# EDGAR Filing Document

**Accession Number:** 0001782303
**File Stem:** 0001193125-26-097535
**Filing Date:** 2026-3
**Character Count:** 16823
**Document Hash:** 1612756322cdcf3f13e998dd2dcdcfd9
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-097535.hdr.sgml**: 20260309

**ACCESSION NUMBER**: 0001193125-26-097535

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 12

**CONFORMED PERIOD OF REPORT**: 20260303

**ITEM INFORMATION**: Results of Operations and Financial Condition

**ITEM INFORMATION**: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20260309

**DATE AS OF CHANGE**: 20260309

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Boundless Bio, Inc.
- **CENTRAL INDEX KEY:** 0001782303
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 830751369
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41989
- **FILM NUMBER:** 26733160

**BUSINESS ADDRESS:**
- **STREET 1:** 10955 ALEXANDRIA WAY
- **STREET 2:** SUITE 100
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121
- **BUSINESS PHONE:** (858) 766-9912

**MAIL ADDRESS:**
- **STREET 1:** 10955 ALEXANDRIA WAY
- **STREET 2:** SUITE 100
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92121

?xml version='1.0' encoding='ASCII'? 8-K

**UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549**

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## FORM 8-K

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**CURRENT REPORT**

**Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934**

**Date of Report (Date of earliest event reported):** March 03, 2026<br>

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Boundless Bio, Inc.

**(Exact Name of Registrant as Specified in Its Charter)**

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| | | |
|:---|:---|:---|
| Delaware | 001-41989 | 83-0751369 |
| **(State or Other Jurisdiction<br>of Incorporation)** | **(Commission File Number)** | **(IRS Employer<br>Identification No.)** |
| 10955 Alexandria Way, Suite 100, |  |  |
| San Diego**,** California |  | 92121 |
| **(Address of Principal Executive Offices)** |  | **(Zip Code)** |

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**Registrant's Telephone Number, Including Area Code:** (858) 766-9912<br>

N/A<br>

**(Former Name or Former Address, if Changed Since Last Report)**

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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:**

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| | | |
|:---|:---|:---|
| **<br>Title of each class** | **Trading<br>Symbol(s)** | **<br>Name of each exchange on which registered** |
| Common Stock, par value $0.0001 per share | BOLD | Nasdaq Global Select Market |

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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. ☐

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## Item 2.02 Results of Operations and Financial Condition.
On March 9, 2026, Boundless Bio, Inc. (the Company) issued a press release announcing its financial results for the fourth quarter and full year ended December 31, 2025. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

In accordance with General Instruction B.2 of Form 8-K, the information in this Current Report on Form 8-K, including Exhibit 99.1, shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the Exchange Act), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof and regardless of any general incorporation by reference language in any such filing, unless the Company specifically states in such filing that such information, or a portion thereof, is to be considered "filed" rather than furnished or incorporated by reference therein.

## Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangement of Certain Officers.
Effective March 3, 2026, Christine Brennan, Ph.D. notified the Company of her resignation from the Board of Directors of the Company. Dr. Brennan's resignation was made in connection with her assuming a new role at Johnson & Johnson Development Corporation, and was not the result of any disagreement with the Company, including on any matter relating to its operations, policies or practices.

## Item 9.01 Financial Statements and Exhibits.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d) Exhibits.

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| | |
|:---|:---|
| **Exhibit**<br>**Number** | **Description** |
| 99.1 | [<u>Press Release Issued on March 9, 2026</u>](bold-ex99_1.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document) |

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**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.

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| | | | |
|:---|:---|:---|:---|
|  |  |  | **BOUNDLESS BIO, INC.** |
| Date: | March 9, 2026 | By:  | /s/ Jessica Oien |
|  |  |  | Name: Jessica Oien<br>Title: Chief Legal Officer and Corporate Secretary |

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## Exhibit 99.1

**Exhibit 99.1**

![img6362560_0.jpg](img6362560_0.jpg)

**Boundless Bio Reports Fourth Quarter** 

**and Full Year 2025 Financial Results and Business Highlights**

*KOMODO-1 first-in-human clinical trial of BBI-940 open for enrollment*

*$108 million in cash provides runway into the second half of 2028, through expected clinical proof-of-concept readout for KOMODO-1*

**SAN DIEGO, March 09, 2026** – Boundless Bio <u>(Nasdaq: BOLD)</u>, a clinical-stage oncology company interrogating extrachromosomal DNA (ecDNA) biology to deliver transformative therapies to patients with previously intractable oncogene amplified cancers, today announced financial results and business highlights for the fiscal quarter and full year ended December 31, 2025.

"With the KOMODO-1 trial of BBI-940 actively enrolling, we are excited to evaluate this potentially first-in-class oral Kinesin degrader in patients with breast cancer who are seeking new treatment options. BBI-940 is designed to disrupt ecDNA segregation and inheritance, a differentiated mechanism for targeting chromosomally unstable cancers. The Boundless team is focused on clinical execution and reaching an initial proof-of-concept readout within our existing cash runway," said Zachary Hornby, President and Chief Executive Officer of Boundless Bio.

**Business Highlights and Upcoming Milestones**

**BBI-940 novel Kinesin degrader program**

• In January 2026, the U.S. Food and Drug Administration accepted the Company's Investigational New Drug application for BBI-940, a novel, selective, oral Kinesin degrader.

• KOMODO-1 (<u>K</u>inesin <u>O</u>ral <u>Mo</u>lecular <u>D</u>egrader for <u>O</u>ncology-1), a first-in-human clinical trial of BBI-940 in patients with estrogen receptor positive and human epidermal growth factor receptor 2 negative (ER+/HER2-) breast cancer who have progressed following treatment with a cyclin-dependent kinase 4 and/or 6 (CDK4/6) inhibitor plus endocrine therapy, as well as patients with triple-negative breast cancer luminal androgen receptor subtype (TNBC-LAR), is open for enrollment.

• Boundless expects to deliver initial safety and efficacy clinical proof-of-concept data within its existing cash runway timeline.

**POTENTIATE clinical trial of BBI-355 and BBI-825**

• In January 2026, Boundless announced its intention to cease enrollment in the Phase 1/2 POTENTIATE trial evaluating the combination of BBI-355 and BBI-825 based on market considerations, available clinical data, and prioritization of its BBI-940 program.

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**Fourth Quarter and Full Year 2025 Financial Results** 

• **Cash Position:** Cash, cash equivalents, and short-term investments totaled $107.6 million as of December 31, 2025. The Company expects its cash to fund operations into the second half of 2028, through the anticipated initial clinical proof-of-concept readout from KOMODO-1.

• **Research and Development (R&D) Expenses:** R&D expenses were $9.8 million for the fourth quarter of 2025 and $44.8 million for the full year 2025, compared to $13.3 million and $55.3 million for the same periods of 2024.

• **General and Administrative (G&A) Expenses:** G&A expenses were $4.2 million for the fourth quarter of 2025 and $18.7 million for the full year 2025, compared to $5.0 million and $18.0 million for the same periods of 2024.

• **Net Loss:** Net loss totaled $12.9 million for the fourth quarter of 2025 and $58.2 million for the full year 2025, compared to $16.4 million and $65.4 million for the same periods of 2024.

**About Boundless Bio**

Boundless Bio is a clinical-stage oncology company dedicated to unlocking a new paradigm in cancer therapeutics that addresses the significant unmet need in patients with oncogene amplified tumors. Boundless Bio's research focuses on extrachromosomal DNA (ecDNA), a root cause of oncogene amplification observed in 14% to 17% of cancer patients. Boundless Bio is developing BBI-940, a potentially first-in-class, oral, selective Kinesin degrader as an ecDNA-directed therapeutic candidate (ecDTx). Boundless Bio is headquartered in San Diego, CA.

For more information, visit www.boundlessbio.com and follow us on LinkedIn and X.

**Forward-Looking Statements**

Boundless Bio (the Company) cautions you that statements contained in this press release that are not a description of historical facts are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as "anticipate," "believe," "contemplate," "continue," "could," "estimate," "expect," "intend," "may," "plan," "potential," "predict," "project," "should," "would," "target," or "will" or the negative of these terms or other similar expressions. Forward-looking statements are based on the Company's current beliefs and expectations and include but are not limited to statements regarding: the expected timing of an initial clinical proof-of-concept readout from the KOMODO-1 trial; the Company's cash runway and the sufficiency thereof to fund operations through the anticipated initial clinical proof-of-concept readout from the KOMODO-1 trial; the potential safety and therapeutic benefits of BBI-940 and other ecDTx the Company may develop in treating patients with oncogene amplified cancers; the expected benefits of the Company's portfolio prioritization, capital allocation, and revised operating plan; and the Company's potential to deliver clinically-meaningful, high-impact ecDTx for cancer patients and create long-term value for stockholders. The Company's actual results and performance may differ materially from those expressed or implied in any forward-looking statement due to substantial known and unknown risks and uncertainties, including, without limitation: potential delays in the enrollment, data readouts, or completion of clinical trials or in regulatory submissions and responses; the Company may use its capital resources sooner than it expects; the Company may be unable to obtain necessary additional funding when needed, on acceptable terms, or at all; the Company is early in its development efforts and its approach to discover and develop ecDTx to

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treat oncogene amplified cancers is novel and unproven; clinical and preclinical development of therapeutics involves a lengthy and expensive process with inherently uncertain timelines and outcomes; results from preclinical studies or early clinical trials not necessarily being predictive of future results; unexpected adverse side effects or inadequate efficacy of the Company's ecDTx that may limit their development, regulatory approval, and/or commercialization; the Company's ability to retain key personnel; the Company's dependence on third parties in connection with clinical trials, preclinical studies, and manufacturing; the Company may expend its limited resources to pursue a particular ecDTx or combination therapy and fail to capitalize on ecDTx with greater development or commercial potential; the potential for the Company's programs and prospects to be negatively impacted by developments relating to its competitors, including the results of studies or regulatory determinations relating to its competitors; regulatory and healthcare reform developments in the United States and foreign countries; disruptions in the FDA's ability to perform routine activities or function in the normal course; the Company's ability to obtain, maintain, defend, and enforce patent or other intellectual property protection for its ecDTx and technology; macroeconomic and geopolitical events and conditions, including international trade policies and tariffs; and other risks described in the Company's filings with the Securities and Exchange Commission (SEC), including under the heading "Risk Factors" in the Company's annual report on Form 10-K for the year ended December 31, 2025 and any subsequent filings with the SEC. You are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date hereof, and, except as required by law, the Company undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995.

**Investor Contacts:**

James Lee, Boundless Bio, Inc.

jlee@boundlessbio.com

Renee Leck, THRUST Strategic Communications <br>renee@thrustsc.com

**Media Contact:**

Carly Scaduto

carly@thrustsc.com

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| | | | | |
|:---|:---|:---|:---|:---|
| **BOUNDLESS BIO, INC.** | **BOUNDLESS BIO, INC.** | **BOUNDLESS BIO, INC.** | **BOUNDLESS BIO, INC.** | **BOUNDLESS BIO, INC.** |
| **Financial Information** | **Financial Information** | **Financial Information** | **Financial Information** | **Financial Information** |
| **Statements of Operations Data:** | **Three Months Ended<br>December 31,** | **Three Months Ended<br>December 31,** | **Year Ended<br>December 31,** | **Year Ended<br>December 31,** |
| &nbsp;&nbsp;(In thousands, except per share amounts) | **2025** | **2024** | **2025** | **2024** |
| Operating expenses: |  |  |  |  |
| &nbsp;&nbsp;Research and development | $9817 | $13314 | $44845 | $55267 |
| &nbsp;&nbsp;General and administrative | 4185 | 4964 | 18707 | 18000 |
| Total operating expenses | 14002 | 18278 | 63552 | 73267 |
| Loss from operations | (14002) | (18278) | (63552) | (73267) |
| Other income, net: |  |  |  |  |
| &nbsp;&nbsp;Interest income | 1117 | 1915 | 5357 | 7892 |
| &nbsp;&nbsp;Other income (expense), net |  | (85) | (2) | 12 |
| Total other income, net | 1117 | 1830 | 5355 | 7904 |
| Net loss | $(12885) | $(16448) | $(58197) | $(65363) |
| Net loss per share, basic and diluted | $(0.58) | $(0.74) | $(2.60) | $(3.85) |
| Weighted-average shares used in calculation | 22399 | 22284 | 22360 | 16984 |
| **Balance Sheet Data:** |  |  | **December 31,** | **December 31,** |
| &nbsp;&nbsp;(In thousands) |  |  | **2025** | **2024** |
| Cash, cash equivalents, and short-term investments |  |  | $107581 | $152114 |
| Total assets |  |  | $157059 | $206409 |
| Total liabilities |  |  | $58405 | $55767 |
| Accumulated deficit |  |  | $259669 | $201472 |
| Total stockholders' equity |  |  | $98654 | $150642 |
| Working capital (1) |  |  | $97074 | $146255 |
| &nbsp;&nbsp;&nbsp;&nbsp;__________ |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;(1) We define working capital as current assets less current liabilities. | &nbsp;&nbsp;&nbsp;&nbsp;(1) We define working capital as current assets less current liabilities. |  |  |  |

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