---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-22-011935"
form_type: "8-K"
ticker: "LONA"
cik: "0001620463"
company_name: "LeonaBio, Inc."
filed_at: "2022-06-22T23:59:59+00:00"
generated_at: "2026-06-25T00:00:03.242689+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Athira Phase 2 ACT-AD misses primary endpoint; monotherapy subgroup shows cognitive benefit

## Summary
- Primary endpoint ERP P300 latency not statistically significant in full mITT population (-6.02 ms vs placebo).
- Pre-specified subgroup: combination with AChEIs diminished fosgonimeton effect; post hoc monotherapy showed ERP P300 improvement of -28 ms and ADAS-Cog11 -3.3 points.
- Fosgonimeton well tolerated; no treatment-related SAEs or deaths; injection site reaction most common AE.
- Study enrolled 77 patients; 14% early termination rate; results to inform ongoing Phase 3 LIFT-AD (NCT04488419).
- Management plans to seek regulatory advice on potential adaptations to LIFT-AD based on these findings.

## SEC filing metadata
- accession: 0000950170-22-011935
- form_type: 8-K
- ticker: LONA
- cik: 0001620463
- company_name: LeonaBio, Inc.
- filed_at: 2022-06-22T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 8.01, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1620463/000095017022011935/0000950170-22-011935-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1620463/000095017022011935/atha-20220622.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-22-011935
- JSON: https://secwatch.observer/filing/0000950170-22-011935.json
- Plain text: https://secwatch.observer/filing/0000950170-22-011935.txt

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