US pharmaceutical company Karyopharm Therapeutics Inc. (NASDAQ: KPTI) said on Monday it has submitted a supplemental New Drug Application to the US Food and Drug Administration for Accelerated Approval of XPOVIO (selinexor) combined with ruxolitinib in myelofibrosis.

The Company has also requested Priority Review, which could shorten the process to six months.

The filing follows top-line Phase 3 SENTRY trial results and ongoing FDA engagement. Karyopharm said the application is supported by data indicating rapid and sustained spleen responses and a signal of overall survival benefit. It expects the FDA to assess whether spleen volume reduction of at least 35% is a suitable surrogate endpoint for Accelerated Approval.

Karyopharm plans to use long-term overall survival data from SENTRY to confirm clinical benefit and support conversion to traditional approval. The Company anticipates a decision on filing acceptance and review timelines in the fourth quarter of 2026, after the FDA's 60-day review period.

The Phase 3 SENTRY trial enrolled 353 JAK inhibitor-naïve patients and compared weekly selinexor plus ruxolitinib with placebo plus ruxolitinib. Co-primary endpoints were spleen volume reduction and symptom score change at 24 weeks.

XPOVIO is a first-in-class oral exportin 1 inhibitor marketed in the US for multiple myeloma and approved in more than 50 ex-US territories. It has received Orphan Drug Designation in the US and Europe and Fast Track Designation in the US for multiple myelofibrosis settings.