EX-99.1 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, chemistry-based approach to design and develop innovative small molecule medicines for the treatment of cancer, today announced financial results for the second quarter 2026 and highlighted recent progress.
“We’ve achieved meaningful progress across our pipeline, as well as our significant corporate milestones, since the beginning of the second quarter,” said Jean Cui, Ph.D., Founder, President and Chief Executive Officer of BlossomHill Therapeutics. “In April, we presented our first preclinical data from our pseudo-irreversible pan-KRAS inhibitor BH-501284, built on a novel chemical scaffold, at AACR where we highlighted the sustained target engagement leading to tumor regression at low dose levels. At ASCO in early June we presented the preliminary safety, PK and antitumor activities of BH-30643 in Phase 1 dose escalation of the SOLARA trial, along with the initial efficacy data in C797S-positive NSCLC. More recently we announced that BH-30643 received Fast Track designation, an important regulatory milestone that reflects the FDA’s recognition of the potential for this molecule. We also presented encouraging safety data and early signs of anti-leukemic activity observed with BH-30236, our novel macrocyclic CLK inhibitor, both as a monotherapy and in combination with venetoclax, at EHA in the middle of June. We are now looking forward to our end-of-phase 1 meeting with the FDA later this year. With a strong balance sheet following our successful initial public offering in August, we believe we are well positioned to deliver important clinical and regulatory milestones over the coming quarters as we continue advancing our intentionally designed medicines that address significant unmet medical needs in cancer treatment.”
Recent Business Highlights and Corporate Updates:
BH-30236 1H 2027: Updated Phase 1 data on safety and anti-leukemic effect
Second Quarter 2026 Financial Results
Research and development (R&D) expenses for the second quarter of 2026 were $21.4 million, compared with $12.5 million for the same period in 2025. The increase was primarily due to greater clinical development expenses driven by the SOLARA trial, expenses to support IND-enabling studies for BH-501284, and greater costs related to personnel, facilities and other overhead.
General and administrative (G&A) expenses for the second quarter of 2026 were $3.3 million, compared with $1.6 million for the same period in 2025. The increase was primarily due to greater legal expenses, personnel-related expenses and overhead.
Net loss for the second quarter of 2026 was $23.8 million, or $(8.75) per basic and diluted share, compared with a net loss of $13.2 million, or $(5.51) per basic and diluted share for the same period in 2025. The increase in net loss was primarily attributable to increased operating expenses.
Cash and cash equivalents totaled $95.4 million as of June 30, 2026. BlossomHill subsequently completed its IPO in August 2026 in which it sold 10,516,240 shares of its common stock, including partial exercise of the over-allotment option, for gross proceeds of $168.3 million. BlossomHill believes that its cash and cash equivalents as of June 30, 2026, together with the proceeds from its IPO, will be sufficient to fund its operations into the second quarter of 2028.
About BH-30643
BH-30643 is an investigational, novel, orally bioavailable, non-covalent, macrocyclic, brain active, mutant-selective, OMNI-EGFR inhibitor for the treatment of EGFR -mutant NSCLC. BH-30643 was designed to overcome the limitations of currently approved EGFR inhibitors, which were discovered over a decade ago without the current, modern understanding of the structure and protein dynamics of mutant EGFRs. In preclinical studies, BH-30643 demonstrated potent inhibitory activity across diverse EGFR mutation categories – classical mutations, on-target resistance mutations such as C797S with or without T790M, atypical mutations and exon 20 insertions – while maintaining marked selectivity over wild-type EGFR. BH-30643 has received Fast Track designation and is being evaluated in SOLARA, a global Phase 1/2, first-in-human clinical trial spanning more than 40 sites in 10 countries. Ongoing dose expansion cohorts are enrolling in both TKI-pretreated and TKI-naive settings, including a C797S resistance cohort. For additional information on SOLARA, including a list of study sites and how to enroll, please visit clinicaltrials.gov ( NCT06706076 ).
Cash and cash equivalents totaled $95.4 million as of June 30, 2026, and the company completed its IPO in August 2026 for gross proceeds of $168.3 million.¶6
Filing figures are from this filing. Earlier figures are from past filings.