BBI-940 IND accepted; initiation of first-in-human clinical trial on track

for the first half of 2026

Portfolio prioritization, including discontinuation of POTENTIATE trial, extends operating runway into the second half of 2028

SAN DIEGO, Jan. 20, 2026 (GLOBE NEWSWIRE) -- Boundless Bio (NASDAQ:BOLD), a clinical-stage oncology company interrogating extrachromosomal DNA (ecDNA) biology to deliver transformative therapies to patients with previously intractable oncogene amplified cancers, today announced that the U.S. Food and Drug Administration (FDA) has accepted its Investigational New Drug (IND) application for its novel Kinesin oral degrader program, BBI-940. The Company also provided updates on the POTENTIATE clinical trial of BBI-355 and BBI-825 and its capital position.

BBI-940 novel Kinesin degrader program

The acceptance of the BBI-940 IND enables Boundless to advance the program into a first-in-human clinical trial for patients with metastatic breast cancer, KOMODO-1 (Kinesin Oral Molecular Degrader for Oncology-1), which is expected to initiate in the first half of 2026. Boundless's novel Kinesin oral degrader program targets a previously undrugged kinesin involved in DNA segregation, including ecDNA segregation, during mitosis. BBI-940 has demonstrated potent anti-tumor activity across a range of cancer cell lines as well as in mouse xenograft models, including single-agent tumor regressions. The Company expects to deliver initial proof-of-concept clinical data within its cash runway timeline.

"The acceptance of the BBI-940 IND marks an important milestone for our first-in-class Kinesin oral degrader program, enabling us to advance this differentiated anti-cancer approach into clinical development," said Zachary Hornby, President and Chief Executive Officer of Boundless Bio. "In parallel, our portfolio prioritization and disciplined capital allocation sharpen our focus on BBI-940, maximizing our potential to deliver high-impact therapies for patients with high unmet need cancers."

POTENTIATE clinical trial of BBI-355 and BBI-825

Following a strategic portfolio review, Boundless Bio has elected to cease enrollment of the Phase 1/2 POTENTIATE trial evaluating the combination of BBI-355, its oral, selective CHK1 inhibitor and BBI-825, its oral, selective RNR inhibitor, in oncogene-amplified cancers. This decision reflects market considerations, clinical data, and the Company's prioritization of programs with the greatest potential to deliver meaningful clinical impact and long-term value.

Financial Update

Based on the revised operating plan, the Company's streamlined operations will extend its operating runway into the second half of 2028, through the anticipated initial clinical proof of concept readout for BBI-940.

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 orally bioavailable, 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 Company's plans to initiate the KOMODO-1 trial of BBI-940 and the timing thereof; 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 commencement, 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 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, 2024, the Company's quarterly report on Form 10-Q for the quarterly period ended September 30, 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.

Contacts:

Investors

Renee Leck

renee@thrustsc.com

Media

Carly Scaduto

carly@thrustsc.com

Boundless Bio Advances Novel Kinesin Degrader Program BBI-940 and Extends Cash Runway