BlossomHill Therapeutics, Inc.

Exhibit 99.1 BlossomHill Therapeutics Reports Third Quarter 2026 Financial Results and Recent Business Highlights Alignment with the US Food and Drug Administration (FDA) on 50 mg twice daily as the recommended Phase 2 dose for BH-30643 based on favorable PK, safety, and efficacy data to date Announced SOLARA-2, the single-arm pivotal Phase 2 portion of the SOLARA trial, designed with registrational intent to evaluate BH-30643 in patients with EGFR C797S-positive NSCLC; expect to dose first p…

8-K · 2026-11-12 · 0001193125-26-458447

EX-99.1 2 d266261dex991.htm EX-99.1 EX-99.1 Exhibit 99.1 BlossomHill Therapeutics Reports Second Quarter 2026 Financial Results Strengthened balance sheet with successful completion of upsized $168.3 million initial public offering Announced FDA Fast Track designation for BH-30643 for the treatment of advanced EGFR C797S-positive NSCLC SAN DIEGO, September 18, 2026 - BlossomHill Therapeutics, Inc. (Nasdaq: BLSM), a clinical-stage biopharmaceutical company applying an intentional, chemi…

8-K · 2026-09-18 · 0001193125-26-395031

EX-99.1 2 d168153dex991.htm EX-99.1 EX-99.1 Exhibit 99.1 BlossomHill Therapeutics Presents Updated Data from Ongoing Phase 1/2 SOLARA Trial Demonstrating Encouraging Anti-Tumor Activity of OMNI-EGFR ™ Inhibitor BH-30643 in EGFR C797S-Positive NSCLC at IASLC 2026 World Conference on Lung Cancer 45% objective response rate and 88% disease control rate observed in patients with EGFR C797S-positive resistance to prior EGFR inhibitors, with or without concurrent T790M, a difficult-to-treat…

8-K · 2026-09-15 · 0001193125-26-391328

E XHIBIT 99.1 Joint Filing Agreement The undersigned acknowledge and agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13G shall be filed on behalf of each of the undersigned without the necessity of filing additional joint filing statements. The undersigned acknowledge that each shall be responsible for the timely filing of such amendments, and for the completeness and accuracy of t…

SCHEDULE 13G · 2026-08-17 · 0001213900-26-090726

Exhibit 10.7 B LOSSOM H ILL T HERAPEUTICS, I NC. N ON -E MPLOYEE D IRECTOR C OMPENSATION P OLICY A DOPTED : J UNE 25, 2026 Each member of the Board of Directors (the “Board”) of BlossomHill Therapeutics, Inc. (the “Company”) who is not also serving as an employee of or consultant to the Company or any of its subsidiaries (each such member, an “Eligible Director”) will receive the compensation described in this Non-Employee Director Compensation Policy (this “Policy”) for his or her Board ser…

S-1/A · 2026-08-03 · 0001193125-26-329416

Exhibit 4.1 CUSIP/IDENTIFIER XXXXXX XX X Holder ID XXXXXXXXXX Insurance Value 1,000,000.00 Number of Shares 123456 DTC 12345678 123456789012345 PO Box 43004, Providence RI 02940-3004 Certificate Numbers Num/No. Denom. Total MR A SAMPLE 1234567890/1234567890 1 1 1 DESIGNATION (IF ANY) 1234567890/1234567890 2 2 2 ADD 1 1234567890/1234567890 3 3 3 ADD 2 ADD 3 1234567890/1234567890 4 4 4 ADD 4 1234567890/1234567890 5 5 5 1234567890/1234567890 6 6 6 Total Transaction 7 ZQ|CERT#|COY|CLS|RGSTRY|ACCT#|…

S-1/A · 2026-08-03 · 0001193125-26-329416