---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-391328"
form_type: "8-K"
ticker: "BLSM"
cik: "0001839970"
company_name: "BlossomHill Therapeutics, Inc."
filed_at: "2026-09-15T11:30:06+00:00"
generated_at: "2026-09-15T11:35:08.835051+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# BlossomHill reports 45% ORR for BH-30643 in EGFR C797S-positive NSCLC from SOLARA trial

## Summary
- ORR 45% (18/40) and DCR 88% (35/40) in EGFR C797S-positive NSCLC patients with prior EGFR inhibitor resistance, ± T790M.
- 63% (25/40) remained on treatment at median follow-up 6.9 months; 98% had prior osimertinib, 35% concurrent T790M.
- Safety (n=174, 40/50/60 mg BID): treatment-related dose reductions 9%, discontinuations 3%; common AE bilirubin elevation.
- Plans global Phase 2 targeting EGFR C797S-positive NSCLC in Q1 2027; FDA Fast Track designation previously granted.
- Activity seen across pretreated population: median 2 prior lines; 53% prior chemo/ADC; 53% history of brain metastases.

## SEC filing metadata
- accession: 0001193125-26-391328
- form_type: 8-K
- ticker: BLSM
- cik: 0001839970
- company_name: BlossomHill Therapeutics, Inc.
- filed_at: 2026-09-15T11:30:06+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1839970/000119312526391328/0001193125-26-391328-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1839970/000119312526391328/d168153d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-391328
- JSON: https://secwatch.observer/filing/0001193125-26-391328.json
- Plain text: https://secwatch.observer/filing/0001193125-26-391328.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.