{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-26-103167","form_type":"8-K","ticker":"RARE","cik":"0001515673","company_name":"Ultragenyx Pharmaceutical Inc.","filed_at":"2026-03-12T23:59:59+00:00","discovered_at":"2026-05-14T18:02:35.289939+00:00","generated_at":"2026-05-15T13:16:19.437425+00:00","sec_items":["8.01"],"event_type":"other_material","sentiment":"positive","materiality_score":0.85,"calibrated_materiality_score":0.85,"confidence":"high","headline":"Ultragenyx DTX301 Phase 3 meets primary endpoint: 18% ammonia AUC reduction (p=0.018) in OTC deficiency","bullets":["DTX301-treated patients (n=18) showed 18% reduction in 24-hour plasma ammonia AUC vs placebo (n=19) at Week 36 (p=0.018).","8 of 9 patients with abnormal baseline ammonia reached normal levels; treated patients maintained normal ammonia despite 27% mean reduction in scavenger meds.","71% of treated patients reported much improvement on PGIC vs 0% for placebo at Week 24.","One SAE of acute hepatitis (resolved with steroids); 5 hyperammonemic crises in placebo (1 death) vs 1 in treated (no deaths).","Study continues to second primary endpoint on treatment burden; data expected H1 2027."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-26-103167","json":"https://secwatch.observer/filing/0001193125-26-103167.json","markdown":"https://secwatch.observer/filing/0001193125-26-103167.md","text":"https://secwatch.observer/filing/0001193125-26-103167.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1515673/000119312526103167/0001193125-26-103167-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1515673/000119312526103167/rare-20260312.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-15T13:16:19.437425+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"}