{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-25-184706","form_type":"8-K","ticker":"SEPN","cik":"0001984086","company_name":"Septerna, Inc.","filed_at":"2025-08-21T23:59:59+00:00","discovered_at":"2026-05-14T18:02:45.761262+00:00","generated_at":"2026-05-17T10:57:52.844850+00:00","sec_items":["7.01","9.01"],"event_type":"other_material","sentiment":"neutral","materiality_score":0.5,"calibrated_materiality_score":0.5,"confidence":"high","headline":"Septerna doses first participants in Phase 1 trial of SEP-631 for mast cell-driven diseases","bullets":["SEP-631 is an oral small molecule MRGPRX2 negative allosteric modulator (NAM) targeting chronic spontaneous urticaria (CSU) and other mast cell-driven diseases.","Phase 1 SAD/MAD trial will evaluate safety, tolerability, PK and PD in up to ~150 healthy volunteers; SAD dosing is underway.","PD assessed via icatibant skin challenge in the MAD portion; no financial or guidance updates provided.","Septerna highlights unmet need in CSU where many patients do not respond to antihistamines."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-25-184706","json":"https://secwatch.observer/filing/0001193125-25-184706.json","markdown":"https://secwatch.observer/filing/0001193125-25-184706.md","text":"https://secwatch.observer/filing/0001193125-25-184706.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1984086/000119312525184706/0001193125-25-184706-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1984086/000119312525184706/d51455d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-17T10:57:52.844850+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"}