---
schema_version: "secwatch.filing_event.v1"
accession: "0001140361-26-028092"
form_type: "8-K"
ticker: "IONS"
cik: "0000874015"
company_name: "IONIS PHARMACEUTICALS INC"
filed_at: "2026-07-09T18:55:22+00:00"
generated_at: "2026-07-09T18:56:04.870561+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Ionis eplontersen Phase 3 ATTR-CM trial misses primary endpoint; monotherapy subgroup shows nominal benefit

## Summary
- CARDIO-TTRansform trial did not meet primary composite endpoint of CV mortality and recurrent CV events vs placebo at Week 140.
- In prespecified subgroup, eplontersen monotherapy showed nominally significant HR of 0.71 on the composite outcome.
- 57% of patients on stabilizer at baseline; no treatment effect observed in that subgroup.
- Secondary, imaging, and biomarker analyses favored eplontersen; safety profile consistent with prior results.
- Full results to be presented at ESC Congress in August 2026; Ionis and AstraZeneca continue analysis.

## SEC filing metadata
- accession: 0001140361-26-028092
- form_type: 8-K
- ticker: IONS
- cik: 0000874015
- company_name: IONIS PHARMACEUTICALS INC
- filed_at: 2026-07-09T18:55:22+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/874015/000114036126028092/0001140361-26-028092-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/874015/000114036126028092/ef20077664_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001140361-26-028092
- JSON: https://secwatch.observer/filing/0001140361-26-028092.json
- Plain text: https://secwatch.observer/filing/0001140361-26-028092.txt

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