinib-alone arm.
  • The trial did not meet its second co-primary endpoint of symptom improvement, with similar Abs-TSS improvements observed in both arms.
  • A promising overall survival signal was observed, with a hazard ratio of 0.43 for the combination arm.
  • Karyopharm plans to meet with the FDA to discuss potential supplemental new drug application (sNDA) filing.

The big picture

Karyopharm's Phase 3 SENTRY trial results position selinexor as a potential new option for myelofibrosis patients, addressing a critical unmet need in a rare blood cancer market currently dominated by JAK inhibitors. The trial's mixed outcomes—statistically significant spleen volume reduction but no difference in symptom improvement—highlight the challenges of developing combination therapies in oncology. The promising overall survival signal could be a key differentiator if validated in further analyses.

What we're watching

Regulatory Pathway
Whether the FDA will accept the SENTRY data for a potential sNDA filing, given the mixed results on co-primary endpoints.
Commercial Strategy
How Karyopharm positions selinexor as a combination therapy in myelofibrosis, given the current market dominance of JAK inhibitors like ruxolitinib.
Clinical Validation
The pace at which additional data from the SENTRY trial will be presented at medical meetings and published in peer-reviewed journals.

Related topics

Drug Development