Exhibit 23.1

Consent of Independent Auditors

We consent to the incorporation by reference in Registration Statement Nos. 333-233594, 333-254310 and 333-258859 on Form S-3 and Registration Statement Nos. 333-222763, 333-241370, 333-258856, 333-265351 and 333-268643 on Form S-8 of Solid Biosciences Inc. of our report dated August 4, 2022 (except for Notes 3, 12 and 14, as to which the date is October 28, 2022), relating to the financial statements of AavantiBio, Inc. as of and for the years ended December 31, 2021 and 2020 appearing in this Current Report on Form 8-K of Solid Biosciences Inc.

/s/ Ernst & Young LLP

Boston, Massachusetts

December 5, 2022

Exhibit 99.1

Solid Biosciences Announces Closing of Acquisition of AavantiBio and Concurrent $75 Million Private Placement

- Transactions create a precision genetic medicine company focused on neuromuscular and cardiac diseases, led by industry veteran Bo Cumbo -

- Company to leverage synergies and key assets, including product candidates for Duchenne muscular dystrophy, Friedreich’s ataxia, BAG3 mediated dilated cardiomyopathy and other undisclosed cardiac diseases, novel capsid libraries, and personnel -

- Combined company has approximately $215 million in cash and investments, which is expected to fund operations into 2025 and support attainment of key milestones for lead gene therapy programs -

CHARLESTOWN, Mass., December 5, 2022 – Solid Biosciences Inc. (Nasdaq: SLDB), a life sciences company focused on advancing meaningful therapies for Duchenne muscular dystrophy (Duchenne), today announced the closing of its acquisition of AavantiBio, a privately held gene therapy company focused on transforming the lives of patients with Friedreich’s ataxia and rare cardiomyopathies, including its pipeline assets and net cash. The combined company will focus on advancing a portfolio of neuromuscular and cardiac programs, including SGT-003, a differentiated gene transfer candidate, for the treatment of Duchenne, AVB-202, a gene transfer candidate for the treatment of Friedreich’s ataxia, AVB-401 for BAG3 mediated dilated cardiomyopathy, and additional assets for the treatment of undisclosed cardiac diseases. Bo Cumbo, the Chief Executive Officer of AavantiBio, will assume the role of President and CEO of Solid Biosciences.

Concurrent with the closing of the merger, Solid closed the previously announced $75 million private placement with a select group of institutional investors and accredited investors. The private placement was led by existing investors Perceptive Advisors, LLC, RA Capital Management and Bain Capital Life Sciences, and other new and existing investors participating in the private placement include CaaS Capital Management, Invus, Laurion Capital Management and Pura Vida Investments.

Solid’s stockholders approved the issuance of shares of Solid common stock in the transactions on December 1, 2022, along with the other proposals presented at the meeting.

Following the closing of the merger and private placement, Solid has total cash and investments of approximately $215 million. Solid expects this will be sufficient to fund the company’s planned operating expenses and capital expenditure requirements into 2025 and enable the potential attainment of key milestones for the combined company’s lead programs.

“The closing of these transactions brings together two companies committed to helping patients and innovations in gene therapy science, bolstered by the capital necessary to advance our lead programs through important developmental milestones,” said Bo Cumbo, President

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and Chief Executive Officer of Solid Biosciences. “We have a pipeline of assets that have the potential to offer unique value to patients, led by gene therapy programs for Duchenne muscular dystrophy, Friedreich’s ataxia and BAG3 mediated dilated cardiomyopathy. With our current cash, we expect to bring the Duchenne program, SGT-003, through to patient dosing, subject to IND clearance; the FA program, AVB-202, to an IND submission; and the BAG3 program, AVB-401, into preclinical testing. We greatly appreciate our stockholders, the Solid and AavantiBio employees and the patient communities who have supported us, and we look forward to the opportunities ahead for the next phase of Solid Biosciences.”

Cumbo continued, “On behalf of the employees and stockholders of Solid, I would like to extend my sincere thanks to Ilan Ganot for his leadership of Solid over the past nearly 10 years and his commitment to bringing innovation to patients with Duchenne and their families.”

BofA Securities acted as the sole placement agent for the private placement made to institutional investors. Wilmer Cutler Pickering Hale and Dorr LLP acted as legal counsel to Solid Biosciences. Sidley Austin LLP acted as legal counsel to AavantiBio.

About Solid Biosciences

Solid Biosciences is a life science company focused on advancing a portfolio of neuromuscular and cardiac programs, including SGT-003, a differentiated gene transfer candidate, for the treatment of Duchenne, AVB-202, a gene transfer candidate for the treatment of Friedreich’s ataxia, AVB-401 for BAG3 mediated dilated cardiomyopathy, and additional assets for the treatment of undisclosed cardiac diseases. Solid aims to be the center of excellence, bringing together those with expertise in science, technology, disease management and care. Disease-focused and founded by those directly impacted by Duchenne, Solid’s mandate is to improve the daily lives of patients living with these devastating diseases. For more information, please visit www.solidbio.com.

About SGT-003

SGT-003 is Solid’s next-generation AAV gene transfer therapy candidate that utilizes a rationally designed, novel muscle-tropic AAV capsid, called AAV-SLB101, to deliver Solid’s proprietary and differentiated nNOS microdystrophin for the treatment of Duchenne. AAV-SLB101 has demonstrated enhanced muscle biodistribution and transgene expression, as well as reduced liver tropism, compared with AAV9 in in vivo mouse models and, utilizing a reporter transgene, non-human primate in vivo models. SGT-003 has correspondingly demonstrated higher levels of microdystrophin expression in vivo in the mdx mouse model of Duchenne and in vitro in human Duchenne cell lines. Solid is targeting an IND submission for SGT-003 in mid-2023.

Forward-Looking Statements

This press release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, including statements regarding future expectations, plans and prospects for the company; the anticipated benefits of the acquisition; the anticipated milestones, business focus and pipeline of the company; the cash runway of the company; the company’s SGT-003 program, including expectations for filing an IND and initiating dosing, AVB-202 program, including expectations for filing an IND, and AVB-401 program; and other statements containing the words “anticipate,” “believe,” “continue,”

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“could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would,” “working” and similar expressions. Any forward-looking statements are based on management’s current expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in, or implied by, such forward-looking statements. These risks and uncertainties include, but are not limited to, risks associated with the ability to recognize the anticipated benefits of the acquisition; the outcome of any legal proceedings that may be instituted against Solid or AavantiBio following any announcement of the acquisition and related transactions; the ability to obtain or maintain the listing of the common stock of the combined company on the Nasdaq Stock Market following the acquisition; the company’s ability to advance its SGT-003, AVB-202, AVB-401 and other programs on the timelines expected or at all; obtain and maintain necessary approvals from the FDA and other regulatory authorities; obtain and maintain the necessary approvals from investigational review boards at clinical trial sites and independent data safety monitoring board; replicate in clinical trials positive results found in preclinical studies and early-stage clinical trials of its product candidates; whether the methodologies, assumptions and applications the company utilizes to assess particular safety or efficacy parameters will yield meaningful statistical results; advance the development of its product candidates under the timelines it anticipates in current and future clinical trials; successfully transition, optimize and scale its manufacturing process; obtain, maintain or protect intellectual property rights related to its product candidates; compete successfully with other companies that are seeking to develop Duchenne and Friedreich’s ataxia treatments and gene therapies; manage expenses; and raise the substantial additional capital needed, on the timeline necessary, to continue development of SGT-003, AVB-202, AVB-401 and other product candidates, achieve its other business objectives and continue as a going concern. For a discussion of other risks and uncertainties, and other important factors, any of which could cause the company’s actual results to differ from those contained in the forward-looking statements, see the “Risk Factors” section, as well as discussions of potential risks, uncertainties and other important factors, in the company’s most recent filings with the Securities and Exchange Commission. In addition, the forward-looking statements included in this press release represent the company’s views as of the date hereof and should not be relied upon as representing the company’s views as of any date subsequent to the date hereof. The company anticipates that subsequent events and developments will cause the company’s views to change. However, while the company may elect to update these forward-looking statements at some point in the future, the company specifically disclaims any obligation to do so.

Investor Contact:

David Carey

FINN Partners

212-867-1768

David.Carey@finnpartners.com

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Media Contact:

Erich Sandoval

FINN Partners

917-497-2867

Erich.Sandoval@finnpartners.com

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Exhibit 99.2

Report of Independent Auditors

To the Stockholders and the Board of Directors of AavantiBio, Inc.

Opinion

We have audited the financial statements of AavantiBio, Inc. (the Company), which comprise the balance sheets as of December 31, 2021 and 2020, and the related statements of operations and comprehensive loss, changes in convertible preferred stock and stockholders’ deficit and cash flows for the years then ended, and the related notes (collectively referred to as the “financial statements”).

In our opinion, the accompanying financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2021 and 2020, and the results of its operations and its cash flows for the years then ended in accordance with accounting principles generally accepted in the United States of America.

Basis for Opinion

We conducted our audits in accordance with auditing standards generally accepted in the United States of America (GAAS). Our responsibilities under those standards are further described in the Auditor’s Responsibilities for the Audit of the Financial Statements section of our report. We are required to be independent of the Company and to meet our other ethical responsibilities in accordance with the relevant ethical requirements relating to our audits. We believe that the audit evidence we have obtained is sufficient and appropriate to provide a basis for our audit opinion.

Responsibilities of Management for the Financial Statements

Management is responsible for the preparation and fair presentation of the financial statements in accordance with accounting principles generally accepted in the United States of America, and for the design, implementation, and maintenance of internal control relevant to the preparation and fair presentation of financial statements that are free of material misstatement, whether due to fraud or error.

In preparing the financial statements, management is required to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern for one year after the date that the financial statements are available to be issued.

Auditor’s Responsibility for the Audit of the Financial Statements

Our objectives are to obtain reasonable assurance about whether the financial statements as a whole are free of material misstatement, whether due to fraud or error, and to issue an auditor’s report that includes our opinion. Reasonable assurance is a high level of assurance but is not absolute assurance and therefore is not a guarantee that an audit conducted in accordance with GAAS will always detect a material misstatement when it exists. The risk of not detecting a material misstatement resulting from fraud is higher than for one resulting from error, as fraud may involve collusion, forgery, intentional omissions, misrepresentations, or the override of internal control. Misstatements are considered material if there is a substantial likelihood that, individually or in the aggregate, they would influence the judgement made by a reasonable user based on the financial statements. In performing an audit in accordance with GAAS, we:

We are required to communicate with those charged with governance regarding, among other matters, the planned scope and timing of the audit, significant audit findings, and certain internal control-related matters that we identified during the audit.

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/s/ Ernst & Young

Boston, Massachusetts

August 4, 2022, except for Notes 3, 12 and 14, as to which the date is October 28, 2022

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AavantiBio, Inc.

Balance Sheets

(in thousands, except share and per share amounts)

See accompanying notes to the financial statements.

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AavantiBio, Inc.

Statements of Operations and Comprehensive Loss

(in thousands)

See accompanying notes to the financial statements.

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AavantiBio, Inc.

Statements of Convertible Preferred Stock and Stockholders’ Deficit

(in thousands, except share amounts)

See accompanying notes to the financial statements.

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AavantiBio, Inc.

Statements of Cash Flows

(in thousands)

See accompanying notes to the financial statements.

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AavantiBio, Inc.

Notes to Financial Statements

1.    Operations

AavantiBio, Inc. (“AavantiBio” or the “Company”) is a gene therapy company focused on transforming the lives of patients with rare genetic diseases. The Company was incorporated on August 14, 2019, under the laws of the state of Delaware, and its principal offices are in Cambridge, Massachusetts.

The Company is subject to risks and uncertainties common to early-stage companies in the biopharmaceutical industry, including, but not limited to, risks related to the successful development and commercialization of product candidates, fluctuations in operating results and financial risks, the ability to successfully raise additional funds when needed, protection of proprietary rights and patent risks, patent litigation, compliance with government regulations, dependence on key personnel and prospective collaborative partners, and competition from competing products in the marketplace.

Liquidity

As of December 31, 2021, the Company had an accumulated deficit of $44.2 million. The Company has incurred losses and negative cash flows from operations since inception, including net losses of $36.6 million and $7.0 million for the years ended December 31, 2021 and 2020, respectively, and expects that its operating losses and negative cash flows will continue for the foreseeable future as the Company continues its research and development (R&D) programs and develop its product candidates.

The Company expects that its cash on hand of $39.9 million as of December 31, 2021, together with the $31.6 million of gross proceeds from the Third Tranche of the Company’s Series A Convertible Preferred Stock financing received on February 24, 2022, will fund operations through at least one year from the date of issuance of these financial statements.

Management also may, in the future, seek to raise additional funds through equity or debt financings or through collaboration transactions. The Company may be unable to obtain equity or debt financings, enter into collaboration transactions and, if necessary, the Company will be required to implement cost reduction strategies. 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 might result from the outcome of this uncertainty.

2.    Summary of Significant Accounting Policies

Basis of Presentation

The accompanying financial statements are presented in accordance with accounting standards generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Use of Estimates

The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Significant estimates made by management relate to, but are not limited to, the fair value of common stock, the fair value of the derivative liability, stock-based compensation, accrued expenses (including accrued and prepaid research costs), and the recoverability of the Company’s net deferred tax assets and related valuation allowance. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable, the results of which form the basis for making judgements about the carrying values of assets and liabilities under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis. Actual results could differ from those estimates.

Concentration of Credit Risks

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company maintains deposits in an accredited financial institution. The Company deposits its cash in financial institutions that it believes have high credit quality and have not experienced any losses in such accounts. The Company does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Such deposits have and will continue to exceed federally insured limits. As of December 31, 2021, and 2020, the Company had deposits in excess of federally insured amounts of $39.9 and $35.7 million, respectively.

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Cash and Cash Equivalents

Cash includes cash in readily available checking accounts. Cash is carried at cost, which approximates its fair value. The Company considers cash and cash equivalents to include short-term, highly liquid investments that are readily convertible to known amounts of cash and so near their maturity that they present an insignificant risk of changes in value, including investments that mature within three months from the date of original purchase.

Property and Equipment

Property and equipment, net, is stated at cost and is depreciated or amortized using the straight-line method over the estimated useful life of the related assets as follows:

Major additions and upgrades are capitalized; maintenance and repairs, which do not improve or extend the life of the respective assets, are expensed as incurred. The Company reviews its property and equipment to determine if any adverse conditions exist or a change in circumstances has occurred that would indicate impairment or a change in the remaining useful life. There have been no impairments in 2021 or 2020.

Leases

Under ASC Topic 840, Leases (“ASC 840”), the Company determines if an arrangement is or contains a lease at inception, and whether the lease is an operating or capital lease. Lease payments made under operating leases are recognized as expense on a straight-line basis over the lease term, resulting in deferred rent classified in other liabilities on the balance sheet.

The Company recognizes leasehold improvements within property and equipment and the corresponding lease incentive as a liability on the balance sheet. The lease incentive is allocated between other current and other long-term liabilities on the balance sheet. The lease incentive liability is recognized as a reduction of rent expense on a straight-line basis over the term of the lease in accordance with ASC 840.

Research and Development Costs

Expenditures for research and development activities are expensed as incurred. The majority of research and development expenses consist of costs incurred in performing research and development activities, including personnel-related expenses such as salaries, facilities costs, depreciation, and external costs of outside vendors engaged to conduct research and preclinical development activities.

Patent Costs

All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses.

Accrued Expenses

The Company accrues expenses related to development activities performed by third parties based on an evaluation of services received and efforts expended pursuant to the terms of the contractual arrangements. Payments under some of these contracts depend on research and non-clinical trial milestones. There may be instances in which payments made to the Company’s vendors will exceed the level of services provided and result in a prepayment of expenses. In accruing service fees, the Company estimates the period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual or prepaid expense accordingly. The Company has not experienced any material differences between accrued costs and actual costs incurred since its inception.

Convertible Preferred Stock

As the Convertible Preferred Stockholders have liquidation rights in the event of a deemed liquidation event that, in certain situations, are not solely within the control of the Company and would require the redemption of the then-outstanding Convertible Preferred Stock, the Company classifies the Convertible Preferred Stock in mezzanine equity on the balance sheet. Due to the fact that

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the occurrence of a deemed liquidation event is not currently probable, the carrying value of the Convertible Preferred Stock is not being accreted to its redemption value. Subsequent adjustments to the carrying value of the Convertible Preferred Stock would be made only when a deemed liquidation event becomes probable.

Stock-Based Compensation

The Company accounts for its stock-based compensation awards in accordance with ASC Topic 718, Compensation—Stock Compensation (“ASC 718”). ASC 718 requires all stock-based payments to employees and non-employees to be recognized based on their fair value on the date of the grant. The Company estimates the grant date fair value using the Black-Scholes option pricing model, which requires the input of subjective assumptions, including (i) the expected stock price volatility, (ii) the calculation of expected term of the award, (iii) the risk-free interest rate and (iv) expected dividends. Due to the lack of complete company-specific historical and implied volatility data for the full expected term of the stock-based awards, the Company bases its estimate of expected volatility on a representative group of publicly traded companies. The expected term assumption for employee grants is determined by using the “simplified” method for awards that qualify as “plain-vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. The risk-free interest rate is based on the rate of the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends on common stock and does not expect to pay any cash dividends in the foreseeable future. Forfeitures are accounted for as they occur.

The Company classifies stock-based compensation expense in the statement of operations in the same manner in which the award recipients’ payroll costs are classified or the award recipients’ service payments are classified. The Company accounts for awards granted to non-employees using the same treatment as awards granted to employees.

Upon exercise of stock options, the Company issues the grantee the respective number of shares of common stock from the available common stock shares approved for issuance by the Board of Directors. Until the restricted stock awards vest, the Company can repurchase unvested awards for a period of up to 90 days following termination. The Company is also entitled to repurchase early exercised unvested stock options. The Company records a liability on the balance sheet for any early exercised stock options awards. As of December 31, 2021, the Company recorded a $397,430 share repurchase liability on the balance sheet for the early exercise of unvested stock options and unvested shares of restricted stock subject to repurchase.

Income Taxes

The Company accounts for income taxes in accordance with FASB ASC 740, Income Taxes (“ASC 740”). ASC 740 requires the use of the asset and liability method of accounting for income taxes. The current or deferred tax consequences of a transaction are measured by applying the provisions of enacted tax laws to determine the amount of taxes payable currently or in future years. Deferred tax assets and liabilities are determined based on the difference between the financial statements and tax basis of assets and liabilities and expected future tax consequences of events that have been included in the financial statements or tax returns using enacted tax rates in effect for the year in which the differences are expected to reverse. Under this method, a valuation allowance is used to offset deferred tax assets if, based upon the available evidence, it is more likely than not that some or all of the deferred tax assets may not be realized. Management annually evaluates the recoverability of deferred taxes and the adequacy of the valuation allowance as further discussed in Note 12, “Income Taxes.”

The Company follows the provisions of ASC 740 relative to accounting for uncertain tax positions. These provisions provide guidance on the recognition, de-recognition, and measurement of potential tax benefits associated with tax positions.

Derivative Liability

The Company does not use derivative instruments to hedge exposures to cash flow, market or foreign currency risks. The Company evaluates all of its financial instruments, to determine if such instruments are derivatives or contain features that qualify as embedded derivatives. In connection with certain transactions, the Company has identified certain embedded derivatives that requires separate accounting, which are recorded as liabilities on the Company’s balance sheet and are remeasured to fair value at each reporting date until the derivative is settled. Changes in the fair value of the derivative liabilities are recognized as other income (expense) in the statement of operations.

Fair Value Measurements

In determining the fair value of its assets and liabilities, the Company uses various valuation approaches. The Company employs a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy is broken down into three levels based on the source of inputs as follows:

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The availability of observable inputs can vary among the various types of financial assets and liabilities. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for financial statement disclosure purposes, the level in the fair value hierarchy within which the fair value measurement is categorized is based on the lowest level input that is significant to the overall fair value measurement.

Commitments and Contingencies

Legal Proceedings

From time to time, the Company may become involved in litigation, inquiries and/or investigation relating to claims arising from the ordinary course of business. As of December 31, 2021 and 2020, there are no claims or actions pending against the Company, the ultimate disposition of which would have a material adverse effect on the Company’s results of operations, financial condition or cash flows. Management updates its assessment each reporting period and updates amounts accrued and disclosed accordingly.

Guarantees and Indemnifications

The Company’s certificate of incorporation requires the Company to indemnify and advance expenses to its officers and directors and agents to the fullest extent permitted by law. Under the Company’s operating lease terms, the Company is required to indemnify the lessor against claims, actions, or damages incurred in connection with, among other items, the Company’s occupancy, and use of the premises. The Company’s equity agreements and certain other arrangements include standard indemnifications against claims, actions, or other matters that may arise in connection with these arrangements.

As of December 31, 2021, and 2020, the Company had not experienced any losses related to these indemnification obligations, and no claims with respect thereto were outstanding. The Company does not expect significant claims related to these indemnification obligations and has no amount accrued related to these contingencies.

Recently Issued Accounting Pronouncements – Not Yet Adopted

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its financial statements and disclosures.

ASU No. 2016-02, Leases (Topic 842)

In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). Under this accounting standard (and various amendments to ASU 2016-02 issued by the FASB, collectively referred to as “ASC 842”), lessees are required to recognize a right-of-use asset and a lease liability for virtually all of their leases (other than leases that meet the definition of a short-term lease). The liability is equal to the present value of lease payments. The asset is based on the liability, subject to certain adjustments, such as for initial direct costs. For income statement purposes, a dual model was retained, requiring leases to be classified as either operating or finance leases. Operating leases result in straight line expense (similar to operating leases under the prior accounting standard), while finance leases result in a frontloaded expense pattern (similar to capital leases under the prior accounting standard). Lessor accounting is similar to the prior model but updated to align with certain changes to the lessee model (e.g., certain definitions, such as initial direct costs, have been updated) and the new revenue recognition standard. ASC 842 is effective for the Company beginning January 1, 2022. The Company is currently evaluating the potential impact this standard may have on its financial statements upon adoption.

ASU No. 2019-12, Income Taxes (Topic 740)

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. This standard simplifies the accounting for income taxes through the removal of various exceptions previously provided, as well providing additional reporting requirements for income taxes. The ASU is effective for the Company on January 1, 2022. The Company is currently evaluating the potential impact this standard may have on its financial statements upon adoption.

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ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40)

In August 2020, the FASB issued ASU 2020-06, which simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity’s own equity. This standard will be effective for the Company on January 1, 2024, with early adoption permitted (but no earlier than fiscal years beginning after December 15, 2020). The Company is currently evaluating the potential impact this standard may have on its financial statements upon adoption.

3.    Fair Value Measurements

Fair Value Measured on a Recurring Basis

Financial liabilities measured at fair value on a recurring basis consist of the following as of December 31, 2021 and 2020:

Derivative Liability

In connection with license agreements entered into with a university and a third party as further described in Note 7, the Company recorded a derivative liability on its balance sheet associated with a fee due to the licensors upon an event of change of control. The Company remeasures the derivative liability at fair value at each reporting date and recognizes changes in the fair value of the derivative liability as a component of other income (expense) in the statement of operations. The university is a related party which is further described in Note 13.

Management determined the fair value of the derivative liability using a Monte Carlo simulation analysis with assumptions for volatility, cost of debt, and time to liquidity. The inputs used to calculate the fair value of the derivative liability are considered to be Level 3 inputs due to the lack of relevant market activity and significant management judgment.

The significant assumptions used in valuing the derivatives in the Monte Carlo simulation model are as follows:

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A reconciliation of the change in fair value of derivative liability is included in the following table:

The fair value of the derivative liability is based on the expected value of the consideration to be delivered, discounted to present value. The actual value to be delivered upon settlement of the derivatives may differ materially from current estimates. Reasonable changes in assumptions could materially affect the estimated fair value of the derivative liability.

Fair Value Measured on a Nonrecurring Basis

During the years ended December 31, 2021 and 2020, there were no re-measurements to fair value of financial assets and liabilities that are measured at fair value on a nonrecurring basis.

4.    Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following:

5.    Property and Equipment, Net

Property and equipment, net, consisted of the following:

Depreciation expense for the years ended December 31, 2021 and December 31, 2020 was $424,536 and $88,822 respectively.

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6.    Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following:

7.    License Agreements

License Agreements with a University

Between March 2020 and June 2021, the Company entered into multiple license agreements with a university, a related party as further described in Note 13, Related Party Transactions, relating to certain patent rights and know how. Under the license, the Company is obligated to use commercially reasonable efforts to develop, commercialize and maintain supply of licensed product.

In connection with the license, the Company paid an aggregate upfront fee of $45,000 and issued 268,529 shares of common stock with a fair value of $0.0079/share to the university. Under the terms of the license, the Company is required to pay an aggregate annual license maintenance fee of $45,000 until the first year in which the Company sells a licensed product. The Company also agreed to pay royalties on annual net sales of licensed products on a licensed-product-by-licensed product basis until the expiration of the last of the patent rights licensed under the license. In addition, the Company is required to make contingent milestone payments to the university totaling up to $15.4 million aggregate upon the achievement of certain clinical and regulatory milestones. In the event that the Company sublicenses the licensed patent rights, the university is also entitled to receive a percentage of the sublicensing revenue received by the Company. Lastly, the Company is required to pay a fee not to exceed $10.0 million in aggregate upon a change in control as discussed further in Note 3, Fair Value Measurements.

In addition to the license agreements, the Company entered three option agreements with the university, pursuant to which the Company obtained an exclusive option to obtain a royalty-bearing, limited-term, worldwide, exclusive license under certain Patent Rights relating to (i) the field of Methods of packaging multiple Adeno Associated Virus vectors, (ii) the field of Adeno-Associated Virus Vectors for Treatment of Glycogen Storage Disease and (iii) the field of management of immunity against AAV-mediated gene therapy. The Company exercised its rights under each option agreement in March 2021 and executed standard exclusive or non-exclusive license agreements, accordingly.

All payments made and the shares of common stock issued to the university have been expensed as research and development expenses in the statements of operations. The financial statements as of December 31, 2021 and 2020 include a liability with respect to the first milestone payment of $50,000 that will be paid during the year ending December 31, 2022. The Company has recorded a derivative liability associated with the payment due upon a change in control, as discussed in Note 3.

License Agreement with a Third Party

In December 2020, the Company entered into a non-exclusive license agreement with a third party with respect to life cells for producing genetically engineered adeno associated virus (AAV) particles.

In connection with the license, the Company paid an upfront fee of $450,000. In addition, the Company is required to pay a fee of $450,000 for each additional licensee product added to the license and a fee of $50,000 for each additional cell line documentation package. Lastly, the Company is required to pay a fee of $450,000 upon a change in control. The Company has recorded a derivative liability associated with the payment due upon a change in control.

All payments made to the third party have been expensed as research and development expenses in the statements of operations. The financial statements as of December 31, 2021 and 2020 do not include any liabilities with respect to the third party as the Company has not yet generated revenue and the achievement of certain milestones is not probable.

License Agreement with Another University

In December 2021, the Company entered into an exclusive license agreement with another university with respect to certain patent rights.

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In connection with the license, the Company paid an upfront fee of $20,000. In addition, under the terms of the license, the Company is required to pay a minimum annual license maintenance fee of $10,000 for years 2022-2025 and $25,000 for year 2026 and thereafter, until the first year in which the Company sells a licensed product. The Company also agreed to pay royalties on annual net sales of licensed products on a licensed-product-by-licensed product until the expiration of the last of the patent rights licensed under the license. In addition, the Company is required to make contingent milestone payments totaling up to $5.0 million in aggregate upon the achievement of certain clinical and regulatory milestones. In the event that the Company sublicenses the licensed patent rights, the university is also entitled to receive a percentage of the sublicensing revenue received by the Company. The Company is required to pay ongoing patent expense fees in relation to the licensed patents.

All payments made to the university have been expensed as research and development expenses in the statement of operations. The financial statements as of December 31, 2021 and 2020 do not include any liabilities with respect to the license as the Company has not yet generated revenue and the achievement of certain milestones is not probable.

Convertible promissory notes

On October 17, 2019, the Company entered into an agreement to sell $1.5 million of convertible promissory notes (“2019 Note Purchase Agreement”). The notes carried an interest rate of 8% and were convertible into a subsequent financing or repaid at the holders’ option.

On June 19, 2020, the Company entered into an agreement to sell $9.0 million of convertible notes to new investors (“2020 Note Purchase Agreement”). The notes carried an interest rate of 6% and were convertible into a subsequent financing or repaid at the holders’ option.

Upon the closing of the Series A-1 convertible preferred stock financing in October and November 2020, the convertible promissory notes and the related accrued interest of $295,000 were converted into shares of Series A-1 Convertible Preferred Stock. The Company elected the fair value option under ASC 825 Financial Instruments to account for the convertible promissory notes and there was no gain or loss recorded upon the conversion to Series A-1 Convertible Preferred Stock.

Series A Convertible Preferred Stock

In October 2020, the Company entered into a securities purchase agreement (“Series A Agreement”) with certain investors to sell up 19,498,328 Series A Convertible Preferred Stock which included 9,028,486 shares of Series A-1 at $4.8321 per share and 10,469,842 shares of Series A-2 at $6.0401 per share. The Series A Agreement contemplated an initial closing which occurred in October 2020 and an interim closing (“Interim Closing”), which occurred in November 2020. The Series A Agreement also contemplated two tranche closings, for Convertible Preferred Stock to be purchased at a stated price per share, contingent upon certain closing conditions, unless waived by the holders of 67% of the outstanding shares of Convertible Preferred Stock (the “Requisite Holders”).

In October 2020, the initial closing, the Company issued 6,741,915 shares of Series A-1 Convertible Preferred Stock at $4.8321 (“Series A-1 Original Issue Price”) per share for gross cash proceeds of $32.6 million less issuance costs of $313,000, resulting in net proceeds of $32.3 million. In addition, the Company issued 1,900,507 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share in consideration of the cancellation of the notes issued under the 2020 Note Purchase Agreement of $9.2 million.

In November 2020, the Company issued 51,737 shares of Series A-1 Convertible Preferred Stock at a price of $4.8321 per share for gross cash proceeds of $250,000. In addition, the Company issued 334,327 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share in consideration of the cancellation of notes issued under the 2019 Note Purchase Agreement of $1.6 million.

On June 25, 2021, the Series A Agreement was amended to: (i) add an additional purchaser for purposes of the Second Tranche closing initially outlined in the Series A Agreement and (ii) provide that the shares issued at the Second Tranche closing will be shares of Series A-1 instead of Series A-2 and will be issued at an Original Issue Price per share of $4.8321, as well as increased the authorized issuance of the Series A Convertible Preferred Stock to 21,023,162 shares, which included 15,788,241 shares of Series A-1 at $4.8321 per share and 5,234,921 shares of Series A-2 at $6.0401 per share.

On July 1, 2021, the Company obtained approval from the Requisite Holders to waive the conditions to the Second Tranche closing and closed the Second Tranche of the Series A Convertible Preferred Stock financing. At the Second Tranche closing, the Company issued 6,759,754 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share for gross cash proceeds of $32.6 million, less issuance costs of $78,000, as well as payment in service of $44,373, resulting in net proceeds of $32.5 million. An investor elected not to participate in the Second Tranche closing, resulting in 1,055,441 shares of Convertible Preferred Stock automatically converting into common stock at $4.8321 per share, or $5.1 million, in accordance with the Amended and Restated Certificate of Incorporation (“ARCOI”).

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The rights, preferences, and privileges of the holders of Convertible Preferred Stock under the ARCOI following the issuance of Series A are as follows:

Voting Rights

The holders of each share of Convertible Preferred Stock have the right to one vote for each share of common stock into which such Convertible Preferred Stock could then be converted, and with respect to such vote, such holder shall have full voting rights and powers equal to the voting rights and powers of the holders of common stock.

Dividends

The holders of then outstanding shares of Convertible Preferred Stock are entitled to receive dividends, out of any assets legally available; prior and in preference to any declaration or payment of any dividend on the common stock by the Company at a rate of 8% of the applicable Original Issuance Price (as defined above) per annum, payable when, as and if declared by the Company’s Board of Directors (the “Board”). Such dividends are not cumulative and no right to dividends shall accrue to holders of the Convertible Preferred Stock by reason of the fact that dividends on said shares are not declared. After payment of such dividends, any additional dividends or distributions shall be distributed among all holders of common stock and Convertible Preferred Stock in proportion to the number of shares of common stock that each such holder would hold if all shares of Convertible Preferred Stock were converted to common stock at the then effective conversion rate.

Liquidation

In the event of any voluntary or involuntary liquidation, dissolution, winding up of the Company or deemed liquidation event (as defined in the ARCOI, the holders of shares of Convertible Preferred Stock then outstanding shall be entitled to be paid out of the assets of the Company available for distribution to its stockholders before any payment shall be made to the holders of the common stock, an amount per share equal to the greater of (I) 1.5x the applicable Original Issue Price, plus any dividends declared but unpaid or (II) such amount per share as would have been payable had all shares of Convertible Preferred Stock been converted into common stock immediately prior to such liquidation, dissolution, winding up or deemed liquidation event. If upon any such liquidation, dissolution or winding up of the Company or deemed liquidation event, the assets of the Company available for distribution to its stockholders shall be insufficient to pay the holders of shares of Convertible Preferred Stock the full amount to which they shall be entitled, the holders of shares of Convertible Preferred Stock shall share ratably in any distribution of the assets available for distribution in proportion to the respective amounts which would otherwise be payable in respect of the shares held by them upon such distribution if all amounts payable on or with respect to such shares were paid in full.

Conversion

Each share of Convertible Preferred Stock shall be convertible, at the option of the holder, at any time and from time to time, into such number of fully paid and non-assessable share of common stock as is determined by dividing the applicable Original Issue Price by the Applicable Conversion Price (as defined in the ARCOI) in effect at the time of conversion, which is initially equal to the Original Issue Price. In the event of a liquidation, dissolution, winding up of the Company or a deemed liquidation event, the conversion rights shall terminate at the close of business on the last full day preceding the date fixed for payment of any such amounts distributable on such event to the holders of Convertible Preferred Stock.

Upon either (a) the closing of the sale of shares of common stock to the public at a price of at least $12.0802 per share, in a firm commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $50.0 million of gross proceeds, net of the underwriting discount and commissions, to the Company and in connection with such offering the common stock is listed for trading, (b) the Company’s completion of a merger or consolidation with a special purpose acquisition company or its subsidiary in which the common stock of the surviving parent are listed in which the initial price per share of the Company following such merger is at least $12.0802 and in connection with which the surviving or parent entity receives gross proceeds of at least $50.0 million from the sale of its equity securities, or (c) the date and time, or the occurrence of an event, specified by vote or written consent of the Requisite Holders then (‘i) all outstanding share of Convertible Preferred Stock shall automatically be converted into share of common stock at the then effective conversion rate and (‘ii) such share may not be reissued by the Company.

Redemption

The Convertible Preferred Stock is not redeemable at the option of the stockholders and is only redeemable upon a Deemed Liquidation Event. As such, the Convertible Preferred Stock is considered contingently redeemable at the option of the holders rather than mandatorily redeemable because the holders may never elect to redeem the Convertible Preferred Stock and the Convertible Preferred Stock may or may not be redeemed in the event of a Deemed Liquidation Event. Any shares of Convertible Preferred Stock that are redeemed or otherwise acquired by the Company shall be automatically and immediately cancelled and retired and shall not be reissued, sold or transferred.

The features associated with the Series A-1 and Series A-2 Convertible Preferred Stock were evaluated in accordance with ASC 815. It was determined that none of the features within the Series A-1 and Series A-2 Convertible Preferred Stock were required to be bifurcated from the host instrument. The Company also concluded that no beneficial conversion features existed on the issuance dates.

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The Company is authorized to issue up to 36,000,000 shares of common stock, of which 5,402,848 shares were issued and outstanding at December 31, 2021.

The holders of the Company’s common stock are entitled to one vote for each share of common stock held, subject to certain limitations pertaining to the Convertible Preferred Stock. Common stockholders are entitled to receive dividends, as may be declared by the Board of Directors, subject to the preferential dividend rights of Convertible Preferred Stock. No dividends were declared or paid during the year ended December 31, 2021. In the event of any voluntary or involuntary liquidation, dissolution, winding up of the Company or deemed liquidation event, the holders of shares of common stock then outstanding shall be entitled to be paid out of the assets of the Company available for distribution to its stockholders after payment shall be made to the holders of the Convertible Preferred Stock.

The Company has reserved shares of common stock for the conversion or exercise of the following securities:

Equity incentive plan

In 2019, the Company’s Board of Directors adopted the 2019 Equity Incentive Plan (the “2019 Plan”), under which the Company may grant options and restricted stock to its employees and certain non-employees. The 2019 Plan was amended in July 2021, with the issuance of the Second Tranche closing, to increase the number of shares of common stock authorized and reserved for issuance under the 2019 Plan from 3,103,085 shares to 5,006,242 shares.

The Company may grant options to purchase authorized but unissued shares of the Company’s common stock. Options granted under the 2019 Plan include incentive stock options that can be granted only to the Company’s employees and non-statutory stock options that can be granted to the Company’s employees, consultants, advisors, and directors. The 2019 Plan also permits the Company to issue restricted stock awards.

Option awards are generally granted with an exercise price equal to the fair value of the Company’s common stock at the date of grant. No grant may have a term in excess of ten years. Options granted under the 2019 Plan are exercisable in whole or in part at any time subsequent to vesting.

Stock Options

The following table summarizes the Company’s stock option activity during the period:

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The fair value of each option is estimated on the date of grant using the Black-Scholes option pricing model using the assumptions noted in the table below. The grant date fair value is recorded as compensation cost on a straight-line basis over the requisite service period of the awards, which is generally the vesting period.

The Company used the following assumptions when valuing share-based payments:

A total fair value of options vested during the year ended December 31, 2021 was $292,518. The weighted-average grant-date fair value of the stock options granted during the year ended December 31, 2021 was $1.05. For the year ended December 31, 2021, stock-based compensation expense related to stock options was $641,311. The total intrinsic value of stock options exercised during the year ended December 31, 2021 was $0.58.

As of December 31, 2021, the total unrecognized compensation cost related to non-vested stock options was $2.5 million that is expected to be recognized over a weighted-average period of 3 years.

The following table summarizes total stock compensation by department during the period:

Restricted stock

A summary of the Company’s non-vested restricted common stock shares as of December 31, 2021, and changes during the year then ended is presented below:

These unvested shares are subject to a repurchase feature through the vesting period, and therefore are issued but not outstanding until they vest.

Operating Leases

On December 12, 2019, the Company entered into an operating lease which commenced on May 1, 2020, for office and laboratory space in Florida, which expires in April of 2025. The Company has the right to extend the lease for two additional five-year periods at a market rate as determined by the landlord and agreed to by the Company. As part of the operating lease agreement, the Company received a tenant improvement allowance of $343,700 which is recorded as a leasehold improvement within property and equipment, net and lease incentive liability, in other current and other long-term liabilities on the balance sheet as of December 31, 2021 and 2020. The lease incentive liability is recognized as a reduction of rent expense on a straight-line basis over the term of the lease in accordance with ASC 840. Rent expense for the years ended December 31, 2021 and 2020 was $192,472 and $128,314, respectively.

17

On January 1, 2021, the Company entered into an additional operating lease for office and laboratory space in Florida, which expires in December 2022. The Company has the right to extend the lease for an additional twelve-month period at a market rate as determined by the landlord and agreed to by the Company. Rent expense for the year ended December 31, 2021 was $214,572.

On August 1, 2021, the Company entered into another operating lease for laboratory space in Florida, which expires in December 2022. The Company has the right to extend the lease for three additional one-year periods at a market rental rate as determined by the landlord and agreed to by the Company. Rent expense for the year ended December 31, 2021 was $21,850.

The Company’s aggregate minimum lease obligations for the years ending December 31, are as follows:

On January 10, 2022, the Company entered an operating lease which commenced on April 4, 2022, for office and laboratory space in Florida that expires in October 2032 and has total lease payments of $3.9 million over the lease term. The Company has the right to extend the lease for two additional five-year periods at a market rate as determined by the landlord and agreed to by the Company.

On January 17, 2022, the Company entered into an operating lease which commenced on February 16, 2022, for office and laboratory space in North Carolina through February 2024, with total lease payments of $430,500 over the lease term. The Company has the right to extend the lease for one additional two-year period at a market rate as determined by the landlord and agreed to by the Company.

Employee Benefit Plan

In January 2021, the Company implemented a 401K Plan which covers all eligible employees of the Company (the “401K Plan”). Employer matching contributions are immediately 100% vested. The Company’s 401K Plan provides that the Company match each participant’s contribution at 100% up to 6% of the employee’s eligible compensation. Company contributions to the 401K Plan totaled approximately $161,680 and $0 for the years ended December 31, 2021 and 2020, respectively.

During the years ended December 31, 2021 and 2020, the Company recorded no income tax benefits for the net operating losses incurred in the year due to its uncertainty of realizing a benefit from those items. All of the Company’s losses before income taxes were generated in the United States.

A reconciliation of income taxes computed using the U.S. federal statutory rate to that reflected in operations as of December 31, 2021 and 2020 is as follows:

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Net deferred tax assets as of December 31, 2021 and 2020 consisted of the following (in thousands):

As of December 31, 2021, the Company had federal and state net operating loss carryforwards of $11.5 million and $7.3 million respectively. The Company’s federal NOLs generated for the years ended after December 31, 2018 can be carried forward indefinitely. The Company’s state NOLs which may be available to reduce future taxable income and expire at various dates beginning in 2032. In addition, the Company had federal and state research and development tax credit carryforwards of $512,520 and $20,487, available to reduce future tax liabilities which start to expire at various dates beginning in 2042 and 2037, respectively.

Utilization of the U.S. NOL carryforwards and credits may be subject to annual limitations due to the ownership percentage change limitations provided by Internal Revenue Code Section 382 and similar state provisions. In the event of a deemed change in control under Internal Revenue Code Section 382, an annual limitation on the utilization of NOL and credits may result in the expiration of all or a portion of the NOL and credit carryforwards. The Company has not, as yet, conducted a study to determine if any such changes have occurred that could limit its ability to use the NOL and tax credit carryforwards.

In accordance with Statement of ASC 740, management of the Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets, which are comprised principally of amortization and net operating loss carryforwards. Management has determined that it is more likely than not that the Company will not recognize the benefits of federal and state deferred tax assets and, as a result, a full valuation allowance of $10.6 million and $1.8 million has been established at December 31, 2021 and December 31, 2020, respectively.

19

The Company has assessed its uncertain tax positions according to the guidance outlined in ASC 740. As of December 31, 2021 and December 31, 2020, there are no tax matters under discussion with taxing authorities. As such, the Company has not recorded any tax reserves. However, the Statute of Limitations is open for the tax years ended December 31, 2020, 2019, 2018 and 2017.

The Company has not yet conducted a study of its research and development credit carryforwards. This study may result in an increase or decrease to the Company’s credit carryforwards; however, until a study is completed, and any adjustment is known, no amounts are being presented as an uncertain tax position. A full valuation allowance has been provided against the Company’s credits, and if an adjustment is required, this adjustment would be offset by an adjustment to the valuation allowance. As a result, there would be no impact to the statements of operations and comprehensive loss or statements of cash flows if an adjustment were required.

The Company has a related party relationship with a university and a research foundation. The research foundation is a separate corporation that manages intellectual property that arises from the research activities of the university faculty and staff. The Company’s two Founders, who also serve on the Board of Directors of the Company, are employed by the university, own 5,000,000 shares of the Company’s common stock and are compensated as consultants. The Founders were both paid $100,000 in 2021 and $50,000 and $61,360, respectively, in 2020. These amounts were recorded on the statements of operations for the years ended December 31, 2021 and 2020, accordingly.

As discussed in Note 7, License Agreements, the Company has entered into multiple licensing agreements with the university and research foundation and recorded $1,850,000 and $460,000 of research and development expense in the statements of operations for the years ended December 31, 2021 and 2020, accordingly. Additionally, the financial statements as of December 31, 2021 and 2020 include a liability with respect to the first milestone payment of $50,000 related to the license that will be paid during the year ending December 31, 2022.

The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. The Company is not aware of any material subsequent events other than those disclosed below:

Series A Financing

On February 24, 2022, the Company and the Requisite Holders entered into the second amendment to the Series A Agreement to increase the authorized issuance of the Series A Convertible Preferred Stock to 27,900,000 shares, which included 14,732,800 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share and 13,087,248 shares of Series A-2 Convertible Preferred Stock at $2.4161 per share. Concurrently, on February 24, 2022, the Company obtained approval from the Requisite Holders to waive the conditions to the Third Tranche closing, and closed the Third Tranche of the Series A Convertible Preferred Stock financing. At the Third Tranche closing, the Company issued 13,087,248 shares of Series A-2 Convertible Preferred Stock at $2.4161 per share for gross cash proceeds of $31.6 million.

2019 Plan

The 2019 Plan was amended in February 2022, with the issuance of the Third Tranche closing, to increase the number of shares of common stock authorized and reserved for issuance under the 2019 Plan from 5,006,242 shares to 8,688,053.

Restructuring

On June 27, 2022, the Company announced a restructuring (the “Restructuring”) to extend its cash runway while furthering the development of its pipeline. The Restructuring was made in connection with a challenging economic environment and changes to the Company’s Friedreich’s ataxia program. As part of the Restructuring, the Company reduced its workforce by 47%, or 33 full-time employees, resulting in restructuring charges of approximately $0.3 million. The reduction in force was completed by the end of July 2022.

Operating Leases

The Company entered into two new leases on January 10 and January 17, 2022, respectively. The leases are further described in Note 11.

On October 21, 2022, the Company terminated the lease agreement with Laser Investment Group, LLC that was executed on January 10, 2022, as discussed in Note 11. The Company paid a $2.0 million termination fee to relieve all of its remaining obligations under the lease.

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Merger Agreement

On September 29, 2022, Solid Biosciences Inc. and the Company entered into an Agreement and Plan of Merger. The Merger Agreement provides for the acquisition of the Company, with the Company surviving as a wholly owned subsidiary of Solid Biosciences Inc.

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Exhibit 99.3

INDEX TO CONDENSED FINANCIAL STATEMENTS

1

AavantiBio, Inc.

Condensed Balance Sheets

(in thousands, except share and per share amounts)

(Unaudited)

See accompanying notes to condensed financial statements (Unaudited).

2

AavantiBio, Inc.

Condensed Statements of Operations and Comprehensive Loss

(in thousands)

(Unaudited)

See accompanying notes to the condensed financial statements (Unaudited).

3

AavantiBio, Inc.

Condensed Statements of Convertible Preferred Stock and Stockholders’ Deficit

(in thousands, except share amounts)

(Unaudited)

See accompanying notes to the condensed financial statements (Unaudited).

4

AavantiBio, Inc.

Condensed Statements of Cash Flows

(in thousands)

(Unaudited)

See accompanying notes to the condensed financial statements (Unaudited).

5

AavantiBio, Inc.

Notes to Condensed Financial Statements

(Unaudited)

AavantiBio, Inc. (“AavantiBio” or the “Company”) is a gene therapy company focused on transforming the lives of patients with rare genetic diseases. The Company was incorporated on August 14, 2019, under the laws of the state of Delaware, and its principal offices are in Cambridge, Massachusetts.

The Company is subject to risks and uncertainties common to early-stage companies in the biopharmaceutical industry, including, but not limited to, risks related to the successful development and commercialization of product candidates, fluctuations in operating results and financial risks, the ability to successfully raise additional funds when needed, protection of proprietary rights and patent risks, patent litigation, compliance with government regulations, dependence on key personnel and prospective collaborative partners, and competition from competing products in the marketplace.

Liquidity

As of September 30, 2022, the Company had an accumulated deficit of $75.5 million. The Company has incurred losses and negative cash flows from operations since inception, including net losses of $31.3 million and $24.8 million for the nine months ended September 30, 2022 and 2021, respectively, and the Company expects that its operating losses and negative cash flows will continue for the foreseeable future as the Company continues its research and development (R&D) programs and develops its product candidates.

The Company expects that its cash on hand of $37.6 million as of September 30, 2022, will fund the Company’s operations through at least one year from the date of issuance of these condensed financial statements.

Management also may, in the future, seek to raise additional funds through equity or debt financings or through collaboration transactions. The Company may be unable to obtain equity or debt financings or to enter into collaboration transactions and, if necessary, the Company will be required to implement cost reduction strategies. The condensed 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 might result from the outcome of this uncertainty.

Agreement and Plan of Merger

On September 29, 2022, Solid Biosciences Inc. (“Solid”) and the Company entered into an Agreement and Plan of Merger, which provides for the acquisition of the Company, with the Company surviving as a wholly owned subsidiary of Solid Biosciences Inc.

Basis of Presentation

The accompanying condensed financial statements are presented in accordance with accounting standards generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

The Company’s significant accounting policies are disclosed in Note 2, “Summary of Significant Accounting Policies,” in the audited financial statements for the year ended December 31, 2021, and notes thereto, included in Exhibit 99.2 of this Solid Current Report on Form 8-K filed with the Securities and Exchange Commission on December 5, 2022 (the “Solid Form 8-K”) of which this Exhibit 99.3 is a part. Since the date of those financial statements, there have been no changes to significant accounting policies, except as noted below for leases.

Unaudited Interim Financial Information

The accompanying condensed interim financial statements are unaudited. The unaudited condensed interim financial statements have been prepared on the same basis as the audited annual financial statements except for the adoption of ASU No. 2016-02, Leases (Topic 842), as discussed further in this Note 2, “Summary of Significant Accounting Policies” and in Note 11, “Commitments and Contingencies.” In the opinion of management, the accompanying unaudited interim condensed financial statements reflect all adjustments, which include only normal recurring adjustments, necessary for the fair presentation of the Company’s condensed financial position as of September 30, 2022, the Company’s condensed results of its operations for the nine months ended September 30, 2022 and 2021, and the Company’s cash flows for the nine months ended September 30, 2022 and 2021. The condensed financial data and other information disclosed in these notes related to nine months ended September 30, 2022 and 2021 are unaudited. The condensed results for the nine months ended September 30, 2022 are not necessarily indicative of results to be expected for the year ending December 31, 2022, any other interim periods, or any future year or period.

6

Recently Adopted Accounting Pronouncements

ASU No. 2016-02, Leases (Topic 842)

The Company adopted ASU No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), as of January 1, 2022 using the modified retrospective transition approach. With the adoption, there was no restatement of prior periods or cumulative adjustment to accumulated deficit. As a result, prior periods are presented in accordance with the previous guidance in ASC 840, Leases (“ASC 840”). Upon adoption, the Company elected the package of transition practical expedients, which allowed the Company to carry forward prior conclusions related to whether any expired or existing contracts are or contain leases, the lease classification for any expired or existing leases and initial direct costs for existing leases. The Company also made an accounting policy election not to recognize leases with an initial term of 12 months or less within its balance sheets and to recognize those lease payments on a straight-line basis in its statements of operations over the lease term. The Company elected the practical expedient to not separate lease and non-lease components for its leases.

The Company evaluates whether an arrangement is or contains a lease at the inception date. If determined to be or contain a lease, the Company determines the classification of the lease at the commencement date, which represents the date at which the lessor makes the underlying asset available for use by the Company. When determining the expected accounting lease term, the Company includes the noncancellable lease term, together with periods covered by (i) an option to extend the lease if the Company is reasonably certain to exercise such option, (ii) an option to terminate the lease if the Company is reasonably certain not to exercise such option and (iii) an option to extend or not terminate the lease where the exercise of such option is controlled by the lessor.

Operating lease right-of-use assets represent the Company’s right to use an underlying asset over the lease term and operating lease liabilities represent the Company’s obligation to make lease payments under the arrangement. The Company measures its operating lease liabilities as the present value of the lease payments, discounted using an incremental borrowing rate, as interest rates implicit in lease arrangements are generally not readily determinable. The Company measures its right-of-use assets as the present value of its lease payments at the commencement date. The incremental borrowing rate represents the interest rate at which the Company could borrow an amount equal to the lease payments on a fully collateralized basis, over a similar term, in a similar economic environment. The Company recognizes rent expense for operating leases on a straight-line basis. The Company recognizes variable lease expenses as incurred.

The Company remeasures operating lease right-of-use assets and operating lease liabilities when a lease is modified, and the modification is not accounted for as a separate contract. A modification is accounted for as a separate contract if the modification grants the Company an additional right of use not included in the original lease arrangement and the increase in lease payments is commensurate with the additional right of use. The Company assesses its right-of-use assets for impairment in a manner consistent with its assessment for long-lived assets held and used in operations.

Upon adoption of ASU 2016-02, the Company recognized operating lease right-of-use assets of approximately $1.4 million and a corresponding operating lease liability of approximately $1.4 million, which are included in the Company’s condensed balance sheet. The adoption of ASU 2016-02 did not have any impact on the Company’s statements of operations and comprehensive loss.

ASU No. 2019-12, Income Taxes (Topic 740)

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. This standard simplifies the accounting for income taxes through the removal of various exceptions previously provided, as well providing additional reporting requirements for income taxes. The Company adopted this ASU on January 1, 2022. The adoption of this new standard did not have a material impact on the Company’s condensed financial statements.

Recently Issued Accounting Pronouncements – Not Yet Adopted

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its financial statements and disclosures.

ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40)

In August 2020, the FASB issued ASU 2020-06, which simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity’s own equity. This standard will be effective for the Company on January 1, 2024, with early adoption permitted (but no earlier than fiscal years beginning after December 15, 2020). The Company is currently evaluating the potential impact this standard may have on its financial statements upon adoption.

7

Fair Value Measured on a Recurring Basis

Financial liabilities measured at fair value on a recurring basis consist of the following as of September 30, 2022 and December 31, 2021:

Derivative Liability

In connection with license agreements entered into with a university and a third party as further described in Note 7, “License Agreements,” in the audited financial statements for the year ended December 31, 2021, and notes thereto, included in the Solid Form 8-K, the Company recorded a derivative liability on its balance sheet associated with a fee due to the licensors upon an event of change of control. The Company remeasures the derivative liability at fair value at each reporting date and recognizes changes in the fair value of the derivative liability as a component of other income (expense) in the condensed statement of operations and comprehensive loss. The university is a related party which is further described in Note 13.

Management determined the fair value of the derivative liability using a Monte Carlo simulation analysis with assumptions for expected volatility, discount rate, and time to liquidity. The inputs used to calculate the fair value of the derivative liability are considered to be Level 3 inputs due to the lack of relevant market activity and significant management judgment.

The significant assumptions used in valuing the derivative liability in the Monte Carlo simulation model are as follows:

The reconciliation of changes in the fair value of the derivative liability based on Level 3 inputs for the nine months ended September 30, 2022 is as follows:

The reconciliation of changes in the fair value of the derivative liability based on Level 3 inputs for the nine months ended September 30, 2021 is as follows:

The fair value of the derivative liability is based on the expected value of the consideration to be delivered, discounted to present value. The actual value to be delivered upon settlement of the derivatives may differ materially from current estimates. Reasonable changes in assumptions could materially affect the estimated fair value of the derivative liability.

Fair Value Measured on a Nonrecurring Basis

During the nine months ended September 30, 2022 and 2021, there were no re-measurements to fair value of financial assets and liabilities that are measured at fair value on a nonrecurring basis.

8

Prepaid expenses and other current assets consisted of the following:

Property and equipment, net, consisted of the following:

Depreciation expense for the nine months ended September 30, 2022 and 2021 was $0.7 million and $0.3 million, respectively.

Accrued expenses and other current liabilities consisted of the following:

The Company’s significant license agreements are disclosed in Note 7, “License Agreements”, in the audited financial statements for the year ended December 31, 2021, and notes thereto, included in the Solid Form 8-K. Since the date of those financial statements, there have been no material changes to the Company’s license agreements.

Series A Convertible Preferred Stock

In October 2020, the Company entered into a securities purchase agreement (“Series A Agreement”) with certain investors to sell up to 19,498,328 shares of Series A Convertible Preferred Stock which included up to 9,028,486 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share and up to 10,469,842 shares of Series A-2 Convertible Preferred Stock at $6.0401 per share. The Series A Agreement contemplated an initial closing which occurred in October 2020 and an interim closing (“Interim Closing”), which occurred in November 2020. The Series A Agreement also contemplated two tranche closings, for Convertible Preferred Stock to be purchased at a stated price per share, contingent upon certain closing conditions, unless waived by the holders of 67% of the outstanding shares of Convertible Preferred Stock (the “Requisite Holders”).

At the initial closing in October 2020, the Company issued 6,741,915 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share for gross cash proceeds of $32.6 million less issuance costs of $313,000, resulting in net proceeds of $32.3 million. In addition, at the initial closing, the Company issued 1,900,507 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share in consideration of the cancellation of $9.2 million in notes issued under a note purchase agreement entered into by the Company and noteholders in 2020.

9

At the Interim Closing, the Company issued 51,737 shares of Series A-1 Convertible Preferred Stock at a price of $4.8321 per share for gross cash proceeds of $250,000. In addition, at the Interim Closing, the Company issued 334,327 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share in consideration of the cancellation of $1.6 million in notes issued under a note purchase agreement entered into by the Company and noteholders in 2019.

On June 25, 2021, the Series A Agreement was amended to: (i) add an additional purchaser for purposes of the Second Tranche closing initially outlined in the Series A Agreement, (ii) provide that the shares issued at the Second Tranche closing will be shares of Series A-1 Convertible Preferred Stock instead of Series A-2 Convertible Preferred Stock and will be issued at a price per share of $4.8321 and (iii) increase the authorized issuance of the Series A Convertible Preferred Stock to 21,023,162 shares, which included up to 15,788,241 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share and up to 5,234,921 shares of Series A-2 Convertible Preferred Stock at $6.0401 per share.

On July 1, 2021, the Company obtained approval from the Requisite Holders to waive the conditions to the Second Tranche closing and closed the Second Tranche of the Series A Convertible Preferred Stock financing. At the Second Tranche closing, the Company issued 6,759,754 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share for gross cash proceeds of $32.6 million, less issuance costs of $78,000, as well as payment in service of $44,373, resulting in net proceeds of $32.5 million. An investor elected not to participate in the Second Tranche closing, resulting in 1,055,441 shares of Series A-1 Convertible Preferred Stock automatically converting into 1,055,441 shares of common stock at $4.8321 per share, or $5.1 million, in accordance with the Company’s Amended and Restated Certificate of Incorporation.

On February 24, 2022, the Company and the Requisite Holders entered into the second amendment to the Series A Agreement to increase the authorized issuance of the Series A Convertible Preferred Stock to 27,900,000 shares, which included up to 14,732,800 shares of Series A-1 Convertible Preferred Stock at $4.8321 per share and 13,087,248 shares of Series A-2 Convertible Preferred Stock at $2.4161 per share. Concurrently, on February 24, 2022, the Company obtained approval from the Requisite Holders to waive the conditions to the Third Tranche closing and closed the Third Tranche of the Series A Convertible Preferred Stock financing. At the Third Tranche closing, the Company issued 13,087,248 shares of Series A-2 Convertible Preferred Stock at $2.4161 per share for gross cash proceeds of $31.6 million, less issuance costs of $47,571, resulting in net proceeds of $31.5 million.

The Company is authorized to issue up to 43,000,000 shares of common stock, of which 6,406,278 shares were issued and outstanding at September 30, 2022.

The holders of the Company’s common stock are entitled to one vote for each share of common stock held, subject to certain limitations pertaining to the Convertible Preferred Stock. Common stockholders are entitled to receive dividends, as may be declared by the Board of Directors, subject to the preferential dividend rights of Convertible Preferred Stock. No dividends were declared or paid during the nine months ended September 30, 2022. In the event of any voluntary or involuntary liquidation, dissolution, winding up of the Company or deemed liquidation event, the holders of shares of common stock then outstanding shall be entitled to be paid out of the assets of the Company available for distribution to its stockholders after payment shall be made to the holders of the Convertible Preferred Stock.

The Company has reserved shares of common stock for the conversion or exercise of the following securities:

Equity Incentive Plan

In 2019, the Company’s Board of Directors adopted the 2019 Equity Incentive Plan (the “2019 Plan”), under which the Company may grant options and restricted stock to its employees and certain non-employees. The 2019 Plan was amended in July 2021, in connection with the Second Tranche closing, to increase the number of shares of common stock authorized and reserved for issuance under the 2019 Plan from 3,103,085 shares to 5,006,242 shares. The 2019 Plan was also amended in February 2022, in connection with the Third Tranche closing, to increase the number of shares of common stock authorized and reserved for issuance under the 2019 Plan from 5,006,242 shares to 8,688,053 shares.

The Company may grant options to purchase authorized but unissued shares of the Company’s common stock. Options granted under the 2019 Plan include incentive stock options that can be granted only to the Company’s employees and non-statutory stock options that can be granted to the Company’s employees, consultants, advisors, and directors. The 2019 Plan also permits the Company to issue restricted stock awards.

10

Option awards are granted with an exercise price equal to the fair value of the Company’s common stock at the date of grant. No grant may have a term in excess of ten years. Options granted under the 2019 Plan are exercisable in whole or in part at any time subsequent to vesting, subject to continued service to the Company.

Stock Options

For the nine months ended September 30, 2022, the Company granted 91,512 stock options under the 2019 Plan. The weighted-average grant-date exercise price of the stock options granted during the nine months ended September 30, 2022 was $0.56.

The following table summarizes total stock compensation by department for the nine months ended September 30, 2022:

Restricted Stock

A summary of the Company’s non-vested restricted common stock shares activity for the nine months ended September 30, 2022 is presented below:

11. Commitments and Contingencies

Operating Leases

On December 12, 2019, the Company entered into an operating lease which commenced on May 1, 2020, for office and laboratory space in Florida, which expires in April of 2025. The Company has the right to extend the lease for two additional five-year periods at a market rate as determined by the landlord and agreed to by the Company.

On January 1, 2021, the Company entered into an additional operating lease for office and laboratory space in Florida, which expires in December 2022. The Company has the right to extend the lease for an additional twelve-month period at a market rate as determined by the landlord and agreed to by the Company. The Company is expecting to use the option to extend the lease by an additional one-year period, until December 31, 2023.

On August 1, 2021, the Company entered into another operating lease for laboratory space in Florida, which expires in December 2022. The Company has the right to extend the lease for three additional one-year periods at a market rental rate as determined by the landlord and agreed to by the Company. The Company is expecting to use the option to extend the lease by an additional one-year period, until December 31, 2023.

On January 10, 2022, the Company entered an operating lease which commenced on April 4, 2022, for office and laboratory space in Florida, which expires in October 2032. The Company has the right to extend the lease for two additional five-year periods at a market rate as determined by the landlord and agreed to by the Company.

On January 17, 2022, the Company entered into an operating lease which commenced on February 16, 2022, for office and laboratory space in North Carolina, which expires in February 2024. The Company has the right to extend the lease for one additional two-year period at a market rate as determined by the landlord and agreed to by the Company.

11

The following table is a summary of the components of net lease cost for the nine months ended September 30, 2022:

Supplemental cash flow information related to leases for the nine months ended September 30, 2022 is as follows:

As of September 30, 2022, the Company’s operating leases were measured using a weighted-average incremental borrowing rate of 8.7% over a weighted-average remaining lease term of 7.3 years.

The total operating lease liabilities are presented on the Company’s condensed balance sheet based on maturity dates. $1.1 million of the total operating liabilities is classified under “operating lease liabilities, current” for the portion due within twelve months, and $2.7 million is classified under “operating lease liabilities, non-current”. Rent expense for the nine months ended September 30, 2021 under ASC 840, Leases was $0.65 million.

The Company’s future minimum lease payments as of September 30, 2022, are as follows:

The Company has a related party relationship with a university and a research foundation. The research foundation is a separate corporation that manages intellectual property that arises from the research activities of the university faculty and staff. The Company’s two Founders, who also serve on the Board of Directors of the Company, are employed by the university, own 5,000,000 shares of the Company’s common stock and are compensated as consultants by the Company. The Founders were both paid $75,000 by the Company in the nine months ended September 30, 2022 and $75,000 by the Company in the nine months ended September 30, 2021 pursuant to their consulting agreements with the Company. These amounts were recorded on the condensed statements of operations and comprehensive loss for the nine months ended September 30, 2022 and 2021, accordingly.

As discussed in Note 7, “License Agreements,” in the audited financial statements for the year ended December 31, 2021, and notes thereto, included in the Solid Form 8-K, the Company has entered into multiple licensing agreements with the university and a research foundation and recorded $105,000 and $1,850,000 of research and development net expense in the condensed statements of operations and comprehensive loss for the nine months ended September 30, 2022 and 2021, accordingly. Additionally, the condensed financial statements as of December 31, 2021 include a liability with respect to the first milestone payment of $50,000 related to the license that was paid during the period ended September 30, 2022.

On June 27, 2022, the Company announced a restructuring (the “Restructuring”) to extend its cash runway while furthering the development of its pipeline. The Restructuring was completed in connection with a challenging economic environment and changes to the Company’s Friedreich’s ataxia program. As part of the Restructuring, the Company reduced its workforce by approximately 47%, or 33 full-time employees, resulting in restructuring charges of approximately $0.3 million. The reduction in force was completed by the end of July 2022.

12

The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the condensed financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated through the date the condensed financial statements were available to be issued. The Company is not aware of any material subsequent events other than as disclosed below.

Operating Lease Termination

On October 21, 2022, the Company terminated the lease agreement with Laser Investment Group, LLC that was executed on January 10, 2022, as discussed in Note 11. The Company paid a $2.0 million termination fee to relieve all of its remaining obligations under the lease.

13

Exhibit 99.4

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

Introduction

On September 29, 2022, Solid Biosciences Inc. (the “Company” or “Solid”) entered into an Agreement and Plan of Merger (the “Merger Agreement”) by and among the Company, Greenland Merger Sub LLC, a Delaware limited liability corporation and a wholly owned subsidiary of the Company (“Transitory Subsidiary”), and AavantiBio, Inc., a Delaware corporation (“AavantiBio”). The Merger Agreement provided for the acquisition of AavantiBio by the Company through the merger of Transitory Subsidiary into AavantiBio, with AavantiBio surviving as a wholly owned subsidiary of the Company (the “Acquisition”). The Acquisition was completed on December 2, 2022. In connection with the Acquisition, on September 29, 2022, the Company entered into securities purchase agreements (the “Securities Purchase Agreement”) with several accredited investors pursuant to which Solid agreed to issue and sell to the investors in a private placement (the “Private Placement”) an aggregate of 10,638,290 shares of Solid’s common stock, at a price per share of $7.05. The Private Placement closed immediately following the closing of the Acquisition.

The following unaudited pro forma condensed combined financial information is presented to illustrate the estimated effect of the acquisition by the Company of 100% of the issued and outstanding shares of AavantiBio pursuant to the terms of the Merger Agreement for a purchase price of approximately $9.2 million (the “Purchase Price”) as discussed in Note 2.

It is anticipated that the Acquisition will be accounted for as a business combination in which the Company, as the accounting acquirer, will record the assets acquired and liabilities assumed of AavantiBio at their fair values as of the acquisition date. As discussed in Note 2 below, the estimated fair values of the assets acquired and liabilities assumed by the Company are preliminary and there can be no assurance that such finalization will not result in material changes to the unaudited pro forma condensed combined financial information presented. Additionally, the pro forma presentation of the Private Placement presented herein is also preliminary. Actual results will differ from the unaudited pro forma condensed combined financial information provided herein once the Company has completed a detailed analysis. There can be no assurance that such finalization of the items above will not result in material changes to the unaudited pro forma condensed combined financial information presented.

Assumptions and estimates underlying the unaudited pro forma adjustments set forth in the unaudited pro forma condensed combined financial statements are described in the accompanying notes. The unaudited pro forma adjustments represent management’s estimates based on information available as of the date of these unaudited pro forma condensed combined financial statements and are subject to change as additional information becomes available and analyses are performed.

The unaudited pro forma condensed combined balance sheet as of September 30, 2022 gives effect to the Acquisition as if it took place on September 30, 2022 and combines the historical balance sheets of Solid and AavantiBio as of such date. The unaudited pro forma condensed combined statements of operations for the nine months ended September 30, 2022 and for the year ended December 31, 2021 give effect to the Acquisition as if it took place as of January 1, 2021 and such statements combine the historical results of Solid and AavantiBio for each period. The historical financial statements of Solid and AavantiBio have been adjusted to give pro forma effect to events that are reasonable and supportable at the date hereof.

The unaudited pro forma condensed combined financial information does not give effect to the potential impact of current financial conditions, regulatory matters, operating efficiencies or other savings or expenses that may be associated with the integration of the two companies, if any. The unaudited pro forma condensed combined financial information is preliminary and has been prepared for informational purposes only and is not necessarily indicative of the financial position or results of operations in future periods or the results that actually would have been realized had the Company acquired AavantiBio during the specified periods.

The unaudited pro forma condensed combined financial information, including the notes thereto, should be read in conjunction with the separate Solid historical financial statements and management’s discussion and analysis of financial condition and results of operations included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 filed with the Securities and Exchange Commission on March 14, 2022 and the Company’s Quarterly Report on Form 10-Q for the three months ended September 30, 2022 filed with the Securities and Exchange Commission on November 10, 2022. The unaudited pro forma condensed combined financial information, including the notes thereto, should also be read in conjunction with the separate AavantiBio historical financial statements included in the Company’s Current Report on Form 8-K (Exhibit No. 99.3) filed with the Securities and Exchange Commission on December 5, 2022 and the AavantiBio management’s discussion and analysis of financial condition and results of operations for the year ended December 31, 2021 included in the Company’s Definitive Proxy Statement filed with the Securities and Exchange Commission on November 7, 2022.

UNAUDITED PRO FORMA CONDENSED COMBINED BALANCE SHEET (in thousands, except share and per share data) As of September 30, 2022