---
schema_version: "secwatch.filing_event.v1"
accession: "0001714899-26-000070"
form_type: "8-K"
ticker: "DNLI"
cik: "0001714899"
company_name: "Denali Therapeutics Inc."
filed_at: "2026-05-21T22:17:45+00:00"
generated_at: "2026-05-22T10:10:12.641230+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Denali & Biogen halt BIIB122 in idiopathic Parkinson's after Phase 2b miss; BEACON continues

## Summary
- Phase 2b LUMA study of BIIB122 (DNL151) in 648 early-stage Parkinson's patients failed primary and secondary endpoints.
- BIIB122 did not slow disease progression vs placebo on MDS-UPDRS Part II+III combined score.
- Biogen and Denali discontinue further development of BIIB122 in idiopathic Parkinson's disease.
- Denali continues independent Phase 2a BEACON study in LRRK2 pathogenic variant carriers; data expected H1 2027.
- Biomarker data showed >90% peripheral LRRK2 kinase inhibition and ~30% CSF pRab10 reduction.

## SEC filing metadata
- accession: 0001714899-26-000070
- form_type: 8-K
- ticker: DNLI
- cik: 0001714899
- company_name: Denali Therapeutics Inc.
- filed_at: 2026-05-21T22:17:45+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1714899/000171489926000070/0001714899-26-000070-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1714899/000171489926000070/dnli-20260521.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001714899-26-000070
- JSON: https://secwatch.observer/filing/0001714899-26-000070.json
- Plain text: https://secwatch.observer/filing/0001714899-26-000070.txt

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