Item 7.Management’s Discussion and Analysis of the Results of Operations

Statements in the following discussion and throughout this Form 10-K that are not historical in nature are “forward-looking statements.” You can identify forward-looking statements by the use of words such as “expect,” “anticipate,” “estimate,” “may,” “will,” “should,” “intend,” “believe,” and similar expressions. Although we believe the expectations reflected in these forward-looking statements are reasonable, such statements are inherently subject to risk and we can give no assurances that our expectations will prove to be correct. Actual results could differ from those described in this report because of numerous factors, many of which are beyond our control. These factors include, without limitation, those described under Item 1A “Risk Factors.” We undertake no obligation to update these forward-looking statements to reflect events or circumstances after the date of this report or to reflect actual outcomes. Please see “Special Cautionary Note Regarding Forward-Looking Statements” at the beginning of this Form 10-K.

The following discussion of our financial condition and results of operations should be read in conjunction with our financial statements and the related notes thereto and other financial information appearing elsewhere in this Form 10-K. We undertake no obligation to update any forward-looking statements in the discussion of our financial condition and results of operations to reflect events or circumstances after the date of this report or to reflect actual outcomes.

Overview

We are a clinical-stage biopharmaceutical company focused on translating today’s medical breakthroughs into potential cures for difficult-to-treat cancers. We aim to acquire rights to these technologies by licensing or otherwise acquiring an ownership interest in the technologies, funding their research and development and eventually either out-licensing or bringing the technologies to market.

Our pipeline is currently focused on novel therapies for solid tumors. For these therapies we have partnered with world class research institutions, including the City of Hope National Medical Center (“COH” or “City of Hope”), and Nationwide Children’s Hospital (“Nationwide”).

We expect to incur substantial expenses for the foreseeable future relating to research, development and commercialization of our potential products and may never achieve profitability. We do not have any products that are approved for commercial sale and, therefore, do not expect to generate any revenues from product sales in the foreseeable future, if ever. Additionally, there can be no assurance that we will be successful in securing additional resources when needed, on terms acceptable to us, if at all.

Development Pipeline

Our pipeline is being developed under exclusive licenses from world class research institutions. Our strategy is to license these technologies, support preclinical and clinical research activities by our partners and develop these product candidates through to potential approval.

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In partnership with COH, we are developing CAR T therapy for solid tumors targeting IL13Rα2 (MB-101). In addition, we have partnered with Nationwide for a herpes simplex virus type 1 (“HSV-1”) oncolytic virus (MB-108) in order to enhance the activity of MB-101 for the treatment of patients with high-grade malignant brain tumors. The Phase 1 clinical trial sponsored by COH for MB-101 (ClinicalTrials.gov Identifier: NCT02208362) has completed the treatment phase and patients continue to be assessed for long-term safety. A Phase 1 clinical trial sponsored by the University of Alabama at Birmingham (“UAB”) for MB-108 (ClinicalTrials.gov Identifier: NCT03657576) has also completed the treatment phase and patients continue to be assessed for long-term safety. In October 2023, we announced that the FDA accepted our IND application for the combination of MB-101 and MB-108 – which is referred to as MB-109 – for the treatment of patients with IL13Rα2+ relapsed or refractory glioblastoma (“GBM”) and high-grade astrocytoma. Pursuant to termination of the lease for our cell processing center in Worcester, MA, we are exploring with COH and Nationwide the possibility of initiating this clinical trial as an investigator-sponsored single-institution study at COH in the second quarter of 2026.

MB-109 (Combination of MB-101 CAR T Therapy with MB-108 Oncolytic Virus Therapy for Malignant Brain Tumors)

In October 2023, we received a safe-to-proceed letter from the FDA for our MB-109 IND application allowing us to initiate a Phase 1, open-label, non-randomized, multicenter study of MB-109 in patients with IL13Rα2+ recurrent GBM and high-grade astrocytoma. The Phase 1 clinical study under that IND would evaluate the combination of CAR-T cells (MB-101) and the herpes simplex virus type 1 oncolytic virus (MB-108) in patients with IL13Rα2+ high-grade gliomas. As originally written and approved by the FDA, the study involved first a lead-in cohort, wherein patients would be treated with MB-101 alone without prior MB-108 administration. This lead-in cohort was required by the FDA due to the change in cell processing site from COH to Mustang Bio, which would have involved methodological changes as well as the obvious change in equipment and personnel. After successful confirmation of the safety profile of MB-101 alone, the study would then investigate increasing doses of intratumorally administered MB-108 followed by dual intratumoral (ICT) and intraventricular (ICV) administration of MB-101.

On November 7, 2024, we announced that the FDA granted Orphan Drug Designation to Mustang for MB-108, an HSV-1 oncolytic virus, for the treatment of malignant glioma. On July 7, 2025, we announced that the FDA granted Orphan Drug Designation to Mustang for MB-101, IL13Ra2-targeted CAR T-cells, for the treatment of recurrent diffuse and anaplastic astrocytoma (astrocytomas) and glioblastoma. The Orphan Drug Designation provides certain incentives, such as tax credits toward the cost of clinical trials upon approval and prescription drug user fee waivers. If a product receives Orphan Drug Status from the FDA, that product is entitled to seven years of market exclusivity for the disease in which it has Orphan Drug designation, which is independent from intellectual property protection.

We are currently exploring with COH and Nationwide the possibility of conducting an investigator-sponsored single-institution trial under the COH IND to treat patients with IL13Rα2+ recurrent GBM and high-grade astrocytoma with MB-109 that could potentially be initiated in the second quarter of 2026. Because cell processing for MB-101 will revert back to COH – where the product continues to be manufactured today for other investigator-sponsored clinical trials being conducted by COH in malignant brain tumors (NCT04003649, NCT04661384, NCT04510051), we believe that it is reasonable to assume that the FDA will not require the aforementioned lead-in cohort. Should this, indeed, be the case, the first patient enrolled will receive the combination of MB-101 and MB-108, which will represent a considerable savings of time and money – as well as afford the potential benefit of both therapies to every patient treated on study.

Terminated Product Candidate (CAR-T Therapy)

In September 2025, we received notice from Fred Hutch of its intent to terminate the CD20 License for cause in connection with unpaid patent expenses and maintenance fees. A 90-day cure period was applicable under the CD20 License. In December 2025, we agreed to terminate the CD20 License with Fred Hutch in exchange for a mutual release of liability and forgiveness of approximately fifty percent of amounts previously owed to them. Additionally, we are eligible to receive royalties on any subsequent licensing consideration Fred Hutch may enter into during the three-year period following the termination.

To date, we have not received approval for the sale of any of our product candidates in any market and, therefore, have not generated any product sales from our product candidates. In addition, we have incurred substantial operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable.

Recent Events

Reverse Stock Split

On January 15, 2025, we filed a certificate of amendment (the “Amendment”) to our amended and restated certificate of incorporation, as amended, with the Secretary of State of the State of Delaware, to effect a 1-for-50 reverse stock split of our issued and outstanding common

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stock, without any change to par value. The Amendment became effective upon such filing. No fractional shares were issued in connection with the reverse stock split as all fractional shares were rounded down to the next whole share. The reverse stock split was intended to bring the Company into compliance with the continued listing requirements of The Nasdaq Stock Market LLC (“Nasdaq”).

All share and per share amounts of our common stock listed in this Form 10-K have been adjusted to give effect to the reverse stock split.

Termination of lease and sale of equipment

On February 10, 2025, we entered into a Bill of Sale and Surrender Agreement (the “Sale/Surrender Agreement”), effective as of January 31, 2025 (the “Effective Date”), with AbbVie Bioresearch Center Inc., a Delaware corporation (“AbbVie”). We were the tenant in the leased premises located at 377 Plantation Street, Worcester, Massachusetts (the “Premises”) under a Lease Agreement, dated as of October 27, 2017 (the “Lease”) with WCS - 377 Plantation Street, Inc., a Massachusetts nonprofit corporation (the “Landlord”). In connection with the entrance into the Sale/Surrender Agreement, we also entered into an Escrow Agreement, dated February 10, 2025 (the “Escrow Agreement”), with Bowditch & Dewey, LLP, as escrow agent (the “Escrow Agent”), pursuant to which the Escrow Agent would disburse the Purchase Price (defined herein) pursuant to the terms of the Escrow Agreement.

Pursuant to the terms of the Sale/Surrender Agreement, AbbVie agreed to purchase from us, and we agreed to sell and convey to AbbVie, certain furniture, fixtures and equipment (“FF&E”), which we classified as held for sale as of December 31, 2024, located in the Premises and other items as set forth in the Sale/Surrender Agreement for a purchase price of $1.0 million (the “Purchase Price”). AbbVie also agreed to lease the Premises from the Landlord following the termination of the Lease pursuant to a First Amendment to Lease Agreement (the “Amendment”), dated as of February 7, 2025.

The closing of the transactions described above occurred on February 21, 2025 (the “Closing”), with AbbVie’s issuance of an Acceptance Notice (as defined in the Sale/Surrender Agreement) to us stating that a Sufficient Percentage (as defined in the Sale/Surrender Agreement) of the FF&E items listed in the Sale/Surrender Agreement are present in the Premises and functional for their intended purpose without the need for repair or replacement. On February 25, 2025, as a result of the issuance of the Acceptance Notice, pursuant to the terms of the Escrow Agreement, the Escrow Agent released the Purchase Price to us. On February 27, 2025, we announced the relocation of our corporate headquarters to 95 Sawyer Road, Waltham, Massachusetts 02453.

Financing Activities

February 2025 Equity Offering (the “February 2025 Equity Offering”)

On February 5, 2025, we commenced a best efforts public offering of an aggregate of (i) 495,000 shares (the “Shares”) of its common stock, par value $0.0001 per share, (ii) pre-funded warrants (the “Pre-Funded Warrants”) to purchase up to an aggregate of 2,162,807 shares of common stock (the “Pre-Funded Warrant Shares”), (iii) Series C-1 warrants (the “Series C-1 Warrants”) to purchase up to an aggregate of 2,657,807 shares of common stock (the “Series C-1 Warrant Shares”), and (iv) Series C-2 warrants (the “Series C-2 Warrants,” and together with the Series C-1 Warrants, the “Warrants”) to purchase up to an aggregate of 2,657,807 shares of common stock (the “Series C-2 Warrant Shares,” and together with the Series C-1 Warrant Shares, the “Warrant Shares”). Each Share or Pre-Funded Warrant was sold together with one Series C-1 Warrant to purchase one share of common stock and one Series C-2 Warrant to purchase one share of common stock. The combined public offering price for each Share and accompanying Warrants was $3.01, and the combined public offering price for each Pre-Funded Warrant and accompanying Warrants was $3.0099.

The Pre-Funded Warrants have an exercise price of $0.0001 per share, are exercisable immediately upon issuance and will expire when exercised in full. Each Warrant has an exercise price of $3.01 per share and will be exercisable beginning on the effective date of stockholder approval of the issuance of the Warrant Shares (the “Warrant Stockholder Approval”). The Series C-1 warrants will expire five years from the Warrant Stockholder Approval and the Series C-2 warrants will expire twenty-four months from the Warrant Stockholder Approval.

The net proceeds of the Offering, after deducting the fees and expenses of the Placement Agent (as defined below), described in more detail below, and other offering expenses payable by the Company, but excluding the net proceeds, if any, from the exercise of the Warrants, was approximately $6.8 million. The February 2025 Equity Offering closed on February 10, 2025.

July 2025 Warrant Exercises

In July 2025, certain investors from the February 2025 Equity Offering exercised outstanding Pre-Funded and Series C-2 warrants resulting in us issuing approximately 2.9 million shares of our common stock and our receipt of proceeds of approximately $7.1 million.

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At the Market Offering Agreement

On May 31, 2024, we entered into an At the Market Offering Agreement (the “ATM Agreement”) with Wainwright (the “Manager”) under which we may offer and sell, from time to time at our sole discretion, shares of our common stock (the “ATM Shares”), through or to the Manager. The offer and sale, if any, of ATM Shares by us under the Offering Agreement will be made pursuant to our registration statement on Form S-3 (File No. 333-279891) (the “Registration Statement”) under the Securities Act, and the related prospectus included therein, filed with the SEC on May 31, 2024, and declared effective on June 12, 2024.

Under the ATM Agreement, the Manager may sell ATM Shares by any method permitted by law deemed to be an “at the market offering” as defined in Rule 415(a)(4) under the Securities Act. The Manager will use commercially reasonable efforts to sell the ATM Shares from time to time, based upon instructions from us (including any price, time or size limits or other customary parameters or conditions we may impose). We will pay the Manager a commission of 3.0% of the gross proceeds from the sales of ATM Shares sold through the Manager under the ATM Agreement and have provided the Manager with customary indemnification and contribution rights. We will also reimburse the Manager for certain expenses incurred in connection with the ATM Agreement. Together with the Manager, we may each terminate the ATM Agreement at any time upon specified prior written notice.

The offering of ATM Shares pursuant to the ATM Agreement will terminate upon the earlier of (i) the sale of all ATM Shares subject to the ATM Agreement or (ii) the termination of the ATM Agreement in accordance with its terms.

During the year ended December 31, 2025, we issued approximately 54,000 shares of common stock at an average price of $11.55 for gross proceeds of $0.6 million under the ATM Agreement. In connection with these sales, we paid aggregate fees of approximately $27,000.

The number of securities we are able to sell pursuant to the registration statements on Form S-3 is limited. See “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations – Liquidity and Capital Resources.”

Critical Accounting Policies and Use of Estimates

Our financial statements include certain amounts that are based on management’s best estimates and judgments. Our significant estimates include, but are not limited to, useful lives assigned to long-lived assets and amortizable intangible assets, fair value of stock options and warrants, stock-based compensation, accrued expenses, provisions for income taxes and contingencies. Due to the uncertainty inherent in such estimates, actual results may differ from these estimates. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources.

Actual results may differ from these estimates under different assumptions or conditions. We believe that the accounting policies discussed below are critical to understanding our historical and future performance, as these policies relate to the more significant areas involving management’s judgments and estimates.

While our significant accounting policies are described in the notes to our financial statements included elsewhere in this Annual Report on Form 10-K, we believe that the following critical accounting policies are most important to understanding and evaluating our reported financial results.

Research and Development

Research and development costs are expensed as incurred. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. Upfront and milestone payments due to third parties that perform research and development services on our behalf will be expensed as services are rendered or when the milestone is achieved.

Research and development costs primarily consist of personnel related expenses, including salaries, benefits, travel, and other related expenses, stock-based compensation, payments made to third parties for license and milestone costs related to in-licensed products and technology, payments made to third party contract research organizations for preclinical and clinical studies, investigative sites for clinical trials, consultants, the cost of acquiring and manufacturing clinical trial materials, and costs associated with regulatory filings, laboratory costs and other supplies.

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In accordance with ASC 730 10 25 1, Research and Development, costs incurred in obtaining technology licenses are charged to research and development expense if the technology licensed has not reached commercial feasibility and has no alternative future use. In each case, we evaluate if the license agreement results in the acquisition of an asset or a business. Such licenses purchased by us require substantial completion of research and development, regulatory and marketing approval efforts in order to reach commercial feasibility and have no alternative future use. Accordingly, the total purchase price for the licenses acquired during the period was reflected as research and development expenses on the Statements of Operations for the years ended December 31, 2025, and 2024.

Accrued Research and Development Expense

We record accruals for estimated costs of research, preclinical, clinical and manufacturing development within accrued expenses which are significant components of research and development expenses. A substantial portion of our ongoing research and development activities is conducted by third-party service providers. We accrue the costs incurred under agreements with these third parties based on estimates of actual work completed in accordance with the respective agreements. We determine the estimated costs through discussions with internal personnel and external service providers as to the progress, or stage of completion or actual timeline (start-date and end-date) of the services and the agreed-upon fees to be paid for such services. Payments made to third parties under these arrangements in advance of the performance of the related services are recorded as prepaid expenses until the services are rendered.

If the actual timing of the performance of services or the level of effort varies from the estimate, we adjust accrued expenses or prepaid expenses accordingly, which impact research and development expenses. Although we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period.

Recent Accounting Pronouncements

See Note 2 to the financial statements included in this Form 10-K.

Smaller Reporting Company Status

We are a “smaller reporting company,” meaning that the market value of our shares held by non-affiliates is less than $700 million and our annual revenue was less than $100 million during the most recently completed fiscal year. We may continue to be a smaller reporting company if either (i) the market value of our shares held by non-affiliates is less than $250 million or (ii) our annual revenue was less than $100 million during the most recently completed fiscal year and the market value of our shares held by non-affiliates is less than $700 million. As a smaller reporting company, we may choose to present only the two most recent fiscal years of audited financial statements in our Annual Report on Form 10-K , have reduced disclosure obligations regarding executive compensation, and smaller reporting companies are permitted to delay adoption of certain recent accounting pronouncements discussed in Note 2 to our financial statements located in “Part IV, Item 15., Exhibits and Financial Statement Schedules” in this Form 10-K.

Results of Operations

Comparison of the Years Ended December 31, 2025 and 2024

For the year ended December 31, Change

Operating expenses:

Other income

Other income — 314 (314) (100) %

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Research and Development Expenses

Research and development expenses primarily consist of personnel related expenses, including salaries, benefits, travel, and other related expenses, stock-based compensation, payments made to third parties for license, sponsored research and milestone costs related to in-licensed products and technology, payments made to third party contract research organizations for preclinical and clinical studies, investigative sites for clinical trials, consultants, the cost of manufacturing clinical trial materials, costs associated with regulatory filings and laboratory service costs.

Research and development expenses decreased by approximately $9.9 million from $8.4 million for the year ended December 31, 2024, to ($1.5) million for the year ended December 31, 2025. The decrease in research and development expense for the year ended December 31, 2025, was primarily attributable to the following:

● $1.0 million decrease in clinical trial related costs;

● $2.0 million decrease in sponsored research and license related expenses;

● $0.5 million decrease in consulting expenses;

● $0.6 million decrease in depreciation expense;

● $1.0 million decrease in other expenses; offset by

Additionally, we have been actively negotiating settlements of aged payables, and recognized savings of approximately $2.1 million, which resulted in a credit for research and development expenses during the year ended December 31, 2025. This credit is not indicative of our research and development expenses going forward.

Asset Impairment

For the year ended December 31, 2024, we incurred impairment charges of $3.7 million, of which approximately $2.7 million was attributable to our assessment of the recoverability of the asset group consisting of leasehold improvements and associated right-of-use asset, and approximately $1.0 million was attributable to property, plant and equipment held for sale at December 31, 2024, and subsequently sold in 2025. No impairment was recorded in the year ended December 31, 2025.

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and related expenses, including stock-based compensation, for executives and other administrative personnel, recruitment expenses, professional fees and other corporate expenses, including investor relations, legal activities including patent fees, and facilities-related expenses.

General and administrative expense decreased by approximately $0.2 million from $4.1 million for the year ended December 31, 2024, to $3.9 million for the year ended December 31, 2025. The decrease in general and administrative expense for the year ended December 31, 2025, was primarily attributable to the following:

● $0.5 million decrease in consulting expenses;

● $0.1 million decrease in legal and patent protection expenses; offset by

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Total Other Income

Other income for the year ended December 31, 2025, was $0.5 million relating to interest income. Other income for the year ended December 31, 2024, was $0.5 million relating to the non-repeat gain on the termination of the Mercantile Center lease in June 2024 and $0.2 million of interest income.

Liquidity and Capital Resources

Since our inception, we have incurred substantial operating losses and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. To date, we have funded our operations primarily with the proceeds from sales of equity securities. As of December 31, 2025, we had an accumulated deficit of $398.6 million and cash and cash equivalents of $17.3 million.

We have previously disclosed in our financial statements for the year ended December 31, 2024, and our most recent quarterly report on Form 10-Q for the period ended September 30, 2025, that substantial doubt existed regarding our ability to continue as a going concern. Although we have a history of negative cash flows from operations and operating losses, we have raised approximately $14.5 million in net proceeds from the February 2025 Equity Offering, the ATM Agreement and the July 2025 warrant exercises, as described in “Financing Activities” above, during the year ended December 31, 2025. In addition to these net proceeds, we have been actively negotiating settlements of aged payables and have recognized approximately $2.1 million in savings during the year ended December 31, 2025, and we have significantly reduced our operating costs.

We expect to continue generating operating losses and negative operating cash flows as we develop our products through to potential approval, however, based on the improvement in our cash position for the year ended December 31, 2025, we believe we have sufficient cash and cash equivalents to fund our operations for at least twelve months from the date of this annual report on Form 10-K. Therefore, we have concluded that substantial doubt no longer exists.

As of the date of this Form 10-K, our public float was less than $75 million. As a result, we are subject to the limitations of General Instruction I.B.6 to Form S-3 until such time as our public float exceeds $75 million, which means we only have the capacity to sell an amount of securities up to one-third of our public float under shelf registration statements in any twelve-month period. If our public float decreases, the number of securities we may sell under our Form S-3 shelf registration statements will also decrease. We will remain constrained by the limitations of General Instruction I.B.6 to Form S-3 until such time as our public float exceeds $75 million, at which time the number of securities we may sell under a Form S-3 registration statement will no longer be limited by limitations of General Instruction I.B.6 to Form S-3.

Sources of Liquidity

Registration Statements

On May 31, 2024, the Company filed a shelf registration statement on Form S-3 (File No. 333-279891) (the “2024 S-3”), which was declared effective on June 12, 2024. Under the 2024 S-3, the Company may sell up to a total of $40.0 million of its securities. As of December 31, 2025, approximately $34.2 million of the 2024 S-3 remained available for sales of securities.

As of the filing of this Form 10-K, the Company is subject to the General Instruction I.B.6 to Form S-3, known as the “baby shelf rules,” which limit the number of securities it can sell under its registration statements on Form S-3.

Equity Offerings

During the year ended December 31, 2025, we completed the February 2025 Equity Offering and the July 2025 Warrant Exercises (together, the “Capital Raises”),as described above in “Management’s Discussion and Analysis of the Results of Operations – Financing Activities.” Net proceeds from the Capital Raises were approximately $14.3 million. We intend to use the net proceeds from the Capital Raises for working capital and general corporate purposes.

In connection with the February 2025 Equity Offering and July 2025 Warrant Exercises, pursuant to the Founders Agreement, we issued 125,779 shares of common stock to Fortress.

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At-the-Market Offering

On May 31, 2024, the Company entered into an At-the-Market Offering Agreement (the “Offering Agreement”) with Wainwright (the “Manager”) under which the Company may offer and sell, from time to time at its sole discretion, shares of its common stock through or to the Manager pursuant to the 2024 S-3. Under the Offering Agreement, the Company pays the Manager a commission of 3.0% of the gross proceeds from the sales of any shares of common stock. The Company will also reimburse the Manager for certain expenses incurred in connection with the Offering Agreement. The Company and the Manager may each terminate the Sales Agreement at any time upon specified prior written notice.

During the year ended December 31, 2025, the Company issued approximately 54,000 shares of common stock at an average price of $11.55 per share for gross proceeds of $0.6 million under the ATM Agreement. In connection with these sales, the Company paid aggregate fees of approximately $27,000 for net proceeds of approximately $0.6 million.

During the year ended December 31, 2024, the Company issued approximately 140,000 shares of common stock at an average price of $18.78 per share for gross proceeds of $2.6 million under the ATM Agreement. In connection with these sales, the Company paid aggregate fees of approximately $0.1 million for net proceeds of approximately $2.5 million.

Pursuant to the Founders Agreement, the Company issued 1,361 shares of common stock to Fortress at a weighted average price of $11.55 per share for the year ended December 31, 2025. For the year ended December 31, 2024, the Company issued 3,509 shares of common stock to Fortress at a weighted average price of $18.78 per share.

Cash Flows

The following table summarizes our cash flows during the years ended December 31, 2025 and 2024:

For the year ended December 31,

Statement of cash flows data:

Total cash (used in) provided by:

Investing activities 1,165 —

Net change in cash and cash equivalents $ 10,427 $ (145)

Operating Activities

Net cash used in operating activities for the year ended December 31, 2025, was primarily due to approximately $1.9 million in net loss, $1.7 million change in operating assets and liabilities, $2.1 million non-cash savings from the settlement of payables, $0.4 million gain on the termination of the Plantation Street Facility lease, partially offset by $0.4 million equity fee to Fortress, $0.3 million common shares issuable in connection with Annual Stock Dividend to Fortress and $0.1 million non-cash stock based compensation.

Net cash used in operating activities for the year ended December 31, 2024, was primarily due to approximately $15.8 million in net loss, $2.4 million non-cash savings from the settlement of payables, $0.5 million of non-cash stock based compensation, and $0.3 million gain on the termination of lease, partially offset by $3.7 million of asset impairment, $1.8 million change in operating assets and liabilities, $0.7 million of depreciation expense, $0.6 million of common shares issuable in connection with the Annual Stock Dividend to Fortress, $0.3 million equity fee to Fortress related to Mustang ATM and Equity Offerings, $0.2 million of amortization of operating lease right-of-use assets, and $0.3 million in research and development – licenses acquired.

Investing Activities

Net cash provided by investing activities was $1.2 million for the year ended December 31, 2025, which primarily reflects the proceeds from the sale of equipment to AbbVie.

No cash was used in or provided by investing activities for the year ended December 31, 2024.

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Financing Activities

Net cash provided by financing activities was $14.5 million during the year ended December 31, 2025, primarily reflecting the proceeds from the February 2025 Equity Offering, the ATM Agreement and the July 2025 warrant exercises.

Net cash provided by financing activities was $11.3 million during the year ended December 31, 2024, primarily reflecting the proceeds from the May 2024 Offering, June 2024 Offering and the ATM Agreement.

Contractual Obligations

We enter into contracts in the normal course of business with licensors, CROs, contract manufacturing organizations (“CMOs”) and other third parties for the procurement of various products and services, including without limitation biopharmaceutical development, biologic assay development, commercialization, clinical and preclinical development, clinical trials management, pharmacovigilance and manufacturing and supply. These contracts typically do not contain minimum purchase commitments (although they may) and are generally terminable by us upon written notice. Payments due upon termination or cancelation/delay consist of payments for services provided or expenses incurred, including non-cancelable obligations of our service providers, up to the date of cancellation; in certain cases, our contractual arrangements with CROs and CMOs include cancelation and/or delay fees and penalties.

Item 7A.Quantitative and Qualitative Disclosures About Market Risks

None.

Item 8.Financial Statements and Supplementary Data.

The information required by this Item is set forth in the financial statements and notes thereto beginning at page F-1 of this Form 10-K.

Item 9.Changes in and Disagreements with Accountants on Accounting and Financial Disclosure.

None.

Item 9A.Controls and Procedures.

Disclosure Controls and Procedures

Controls and Procedures

Disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) are designed only to provide reasonable assurance that they will meet their objectives. Under the supervision and with the participation of our management, including our principal executive and financial officer, we conducted an evaluation of the effectiveness, as of December 31, 2025, of the design and operation of our disclosure controls and procedures, as such term is defined in Exchange Act Rules 13a-15(e) and 15d-15(e). Based on this evaluation, our principal executive and financial officer concluded that, as of such date, our disclosure controls and procedures were effective to ensure that information required to be disclosed by us in our Exchange Act reports is recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms, and that such information is accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate to allow timely decisions regarding required disclosure.

Internal Control over Financial Reporting

Management’s Report on Internal Control over Financial Reporting.

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Exchange Act Rules 13a-15(f) and 15d-15(f). Internal control over financial reporting refers to the process designed by, or under the supervision of, our principal executive and financial officer, and effected by our Board, management and other personnel, to provide

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reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles, and includes those policies and procedures that:

Internal control over financial reporting has inherent limitations. Internal control over financial reporting is a process that involves human diligence and compliance and is subject to lapses in judgment and breakdowns resulting from human failures. Internal control over financial reporting also can be circumvented by collusion or improper management override. Because of such limitations, there is a risk that material misstatements may not be prevented or detected on a timely basis by internal control over financial reporting. However, these inherent limitations are known features of the financial reporting process. Therefore, it is possible to design into the process safeguards to reduce, though not eliminate, this risk.

Our management assessed the effectiveness of our internal control over financial reporting as of December 31, 2025. In making the assessment, management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (“COSO”) in Internal Control - Integrated Framework (2013).

Based on our assessment, our management has concluded that, as of December 31, 2025, our internal controls over financial reporting were effective based upon those criteria.

Changes in Internal Controls over Financial Reporting.

There were no changes in our internal control over financial reporting during our most recent fiscal quarter that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Item 9B.Other Information

During the three months ended December 31, 2025, none of our directorsorofficersadopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K.

Item 9C. Disclosure Regarding Foreign Jurisdiction that Prevents Inspections.

None.

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PART III

Item 10.Directors, Executive Officers and Corporate Governance

The following table sets forth information regarding our executive officers and directors, including their ages as of the date of this Form 10-K.

Name Age Position(s)

Executive Officers

Non-Employee Directors

Michael S. Weiss 60 Chairman of the Board of Directors and Executive Chairman

Adam J. Chill 58 Director

Neil Herskowitz 69 Director

David Jin 35 Director

Lindsay A. Rosenwald, M.D. 70 Director

Michael J. Zelefsky, M.D. 65 Director

Information about our Executive Officers

Manuel Litchman, M.D. - President, Chief Executive Officer, Interim Chief Financial Officer and Director

Dr. Litchman has served as our President and Chief Executive Officer, and as a member of our Board since April 2017 and as Interim Chief Financial Officer since November 2024. Dr. Litchman has also served on the board of Cascade Prodrug, LLC, a private biotechnology company, since August 2025. Dr. Litchman joined us from Arvinas, LLC, where he served as President and Chief Executive Officer. While at Arvinas, Dr. Litchman oversaw the advancement of the company’s pipeline of protein-degradation therapeutics for the treatment of cancers and other diseases toward Investigational New Drug applications and secured multi-target discovery collaborations with Merck and Genentech. Prior to Arvinas, Dr. Litchman spent more than 18 years with Novartis Pharmaceuticals Corporation, where he held positions of increasing responsibility related to the development of Novartis’ oncology pipeline. Most recently, Dr. Litchman served as Senior Vice President and Executive Global Program Head, CTL019, Cell & Gene Therapies Unit, where he led a collaboration with the University of Pennsylvania investigating chimeric antigen receptor modified T cells (“CAR Ts”) directed against CD19 on B cell malignancies. Prior to the CTL019 collaboration, Dr. Litchman served as Novartis’ Vice President and Head, Oncology Business Development & Licensing. Earlier in his career, Dr. Litchman was a senior equity analyst at Ursus Capital and directed oncology/immunology clinical research at Hoffmann-La Roche Inc. Dr. Litchman received his M.D. from Yale University School of Medicine, and his B.A. from Princeton University. He completed his internal medicine residency and hematology-oncology fellowship at New York-Presbyterian/Weill Cornell Medical Center. Based on Dr. Litchman’s biotechnology and pharmaceutical industry experience and in-depth understanding of our business, we believe that Dr. Litchman has the appropriate set of skills to serve as a member of the Board.

Information about our Non-Employee Directors

Michael S. Weiss – Chairman of the Board of Directors and Executive Chairman

Mr. Weiss has served as Chairman of our Board since May 2015 and has also served as our Executive Chairman since January 2017. He previously served as our interim President & Chief Executive Officer from March 2015 to April 2017. He is also a board member and the Executive Vice Chairman, Strategic Development of Fortress Biotech, Inc., a position he has held since February 2014. Since December 2011, Mr. Weiss has served in multiple capacities at TG Therapeutics, Inc., and is currently its Chairman, President and Chief Executive Officer. Mr. Weiss earned his J.D. from Columbia Law School and his B.S. in Finance from The University at Albany. He began his professional career as a lawyer with Cravath, Swaine & Moore LLP. From 2002 to 2009, Mr. Weiss was the Chairman and Chief Executive Officer of Keryx Biopharmaceuticals, Inc. Additionally, Mr. Weiss co-founded and served as Co-Portfolio Manager and Managing Partner of Opus Point Partners, LLC from 2009 to 2019. Based on Mr. Weiss’s biotechnology and pharmaceutical industry experience, as well as his extensive management experience, we believe that Mr. Weiss has the appropriate set of skills to serve as a member of the Board.

Effective January 1, 2017, our Board approved and authorized the execution of a Board Advisory Agreement with Caribe BioAdvisors, LLC (the “Advisor”), which is owned by Michael S. Weiss, to provide the Board with the advisory services of Mr. Weiss as Chairman of the

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Board and Executive Chairman. Pursuant to the Advisory Agreement, the Advisor is paid an annual cash fee of $60,000, in addition to any and all annual equity incentive grants paid to members of the Board.

Adam J. Chill – Director

Mr. Chill has served as a member of our Board since June 2017. Mr. Chill is the President of and a Portfolio Manager at Kingsbrook Partners LP, an alternative asset management firm he co-founded in March 2009. From February 2001 to March 2009, Mr. Chill was a Portfolio Manager and Managing Director at Highbridge Capital Management, LLC, an alternative asset management firm owned by J.P. Morgan Asset Management. At Highbridge, Mr. Chill was responsible for structuring, negotiating and monitoring Highbridge’s portfolio of structured investments in public and private companies worldwide. From April 2000 to February 2001, Mr. Chill worked at Angelo, Gordon & Co., an alternative asset management firm. From October 1992 to April 2000, Mr. Chill was a corporate attorney specializing in securities and mergers and acquisitions at Stroock & Stroock & Lavan LLP. Mr. Chill is a co-founder of the Bayit Association of New Jersey. Mr. Chill received his B.A., magna cum laude, from Yeshiva University and his J.D. from Columbia University School of Law, where he was a Harlan Fiske Stone Scholar. Based on Mr. Chill’s extensive investment experience and knowledge of the biotechnology industry, we believe that Mr. Chill has the appropriate set of skills to serve as a member of the Board.

Neil Herskowitz – Director

Mr. Herskowitz has served as a member of our Board since August 2015. Mr. Herskowitz has served as the managing member of the ReGen Group of companies, located in New York, since 1998, which include ReGen Capital Investments LLC and Riverside Claims Investments LLC. He has also served as the President of its affiliate, Riverside Claims LLC, since June 2004. Mr. Herskowitz serves as a member of the board of directors for our affiliate, Avenue Therapeutics, Inc. Mr. Herskowitz received a B.B.A. in Finance from Bernard M. Baruch College in 1978. Based on Mr. Herskowitz’s financial industry experience and in-depth understanding of our business, we believe that Mr. Herskowitz has the appropriate set of skills to serve as a member of the Board.

David Jin – Director

Mr. Jin has served as a member of our Board since October 2024. Mr. Jin has served as the Chief Financial Officer of Fortress since August 2022 and Head of Corporate Development since May 2020. He also serves as Chief Operating Officer, Interim Chief Financial Officer and Corporate Secretary of Avenue Therapeutics, Inc. (a Fortress partner company) and as a member of the board of directors of Crystalys Therapeutics. Since August 2022, Mr. Jin has served as Treasurer of Fortress’ private subsidiaries, including Cyprium Therapeutics, Urica Therapeutics, Helocyte, and Cellvation. From March 2022 to August 2022, he served as Interim Chief Executive Officer at Avenue Therapeutics. Previously, he was on the investment team in the Private Equity & Real Assets group at Barings, Director of Corporate Development at Sorrento Therapeutics, Vice President of Healthcare Investment Banking at FBR & Co., and was in the management consulting group at IMS Health (now IQVIA). He holds a B.S. in Industrial Engineering & Management Sciences with a double-major in Mathematical Methods in the Social Sciences from Northwestern University. Based on Mr. Jin’s financial experience and knowledge of the biotechnology industry, we believe that Mr. Jin has the appropriate set of skills to serve as a member of the Board.

Lindsay A. Rosenwald, M.D. – Director

Dr. Rosenwald has served as a member of our Board since our inception. Dr. Rosenwald has been a member of the Board of Directors of Fortress Biotech, Inc. since October 2009 and has served as its Chairman, President and Chief Executive Officer since December 2013. He also serves on the board of directors of Avenue Therapeutics, Inc. and Journey Medical Corporation. Prior to that, from 1991 to 2008, he served as the Chairman of Paramount BioCapital, Inc. Over the last 30 years, Dr. Rosenwald has acted as a biotechnology entrepreneur and has been involved in the founding and recapitalization of numerous public and private biotechnology and life sciences companies. Dr. Rosenwald received his B.S. in finance from Pennsylvania State University and his M.D. from Temple University School of Medicine. We believe that Dr. Rosenwald’s extensive biotechnology, pharmaceutical and finance expertise, as well as his medical background and in-depth understanding of our businesses, makes him an exemplary candidate to continue serving on our Board.

Michael J. Zelefsky, M.D. – Director

Dr. Zelefsky has served as a member of our Board since June 2017. Dr. Zelefsky has served as a Member at NYU Langone since 2023 and before that was a Member at the Memorial Sloan-Kettering Cancer Center Department of Radiation Oncology since 2005. He has served as Chief of Memorial Sloan-Kettering’s Brachytherapy Services since 2000 and has been a Professor of Radiation Oncology at Weill Cornell Medical College, Cornell University since 1994. He is a recognized expert in radiation therapy and has helped develop and enhance Memorial Sloan-Kettering’s prostate brachytherapy program during his tenure. Dr. Zelefsky received a Bachelor of Arts in Biology (summa cum laude) from Yeshiva University in 1982 and a Medical Doctor degree from Albert Einstein College of Medicine in 1986. Dr. Zelefsky is currently

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Editor-in-Chief of Brachytherapy and has previously served as president of the American Brachytherapy Society. Based on Dr. Zelefsky’s extensive experience and background in oncology, we believe that Dr. Zelefsky has the appropriate set of skills to serve as a member of the Board.

Family Relationships

There is no family relationship between and among any of our executive officers or directors.

Board Structure and Leadership

Our Bylaws provide that our Board shall consist of between one and nine directors, and such number of directors within this range may be determined from time to time by resolution of our board of directors or our stockholders. Currently, we have seven directors.

The Board does not have a formal policy regarding the separation of the roles of Chief Executive Officer and Chairman of the Board, as the Board believes that it is in the best interests of the Company to make that determination based on the direction of the Company and the current membership of the Board. The Board has determined that having a director who is also the Chief Executive Officer serve as the Chairman is not in the best interest of the Company’s stockholders at this time.

During 2025, our Board held six meetings. During 2025, each director attended at least 75% of the meetings of the Board and the meetings of those committees on which each director served, in each case during the period that such person was a director. The permanent committees established by our Board are the Audit Committee and the Compensation Committee, descriptions of which are set forth in more detail below. Our directors are expected to attend each Annual Meeting of Stockholders.

Director Independence

We adhere to the corporate governance standards adopted by Nasdaq. Nasdaq rules require our Board to make an affirmative determination as to the independence of each director. Consistent with these rules, our Board completed its annual review of director independence and considered relationships and transactions during 2025 between each director or any member of his immediate family, on the one hand, and the Company and our subsidiaries and affiliates, on the other hand. The purpose of this review was to determine whether any such relationships or transactions were inconsistent with a determination that the director is independent. Based on this review, our Board determined that Adam Chill, Neil Herskowitz, and Michael Zelefsky, M.D., are independent under the criteria established by Nasdaq and our Board.

Fortress Biotech, Inc. (“Fortress”) beneficially owns capital stock representing more than 50% of the voting power of our outstanding voting stock eligible to vote in the election of directors. As a result, we qualify as a “controlled company” and avail ourselves of certain “controlled company” exemptions under the Nasdaq corporate governance rules. As a controlled company, we are not required to have a majority of “independent directors” on our Board as defined under the Nasdaq rules, or have a compensation, nominating or governance committee composed entirely of independent directors. Despite qualifying as a controlled company, we have a separately constituted Compensation Committee consisting entirely of independent directors.

Board Committees

The permanent committees established by our Board are the Audit Committee and the Compensation Committee, descriptions of which are set forth in more detail below.

Audit Committee

The Audit Committee currently consists of Adam J. Chill, Neil Herskowitz, and Michael J. Zelefsky, M.D. Mr. Chill chairs the Audit Committee.

The Audit Committee held four meetings during the fiscal year ended December 31, 2025. The duties and responsibilities of the Audit Committee are set forth in the Charter of the Audit Committee which was recently reviewed by our Audit Committee. A copy of the Charter of the Audit Committee is available on our website, located at ir.mustangbio.com. Among other things, the duties and responsibilities of the Audit Committee include reviewing and monitoring our financial statements and internal accounting procedures, the selection of, consultation with and review of the services provided by our independent registered public accounting and identifying and assessing any related party transactions in collaboration with counsel, accountants and management. Our Audit Committee has sole discretion over the retention, compensation, evaluation and oversight of our independent registered public accounting firm.

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The SEC and Nasdaq have established rules and regulations regarding the composition of audit committees and the qualifications of audit committee members. Our Board has examined the composition of our Audit Committee and the qualifications of our Audit Committee members in light of the current rules and regulations governing audit committees. Based upon this examination, our Board has determined that each member of our Audit Committee is independent and is otherwise qualified to be a member of our Audit Committee in accordance with the rules of the SEC and Nasdaq.

Additionally, the SEC requires that at least one member of the Audit Committee have a “heightened” level of financial and accounting sophistication. Such a person is known as the “audit committee financial expert” under the SEC’s rules. Our Board has determined that Mr. Chill is an “audit committee financial expert,” as the SEC defines that term, and is an independent member of our Board and our Audit Committee. Please see Mr. Chill’s biography in Item 10. Directors, Executive Officers, and Corporate Governance.

Compensation Committee

The Compensation Committee currently consists of Adam J. Chill, Neil Herskowitz and Michael J. Zelefsky, M.D. Mr. Herskowitz chairs the Compensation Committee.

The Compensation Committee held one meeting during the fiscal year ended December 31, 2025. The duties and responsibilities of the Compensation Committee are set forth in the Charter of the Compensation Committee which was recently reviewed by our Compensation Committee. A copy of the Charter of the Compensation Committee is available on our website, located at ir.mustangbio.com. As discussed in its Charter, among other things, the duties and responsibilities of the Compensation Committee include approving any corporate goals and objectives relating to the compensation of our executive officers, evaluating the performance of our executive officers, and administering all of our executive compensation programs, including, but not limited to, our incentive and equity-based plans. The Compensation Committee evaluates the performance of all of our executive officers on an annual basis and reviews and approves on an annual basis all compensation programs and awards relating to such officers. The Compensation Committee applies discretion in the determination of individual executive compensation packages to ensure compliance with our compensation philosophy. Our Chief Executive Officer makes recommendations to the Compensation Committee with respect to the compensation packages for officers other than himself.

Nasdaq has established rules and regulations regarding the composition of compensation committees and the qualifications of compensation committee members. Our Board has examined the composition of our Compensation Committee and the qualifications of our Compensation Committee members in light of the current rules and regulations governing compensation committees. Based upon this examination, our Board of Directors has determined that each member of our Compensation Committee is independent and is otherwise qualified to be a member of our Compensation Committee in accordance with such rules.

Nominating Process

We do not currently have a nominating committee or any other committee serving a similar function. Although we do not have a written charter in place to select director nominees, our Board has adopted resolutions regarding the director nomination process. We believe that the current process in place functions effectively to select director nominees who will be valuable members of our Board.

We identify potential nominees to serve as directors through a variety of business contacts, including current executive officers, directors, community leaders and stockholders. We may, to the extent deemed appropriate by the Board, retain a professional search firm and other advisors to identify potential nominees.

We will also consider candidates recommended by stockholders for nomination to our Board. A stockholder who wishes to recommend a candidate for nomination to our Board must submit such recommendation to our Corporate Secretary, at our offices located at 95 Sawyer Road, Suite 110, Waltham, MA 02453. Any recommendation must be received not less than 50 calendar days nor more than 90 calendar days before the anniversary date of the previous year’s annual meeting.

On April 7, 2017, we entered into an Executive Employment Agreement with Dr. Litchman, pursuant to which, among other things, we agreed to use our best efforts to cause Dr. Litchman to be nominated and reelected to the Board. Except as described herein, there are no arrangements or understandings between any of our executive officers or directors and any other person pursuant to which any of them are elected as an officer or director.

We believe that our Board as a whole should encompass a range of talent, skill, and expertise enabling it to provide sound guidance with respect to our operations and interests. Our independent directors evaluate all candidates to our Board by reviewing their biographical information and qualifications. If the directors determine that a candidate is qualified to serve on our Board, such candidate is interviewed by at least one of the directors and our Chief Executive Officer. Other members of the Board also have an opportunity to interview qualified candidates. The directors then determine, based on the background information and the information obtained in the interviews, whether to

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recommend to the Board that the candidate be nominated for approval by the stockholders to fill a directorship. With respect to an incumbent director whom the directors are considering as a potential nominee for re-election, the directors review and consider the incumbent director’s service during his or her term, including the number of meetings attended, level of participation, and overall contribution to the Board. The manner in which the directors evaluate a potential nominee will not differ based on whether the candidate is recommended by our directors or stockholders.

We consider the following qualifications, among others, when making a determination as to whether a person should be nominated to our Board: the independence of the director nominee; the nominee’s character and integrity; financial literacy; level of education and business experience, including experience relating to biopharmaceutical companies; whether the nominee has sufficient time to devote to our Board; and the nominee’s commitment to represent the long-term interests of our stockholders. We review candidates in the context of the current composition of the Board and the evolving needs of our business. We believe that each of the current members of our Board has the requisite business, biopharmaceutical, financial or managerial experience to serve as a member of the Board, as described above in their biographies under the heading “Information about our Executive Officers” and “Information about our Non-Employee Directors.” We also believe that each of the current members of our Board has other key attributes that are important to an effective board, including integrity, high ethical standards, sound judgment, analytical skills, and the commitment to devote significant time and energy to service on the Board and its committees.

Code of Business Conduct and Ethics

We have adopted a Code of Ethics (the “Code”), which applies to all of our directors and employees, including our principal executive officer and principal financial officer. The Code includes guidelines dealing with the ethical handling of conflicts of interest, compliance with federal and state laws, financial reporting, and our proprietary information. The Code also contains procedures for dealing with and reporting violations of the Code. We have posted a copy of the Code on our website, located at www.mustangbio.com.

Insider Trading Policy; Policy Prohibiting Hedging and Speculative Trading

We have adopted an Insider Trading Policy that governs the purchase, sale, and other dispositions of our securities on the basis of material non-public information by directors, officers, employees, consultants and contractors. We believe these policies and procedures are reasonably designed to promote compliance with insider trading laws, rules and regulations, and applicable Nasdaq listing standards. A copy of our Insider Trading Policy is filed as an exhibit to this Form 10-K.

Pursuant to our Insider Trading Policy, our officers, directors, and employees are also prohibited from engaging in speculative trading, including hedging transactions or short sale transactions with respect to our securities.

Delinquent Section 16(a) Reports

Section 16 of the Exchange Act requires our directors, certain officers, and beneficial owners of more than ten percent of our common stock to file reports with the SEC indicating their holdings of and transactions in our equity securities, and to provide copies of such reports to us. Based solely on a review of our records, publicly available information, and written representations by the persons required to file such reports, we believe that during the fiscal year ended December 31, 2025, there were no delinquent Section 16(a) filings.

Item 11.Executive Compensation

Named Executive Officers

As determined in accordance with SEC rules, our named executive officers (“NEOs”), which includes all executive officers serving during 2025, are the individuals set forth below:

●Manuel Litchman, M.D., our President, Chief Executive Officer, and Interim Chief Financial Officer.

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The following table sets forth information concerning compensation paid by us to our NEOs for their services rendered to us in all capacities during the years ended December 31, 2025, and 2024.

Summary Compensation Table

Non-Equity

Stock Option Incentive Plan All Other

____________________

Narrative to Summary Compensation Table

Employment Agreements

Dr. Litchman

In April 2017, we entered into an employment agreement with Dr. Litchman, our President, Chief Executive Officer and Interim Chief Financial Officer, pursuant to which he received an initial annual base salary of $395,000. As part of his annual review in January 2023, the Board increased Dr. Litchman’s annual base salary to $485,500 effective as of April 1, 2023. There were no increases to Dr. Litchman’s annual base salary in 2025 and 2024. The employment agreement further provides eligibility for an incentive bonus linked to the realization of certain corporate milestones to be established annually by the Board or the Compensation Committee. Dr. Litchman’s target annual bonus is equal to fifty percent (50%) of his annual salary, and the Board or the Compensation Committee will determine the actual payout amount each year. The employment agreement provides that if we terminate Dr. Litchman without cause or if he resigns for good reason, as those terms are defined in the employment agreement, he will be entitled to: (i) severance payments at a rate equal to his base salary then in effect for a period of 12 months following his termination date; (ii) a pro-rata share of the annual incentive bonus for the year in which the termination occurred, to be paid when and if such bonus would have been paid under the employment agreement; (iii) accelerated partial vesting of all unvested time-based equity awards with respect to the same number of shares that would have vested if Dr. Litchman had continued in employment for one year following the termination date; and (iv) if Dr. Litchman timely elects continued health insurance coverage under COBRA, the entire premium necessary to continue such coverage for Dr. Litchman and Dr. Litchman’s eligible dependents until the conclusion of the time when Dr. Litchman is receiving continuation of base salary payments or until Dr. Litchman becomes eligible for group health insurance coverage under another employer’s plan, whichever occurs first, provided however that we have the right to terminate such payment of COBRA premiums on behalf of Dr. Litchman and instead pay him a lump sum amount equal to the COBRA premium times the number of months remaining in the specified period if we determine in our discretion that continued payment of COBRA premiums is or may be discriminatory under Section 105(h) of the Internal Revenue Code. In addition, if Dr. Litchman is terminated without cause or resigns for good reason within twelve months following a change in control, he will be entitled to the severance benefits described in (i), (ii) and (iv) of the immediately preceding sentence, as well as 100% accelerated vesting of the options and other equity awards granted to him. In the event Dr. Litchman’s employment is terminated due to his death or disability, he or his estate will receive continuing salary payments for ninety days and a pro-rata share of the annual incentive bonus for the year in which the termination occurred, to be paid when and if such bonus would have been paid under the employment agreement. In each case, the severance benefits are conditioned upon Dr. Litchman’s execution and non-revocation of a release of claims against us and compliance with certain non-solicitation and non-competition covenants during his employment and for a period of six months thereafter. Also, the severance benefits are subject to reduction to avoid the imposition of excise taxes under Sections 280G and 4999 of the Code, if such reduction would result in a better after-tax result for Dr. Litchman.

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Annual Cash Incentive Bonus

In 2025, Dr. Litchman was eligible to earn a target annual cash incentive equal to 50% of his base salary per the terms of his Employment Agreement.

Dr. Litchman’s annual cash incentive bonus is based upon our performance against pre-established corporate goals and objectives, which included a combination of clinical and nonclinical goals related to our products as well as other corporate development goals, and his individual performance based upon subjective performance reviews. In 2025, the Compensation Committee decided not to pay the 2025 annual cash incentive bonus to preserve our cash resources.

Equity Awards

The Company maintains the Mustang Bio, Inc. 2016 Incentive Plan (the “2016 Plan”), pursuant to which it may, from time to time, grant equity awards to its service providers, including its executive officers and directors. However, no equity awards were granted in 2025.

Outstanding Equity Awards at Fiscal Year-Ended December 31, 2025

Option Awards Stock Awards

Market Value

Number of Number of Number of of Shares or

securities securities Shares or Units of Stock

underlying underlying Option Units of That Have

unexercised unexercised exercise Option Stock That Not

options (#) options (#) price Expiration Have Not Vested(1)

__________________

(3) These restricted stock units vest as follows: (i) 46 shares will vest on April 24, 2026; and (ii) 25 shares will vest on April 24, 2027, subject in each case to Dr. Litchman’s continuous service to the Company through that date.

Clawback Policy

Pursuant to Nasdaq listing requirements, we have adopted a policy providing for the recovery of erroneously awarded incentive-based compensation received by our executive officers or the executive officers of one of our subsidiaries during an applicable recovery period (the “Clawback Policy”) in compliance with Section 10D of the Exchange Act. Under the Clawback Policy, in the event that financial results upon which a cash or equity-based incentive award was based becomes the subject of a financial restatement that is required because of material non-compliance with financial reporting requirements, the Compensation Committee will conduct a review of awards covered by the Clawback Policy and recoup any erroneously awarded incentive-based compensation to ensure that the ultimate award reflects the financial results as restated. The Clawback Policy covers any cash or equity-based incentive compensation award that was paid, earned or granted to covered executive officers during the last completed three fiscal years immediately preceding the date on which we are required to prepare the accounting restatement.

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Stock Option Grant Policy

We did not grant stock options or similar instruments to our NEOs during 2025. We have no set policy or practice regarding the timing of stock option awards or similar instruments in relation to the disclosure of material nonpublic information. In general, the timing of stock option awards is dictated by the event or circumstance giving rise to the award and the schedules of the directors responsible for approving the award. If, in the future, a stock option grant is made at a time that material nonpublic information exists, the directors approving the award would be responsible for considering the anticipated effect of that information on our stock price and would take such effect into account when sizing and pricing the award.

Director Compensation

Directors who are also employees are not compensated separately for serving on the Board or any of its committees. For 2025, our only employee director was Dr. Litchman, and he is therefore not included in the Director Compensation Table below.

Each of our non-employee directors is eligible to receive cash and equity compensation for his or her services. The Compensation Committee periodically conducts reviews of peer company director compensation practices, including before considering changes to our director compensation program and amounts.

Director Compensation Program

In January 2016, the Board adopted a Non-Employee Directors Compensation Plan for our non-employee directors, which determines the cash and equity compensation payable to our non-employee directors. The Non-Employee Directors Compensation Plan provides for our non-employee directors to receive the following compensation:

Cash Compensation:

● $50,000 annual retainer; and

● $10,000 additional annual retainer for the Audit Committee Chair.

However, for Mr. Weiss, in lieu of the cash compensation described above, $60,000 of annual cash compensation is paid to the Advisor according to the Advisory Agreement.

Equity Compensation:

However, in 2025 the Board decided not to grant director equity awards due to timing of the annual shareholders meeting.

In addition, each non-employee director receives reimbursement for reasonable travel expenses incurred in attending meetings of our Board and meetings of committees of our Board.

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Director Compensation Table

The following table sets forth the cash and other compensation we paid to the non-employee members of our Board for all services in all capacities during 2025.

Fees Earned or Stock

Paid in Cash Awards Total

Name ($)(1) ($)(2) ($)

Lindsay A. Rosenwald, M.D. 50,000 — 50,000

Michael J. Zelefsky, M.D. 50,000 — 50,000

____________________

Item 12.Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Securities Authorized for Issuance Under Equity Compensation Plans

The following table contains information about our equity compensation plans as of December 31, 2025.

Equity Compensation Plan Information

Number of securities

remaining available

Weighted- for future issuance

average under equity

Number of securities to be exercise price of compensation plans

issued upon exercise of outstanding (excluding securities

outstanding options, options, warrants reflected in

Plan Category warrants and rights and rights(1) column (a))

(a) (b) (c)

Equity compensation plans not approved by security holders — — —

(1) The calculation of the weighted-average exercise price of outstanding options, warrants and rights in this column does not include outstanding restricted stock units, as they do not have an exercise price.

Our equity compensation plans consist of the 2016 Plan, and the Mustang Bio, Inc. 2019 Employee Stock Purchase Plan, which were each approved by our stockholders. We do not have any equity compensation plans or arrangements that have not been approved by our stockholders.

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Security Ownership of Our Directors, Executive Officers, and 5% Beneficial Owners

The following table shows information, as of March 17, 2026, concerning the beneficial ownership of our common stock by:

● each of our current directors;

● each of our NEOs shown in our Summary Compensation Table; and

● all current directors and executive officers as a group.

As of March 17, 2026, there were 6,732,092 shares of our common stock, 845,385 shares of our Class A common stock, and 250,000 shares of our Class A Preferred Stock outstanding. In order to calculate a stockholder’s percentage of beneficial ownership, we include in the calculation those shares underlying options or warrants beneficially owned by that stockholder that are vested or that will vest within 60 days of March 16, 2026. Shares of restricted stock are deemed to be outstanding. Options or warrants held by other stockholders that are not attributed to the named beneficial owner are disregarded in this calculation. Beneficial ownership is determined in accordance with the rules of the SEC and includes voting or investment power with respect to the shares of our common stock. Unless we have indicated otherwise, each person named in the table below has sole voting power and investment power for the shares listed opposite such person’s name, except to the extent authority is shared by spouses under community property laws.

Shares Under

Exercisable

Options and

Unvested Total Shares

Restricted Stock Beneficially

Name of Beneficial Owner (1) Shares owned Units(2) Owned % of total CS

Michael S. Weiss (3) 991 — 991 * %

Lindsay A. Rosenwald, M.D (3) 1,008 — 1,008 * %

Neil Herskowitz 145 — 145 * %

Adam J. Chill 375 — 375 * %

Michael J. Zelefsky, M.D 379 — 379 * %

David Jin 286 — 286 * %

5% or Greater Stockholders:

_________________

* Less than 1% of our common stock outstanding

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The following table shows information, as of March 17, 2026, concerning the beneficial ownership of our Class A Common Stock:

Class A Common StockBeneficially Owned

____________________

(2) Converts into 1,127 shares of common stock.

The following table shows information, as of March 17, 2026, concerning the beneficial ownership of our Class A Preferred Stock:

Class A Preferred StockBeneficially Owned

____________________

(2) Converts into 333 shares of common stock.

Item 13.Certain Relationships and Related Transactions, and Director Independence

Except as set forth below, since January 1, 2024, we have not been a party to any transaction in which the amount involved exceeded or will exceed $120,000, and in which any of our directors, NEOs, or beneficial owners of more than 5% of our capital stock, or an affiliate or immediate family member thereof, had or will have a direct or indirect material interest, and other than compensation, termination, and change-in-control arrangements.

The written charter of the Audit Committee authorizes, and Nasdaq rules require, the Audit Committee to review and approve related-party transactions. In reviewing related-party transactions, the Audit Committee applies the basic standard that transactions with affiliates should be made on terms no less favorable to us than could have been obtained from unaffiliated parties. Therefore, the Audit Committee reviews the benefits of the transactions, terms of the transactions and the terms available from unrelated third parties, as applicable. All transactions other than compensatory arrangements between us and our officers, directors, principal stockholders and their affiliates will be approved by the Audit Committee or a majority of the disinterested directors and will continue to be on terms no less favorable to us than could be obtained from unaffiliated third parties.

Founders Agreement and Management Services Agreement with Fortress

Effective March 13, 2015, we entered a Founders Agreement with Fortress, which was amended and restated on May 17, 2016, and again on July 26, 2016 (the “Mustang Founders Agreement”). The Mustang Founders Agreement provides that, in exchange for the time and capital expended in the formation of our company and the identification of specific assets the acquisition of which result in the formation of a viable emerging growth life science company, Fortress loaned $2.0 million, representing the up-front fee required to acquire our license agreement with COH. The Mustang Founders Agreement has a term of 15 years, which upon expiration automatically renews for successive one-year periods unless terminated by Fortress and the Company or a Change in Control (as defined in the Mustang Founders Agreement) occurs. Concurrently with the second amendment on July 26, 2016, to the Mustang Founders Agreement, Fortress entered into an Exchange Agreement whereby Fortress exchanged its 7.25 million Class B Common shares for 9,333 common shares and 250,000 Class A Preferred shares. Class A Preferred Stock is identical to common stock other than as to voting rights, conversion rights and the Annual Stock Dividend right (as described below). Each share of Class A Preferred Stock is entitled to vote the number of votes that is equal to one and one-tenth (1.1) times a fraction, the numerator of which is the sum of (A) the shares of our outstanding common stock and (B) the whole shares of our

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common stock into which the shares of outstanding Class A common stock and Class A Preferred Stock are convertible and the denominator of which is the number of shares of outstanding Class A Preferred Stock. Thus, the Class A Preferred Stock will at all times constitute a voting majority. Each share of Class A Preferred Stock is convertible, at Fortress’ option, into one fully paid and nonassessable share of our common stock, subject to certain adjustments. As holders of Class A Preferred Stock, Fortress will receive on each January 1 (each a “Annual Stock Dividend Payment Date”) until the date all outstanding Class A Preferred Stock is converted into common stock, pro rata per share dividends paid in additional fully paid and nonassessable shares of common stock (“Annual Stock Dividends”) such that the aggregate number of shares of common stock issued pursuant to such Annual Stock Dividend is equal to two and one-half percent (2.5%) of our fully-diluted outstanding capitalization on the date that is one (1) business day prior to any Annual Stock Dividend Payment Date.

As additional consideration under the Mustang Founders Agreement, we are required to: (i) pay an equity fee in shares of common stock, payable within five (5) business days of the closing of any equity or debt financing that occurs after the effective date of the Mustang Founders Agreement and ending on the date when Fortress no longer has majority voting control in our voting equity, equal to two and one-half (2.5%) of the gross amount of any such equity or debt financing; and (ii) pay a cash fee equal to four and one-half percent (4.5%) of our annual net sales, payable on an annual basis, within ninety (90) days of the end of each calendar year. In the event of a Change in Control, we will pay a one-time change in control fee equal to five (5x) times the product of (A) net sales for the twelve (12) months immediately preceding the change in control and (B) four and one-half percent (4.5%).

Effective as of March 13, 2015, we entered into a Management Services Agreement (the “MSA”) with Fortress, pursuant to which Fortress renders advisory and consulting services to us. The MSA has an initial term of five years and is automatically renewed for successive five-year terms unless terminated in accordance with its provisions. Services provided under the MSA may include, without limitation, (i) advice and assistance concerning any and all aspects of our operations, clinical trials, financial planning and strategic transactions and financings and (ii) conducting relations on our behalf with accountants, attorneys, financial advisors and other professionals (collectively, the “Services”). We are obligated to utilize clinical research services, medical education, communication and marketing services and investor relations/public relation services of companies or individuals designated by Fortress, provided those services are offered at market prices. However, we are not obligated to take or act upon any advice rendered by Fortress and Fortress shall not be liable for any of its actions or inactions based upon their advice. Pursuant to the MSA and our Certificate of Incorporation, Fortress and its affiliates, including all members of our Board, will have no fiduciary or other duty to communicate or present any corporate opportunities to us or to refrain from engaging in business that is similar to that of our company. In consideration for the Services, we pay Fortress an annual consulting fee of $0.5 million (the “Annual Consulting Fee”), payable in advance in equal quarterly installments on the first business day of each calendar quarter in each year, provided, however, that such Annual Consulting Fee shall be increased to $1.0 million for each calendar year in which we have net assets in excess of $100 million at the beginning of the calendar year. We record fifty percent of the Annual Consulting Fee in research and development expense and fifty percent in general and administrative expense in the Statement of Operations. For the years ended December 31, 2025 and 2024, we recorded expense of $0.5 million and $0.5 million, respectively, related to this agreement.

For the year ended December 31, 2025, the Company issued 127,140 shares of common stock to Fortress, which equaled 2.5% of the sum of the gross proceeds of $0.6 million from the sale of shares of common stock under Mustang’s At-the-Market Offering, $8.0 million gross proceeds from the February 2025 Public Offering, and $7.1 million from the July 2025 Series C-2 warrant exercises. The Company recorded an expense of approximately $0.4 million in general and administrative expenses related to these shares for the year ended December 31, 2025.

For the year ended December 31, 2024, the Company issued 23,450 shares of common stock to Fortress, which equaled 2.5% of the sum of the gross proceeds of $2.6 million from the sale of shares of common stock under Mustang’s At-the-Market Offering, $4.0 million gross proceeds from the May 2024 Public Offering, $2.5 million from the June 2024 PIPE, and $4.0 million from the October 2024 warrant exercise. The Company recorded an expense of approximately $0.3 million in general and administrative expenses related to these shares for the year ended December 31, 2024.

Payables and Accrued Expenses Related Party

In the normal course of business, Fortress pays certain expenses on behalf of the Company. Such expenses are recorded as payables and accrued expenses - related party.

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Director Compensation

Dr. Rosenwald and David Jin

Pursuant to the terms of our Non-Employee Directors Compensation Plan, Dr. Rosenwald and Mr. Jin will receive a cash fee of $50,000 per year paid quarterly and an annual stock award of the greater of (i) a number of shares of common stock having a fair market value on the grant date of $50,000 or (ii) 10,000 shares of common stock, which shares shall vest and become non-forfeitable on the third anniversary of the grant date, subject to continued service on the board of directors on such date. However, no restricted stock awards were granted in 2025 or 2024. Dr. Rosenwald is Chairman, President and Chief Executive Officer of Fortress and Mr. Jin is Chief Financial Officer and Head of Corporate Development of Fortress. We are a controlled subsidiary of Fortress.

For the year ended December 31, 2025, we recognized $50,000 and $50,000 for Dr. Rosenwald and Mr. Jin, respectively, in expense related to the director compensation. For the year ended December 31, 2024, we recognized $50,000 and $12,500 for Dr. Rosenwald and Mr. Jin, respectively, in expense in our Statements of Operations related to the director compensation. No restricted stock awards were granted in 2025 and 2024.

Mr. Weiss - Advisory Agreement with Caribe BioAdvisors, LLC

The Board approved and authorized our entrance into an advisory agreement, dated January 1, 2017 (the “Advisory Agreement”), with Caribe BioAdvisors, LLC (the “Advisor”), owned by Michael S. Weiss, the Chairman of the Board, to provide the board advisory services of Mr. Weiss as Chairman of the Board. Pursuant to the Advisory Agreement, the Advisor will be paid an annual cash fee of $60,000, paid quarterly and an annual stock award of the greater of (i) a number of shares of common stock having a fair market value on the grant date of $50,000 or (ii) 10,000 shares of common stock, which shares shall vest and become non-forfeitable on the third anniversary of the grant date, subject to continued service on the Board on such date.

For the year ended December 31, 2025, we recognized $60,000 in expense related to the Advisory Agreement. For the year ended December 31, 2024, we recognized $60,000 in expense in our Statements of Operations related to the Advisory Agreement. No restricted stock awards were granted in 2025 and 2024.

Item 14.Principal Accounting Fees and Services

Audit Fees, Audit-Related Fees, Non-Audit Fees, Tax Fees and Other Fees

Audit Fees

For the year ended December 31, 2025, KPMG LLP billed us an aggregate of approximately $413,000 in fees and professional services rendered in connection with the audit of our annual financial statements included in our Annual Reports on Form 10-K for the 2025 fiscal year, the review of our financial statements included in our Quarterly Reports on Form 10-Q during that fiscal year, and overages incurred for final billings for the 2024 audit.

For the year ended December 31, 2024, KPMG LLP billed us an aggregate of approximately $412,000 in fees and professional services rendered in connection with the audit of our annual financial statements included in our Annual Reports on Form 10-K for the 2024 fiscal year and the review of our financial statements included in our Quarterly Reports on Form 10-Q during that fiscal year.

Audit-Related Fees

For the year ended December 31, 2025, and 2024, KPMG LLP billed us an aggregate of approximately $293,000 and $255,000, respectively, in fees for audit-related services rendered in connection with securities offerings and registration statements, in addition to the fees described above under the heading “Audit Fees.”

Tax Fees

During the fiscal years ended December 31, 2025 and 2024 we were not billed by KPMG LLP for fees for professional services rendered for tax compliance, tax advice, and tax planning services.

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All Other Fees

During the fiscal years ended December 31, 2025 and 2024, we were not billed by KPMG LLP for any fees for services, other than those described above, rendered to us for each of those fiscal years.

Pre-Approval of Services

Our Audit Committee has established a policy setting forth the procedures under which services provided by our independent registered public accounting firm will be pre-approved by our Audit Committee. The potential services that might be provided by our independent registered public accounting firm fall into two categories:

Services that our independent registered public accounting firm may not legally provide include such services as bookkeeping, certain human resources services, internal audit outsourcing, and investment or investment banking advice.

All proposed engagements of our independent registered public accounting firm, whether for audit services or permissible non-audit services, are pre-approved by our Audit Committee. We jointly prepare a schedule with our independent registered public accounting firm that outlines services which we reasonably expect we will need from our independent registered public accounting firm and categorize them according to the classifications described above. Each service identified is reviewed and approved or rejected by our Audit Committee.

PART IV

Item 15.Exhibits, Financial Statement Schedules

(a) Financial Statements.

The following financial statements are filed as part of this Form 10-K:

Financial Statements:

Statements of Operations for the Years Ended December 31, 2025 and 2024 F-5

Statements of Cash Flows for the Years Ended December 31, 2025 and 2024 F-7

Notes to Financial Statements F-8 - F-26

(b) Exhibits.

Exhibit No. Description

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Exhibit No. Description

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Exhibit No. Description

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Exhibit No. Description

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Exhibit No. Description

# Confidential treatment has been requested with respect to omitted portions of this exhibit.

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† Indicates management contract or compensatory plan or arrangement.

** Filed herewith.

*** Furnished herewith.

Item 16.Form 10-K Summary.

None.

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INDEX TO FINANCIAL STATEMENTS

Statements of Operations for the Years Ended December 31, 2025 and 2024 F-5

Statements of Cash Flows for the Years Ended December 31, 2025 and 2024 F-7

Notes to Financial Statements F-8 – F-26

F-1

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Report of Independent Registered Public Accounting Firm

To the Stockholders and Board of Directors

Mustang Bio, Inc.:

Opinion on the Financial Statements

We have audited the accompanying balance sheets of Mustang Bio, Inc. (the Company) as of December 31, 2025 and 2024, the related statements of operations, stockholders’ equity, and cash flows for the years then ended, and the related notes (collectively, the financial statements). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for the years then ended, in conformity with U.S. generally accepted accounting principles.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

Critical audit matters are matters arising from the current period audit of the financial statements that were communicated or required to be communicated to the audit committee and that: (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. We determined that there are no critical audit matters.

/s/ KPMG LLP

We have served as the Company’s auditor since 2021.

Boston, Massachusetts

March 19, 2026

F-2

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MUSTANG BIO, INC.

BALANCE SHEETS

(in thousands, except for share and per share amounts)

December 31, December 31,

ASSETS

Current Assets:

Cash and cash equivalents $ 17,266 $ 6,839

Other receivables 217 402

Prepaid expenses and other current assets 110 200

Property, plant and equipment, held for sale — 1,165

MBIO US Equity

MBIO · 10-K · period ended 2025-12-31

Item 7.Management’s Discussion and Analysis of the Results of Operations

Item 7A.Quantitative and Qualitative Disclosures About Market Risks

Item 8.Financial Statements and Supplementary Data.

Item 9.Changes in and Disagreements with Accountants on Accounting and Financial Disclosure.

Item 9A.Controls and Procedures.

Item 9B.Other Information

Item 9C. Disclosure Regarding Foreign Jurisdiction that Prevents Inspections.

Item 10.Directors, Executive Officers and Corporate Governance

Item 11.Executive Compensation

Item 12.Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13.Certain Relationships and Related Transactions, and Director Independence

Item 14.Principal Accounting Fees and Services

Item 15.Exhibits, Financial Statement Schedules

Item 16.Form 10-K Summary.

MBIO US Equity☆

MBIO · 10-K · period ended 2025-12-31

Item 7.Management’s Discussion and Analysis of the Results of Operations

Item 7A.Quantitative and Qualitative Disclosures About Market Risks

Item 8.Financial Statements and Supplementary Data.

Item 9.Changes in and Disagreements with Accountants on Accounting and Financial Disclosure.

Item 9A.Controls and Procedures.

Item 9B.Other Information

Item 9C. Disclosure Regarding Foreign Jurisdiction that Prevents Inspections.

Item 10.Directors, Executive Officers and Corporate Governance

Item 11.Executive Compensation

Item 12.Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13.Certain Relationships and Related Transactions, and Director Independence

Item 14.Principal Accounting Fees and Services

Item 15.Exhibits, Financial Statement Schedules

Item 16.Form 10-K Summary.

MBIO US Equity