---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-326995"
form_type: "8-K"
ticker: "KPTI"
cik: "0001503802"
company_name: "Karyopharm Therapeutics Inc."
filed_at: "2026-07-31T12:30:33+00:00"
generated_at: "2026-07-31T12:35:06.907490+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Karyopharm: Phase 3 endometrial cancer trial misses primary endpoint; plans sNDA for myelofibrosis; exploring financing

## Summary
- Phase 3 XPORT-EC-042 trial of selinexor in TP53 wild-type endometrial cancer did not meet primary endpoint of PFS; median PFS 12.75 vs 7.43 months (HR=0.76, p=0.0791).
- Company plans to submit sNDA to FDA in August 2026 seeking accelerated approval of selinexor+ruxolitinib for myelofibrosis based on SVR35 at week 24.
- FDA requested further discussion on data to support sNDA and conversion to traditional approval; company will provide additional data before submission.
- Company, with Centerview Partners, is exploring financing transactions and strategic alternatives to extend cash runway; no assurance of any transaction.

## SEC filing metadata
- accession: 0001193125-26-326995
- form_type: 8-K
- ticker: KPTI
- cik: 0001503802
- company_name: Karyopharm Therapeutics Inc.
- filed_at: 2026-07-31T12:30:33+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1503802/000119312526326995/0001193125-26-326995-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1503802/000119312526326995/d71318d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-326995
- JSON: https://secwatch.observer/filing/0001193125-26-326995.json
- Plain text: https://secwatch.observer/filing/0001193125-26-326995.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.