secwatch.observer — SEC 8-K summary
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Issuer:     Summit Therapeutics Inc. (SMMT)
CIK:        0001599298
Form:       8-K
Filed at:   2026-09-15T12:44:39+00:00
Accession:  0001599298-26-000081
Event type: other_material
Sentiment:  positive
Materiality: 0.85
Item codes: 8.01, 9.01
LLM model:  deepseek-v4-flash:cloud@v2

Summit reports consistent OS benefit for ivonescimab in HARMONi; HARMONi-2 OS data positive
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- Updated HARMONi OS analysis: global ITT HR 0.76 (95% CI 0.61-0.95; p=0.0151), median OS 16.8 vs 14.0 months.
- Western subgroup OS HR 0.76 (95% CI 0.52-1.10), consistent with global; median follow-up 23.2 months.
- HARMONi-2 (Akeso-sponsored) OS: HR 0.73 (95% CI 0.57-0.95; p=0.009) vs pembrolizumab; median OS 30.8 vs 22.6 months.
- No new safety signals; BLA PDUFA date for ivonescimab is November 14, 2026.

Source:
  EDGAR index:    https://www.sec.gov/Archives/edgar/data/1599298/000159929826000081/0001599298-26-000081-index.htm
  Primary doc:    https://www.sec.gov/Archives/edgar/data/1599298/000159929826000081/smmt-20260915.htm
  HTML page:      https://secwatch.observer/filing/0001599298-26-000081

License: Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer