Shares of Karyopharm Therapeutics rose in pre-market trading after the company said it has submitted a supplemental New Drug Application to the U.S. Food and Drug Administration for Accelerated Approval of XPOVIO (selinexor) in combination with ruxolitinib to treat patients with myelofibrosis. The filing includes a request for Priority Review, which—if granted—could shorten the agency’s timetable and support a faster path to regulatory consideration.
According to the company, the supplemental NDA (sNDA) is based in part on data from the SENTRY trial. Karyopharm expects to receive notice from the FDA on whether the sNDA is accepted and, if accepted, the anticipated review schedule in the fourth quarter of 2026 after the standard 60-day filing review period.
Key takeaways
- Price move: Karyopharm shares were up 3.74% in pre-market trading to $1.94.
- Catalyst: The company filed an sNDA with the FDA seeking Accelerated Approval for selinexor (XPOVIO) plus ruxolitinib in myelofibrosis.
- Regulatory focus: Karyopharm requested Priority Review, which could reduce the standard review duration if approved.
- Timeline: The company expects an FDA decision on acceptance and review timing in the fourth quarter of 2026, following the 60-day filing review period.
- Implication: A positive acceptance outcome could move the drug combination closer to a potential label expansion, contingent on subsequent FDA review.
What drove the move
Karyopharm said it has submitted the supplemental NDA for Accelerated Approval of XPOVIO (selinexor) combined with ruxolitinib in patients with myelofibrosis. The company also requested Priority Review, indicating an effort to accelerate FDA evaluation if the application meets the agency’s criteria for shortened review timelines.
In its filing, Karyopharm noted that the sNDA is supported, at least in part, by data from the SENTRY trial. For investors, that linkage to existing clinical data is a key element, as it may reduce uncertainty compared with proposals that rely heavily on new, unpublished studies—though further outcomes still depend on the FDA’s assessment of the evidence provided.
Market reaction and what investors are watching
In pre-market trading on NasdaqGS, Karyopharm’s shares were up 3.74% to $1.94, reflecting early enthusiasm around the regulatory milestone. Moves like this typically signal that investors view the filing as progress toward expanding treatment options in myelofibrosis and potentially strengthening the commercial outlook for the combination therapy if approval follows.
Still, near-term expectations are tightly tied to procedural steps. The company said it expects notice regarding the FDA’s decision on sNDA acceptance and the anticipated review timelines after the 60-day filing review period. Acceptance matters because an FDA decision that the application is sufficiently complete can set the stage for formal substantive review; conversely, non-acceptance could delay the timetable or require additional information.
Bigger picture for the company and the therapy
The submission underscores Karyopharm’s continued emphasis on bringing XPOVIO earlier and more broadly into treatment strategies for serious hematologic conditions. Myelofibrosis remains an area where regulators and patients closely monitor the balance between efficacy and safety, especially in combination regimens.
Requested Priority Review, if granted, would compress the review process to about six months, according to the company’s description. That potential acceleration could be particularly relevant for investors tracking how quickly the FDA could deliver a regulatory decision after the agency acknowledges the filing.
However, the path from sNDA submission to approval still depends on the agency’s evaluation of the submitted clinical and regulatory package. Accelerated Approval is contingent on the FDA’s determination that the provided evidence supports the intended benefit and regulatory standards for that pathway.
What to watch next
Karyopharm’s next major milestone is the FDA’s communication on whether it accepts the supplemental NDA and the resulting review timeline, which the company expects in the fourth quarter of 2026 after the 60-day filing review period. Investors will likely focus on any updates related to Priority Review status and subsequent FDA actions once the application enters the agency’s formal review window.
