---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-421025"
form_type: "8-K"
ticker: "KPTI"
cik: "0001503802"
company_name: "Karyopharm Therapeutics Inc."
filed_at: "2026-10-14T11:30:05+00:00"
generated_at: "2026-10-14T11:35:27.531158+00:00"
event_type: "debt"
sentiment: "negative"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "medium"
source: SEC EDGAR
---

# Karyopharm extends indenture forbearance period to Oct 22, 2026 from Oct 15

## Summary
- Company extended the end of its Forbearance Period from 11:59 p.m. ET Oct 15, 2026 to 11:59 p.m. ET Oct 22, 2026, absent earlier termination.
- Extension made under Section 19 of the Forbearance Agreement and Limited Waiver to Indentures dated Sept 10, 2026, disclosed in a Sept 11, 2026 Form 8-K.
- Filing does not specify note principal amounts, interest rates, or the underlying covenant defaults prompting forbearance.
- Signed Oct 14, 2026 by Michael Mano, Executive Vice President, Chief Legal Officer and Secretary; KPTI trades on Nasdaq.

## SEC filing metadata
- accession: 0001193125-26-421025
- form_type: 8-K
- ticker: KPTI
- cik: 0001503802
- company_name: Karyopharm Therapeutics Inc.
- filed_at: 2026-10-14T11:30:05+00:00
- event_type: debt
- sentiment: negative
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: medium
- sec_items: 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1503802/000119312526421025/0001193125-26-421025-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1503802/000119312526421025/d451522d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-421025
- JSON: https://secwatch.observer/filing/0001193125-26-421025.json
- Plain text: https://secwatch.observer/filing/0001193125-26-421025.txt

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