MUSTANG BIO INC

Balance Sheets** (Unaudited)**

(in thousands, except share and per share amounts)

Statements of Operations** (Unaudited)**

(in thousands, except share and per share amounts)

Statements of Stockholders’ Equity (Unaudited)

(in thousands, except share amounts)

Statements of Stockholders’ Equity (Unaudited)

(in thousands, except share amounts)

Statements of Cash Flows** (Unaudited)**

(in thousands)

The accompanying notes are an integral part of these unaudited financial statements

Notes to Unaudited Financial Statements

Note 1 - Organization, Description of Business and Liquidity and Capital Resources

Mustang Bio, Inc. (the “Company” or “Mustang”) was incorporated in Delaware on March 13, 2015. Mustang is a clinical-stage biopharmaceutical company focused on translating medical breakthroughs in cell and gene therapy into potential cures for hematologic cancers and solid tumors. The Company may acquire rights to these technologies by licensing the rights 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.

The Company is a majority-controlled subsidiary of Fortress Biotech, Inc. (“Fortress” or “Parent”).

Liquidity and Capital Resources

The Company has incurred substantial operating losses and expects to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of June 30, 2024, the Company had an accumulated deficit of $394.4 million.

The Company has funded its operations to date primarily through the sale of equity and via debt raises. The Company expects to continue to use the proceeds from its previous financing transactions and asset sale primarily for working capital and general corporate purposes.

The Company will require substantial additional financings through equity and debt offerings, collaborations and licensing arrangements or other sources to fully develop, prepare regulatory filings, obtain regulatory approvals and commercialize its existing product candidates. The continuation of our business as a going concern is dependent upon raising additional capital and eventually attaining and maintaining profitable operations.

In accordance with Accounting Standards Codification (“ASC”) 205-40, Going Concern, the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that these unaudited consolidated financial statements are issued. This evaluation initially does not take into consideration the potential mitigating effect of management’s plans that have not been fully implemented as of the date the financial statements are issued. When substantial doubt exists under this methodology, management evaluates whether the mitigating effect of its plans sufficiently alleviates substantial doubt about the Company’s ability to continue as a going concern. The mitigating effect of management’s plans, however, is only considered if both (1) it is probable that the plans will be effectively implemented within one year after the date that the financial statements are issued, and (2) it is probable that the plans, when implemented, will mitigate the relevant conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that these unaudited financial statements are issued. In performing its evaluation, management excluded certain elements of its operating plan that cannot be considered probable. Under ASC 205-40, the future receipt of potential funding from future equity or debt issuances cannot be considered probable at this time because these plans are not entirely within the Company’s control nor have been approved by the Board of Directors as of the date of these financial statements.

The Company's expectation to generate operating losses and negative operating cash flows in the future, and the need for additional funding to support its planned operations raise substantial doubt regarding the Company’s ability to continue as a going concern for a period of one year after the date that these unaudited financial statements are issued. The Company made strategic decisions, including a significant reduction in the workforce by approximately 81% in April 2024, and also in April 2024, terminated certain license agreements with St. Jude and Leiden University Medical Centre, and with Mayo Clinic in June 2024, to preserve capital and prioritize the allocation of resources. The Company continues to pursue additional cash resources through public or private equity or debt financings. The Company has concluded that substantial doubt exists about the Company’s ability to continue as a going concern for a period of at least 12 months from the date of issuance of these unaudited financial statements.

The accompanying unaudited financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business. The financial statements do not include

any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that may be necessary if the Company is unable to continue as a going concern.

Note 2 - Significant Accounting Policies

Basis of Presentation

The accompanying interim unaudited financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, the interim unaudited financial statements reflect all adjustments, which include only normal recurring adjustments necessary for the fair statement of the balances and results for the periods presented. They do not include all of the information and footnotes required by GAAP for complete financial statements. Therefore, these financial statements should be read in conjunction with the Company's audited financial statements and notes thereto for the year ended December 31, 2023, which were included in the Company’s Annual Report on Form 10-K and filed with the Securities and Exchange Commission (“SEC”) on March 11, 2024 (the “2023 Form 10-K”). The results of operations for any interim periods are not necessarily indicative of the results that may be expected for the entire fiscal year or any other interim period.

Use of Estimates

The Company’s unaudited financial statements include certain amounts that are based on management’s best estimates and judgments. The Company’s significant estimates include, but are not limited to, assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Due to the uncertainty inherent in such estimates, actual results could differ from those estimates.

Cash, Cash Equivalents and Restricted Cash

The Company records cash held in an escrow account as a security deposit for the manufacturing facility in Worcester, Massachusetts, as restricted cash.

The following table provides a reconciliation of cash, cash equivalents, and restricted cash from the Unaudited Balance Sheets to the Unaudited Statements of Cash Flows for the six months ended June 30, 2024, and 2023:

Assets Held for Sale

Assets held for sale represent assets that have met the criteria of “held for sale” accounting, as specified by Accounting Standards Codification (“ASC”) 360, “Long-lived Assets.” As of June 30, 2024, there were$2.2 million of lab and cell processing equipment, furniture and fixtures and computer equipment that are recorded as assets held for sale. The effect of suspending depreciation on the assets held for sale is immaterial to the results of operations. The assets held for sale are part of the repurchase of assets from uBriGene (see Note 6).

Impairment of Long-Lived Assets

The Company reviews long-lived assets, including tangible assets and other intangible assets with definitive lives, for impairment whenever events or changes in circumstances indicate that the asset’s carrying amount may not be recoverable. The Company conducts its long-lived asset impairment analyses in accordance with ASC 360-10, "Impairment or Disposal of Long-Lived Assets. ASC 360-10-15 requires the Company to group assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the sum of the undiscounted future cash flows. If the undiscounted cash flows do not indicate the carrying amount of the asset group is recoverable, an impairment charge is measured as the amount by which the carrying amount of the asset group exceeds its fair value based on discounted cash flow analysis or appraisals.

Significant Accounting Policies

There have been no material changes to the Company’s significant accounting policies previously disclosed in the 2023 Form 10-K.

Recently Issued Accounting Standards

As of June 30, 2024, there were no new accounting pronouncements or updates to recently issued accounting pronouncements disclosed in the 2023 Form 10-K that affect the Company’s present or future results of operations, overall financial condition, liquidity, or disclosures upon adoption.

Note 3 - Clinical Trial and Sponsored Research Agreements

Research and Development Expenses - Sponsored Research and Clinical Trial Agreements

For the three and six months ended June 30, 2024 and 2023, the Company recorded the following expenses in research and development for sponsored research and clinical trial agreements in the Unaudited Statements of Operations pursuant to the terms of these agreements:

(1) Licenses and associated sponsored research agreements were terminated in May 2023.

(2) License and associated Data Transfer Agreement were terminated in April 2024.

(3) License and associated sponsored research agreement were terminated in June 2024.

Ongoing Clinical Trial and Sponsored Research Agreements

IL13Rα2 (MB-101) Clinical Research Support Agreements

Since February 2017, the Company has been party to a clinical research support agreement for the IL13Rα2-directed CAR T program (the “IL13Rα2 CRA”) with COH, whereby, the Company has agreed to contribute $0.1 million related to patient costs in connection with the on-going investigator-initiated study.

Since October 2020, the Company has been party to a clinical research support agreement for the IL13Rα2-directed CAR T program for adult patients with leptomeningeal glioblastoma, ependymoma or medulloblastoma (the “IL13Rα2 Leptomeningeal CRA”) with COH, whereby the Company has agreed to contribute $0.1 million per patient in connection with the ongoing investigator-initiated study. Further, the Company agreed to fund approximately $0.2 million annually pertaining to the clinical development of the IL13Rα2-directed CAR T program for this patient population.

Since October 2020, the Company has been party to a Sponsored Research Agreement (“SRA”) with COH to conduct combination studies of a potential IL13Rα2* *CAR (MB-101) and herpes simplex-1 oncolytic virus therapy (MB-108). Pursuant to the SRA, the Company funded research in the amount of $0.3 million for the program. In November 2022, the SRA was amended to include additional funding of $0.6 million.

CD20 (MB-106) Clinical Trial Agreement with Fred Hutchinson Cancer Center

Since July 3, 2017, in conjunction with the CD20 Technology License from Fred Hutchinson Cancer Center (“Fred Hutch”), the Company has been party to an investigator-initiated clinical trial agreement (the “CD20 CTA”) to provide partial funding for a Phase 1/2 clinical trial at Fred Hutch evaluating the safety and efficacy of the CD20 Technology in patients with relapsed or refractory B-cell non-Hodgkin lymphomas. In connection with the CD20 CTA, the Company agreed to fund up to $5.3 million of costs associated with the clinical trial, which commenced during the fourth quarter of 2017. In November 2020, the CD20 CTA was amended to include additional funding of approximately $1.8 million, which includes $0.8 million for the treatment of five patients with chronic lymphocytic leukemia. In January 2022, the CD20 CTA was amended to include additional funding of $2.2 million increasing the total payment obligation of the Company in connection with the CD20 CTA not to exceed $9.3 million.

Terminated Clinical Trial and Sponsored Research Agreements

CS1 (MB-104) Clinical Research Support Agreement

Beginning in June 2020, the Company was party to a clinical research and support agreement with COH in connection with an investigator-sponsored study conducted under an Institutional Review Board-approved for MB-104, whereby the Company has agreed to reimburse COH for costs associated with this trial, when incurred, not to exceed $2.4 million. The agreement will expire upon the delivery of a final study report or earlier. Since inception, the Company has reimbursed COH $2.2 million. In May 2023, the Company determined to discontinue development of its MB-104 program and terminated the associated CRA and license.

PSCA (MB-105) Clinical Research Support Agreement

Beginning in October 2020, the Company was party to a clinical research support agreement with COH in connection with an investigator-sponsored study conducted under an Institutional Review Board-approved, investigator-initiated protocol entitled: “A Phase 1 Study to Evaluate PSCA-Specific Chimeric Antigen Receptor (CAR)-T Cells for Patients with Metastatic Castration Resistant Prostate Cancer” for MB-105. The Company has agreed to reimburse COH for costs associated with this trial not to exceed $2.3 million. The agreement will expire upon the delivery of a final study report or earlier. Since inception, the Company has reimbursed COH $0.5 million. In May 2023, the Company determined to discontinue development of its MB-105 program and terminated the associated CRA and license.

XSCID (MB-107) Data Transfer Agreement with St. Jude Children’s Research Hospital

Since June 2020, the Company has been party to a Data Transfer Agreement with St. Jude Children’s Research Hospital (“St. Jude”) under which Mustang will reimburse St. Jude for costs associated with St. Jude’s clinical trial for the treatment of infants with X-linked severe combined immunodeficiency (“XSCID”), whereby the Company will continue to reimburse St. Jude for costs incurred in connection with this trial. In April 2024, the Company terminated its license agreement and the associated Data Transfer Agreement with St. Jude, in exchange for a mutual release of liability and forgiveness by St. Jude of all amounts previously owed by the Company.

RAG1-SCID (MB-110) Sponsored Research Support Agreement (“SRA”) with Leiden University Medical Centre

Since September 8, 2021, in connection with the Leiden License, the Company has been party to a Sponsored Research Support Agreement (“SRA”) with Leiden University Medical Centre (“LUMC”) under which the Company will fund research in the amount of approximately $0.5 million annually over a period of 5 years. The research performed pursuant to this agreement will support technology the Company has licensed from Leiden for the use of a gene therapy under development for the treatment of severe immunodeficiency caused by mutations in theRAG1 gene. In April 2024, the Company delivered a termination notice to LUMC, pursuant to which it terminated the license agreement underpinning the MB-110 product candidate; the Company is currently in discussions with LUMC regarding the terms that will govern such termination.

Sponsored Research Support Agreement with Mayo Clinic

From June 2021 until June 2024, the Company was party to an SRA with the Mayo Clinic under which the Company would fund research in the amount of $2.1 million over a period oftwo years. In October 2022, the SRA was amended to include additional funding of approximately $0.1 million. The research performed pursuant to this agreement supported technology the Company licensed from Mayo Clinic for a novel technology that may be able to transform the administration of CAR T therapies and has the potential to be used as an off-the-shelf therapy. In June 2024, the Company terminated its license agreement and associated SRA with the Mayo Clinic, in exchange for a mutual release of liability and forgiveness by Mayo Clinic of all amounts previously owed by the Company.

Note 4 - Related Party Agreements

Founders Agreement and Management Services Agreement with Fortress

With respect to the Company’s Management Services Agreement (the “Management Services Agreement”) with Fortress for the three and six months ended June 30, 2024 and 2023, expenses related to the MSA are recorded 50% in research and development expenses and 50% in general and administrative expenses in the Unaudited Statements of Operations. For the three months ended June 30, 2024 and 2023, the Company recorded expense of $0.1 million and $0.1 million, respectively, related to the MSA. For the six months ended June 30, 2024 and 2023, the Company recorded expense of $0.3 million and $0.3 million, respectively.

Under the terms of the Second Amended and Restated Founders Agreement (the “Founders Agreement”), which became effective July 22, 2016, Fortress will receive a grant of shares of the Company’s common stock equal to two and one-half percent (2.5%) of the gross amount of any equity or debt financing. For the six months ended June 30, 2024, the Company issued 575,191 shares to Fortress in connection with the equity financings. For the three months ended June 30, 2024 and 2023, the Company recorded expense of approximately $163,000 andzero, respectively, in general and administrative expenses related to these shares. For the six months ended June 30, 2024 and 2023, the Company recorded expense of approximately $163,000 andzero, respectively, in general and administrative expenses related to these shares.

Annual Stock Dividend

Pursuant to the Company’s Amended and Restated Certificate of Incorporation, as amended (the “Certificate of Incorporation”), the Company issued 353,086 shares of common stock to Fortress as the Annual Stock Dividend (as such term is defined in the Certificate of Incorporation), representing 2.5% of the fully-diluted outstanding equity of Mustang

on January 2, 2024. This was recorded in the Statement of Stockholders’ Equity at December 31, 2023, as Common stock issuable – Founders Agreement. The Company recorded an expense of approximately $0.5 million in research and development – licenses acquired related to these issuable shares during the year ended December 31, 2023.

Payables and Accrued Expenses Related Party

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

Note 5 – Assets Purchase Agreements

Agreements with uBriGene

On May 18, 2023, the Company entered into an Asset Purchase Agreement (the “Original Asset Purchase Agreement”) with uBriGene (Boston) Biosciences, Inc., a Delaware corporation (“uBriGene”), pursuant to which the Company agreed to sell its leasehold interest in its cell processing facility located in Worcester, Massachusetts (the “Facility”), and associated assets relating to the manufacturing and production of cell and gene therapies at the Facility to uBriGene (the “Transaction”). The Company and uBriGene subsequently entered into Amendment No. 1 to the Original Asset Purchase Agreement, dated as of June 29, 2023 (“Amendment No. 1”), and Amendment No. 2 to the Original Asset Purchase Agreement, dated as of July 28, 2023 (“Amendment No. 2,” and together with the Original Asset Purchase Agreement and Amendment No. 1, the “Prior Asset Purchase Agreement”).

On July 28, 2023, pursuant to the Prior Asset Purchase Agreement, the Company completed the sale of all of its assets that primarily relate to the manufacturing and production of cell and gene therapies at the Facility (such operations, the “Transferred Operations” and such assets, the “Transferred Assets”) to uBriGene for upfront consideration of $6 million cash (the “Base Amount”). The Transferred Assets included all of the Company’s assets, except for the Company’s lease and related leasehold improvements of the Facility and contracts that are primarily used in the Transferred Operations. The Company recorded a gain of $1.4 million in connection with the sale of the Transferred Assets, and recorded approximately $0.3 million of the base consideration as deferred income, that was to be recognized upon the transfer of the lease.

In connection with the Prior Asset Purchase Agreement, the Company and uBriGene submitted a voluntary joint notice to the U.S. Committee on Foreign Investment in the United States (“CFIUS”). Following CFIUS’s review and subsequent investigation of the transactions related to the Prior Asset Purchase Agreement, on May 13, 2024, the Company, together with uBriGene and CFIUS, executed a National Security Agreement (the “NSA”), pursuant to which the Company and uBriGene agreed to abandon the transactions related to the Prior Asset Purchase Agreement and the agreements entered into in connection therewith. The NSA obligated uBriGene and the Company to terminate agreements between thetwo parties, including the Manufacturing Services Agreement, Quality Services Agreement, and Subcontracting CDMO Agreement. In addition, uBriGene must sell, or otherwise dispose of, the equipment assets purchased within 180 days after the execution of the NSA.

June 2024 Repurchase of Assets

On June 27, 2024 (the “Effective Date”), the Company entered into an Asset Purchase Agreement (the “Repurchase Agreement”) with uBriGene, pursuant to which the Company agreed, subject to the terms and conditions set forth therein, to repurchase the Transferred Assets, primarily lab equipment and supplies, (collectively, the “Repurchased Assets”). Pursuant to the terms of the Repurchase Agreement, the Company and uBriGene also terminated existing manufacturing and services agreements.

As consideration for the Repurchase Agreement, the Company agreed to pay to uBriGene a total purchase price (the “Purchase Price”) of $1.4 million, consisting of (i) an upfront payment of $0.1 million due within five (5) business days of the Effective Date and a (ii) subsequent amount of $1.3 million due on the date that istwelve (12) months after the closing date (the “Deferred Amount”). In the event that as of the original (or any extended) date on which the Deferred Amount is payable, the Company has, as of the date of the public reporting of its then-most recent quarterly audited or

unaudited financial statements, net assets below $20 million, then the Company may, upon written notice to uBriGene, elect to delay its payment obligation of the Deferred Amount by an additionalsix (6) months, with no limit on the number of such extensions available to the Company. Notwithstanding the foregoing, if the Company has not paid the Deferred Amount in full as of the date that istwelve (12) months after closing of the Repurchase Agreement, any amounts that remain outstanding will accrue interest at a rate of 5% per annum beginning on the date that istwelve (12) months after closing and until the Deferred Amount is paid in full. Additionally, in connection with the termination of the agreements described above under the Repurchase Agreement, the Company agreed to forgive a net receivable from uBriGene of approximately $3.3 million, comprised of outstanding receivables of $6.9 million and payables of $3.6 million, resulting in total purchase consideration in the Repurchase Transactions of approximately $4.7 million. As of June 30, 2024, the $1.4 million Purchase Price was recorded in Accrued Other Expenses (see Note 7).

The Company allocated the total purchase consideration of $4.7 million to the Repurchased Assets on a relative fair value basis. The Company used a third-party to perform a valuation of the repurchased equipment, which resulted in a fair value less costs to sell of approximately $2.2 million. The remaining purchase consideration of $2.5 million was allocated to the supplies repurchased. The supplies repurchased with no alternative future use were recognized as research and development expense in an amount of $2.2 million. Repurchased supplies with an alternative future use of $0.3 million were also recognized in research and development expense, as the Company does not have plans to resume operations in the facility, and it intends to dispose of the supplies in a single transaction with the equipment. The Company concluded that the disposal group, which includes the repurchased equipment assets and associated supplies, with an aggregate value of approximately $2.2 million met the criteria to be classified as held for sale at the date of acquisition.

Note 6 – Property, Plant and Equipment, and Asset Impairment

At June 30, 2024, and December 31, 2023, property, plant and equipment consisted of the following:

Depreciation expense for the three months ended June 30, 2024 and 2023, was approximately $0.3 million and $0.6 million, respectively, and was recorded in research and development expense in the Unaudited Statements of Operations. Depreciation expense for the six months ended June 30, 2024 and 2023, was approximately $0.6 million and $1.3 million, respectively, and was recorded in research and development expense in the Unaudited Statements of Operations.

Impairment of Long-Lived Assets

During the three months ended June 30, 2024, The Company concluded it had a triggering event requiring assessment of impairment for certain leasehold improvements and the related right-of-use asset. The Company assessed the carrying value of the asset group consisting of the leasehold improvements and right-of-use asset in accordance with ASC 360, given the significant changes to the Company’s operations, operating cash and the repurchase of equipment. The assessment of the recoverability of the asset group concluded that there was impairment on the carrying value of the asset group of approximately $2.6 million, which was allocated on a pro rata basis using the relative carrying amounts of the assets. Approximately $2.2 million of the impairment loss was allocated to the leasehold improvements, with the remaining $0.4 million allocated to the right-of-use asset.

Note 7 - Accounts Payable and Accrued Expenses

At June 30, 2024, and December 31, 2023, accounts payable and accrued expenses consisted of the following:

(1) Other includes approximately $1.4 million of accrued consideration for the uBriGene Asset Purchase Agreement, see Note 5.

Note 8 – Notes Payable

On April 11, 2023, the Company’s long-term debt facility (the “Term Loan”) with Runway Growth Finance Corp. (“Runway”), originally entered into on March 4, 2023, was terminated upon receipt by Runway of a payoff amount of $30.4 million from the Company comprised of principal, interest and the applicable final payment amount. The loss on extinguishment was recorded in interest expense in the Unaudited Statements of Operations. For the three and six months ended June 30, 2024 and 2023, the Company recorded the following components in interest expense:

The Term Loan accrued interest at a variable annual rate equal to 8.75% plus the greater of (i)0.50% and (ii) the three month LIBOR Rate for U.S. dollar deposits; provided that the Applicable Rate would not be less than 9.25%. On December 7, 2022, the Company entered into the First Amendment (the “First Amendment”) to the Loan Agreement by and between the Company and Runway. The First Amendment amended certain definitions and other provisions of the Loan Agreement to replace LIBOR-based benchmark rates applicable to loans outstanding under the Loan Agreement with SOFR-based rates, subject to adjustments as specified in the First Amendment. The Applicable Rate at March 31, 2023 was 13.77%. For the three and six months ended June 30, 2023, the Company made interest payments of $0.3 million and $1.3 million, respectively, recorded in interest expense in the Unaudited Statements of Operations.

Amortization of the debt discount associated with the Term Loan was approximately $0.1 million for the three and six months ended June 30, 2023, and was recorded in interest expense in the Unaudited Statements of Operations.

In addition, the Term Loan was secured by a lien on substantially all of the Company’s assets other than certain intellectual property assets and certain other excluded collateral, and it contained a minimum liquidity covenant and other covenants that included among other items: (i) limits on indebtedness, and (ii) repurchase of stock from employees, officers and directors.

Note 9 - Stockholders’ Equity

Registration Statements

On April 23, 2021, the Company filed a shelf registration statement on Form S-3 (File No. 333-255476) (the “2021 S-3”), which was declared effective on May 24, 2021. Under the 2021 S-3, the Company was able to sell up to a total of $200.0 million of its securities. The 2021 S-3 expired on May 24, 2024. The Company sold approximately $4.4 million of securities under the 2021 S-3.

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 June 30, 2024, approximately $37.5 million of the 2024 S-3 remains available for sales of securities. The 2024 S-3 expires on June 12, 2027.

As of the filing of this Form 10-Q, 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.

May 2024 Public Offering

On April 29, 2024, the Company commenced a best efforts public offering with an institutional investor (the “Investor”) (the “May 2024 Offering”) of an aggregate of (i)1,160,000 shares of common stock, (ii) pre-funded warrants (the “May 2024 Pre-Funded Warrants”) to purchase up to an aggregate of 15,717,638 shares of common stock (the “May 2024 Pre-Funded Warrant Shares”), (iii) Series A-1 warrants (the “Series A-1 Warrants”) to purchase up to an aggregate of 16,877,638 shares of common stock (the “Series A-1 Warrant Shares”), (iv) Series A-2 warrants (the “Series A-2 Warrants”) to purchase up to an aggregate of 16,877,638 shares of common stock (the “Series A-2 Warrant Shares”), and (v) Series A-3 warrants (the “Series A-3 Warrants,” and together with the Series A-1 Warrants and Series A-2 Warrants, the “Warrants”) to purchase up to an aggregate of 16,877,638 shares of common stock (the “Series A-3 Warrant Shares”). Each share of common stock or May 2024 Pre-Funded Warrant was sold together withone Series A-1 Warrant to purchaseone share of common stock, one Series A-2 Warrant to purchaseone share of common stock, andone Series A-3 Warrant to purchaseone share of common stock. The public offering price for each share of common stock and accompanying Warrants was $0.237, and the public offering price for each May 2024 Pre-Funded Warrant and accompanying Warrants was $0.2369. The May 2024 Pre-Funded Warrants have an exercise price of $0.0001 per share, were exercisable immediately and will expire when exercised in full. Each Warrant has an exercise price of $0.237 per share, will be exercisable beginning on the effective date of stockholder approval of the issuance of the shares upon exercise of the Warrants (the “Warrant Stockholder Approval”). The Series A-1 Warrant will expire on thefive-year anniversary of the Warrant Stockholder Approval. The Series A-2 Warrant will expire on thetwenty-four-month anniversary of the Warrant Stockholder Approval. The Series A-3 Warrant will expire on thenine-month anniversary of the Warrant Stockholder Approval. The Warrants contain customary anti-dilution adjustments to the exercise price, including for share splits, share dividends, rights offering and pro rata distributions.

The net proceeds of the May 2024 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 us, but excluding the net proceeds, if any, from the exercise of the Warrants, was approximately $3.2 million. The May 2024 Offering closed on May 2, 2024.

In connection with the May 2024 Offering, the Company also entered into a warrant amendment agreement (the “Warrant Amendment Agreement”) with the Investor. Under the Warrant Amendment Agreement, the Company agreed to amend certain existing warrants to purchase up to 2,588,236 shares of common stock that were previously issued in October 2023 to the Investor, with an exercise price of $1.58 per share (the “Existing Warrants”), in consideration for their purchase of the securities in the May 2024 Offering, as follows: (i) lower the exercise price of the Existing Warrants to $0.237 per share, (ii) provide that the Existing Warrants, as amended, will not be exercisable until the receipt of Warrant Stockholder Approval for the exercisability of the Warrants in the May 2024 Offering, and (iii) extend the original expiration date of the Existing Warrants byfive years following the receipt of such Warrant Stockholder Approval. The Warrant Amendment Agreement became effective on May 2, 2024.

June 2024 Registered Direct Offering and Concurrent Private Placement of Warrants (the “June 2024 Offering”)

On June 19, 2024, the Company entered into a Securities Purchase Agreement (the “Purchase Agreement”) with an institutional investor (the “June 2024 Investor”), pursuant to whichthe Company agreed to issue and sell, in a registered direct offering priced at-the-market under the rules of Nasdaq (the “Registered Direct Offering”), (i)3,025,000 shares of common stock, at a price per Share of $0.41 and (ii) pre-funded warrants (the “Pre-Funded Warrants”) to purchase up to 3,105,000 shares of our common stock, at a price per Pre-Funded Warrant equal to $0.4099, the price per share of common stock, less $0.0001.

The Pre-Funded Warrants were sold, in lieu of shares of common stockto the June 2024 Investor. The Pre-Funded Warrants have an exercise price of$0.0001 per share, became exercisable upon issuance and remain exercisable until exercised in full.

The Registered Direct Offering closed on June 21, 2024. The Company intends to use the net proceeds of approximately$2.1 million from the Registered Direct Offering for general corporate purposes and working capital requirements.

In a concurrent private placement, pursuant to the terms of the Purchase Agreement, the Company also agreed to issue and sell to the June 2024 Investor unregistered warrants (the “Private Placement Warrants”) to purchase up to 6,130,000 shares of common stock, at an offering price of $0.41 per Private Placement Warrant to purchaseone share of common stock (the “Private Placement” and, together with the Registered Direct Offering, the “Offerings”) (which offering price was included in the purchase price per share of common stock or Pre-Funded Warrant). The Private Placement Warrants have an exercise price of $0.41 per share (subject to customary adjustments as set forth in the Private Placement Warrants), were exercisable upon issuance and will expire five years from the date of issuance. The Private Placement Warrants contain customary anti-dilution adjustments to the exercise price, including for share splits, share dividends, rights offering and pro rata distributions. The Private Placement Warrants were subsequently registered in July 2024 on Form S-1 (File No. 333-280927).

H.C. Wainwright & Co., LLC (“Wainwright” and together with the June 2024 Investor, the “Selling Stockholders”) acted as the exclusive placement agent in connection with the Offerings under an Engagement Letter, dated as of June 18, 2024, between us and Wainwright (the “Engagement Letter”). Pursuant to the Engagement Letter, we issued to Wainwright (or its designees) warrants to purchase up to 367,800 shares of common stock (the “Wainwright Warrants” and, together with the Private Placement Warrants, the “2024 Warrants”). The Wainwright Warrants have substantially the same terms as the Private Placement Warrants, except that the Wainwright Warrants will expire five years from the commencement of the sales of the Offerings and have an exercise price of $0.5125 per share (subject to customary adjustment as set forth in the Wainwright Warrants), representing 125% of the purchase price per share of common stock in the Registered Direct Offering.

At-the-Market Offering

In July 2018, the Company entered into an At-the-Market Issuance Sales Agreement (the “Mustang ATM”) with B. Riley Securities, Inc. (formerly B. Riley FBR, Inc.), Cantor Fitzgerald & Co., National Securities Corporation (now B. Riley FBR, Inc.), and Oppenheimer & Co. Inc. (each an “Agent” and collectively, the “Agents”), relating to the sale of shares of common stock pursuant to the 2020 S-3. Under the Mustang ATM, the Company pays the Agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of common stock. On December 31, 2020, the Mustang ATM was amended to add H.C. Wainwright & Co., LLC as an Agent. On April 14, 2023, the Mustang ATM was amended to add the limitations imposed by General Instruction I.B.6 to Form S-3 and remove Oppenheimer & Co., Inc. as an Agent. On May 31, 2024, the Company delivered notice to the Agents to terminate the Mustang ATM, which was effective June 5, 2024.

On May 31, 2024, the Company entered into an At-the-Market Offering Agreement (the “Offering Agreement”) with H.C. 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 six months ended June 30, 2024 and 2023, no shares of common stock were issued under the Mustang ATM Agreement or the Offering Agreement.

Equity Incentive Plan

The Company has in effect the 2016 Incentive Plan (the “Incentive Plan”). The Incentive Plan was adopted in 2016 by the Company’s stockholders and the compensation committee of the Company’s board of directors and is authorized to grant stock-based awards to directors, officers, employees and consultants. The plan initially authorized grants to issue up to 133,333 shares of authorized but unissued common stock, expires 10 years from adoption, and limits the term of each option to no more than 10 years from the date of grant. In June 2018, the Company’s stockholders approved an amendment to the Incentive Plan to increase the number of authorized shares issuable by 200,000 shares, for a total of 333,333 shares. In June 2021, the Company’s stockholders approved an amendment to the Incentive Plan to increase the number of authorized shares issuable by 200,000 shares, for a total of 533,333 shares. In June 2022, the Company’s stockholders approved an amendment to the Incentive Plan to increase the number of authorized shares issuable by 200,000 shares, for a total of 733,333 shares.

As of June 30, 2024,394,393 shares were available for future issuance under the Incentive Plan.

Stock Options

The following table summarizes stock option activities for the six months ended June 30, 2024:

As of June 30, 2024, the Company hadno unrecognized stock-based compensation expense related to options. The Company accounts for forfeited awards as they occur as permitted.

Restricted Stock

The following table summarizes restricted stock award activities for the six months ended June 30, 2024:

As of June 30, 2024, the Company had unrecognized stock-based compensation expense related to restricted stock of $0.3 million, which is expected to be recognized over the remaining weighted average vesting period of approximately 1.6 years.

Restricted Stock Units

Certain employees and consultants have been awarded restricted stock units with time-based vesting. The following table summarizes restricted stock units’ activities for the six months ended June 30, 2024:

As of June 30, 2024, the Company had unrecognized stock-based compensation expense related to restricted stock units of approximately $57,000, which is expected to be recognized over the remaining weighted average vesting period of approximately 1.9 years.

The following table summarizes stock-based compensation expense for the three and six months ended June 30, 2024 and 2023 (in thousands):

On April 12, 2024, the Company reduced its workforce by approximately 81 percent, which resulted in the forfeiture of a significant number of outstanding restricted stock units and the reversal of previously incurred stock-based compensation expense.

Employee Stock Purchase Plan

Eligible employees can purchase the Company’s common stock at the end of a predetermined offering period at 85% of the lower of the fair market value at the beginning or end of the offering period. The Employee Stock Purchase Plan (“ESPP”) is compensatory and results in stock-based compensation expense. The ESPP was initially authorized in 2019 to sell up to 26,667 shares of authorized but unissued common stock. In June 2021, the Company’s stockholders approved an amendment to the ESPP to increase the number of authorized shares issuable by 40,000 shares. In addition, in June 2023, the Company’s stockholders approved an amendment to the ESPP to increase the number of authorized shares issuable thereunder by 400,000 for a total of 466,667 shares.

As of June 30, 2024,128,352 shares have been purchased and 338,315 shares are available for future sale under the Company’s ESPP.

Warrants

A summary of warrant activities for the six months ended June 30, 2024, is presented below:

Upon the cashless exercise of warrants, the Company will issue new shares of common stock. In connection with the Company’s Registered Direct Offering on October 26, 2023, the Company issued pre-funded warrants to purchase up to 1,668,236 shares of common stock, and in a concurrent private placement, the Company issued unregistered warrants to purchase up to 2,588,236 shares of common stock, and the resale of the underlying shares of common stock were subsequently registered in April 2024 on Form S-1 (File No. 333-275997). In connection with these offerings, H.C. Wainwright received Placement Agent Warrants to purchase up to 155,294 shares of common stock. In connection with the Public Offering the Company completed in May 2024, the 2,588,236 unregistered warrants were repriced from the original exercise price of $1.58 to $0.237.

In connection with the May 2024 Offering, the Company issued pre-funded warrants to purchase up to 15,717,638 shares of common stock and issued three series of warrants to purchase up to 50,632,914 shares of common stock. In connection with these offerings, H.C. Wainwright received Placement Agent Warrants to purchase up to 1,012,658 shares of common stock.

In connection with the Registered Direct Offering, the Company issued pre-funded warrants to purchase up to 3,105,000 shares of common stock, and in the concurrent Private Placement, the Company issued unregistered warrants to purchase up to 6,130,000 shares of common stock, the resale of the underlying shares of common stock were subsequently registered in July 2024 on Form S-1 (File No. 333-280927). In connection with these offerings, H.C. Wainwright received Placement Agent Warrants to purchase up to 367,800 shares of common stock.

During the six months ended June 30, 2024, all of the 1,668,236 pre-funded warrants issued in the October Registered Direct Offering were exercised at an exercise price of$0.001, and all of the 18,822,638 pre-funded warrants issued in the May 2024 Offering and the June Registered Direct Offering were exercised at an exercise price of$0.0001.

Note 10 – Net Loss per Share

Net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period less unvested restricted stock. Since dividends are declared, paid and set aside among the holders of shares of common stock and Class A common shares pro-rata on an as-if-converted basis, the two-class method of computing net loss per share is not required. Diluted net loss per share does not reflect the effect of shares of common stock to be issued upon the exercise of warrants or outstanding Class A preferred shares, as their inclusion would be anti-dilutive. The two-class method is an earnings allocation formula that treats participating securities as having rights that would otherwise have been available to common stockholders. In addition, as our non-pre-funded warrants are participating securities, we are required to calculate diluted earnings per share under the if-converted method and utilize the most dilutive result. In periods where there is a net loss, no allocation of undistributed net loss to non-pre-funded warrants is performed as the holders of our non-pre-funded warrants are not contractually obligated to participate in our losses.

The table below summarizes potentially dilutive securities that were not considered in the computation of diluted net loss per share because they would be anti-dilutive.

Note 11 – Income Taxes

The Company incurred net operating losses and recorded a full valuation allowance against net deferred tax assets for all periods presented. Accordingly, the Company has not recorded a provision for federal or state income taxes.

The Company is subject to US federal and state income taxes. Income tax expense is the total of the current year income tax due or refundable and the change in deferred tax assets and liabilities. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Deferred tax assets are reduced by a valuation allowance when, in the opinion of Management, it is more likely than not that some portion, or all, of the deferred tax asset will not be realized.

Note 12 – Commitments and Contingencies

Indemnification

In accordance with its Certificate of Incorporation, amended and restated bylaws and indemnification agreements, the Company has indemnification obligations to its officers and directors for certain events or occurrences, subject to certain limits, while they are serving at the Company’s request in such capacity. The Company has director and officer insurance to address such claims. The Company also provides indemnification of contractual counterparties in certain situations, including without limitation to clinical sites, service providers and licensors.

Leases

The Company leases office space under an agreement classified as operating leases that expires in October 2026. On June 28, 2024, the Company terminated the lease of its Mercantile Center Facility for a termination fee of $40,000. The Company’s lease liabilities result from the lease of its Plantation Street Facility, which expires in 2026. Such leases do not require any contingent rental payments, impose any financial restrictions, or contain any residual value guarantees. Certain of the Company’s leases include renewal options and escalation clauses; renewal options have not been included in the calculation of the lease liabilities and right of use assets as the Company is not reasonably certain to exercise the options. The Company does not act as a lessor or have any leases classified as financing leases.

At June 30, 2024, the Company identified triggering events that required an impairment of the asset group consisting of the right-of-use asset and associated leasehold improvements. The assessment concluded that impairment existed as of June 30, 2024, and the impairment loss was allocated to the leasehold improvements and right-of-use assets based on the relative carrying amounts of the assets (see Note 6). As of June 30, 2024, the Company had operating lease liabilities of $1.1 million and right of use assets of $0.1 million, which were included in the Unaudited Balance Sheet. At December 31, 2023, the Company had operating lease liabilities of $2.5 million and right of use assets of $1.6 million, which were included in the Unaudited Balance Sheet.

The following summarizes quantitative information about the Company’s operating leases:

Maturities of our operating leases, excluding short-term leases, are as follows: