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Boundless Bio, Inc. (BOLD) - 10-Q Summary for Period Ended June 30, 2026

Business Context and Reporting Period

This is a Quarterly Report on Form 10-Q for Boundless Bio, Inc. for the period ended June 30, 2026. Boundless Bio is a clinical-stage oncology company focused on developing extrachromosomal DNA (ecDNA) directed therapeutic candidates (ecDTx). As of the filing date, the company is in the process of winding down its legacy operations following the announcement of a proposed merger with Serapha Bio, Inc. on June 22, 2026. The company is classified as an Emerging Growth Company and a Smaller Reporting Company.

Key Financial Metrics

Material Changes vs. Prior Period

• Merger Agreement: On June 22, 2026, the company entered into a merger agreement with Serapha Bio, Inc. Upon closing, Serapha stockholders are expected to own approximately 96.31% of the combined company, while Boundless Bio stockholders will own approximately 3.69%.
• Workforce Reduction: In connection with the merger, the company announced a reduction in workforce of approximately 75% on June 23, 2026, recognizing a charge of approximately $2.8 million in the quarter.
• Facility Termination: The company terminated its long-term headquarters lease effective May 31, 2026, incurring a $10.0 million cash termination payment and retaining a $0.5 million security deposit. This resulted in significant facility-related costs and asset impairments.
• Program Discontinuation: In June 2026, the company announced the discontinuation of its lead candidate, BBI-940, due to poor pharmacokinetic exposure data. Enrollment in the POTENTIATE trial (BBI-355) was ceased in January 2026, and the STARMAP trial (BBI-825) was wound down in 2025.
• Expense Increases: G&A expenses increased by $5.1 million year-over-year, driven by severance costs, stock-based compensation acceleration due to the merger, and legal fees related to the transaction. R&D expenses decreased slightly by $0.6 million, primarily due to the wind-down of clinical trials, partially offset by facility exit costs and asset impairments.

Guidance, Outlook, and Risks

• Merger Outlook: The transaction is expected to close in the fourth quarter of 2026, subject to stockholder approvals and other conditions. The combined company will focus on Serapha's SERP-01 program and will not continue development of Boundless Bio's legacy ecDTx.
• Pre-Closing Dividend: Boundless Bio expects to declare a special cash dividend of approximately $44 million to $48 million to existing stockholders prior to the closing of the merger to distribute excess net cash.
• Liquidity: As of June 30, 2026, the company held $72.6 million in cash and investments. Management believes this is sufficient to fund operations for at least 12 months, excluding the anticipated dividend and merger closing.
• Risks: Key risks include the failure to complete the merger, which could lead to liquidation or the need for significant additional capital. Other risks include the uncertainty of the pre-closing dividend amount, potential delisting from Nasdaq if conditions are not met, and the volatility of the stock price.

Key Facts for Investor Verification

• Merger Status: Verify the progress of stockholder approvals and the satisfaction of closing conditions for the Serapha Bio merger.
• Dividend Timing and Amount: Confirm the record date and final amount of the pre-closing cash dividend, which is estimated between $44 million and $48 million.
• Cash Runway: Monitor cash burn rates post-merger announcement to ensure sufficiency until the transaction closes or alternative financing is secured.
• Asset Disposition: Track the status of the wind-down of clinical trials and the potential monetization or transfer of legacy intellectual property if the merger does not proceed.
• Stock Ownership: Note the significant dilution of existing Boundless Bio shareholders, who are expected to retain only ~3.69% ownership in the combined entity.