{"schema_version":"secwatch.filing_event.v1","accession":"0001999480-25-000053","form_type":"8-K","ticker":"ANRO","cik":"0001999480","company_name":"Alto Neuroscience, Inc.","filed_at":"2025-06-26T23:59:59+00:00","discovered_at":"2026-05-14T18:02:50.661914+00:00","generated_at":"2026-05-18T18:30:31.498176+00:00","sec_items":["8.01","9.01"],"event_type":"other_material","sentiment":"positive","materiality_score":0.65,"calibrated_materiality_score":0.65,"confidence":"high","headline":"Alto Neuroscience identifies EEG biomarker and positive Phase 2 results for ALTO-203 in MDD","bullets":["ALTO-203 showed pro-cognitive and wake-promoting effects; EEG theta/beta ratio confirmed as key biomarker (25µg: p<0.05).","Improvements in sustained attention replicated Phase 1 findings; greatest in patients with high baseline theta/beta ratio (25µg: p<0.01; 75µg: p<0.05).","Objective sleep measures from wearables confirmed wake-promotion; both doses significant (25µg: p<0.05; 75µg: p<0.001 vs placebo).","MADRS improvements were small (25µg: -2 points at week 3 vs placebo) but trial not powered for significance.","Safety profile: well tolerated, insomnia most common adverse event; predictable PK."],"urls":{"canonical":"https://secwatch.observer/filing/0001999480-25-000053","json":"https://secwatch.observer/filing/0001999480-25-000053.json","markdown":"https://secwatch.observer/filing/0001999480-25-000053.md","text":"https://secwatch.observer/filing/0001999480-25-000053.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1999480/000199948025000053/0001999480-25-000053-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1999480/000199948025000053/alto-20250626.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-18T18:30:31.498176+00:00"},"review":{"review_status":"machine_generated","human_reviewed":false,"corrected":false,"correction_note":null,"correction_timestamp":null,"superseded_by":null,"related_filings":[]},"source_grounded_claims":[],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}