{"schema_version":"secwatch.filing_event.v1","accession":"0000950170-25-113553","form_type":"8-K","ticker":"RARE","cik":"0001515673","company_name":"Ultragenyx Pharmaceutical Inc.","filed_at":"2025-09-08T23:59:59+00:00","discovered_at":"2026-05-14T18:02:44.188745+00:00","generated_at":"2026-05-17T07:33:57.911953+00:00","sec_items":["8.01"],"event_type":"other_material","sentiment":"positive","materiality_score":0.8,"calibrated_materiality_score":0.8,"confidence":"high","headline":"Ultragenyx reports positive longer-term Phase 3 data for DTX401 gene therapy in GSDIa","bullets":["DTX401 met primary endpoint at Week 48: mean cornstarch reduction 41% vs 10% placebo (p<0.0001).","At Week 96, DTX401 and crossover groups each achieved mean 61% reduction in daily cornstarch from baseline.","Two-thirds of participants eliminated at least one nighttime cornstarch dose; fasting tolerance improved through Year 2.","83% of DTX401 group and 95% of crossover reported improved disease burden at Week 96 per PGIC.","Open-label cohort (n=3) achieved 95% mean cornstarch reduction at Week 24; all discontinued cornstarch by Week 36."],"urls":{"canonical":"https://secwatch.observer/filing/0000950170-25-113553","json":"https://secwatch.observer/filing/0000950170-25-113553.json","markdown":"https://secwatch.observer/filing/0000950170-25-113553.md","text":"https://secwatch.observer/filing/0000950170-25-113553.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1515673/000095017025113553/0000950170-25-113553-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1515673/000095017025113553/rare-20250908.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-17T07:33:57.911953+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"}