Karyopharm sNDA Filed for Xpovio in Myelofibrosis
Karyopharm Therapeutics has submitted a supplemental NDA seeking accelerated approval for Xpovio (selinexor) in combination with ruxolitinib for patients with myelofibrosis. Karyopharm has requested a priority review, which, if granted, could result in a six-month review.
The sNDA is based, in part, on data from the Phase 3 SENTRY trial that the company believes supports a positive benefit-risk profile for the combination, including a promising signal of overall survival. The company expects that approval under the accelerated approval pathway would require FDA to “agree that spleen volume reduction greater than 35% (SVR35) is a reasonably likely surrogate endpoint to predict overall survival.” It plans to use long-term overall survival data from the SENTRY trial to verify clinical benefit and support conversion from accelerated to traditional approval.
Xpovio is described as a first-in-class, oral exportin 1 (XPO1) inhibitor compound for treating cancer. It works by selectively binding to and inhibiting the nuclear export protein XPO1. The drug is approved in multiple oncology indications, including: (1) in combination with Velcade (bortezomib) and dexamethasone in adult patients with multiple myeloma after at least one prior therapy; and (2) in combination with dexamethasone in adult patients with heavily pre-treated multiple myeloma.
A previous accelerated approval for diffuse large B-cell lymphoma was officially withdrawn in April after the company failed to complete a confirmatory study.