BlossomHill（BLSM）WCLC公布BH-30643治疗EGFR C797S阳性NSCLC更新数据：ORR 45%、DCR 88%，安全性良好

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM
8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported):
September 15, 2026
BlossomHill Therapeutics, Inc.
(Exact name of registrant as specified in its charter)
Delaware
001-43435
85-1578711
(State or other jurisdiction
of incorporation)
(Commission
File Number)
(IRS Employer
Identification No.)
10255 Science Center Drive
Suite 200
San Diego
,
California
92121
(Address of principal executive offices)
Registrant’s telephone number, including area code:
(858)
732-3880
N/A
(Former name or former address, if changed since last report.)
Check the appropriate box below if the Form
8-K
filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
☐
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐
Soliciting material pursuant to Rule
14a-12
under the Exchange Act (17 CFR
240.14a-12)
☐
Pre-commencement
communications pursuant to Rule
14d-2(b)
under the Exchange Act (17 CFR
240.14d-2(b))
☐
Pre-commencement
communications pursuant to Rule
13e-4(c)
under the Exchange Act (17 CFR
240.13e-4(c))
Securities registered pursuant to Section 12(b) of the Act:
Title of each class
Trading
Symbol(s)
Name of each exchange
on which registered
Common Stock, $0.0001 par value per share
BLSM
The Nasdaq Global Select Market
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule
12b-2
of the Securities Exchange Act of 1934
(§240.12b-2
of this chapter).
Emerging growth company
☒
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
☐
Item 7.01
Regulation FD Disclosure.
On September 15, 2026, BlossomHill Therapeutics, Inc. issued a press release announcing updated data from the ongoing Phase 1/2 SOLARA trial of
BH-30643
in
non-small
cell lung cancer (NSCLC) patients with secondary epidermal growth factor receptor (EGFR) resistance mutations such as EGFR C797S. The data were highlighted in a mini-oral presentation at the International Association for the Study of Lung Cancer (IASLC) 2026 World Conference on Lung Cancer in Seoul, South Korea. The full text of the press release issued in connection with this announcement is furnished as Exhibit 99.1 to this Current Report on Form
8-K.
The information in this Item 7.01 and the attached Exhibit 99.1 is being furnished and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section. The information in this Item 7.01 and the attached Exhibit 99.1 shall not be incorporated by reference into any registration statement or other document pursuant to the Securities Act of 1933, as amended.
Item 9.01
Financial Statements and Exhibits.
(d) Exhibits.
Exhibit
No.
Description
99.1
Press Release, dated September 15, 2026.
104
Cover Page Interactive Data File (embedded within the Inline XBRL document).
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
BlossomHill Therapeutics, Inc.
Dated: September 15, 2026
By:
/s/ J. Jean Cui, Ph.D.
J. Jean Cui, Ph.D.
President and Chief Executive Officer

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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
population with no
approved targeted therapies
BH-30643
demonstrated a favorable safety profile with low rates
of dose reduction or
discontinuation due to treatment-related adverse events
Presentation follows receipt of FDA Fast Track designation for
BH-30643
for the treatment of
advanced or metastatic EGFR C797S-positive NSCLC
SAN DIEGO, September
15, 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 updated data from the ongoing Phase 1/2 SOLARA trial of
BH-30643
in
non-small
cell lung cancer (NSCLC) patients with secondary
epidermal growth factor receptor
(
EGFR
) resistance mutations such as EGFR C797S. The data
were highlighted in a mini-oral presentation at the International Association for the Study of Lung Cancer (IASLC) 2026 World Conference on Lung Cancer in Seoul, South Korea.
BH-30643
is an investigational, novel, orally bioavailable,
non-covalent,
macrocyclic, brain active, mutant-selective, OMNI-EGFR
™
inhibitor designed to overcome the limitations of currently approved EGFR inhibitors for the treatment of
EGFR
-mutant NSCLC. In
patients with EGFR C797S-positive resistance to prior EGFR inhibitor treatment, with or without concurrent T790M,
BH-30643
demonstrated a 45% objective response rate (ORR; 18/40) and an 88% disease control
rate (DCR; 35/40). At the time of efficacy
follow-up,
63% (25/40) of patients remained on treatment with a median
follow-up
of 6.9 months.
BH-30643
also demonstrated a favorable safety profile with low rates of dose reduction or discontinuation due to treatment-related adverse events.
“C797S-driven resistance to third-generation EGFR inhibitors was first described over 10 years ago, yet patients whose tumors develop this mutation
currently have no approved targeted treatment options,” said Hidehito Horinouchi, M.D., Ph.D., National Cancer Center Hospital, Tokyo, and presenting author of the study. “The responses observed with
BH-30643
in this heavily pretreated population, together with encouraging early evidence of durability, support the potential of
BH-30643
to directly target this
resistance mechanism. These results are particularly encouraging given the need for new precision treatment options that can extend the benefits of targeted therapy for patients with
EGFR
-mutant lung cancer.”
“These updated results provide important clinical validation of the approach we took in intentionally designing
BH-30643
to address
on-target
EGFR resistance, including C797S,” said Geoff Oxnard, M.D., Chief Medical Officer of BlossomHill Therapeutics. “We are
encouraged to see meaningful anti-tumor activity across a molecularly diverse group of patients with C797S-positive disease, including patients with concurrent T790M and those who have received multiple prior therapies, with a favorable safety
profile. Together with the recent FDA Fast Track designation, these data strengthen our conviction in the potential of
BH-30643
and support our plans to advance into a Phase 2 trial in patients with
C797S-positive NSCLC in 2027.”
Presentation highlights:
As of the May 12, 2026 data cutoff, with efficacy
follow-up
through August 10, 2026:
•
Encouraging anti-tumor activity was observed in patients with C797S-positive resistance.
Among 40 patients
with EGFR C797S-positive resistance to prior EGFR inhibitor treatment, with or without concurrent T790M, 18 patients achieved a confirmed (16) or ongoing unconfirmed (2) partial response, representing an ORR of 45% (95% CI:
29%-62%).
The DCR was 88% (35/40), and 25 patients (63%) remained on treatment at the time of efficacy
follow-up.
Median
follow-up
was
6.9 months.
•
Activity was observed across a clinically heterogeneous, previously treated population.
Patients had
received a median of two prior lines of therapy; 98% had received prior osimertinib, 53% had received prior chemotherapy and/or an antibody-drug conjugate, and 53% had a history of brain metastases. 35% of patients had concurrent T790M.
•
BH-30643
demonstrated a favorable safety profile at expansion
doses.
Among 174 patients treated at doses of 40 mg, 50 mg and 60 mg twice daily, treatment-related dose reductions and discontinuations occurred in 9% and 3% of patients, respectively. EGFR wild-type-associated treatment-related adverse events
were primarily Grade 1. The most common treatment-related adverse event was bilirubin elevation, which was generally asymptomatic and predominantly unconjugated, consistent with UGT1A1 inhibition by
BH-30643.
•
Development of
BH-30643
is continuing across multiple
EGFR
-mutant populations.
Expansion cohorts are evaluating
on-target
resistance mutations, targeted therapy-naive patients and
BH-30643
in
combination with chemotherapy. BlossomHill plans to initiate a global Phase 2 study targeting
EGFR
C797S-positive NSCLC in Q1 2027.
The presentation is available on the company’s Posters & Presentations page here:
https://bhtherapeutics.com/pipeline/#posters-and-presentations
.
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
).
About the SOLARA Trial
The Phase 1/2 SOLARA clinical trial (
NCT06706076
) is a global, open label, multicenter study assessing the safety, tolerability, pharmacokinetics,
pharmacodynamics and preliminary anti-tumor activity of
BH-30643
in patients with epidermal growth factor receptor (EGFR) mutant
non-small
cell lung cancer (NSCLC).
Phase 1 will determine the recommended Phase 2 dose (RP2D) of
BH-30643
as a monotherapy and in combination with chemotherapy. Phase 2 is designed to evaluate the antitumor efficacy and safety in specified
cohorts determined by mutation subtypes and/or treatment history at the RP2D, as well as the population pharmacokinetics.
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,
non-covalent,
macrocyclic, brain active, mutant-selective OMNI-EGFR
TM
inhibitor for the treatment of EGFR-mutant
non-small
cell lung cancer (NSCLC), which 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
bhtherapeutics.com
and follow us
on
LinkedIn
and
X
.
Cautionary Note Regarding Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, and other
federal securities laws, including, without limitation, statements regarding: the therapeutic potential, clinical benefits, safety and potential competitive differentiation of the company’s product candidates, including
BH-30643,
BH-30236
and
BH-501284;
the anticipated benefits of regulatory designations received, or that may be received, by the
company’s product candidates; the design, enrollment, timing, progress and results of the company’s clinical trials and preclinical studies; the company’s planned regulatory interactions and submissions; anticipated program
milestones, announcements and updates, including the initiation of the Phase 2 study for
BH-30643
in Q1 2027; statements by the company’s management; and the company’s development plans and
continued advancement of its pipeline. The words “anticipate,” “believe,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,”
“potential,” “predict,” “project,” “should,” “target,” “upcoming,” “will,” “would” and similar expressions are intended to identify forward-looking
statements, although not all forward-looking statements contain these identifying words.
Any forward-looking statements in this press release are
based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially, including, without limitation: the company’s
limited operating history, history of significant losses and the early stage of development of its product candidates; the risk that preliminary and
interim clinical data are subject to further analysis and may not be predictive of, may be inconsistent with, or may be more favorable than, data generated as clinical trials continue or data
from future clinical trials; uncertainties inherent in the initiation, timing, design and enrollment of clinical trials, and the availability and timing of data from ongoing and future trials; the company’s ability to successfully demonstrate
the safety and efficacy of its product candidates and to obtain and maintain regulatory approvals; the timing and outcome of planned interactions with, and submissions to, the FDA and other regulatory authorities, including whether an accelerated
approval pathway will be available to the company; the risk that regulatory designations, including Fast Track and orphan drug designation, may not result in a faster development, review or approval process, do not increase the likelihood of
regulatory approval, and may be withdrawn; competition from third parties that are developing products for similar indications; the prior success of the company’s management team not being indicative of future success; the company’s
reliance on third parties, including contract research organizations and contract manufacturing organizations; the company’s ability to obtain, maintain and protect its intellectual property; and the company’s need for additional
financing and its estimates regarding operating expenses and capital requirements. These and other risks are described in greater detail under the heading “Risk Factors” in the company’s final prospectus filed with the Securities
and Exchange Commission (the “SEC”) on August 7, 2026 pursuant to Rule 424(b)(4) under the Securities Act of 1933, as amended, as well as in the company’s subsequent filings with the SEC. Any forward-looking statements
represent the company’s views only as of the date of this press release, and the company expressly disclaims any obligation to update any forward-looking statements, except as required by law.
Company Contact:
Michael Moore, BlossomHill Therapeutics
michael.moore@bhtherapeutics.com
Media:
Ashlea Kosikowski, 1AB
ashlea@1abmedia.com