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 patient in Q1 2027

Collaboration with Foundation Medicine to develop a companion diagnostic assay for the EGFR C797S resistance mutation

$224.9 million in cash and cash equivalents as of September 30, 2026

SAN DIEGO, Nov. 12, 2026 (GLOBE NEWSWIRE) -- 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 third quarter 2026 and highlighted recent progress.

"We are pleased to have aligned with the FDA on a recommended Phase 2 dose of 50 mg BID based on favorable PK, safety and efficacy data in the Phase 1 portion of the SOLARA trial. We are now preparing to initiate SOLARA-2, a single arm, pivotal Phase 2 trial designed to evaluate BH-30643 in both chemotherapy-naive and chemotherapy-pretreated patients with C797S-positive NSCLC after progression on a third-generation EGFR TKI," said J. Jean Cui, Ph.D., Founder, President and Chief Executive Officer of BlossomHill Therapeutics. "In parallel, we continue to advance the development of novel, small molecule medicines in our portfolio. We recently presented preclinical data on BH-501284, our novel, pseudo-irreversible, Switch-II pan-KRAS inhibitor, that demonstrated sustained KRAS pathway suppression and deep and durable antitumor activity across multiple KRAS-mutant tumor models. An IND filing is planned for the first quarter next year. We also plan to present translational data with clinical validation of BH-30236's mechanism of action at the American Society of Hematology Annual Meeting in December, reinforcing our belief in its potential to address a significant unmet need in patients with myeloid malignancies."

Recent Business Highlights and Corporate Updates:

   -- Alignment with the FDA on 50 mg twice daily as the recommended Phase 2 
      dose based on favorable pharmacokinetic (PK), safety and efficacy data 
      from the SOLARA Phase 1 trial 
 
   -- Announced SOLARA-2, the single-arm Phase 2 portion of the SOLARA trial, 
      in patients with EGFR C797S-positive NSCLC to potentially support an 
      accelerated approval application 
 
   -- Collaboration with Foundation Medicine to develop a companion diagnostic 
      assay (CDx) for the EGFR C797S resistance mutation 
 
   -- Preclinical data on BH-501284, a novel, orally bioavailable, non-covalent, 
      pseudo-irreversible pan-KRAS inhibitor designed to overcome limitations 
      of current KRAS-targeted therapies, presented at the American Association 
      for Cancer Research (AACR) Conference on Pancreatic Cancer: New Frontiers 
      in Biology and Therapeutic Development 
 
   -- Abstract highlighting the upcoming presentation of translational data 
      providing further clinical validation of BH-30236's mechanism of action 
      at the American Society of Hematology (ASH) Annual Meeting in December 

Anticipated Upcoming Milestones:

BH-30643

   -- Q1 2027: First patient dosed in pivotal SOLARA-2 trial 
 
   -- 1H 2027: Updated Phase 1 data, including C797S durability 
 
   -- 2H 2027: Phase 1 data on TKI-naive durability and initial chemo combo 
      cohort data 

BH-501284

   -- Q1 2027: Investigational new drug application (IND) submission 

BH-30236

   -- 1H 2027: Updated Phase 1 data on safety and anti-leukemic effect 

Third Quarter 2026 Financial Results

Research and development (R&D) expenses for the third quarter of 2026 were $21.9 million, compared with $14.7 million for the same period in 2025. The increase of $7.3 million was primarily due to greater clinical development expenses related to BH-30643, increased personnel-related expenses driven by R&D headcount growth, and greater expenses related to IND-enabling work for BH-501284.

General and administrative (G&A) expenses for the third quarter of 2026 were $3.6 million, compared with $2.1 million for the same period in 2025. The increase of $1.5 million was primarily due to increased personnel-related expenses, greater general overhead and outside services expenses, and an increase in legal expenses.

Net loss for the third quarter of 2026 was $24.0 million, or ($1.29) per basic and diluted share, compared with $16.0 million, or ($6.54) per basic and diluted share for the same period in 2025. The increase in net loss was primarily attributable to increased operating expenses, partially offset by an increase in other income.

Cash and cash equivalents totaled $224.9 million as of September 30, 2026. BlossomHill 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 September 30, 2026, 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(TM) 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 with ongoing Phase 1 dose expansion cohorts enrolling in both TKI-pretreated and TKI-naive settings, including a C797S resistance cohort. SOLARA-2, a global Phase 2 pivotal study in C797S-Positive NSCLC is scheduled to dose the first patient in the first quarter of 2027. For additional information on SOLARA, including a list of study sites and how to enroll, please visit clinicaltrials.gov (NCT06706076).

About BH-30236

BH-30236 is an investigational orally bioavailable, macrocyclic inhibitor of the CDC-like kinase (CLK) family. BH-30236 was intentionally designed to potently inhibit CLK, leading to modulation of aberrant alternative splicing in cancerous tissue, targeting the same aberrant splicing machinery that drives relapsed or refractory (R/R) acute myeloid leukemia (AML) and higher-risk myelodysplastic syndromes (HR-MDS) disease biology and that cancer cells exploit to develop resistance to venetoclax, FLT3 inhibitors and cytarabine. BH-30236 is being evaluated in a Phase 1/1b multicenter, open-label, first-in-human dose escalation and expansion trial in adults with R/R AML and HR-MDS. The U.S. Food and Drug Administration (FDA) has granted orphan drug designation to BH-30236 for the treatment of AML. For additional information on this trial, including a list of study sites and how to enroll, please visit clinicaltrials.gov (NCT06501196).

About BH-501284

BH-501284 is an investigational, orally bioavailable, pan-KRAS inhibitor, which utilizes a novel Switch-II chemical scaffold to achieve prolonged, potent and selective inhibition of KRAS mutations. We believe this molecule, which uses a non-covalent scaffold, is unique in its potential to achieve tight and durable binding, a feature described as "pseudo-irreversible" binding. In preclinical studies, BH-501284 demonstrated sustained blocking of KRAS signaling leading to deeper and more durable antitumor activities in KRAS mutant cells and tumor models at low dose levels.

About BlossomHill Therapeutics

BlossomHill Therapeutics, Inc. is a clinical-stage biopharmaceutical company applying an intentional, chemistry-based approach to design and develop innovative small molecule medicines that address significant unmet medical needs in cancer treatment. Founded and led by industry veteran J. Jean Cui, Ph.D., with her proven track record in oncology drug design and development -- including three FDA-approved drugs -- BlossomHill Therapeutics applies cutting-edge science with a goal to address key oncogenic drivers and improve patient outcomes in difficult-to-treat cancers. The company's lead clinical program is BH-30643, an investigational, novel, orally bioavailable, non-covalent, macrocyclic, brain active, mutant-selective OMNI-EGFR(TM) inhibitor for the treatment of EGFR-mutant non-small cell lung cancer (NSCLC), has received Fast Track designation for the C797S resistance population after 3rd generation EGFR TKI treatment. The company is also conducting clinical development of BH-30236, an investigational macrocyclic CDC-like kinase (CLK) inhibitor initially being studied in a clinical trial for the treatment of relapsed or refractory acute myeloid leukemia (R/R AML) and higher-risk myelodysplastic syndromes (HR-MDS). The company's pipeline also includes BH-501284, a preclinical, non-covalent, selective, pan-KRAS Switch-II inhibitor for potential future development in diverse KRAS-mutant tumors.

BlossomHill Therapeutics is headquartered in San Diego, California. For more information, visit www.bhtherapeutics.com and follow us on LinkedIn and X.

Cautionary Note Regarding Forward-Looking Statements