---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-26-038593"
form_type: "8-K"
ticker: "ANRO"
cik: "0001999480"
company_name: "Alto Neuroscience, Inc."
filed_at: "2026-04-01T23:59:59+00:00"
generated_at: "2026-05-15T08:02:35.830781+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# Alto Neuroscience Phase 2 miss for ALTO-101; shifts focus to ALTO-207

## Summary
- ALTO-101 did not meet primary EEG or cognitive endpoints in Phase 2 CIAS study.
- Near-significant theta-ITC effect (p=0.052); nominal in cognitively impaired subgroup (p=0.03).
- Company developed modified-release ALTO-101 formulation; will pursue partnerships, not further internal development.
- ALTO-207 Phase 2b in treatment-resistant depression on track for 1H 2026; cash position $275M.
- Tolerability favorable with nausea/vomiting in line with placebo; high skin reaction rates observed.

## SEC filing metadata
- accession: 0001104659-26-038593
- form_type: 8-K
- ticker: ANRO
- cik: 0001999480
- company_name: Alto Neuroscience, Inc.
- filed_at: 2026-04-01T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1999480/000110465926038593/0001104659-26-038593-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1999480/000110465926038593/tm2610746d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-26-038593
- JSON: https://secwatch.observer/filing/0001104659-26-038593.json
- Plain text: https://secwatch.observer/filing/0001104659-26-038593.txt

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