0000950170-23-006377 | 10-K | XBRL Viewer

Organization

Alaunos Therapeutics, Inc., which is referred to herein as “Alaunos,” or the “Company,” is a clinical-stage oncology-focused cell therapy company developing adoptive TCR therapies, designed to treat multiple solid tumor types in large cancer patient populations with unmet clinical needs. On January 25, 2022, the Company changed its corporate name from ZIOPHARM Oncology, Inc. to Alaunos Therapeutics, Inc. The Company is leveraging its proprietary, non-viral Sleeping Beauty gene transfer platform and its novel cancer mutation hotspot TCR library to design and manufacture personalized cell therapies that target neoantigens arising from common tumor-related mutations in key oncogenic genes, including KRAS, TP53 and EGFR.

The Company’s operations to date have consisted primarily of conducting research and development and raising capital to fund those efforts. In May 2021, the Company announced that it will be winding down its existing Controlled IL-12 clinical program for the treatment of recurrent glioblastoma multiforme. The Company continues to seek a partner for this program.

The Company’s amended and restated certificate of incorporation authorizes it to issue 420,000,000 shares of common stock. As of December 31, 2022, there were 240,410,761 shares of common stock outstanding and an additional 33,330,964 shares of common stock reserved for issuance pursuant to outstanding stock options and warrants.

The accompanying financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities and commitments in the normal course of business. The Company follows the guidance of Accounting Standards Codification, or ASC, Topic 205-40, Presentation of Financial Statements - Going Concern, in order to determine whether there is substantial doubt about its ability to continue as a going concern for one year after the date its financial statements are issued. This evaluation initially does not take into consideration the potential mitigating effect of management's plans that have not been fully implemented as of the date the financial statements are issued. When substantial doubt exists, management evaluates whether the mitigating effect of its plans sufficiently alleviates the substantial doubt about the Company's ability to continue as a going concern. The mitigating effect of management's plans, however, is only considered if both (i) it is probable that the plans will be effectively implemented within one year after the date that the financial statements are issued and (ii) it is probable that the plans, when implemented, will mitigate the relevant conditions or events that raise substantial doubt about the entity's ability to continue as a going concern within one year after the date that the financial statements are issued.

The Company has operated at a loss since its inception in 2003 and has no recurring revenue from operations. The Company anticipates that losses will continue for the foreseeable future. As of December 31, 2022, the Company had approximately $53.0 million of cash, cash equivalents and restricted cash. The restricted cash of $13.9 million at December 31, 2022 is related to the Company's debt agreement (refer to Note 4, Debt). The Company’s accumulated deficit at December 31, 2022 was approximately $880.6 million. Given its current development plans and cash management efforts, the Company anticipates cash resources will be sufficient to fund operations into the fourth quarter of 2023. The Company’s ability to continue operations after its current cash resources are exhausted depends on future events, including its ability to obtain additional financing or to achieve profitable operations, as to which no assurances can be given, nor are within the Company's control. If adequate additional funds are not available when required, or if the Company is unsuccessful in entering into partnership agreements for further development of its product candidates, management may need to curtail its development efforts and planned operations to conserve cash until sufficient additional capital is raised. There can be no assurances that such a plan would be successful.

Based on the current cash forecast and the Company's dependence on its ability to obtain additional financing to fund its operations after the current resources are exhausted, about which there can be no certainty, management has determined that the Company's present capital resources will not be sufficient to fund its planned operations for at least one year from the issuance date of the financial statements, and substantial doubt as to the Company's ability to continue as a going concern exists. This forecast of cash resources is forward-looking information that involves risks and uncertainties, and the actual amount of expenses could vary materially and adversely as a result of a number of factors.

Financings

12 Months Ended

Dec. 31, 2022

Text Block [Abstract]

Financings

2021 Loan and Security Agreement

On August 6, 2021, the Company entered into a Loan and Security Agreement, or the Loan and Security Agreement, with Silicon Valley Bank and affiliates of Silicon Valley Bank, or collectively, SVB. The Loan and Security Agreement provided for an initial term loan of $25.0 million funded at the closing, or the Term A Tranche, with an additional tranche of $25.0 million available if certain funding and clinical milestones were met by August 31, 2022, or the Term B Tranche.

Effective December 28, 2021, the Company, entered into a First Amendment to the Loan and Security Agreement. We refer to the Loan and Security Agreement, as so amended, as the Amended Loan and Security Agreement.

The Amended Loan and Security Agreement extended the interest-only period through August 31, 2022. Certain milestones specified in the Amended Loan and Security Agreement were not met by the Company on or prior to August 31, 2022, and therefore, the interest-only period was not extended beyond August 31, 2022. The Amended Loan and Security Agreement also eliminated the Term B Tranche, which remained unfunded, leaving only the Term A Tranche, or the SVB Facility. Under the Amended Loan and Security Agreement, the SVB Facility will mature on August 1, 2023.

Refer to Note 4, Debt, for further discussion of the Loan and Security Agreement and the Amended Loan and Security Agreement.

2022 Equity Distribution Agreement

On August 12, 2022, the Company entered into an Equity Distribution Agreement, or the Equity Distribution Agreement, with Piper Sandler & Co., or Piper Sandler, pursuant to which the Company can offer and sell, from time to time at its sole discretion, shares of its common stock having an aggregate offering price of up to $50.0 million through Piper Sandler as its sales agent in an "at the market offering." Piper Sandler will receive a commission of 3.0% of the gross proceeds of any common stock sold under the Equity Distribution Agreement. During the year ended December 31, 2022, there have been no sales of the Company's common stock under the Equity Distribution Agreement.

2022 Public Offering

On November 29, 2022, the Company entered into an underwriting agreement, or the Underwriting Agreement, with Cantor Fitzgerald & Co., or the Underwriter, as the sole underwriter, relating to the issuance and sale in an underwritten offering, or the Offering, of 24,228,719 shares, or the Firm Shares, of the Company’s common stock to the Underwriter at a price of $0.6191 per share.

The net proceeds to the Company from the Offering were $14.7 million (before accounting for the partial exercise of the Underwriter's option as described below) after deducting underwriting discounts and commissions and offering expenses payable by the Company.

Under the terms of the Underwriting Agreement, the Company granted the Underwriter an option, exercisable for 30 days, to purchase up to an additional 3,634,307 shares of common stock, which we refer to, together with the Firm Shares, as the Shares, at the same price per share as the Firm Shares. On January 5, 2023, the Underwriter partially exercised its option to purchase 216,294 shares of common stock.

All of the Shares sold in the Offering were sold by the Company.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2022

Summary of Significant Accounting Policies

Basis of Presentation

The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Although the Company regularly assesses these estimates, actual results could differ from those estimates. Changes in estimates are recorded in the period in which they become known.

The Company’s most significant estimates and judgments used in the preparation of the financial statements are:

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Clinical trial expenses and other research and development expenses;

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Collaboration agreements;

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Fair value measurements of stock-based compensation; and

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Income taxes.

Subsequent Events

The Company evaluated all events and transactions that occurred after the balance sheet date through the date of this Annual Report on Form 10-K. The Company did not have any material subsequent events that impacted its financial statements or disclosures.

Cash and Cash Equivalents

Cash equivalents consist primarily of demand deposit accounts, certificates of deposit and deposits in short-term U.S. treasury money market mutual funds. Cash equivalents are stated at cost, which approximates fair market value.

Concentrations of Credit Risk

Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. The Company maintains cash accounts in commercial banks, which may, at times, exceed federally insured limits. The Company has not experienced any losses in such accounts. The Company believes it is not exposed to any significant credit risk on cash and cash equivalents.

Property and Equipment

Property and equipment are stated at cost, less accumulated depreciation and amortization. Expenditures for maintenance and repairs are charged to expense while the costs of significant improvements are capitalized. Depreciation and amortization is calculated on a straight-line basis using the following periods, which represent the estimated useful lives of the assets:


●	Office and computer equipment	3 years
●	Software	3 years
●	Laboratory equipment	5 years
●	Leasehold improvements	Life of the lease

Costs, including certain design, construction and installation costs related to assets that are under construction and are in the process of being readied for their intended use, are recorded as construction in progress and are not depreciated until such time as the subject asset is placed in service. Repairs and maintenance that do not extend the useful life of the asset are expensed as incurred. Upon sale, retirement or other disposition of these assets, the costs and related accumulated depreciation are removed from the respective accounts and any gain or loss on the disposition is included in the Statements of Operations.

Long-Lived Assets

Assessments of long-lived assets and the remaining useful lives of such long-lived assets are reviewed for impairment whenever a triggering event occurs or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. An asset, or group of assets, is considered to be impaired when the undiscounted estimated net cash flows expected to be generated by the asset, or group of assets, are less than its carrying amount. The impairment recognized is the amount by which the carrying amount exceeds the fair market value of the impaired asset, or group of assets, based on the present value of the expected future cash flows associated with the use of the asset.

Operating Segments

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the Company’s chief operating decision maker, in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment.

Warrants

The Company assesses whether warrants issued require accounting as derivatives. The Company determined that the warrants were (1) indexed to the Company’s own stock and (2) classified in stockholders’ equity in accordance with Financial Accounting Standards Board, or FASB, ASC Topic 815, Derivatives and Hedging. As such, the Company has concluded the warrants meet the scope exception for determining whether the instruments require accounting as derivatives and should be classified in stockholders’ equity.

Fair Value Measurements

The Company has certain financial assets and liabilities recorded at fair value which have been classified as Level 1, 2 or 3 within the fair value hierarchy as described in the accounting standards for fair value measurements.

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Level 1—Quoted prices in active markets for identical assets or liabilities.

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Level 2—Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

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Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Assets and liabilities measured at fair value on a recurring and nonrecurring basis as of December 31, 2022 and 2021 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2022		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	38,058	$	38,058	$	—	$	—


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2021		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	75,222	$	75,222	$	—	$	—

The cash equivalents represent demand deposit accounts and deposits in a short-term United States treasury money market mutual fund quoted in an active market and classified as a Level 1 asset. There have been no changes to the valuation methods during the years ended December 31, 2022 and 2021. The Company had no financial assets or liabilities that were classified as Level 2 or Level 3 during the years ended December 31, 2022 and 2021.

Fair value of non-financial instruments

The Company evaluates its assets for impairment whenever events or changes in circumstances indicate that indicators of impairment exist. In those evaluations, the Company compares estimated future undiscounted cash flows generated by each asset (or asset group) to the carrying value of the asset (or asset group) to determine if an impairment charge is required. If the undiscounted cash flows test fails, the Company estimates the fair value of the asset (or asset group) to determine the impairment.

During 2021, following the Company's strategic restructuring and further cost reduction initiatives, the Company determined that changes in the intended use of its Boston office represented an indicator of impairment, resulting in an impairment charge of $0.6 million to the right-of-use asset. In addition, the Company impaired approximately $0.1 million of leasehold improvements and various other assets associated with its decision to close the Company's Boston office. Refer to Note 8, Leases, for further details.

Revenue Recognition from Collaboration Agreements

Revenue for the year ended December 31, 2022 consisted of $2.9 million and for the year ended December 31, 2021 consisted of $0.4 million. For the years ended December 31, 2022 and 2021, the Company recognized revenue through its Collaboration Agreement with Solasia Pharma K.K. primarily due to the achievement of milestones, as further described in Note 9, Commitments and Contingencies.

The Company primarily generates revenue through collaboration arrangements with strategic partners for the development and commercialization of product candidates. The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers, or ASC 606. The core principle of ASC 606 is that an entity should recognize revenue to depict the transfer of promised goods and/or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and/or services. To determine the appropriate amount of revenue to be recognized for arrangements that the Company determines are within the scope of ASC 606, the Company performs the following steps: (i) identify the contract(s) with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract and (v) recognize revenue when (or as) each performance obligation is satisfied.

The Company recognizes collaboration revenue under certain of the Company’s license or collaboration agreements that are within the scope of ASC 606. The Company’s contracts with customers typically include promises related to licenses to intellectual property, research and development services and options to purchase additional goods and/or services. If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, up-front fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non-refundable, up-front fees.

Contracts that include an option to acquire additional goods and/or services are evaluated to determine if such option provides a material right to the customer that it would not have received without entering into the contract. If so, the option is accounted for as a separate performance obligation. If not, the option is considered a marketing offer which would be accounted for as a separate contract upon the customer’s election.

The terms of the Company’s arrangements with customers typically include the payment of one or more of the following:(i) non-refundable, up-front payment, (ii) development, regulatory and commercial milestone payments, (iii) future options and (iv) royalties on net sales of licensed products. Accordingly, the transaction price is generally comprised of a fixed fee due at contract inception and variable consideration in the form of milestone payments due upon the achievement of specified events and tiered royalties earned when customers recognize net sales of licensed products. The Company measures the transaction price based on the amount of consideration to which it expects to be entitled in exchange for transferring the promised goods and/or services to the customer. The Company utilizes the most likely amount method to estimate the amount of variable consideration, to predict the amount of consideration to which it will be entitled. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. At the inception of each arrangement that includes development and regulatory milestone payments, the Company evaluates whether the associated event is considered probable of achievement and estimates the amount to be included in the transaction price using the most likely amount method. Milestone payments that are not within the control of the Company or the licensee, such as those dependent upon receipt of regulatory approval, are not considered to be probable of achievement until the triggering event occurs. At the end of each reporting period, the Company reevaluates the probability of achievement of each milestone and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenue and net loss in the period of adjustment. For arrangements that include sales-based royalties, including milestone payments based upon the achievement of a certain level of product sales, the Company recognizes revenue upon the later of: (i) when the related sales occur or (ii) when the performance obligation to which some or all of the payment has been allocated has been satisfied (or partially satisfied). Consideration that would be received for optional goods and/or services is excluded from the transaction price at contract inception.

The Company allocates the transaction price to each performance obligation identified in the contract on a relative standalone selling price basis. However, certain components of variable consideration are allocated specifically to one or more particular performance obligations in a contract to the extent both of the following criteria are met: (i) the terms of the payment relate specifically to the efforts to satisfy the performance obligation or transfer the distinct good or service and (ii) allocating the variable amount of consideration entirely to the performance obligation or the distinct good or service is consistent with the allocation objective of the standard whereby the amount allocated depicts the amount of consideration to which the entity expects to be entitled in exchange for transferring the promised goods or services. The Company develops assumptions that require the use of judgment to determine the standalone selling price for each performance obligation identified in each contract. The key assumptions utilized in determining the standalone selling price for each performance obligation may include forecasted revenue, development timelines, estimated research and development costs, discount rates, likelihood of exercise and probabilities of technical and regulatory success.

Revenue is recognized based on the amount of the transaction price that is allocated to each respective performance obligation when or as the performance obligation is satisfied by transferring a promised good and/or service to the customer. For performance obligations that are satisfied over time, the Company recognizes revenue by measuring the progress toward complete satisfaction of the performance obligation

using a single method of measuring progress which depicts the performance in transferring control of the associated goods and/or services to the customer. The Company uses input methods to measure the progress toward the complete satisfaction of performance obligations satisfied over time. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenue and net loss in the period of adjustment.

Research and Development Costs

As part of the process of preparing the Company's financial statements, the Company is required to estimate its accrued research and development expenses. This process involves reviewing open contracts and purchase orders, communicating with its personnel to identify services that have been performed on its behalf and estimating the level of service performed and the associated costs incurred for the services when the Company has not yet been invoiced or otherwise notified of the actual costs. The majority of the Company's service providers invoice the Company in arrears for services performed, on a predetermined schedule or when contractual milestones are met; however, a few require advanced payments. The Company makes estimates of its accrued expenses as of each balance sheet date in its financial statements based on facts and circumstances known to it at that time. Examples of estimated accrued research and development expenses include fees paid to:

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clinical research organizations, or CROs, in connection with performing research services on its behalf and clinical trials;

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investigative sites or other providers in connection with clinical trials;

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vendors in connection with preclinical and clinical development activities; and

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vendors related to product manufacturing, development, and distribution of preclinical and clinical supplies.

The Company bases its expenses related to preclinical studies and clinical trials on its estimates of the services received and efforts expended pursuant to quotes and contracts with CROs that conduct and manage clinical trials on its behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. 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 the clinical expense. Payments under some of these contracts depend on factors such as the completion of clinical trial milestones. In accruing service fees, the Company estimates the time period over which services will be performed, enrollment of patients, number of sites activated 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 its estimate, the Company adjusts the accrual or amount of prepaid expense accordingly. Although the Company does not expect its estimates to be materially different from amounts actually incurred, its understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in it reporting amounts that are too high or too low in any particular period. To date, the Company has not made any material adjustments to its prior estimates of accrued research and development expenses.

Income Taxes

Income taxes are accounted for under the liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences of temporary differences between the financial statement carrying amounts and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the year in which the temporary differences are expected to be recovered or settled. The Company evaluates the realizability of its deferred tax assets and establishes a valuation allowance when it is more likely than not that all or a portion of deferred tax assets will not be realized.

The Company accounts for uncertain tax positions using a “more-likely-than-not” threshold for recognizing and resolving uncertain tax positions. The evaluation of uncertain tax positions is based on factors including, but not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity and changes in facts or circumstances related to a tax position. The Company evaluates this tax position on an annual basis. The Company also accrues for potential interest and penalties related to unrecognized tax benefits in income tax expense (Refer to Note 12, Income Taxes).

Accounting for Stock-Based Compensation

Stock-based compensation cost is measured at the grant date based on the estimated fair value of the award and is recognized as expense over the employee’s requisite service period. Stock-based compensation expense is based on the number of awards ultimately expected to vest and is reduced for forfeitures as they occur. Consistent with prior years, the Company uses the Black-Scholes option pricing model, which requires estimates of the expected term option holders will retain their options before exercising them and the estimated volatility of the Company’s common stock price over the expected term.

The Company recognized the full impact of its share-based employee payment plans in the Statements of Operations for each of the years ended December 31, 2022 and 2021 and did not capitalize any such costs on the Balance Sheets. The Company recognized $3.0 million of compensation expense related to stock options for the year ended December 31, 2022 and $7.4 million of compensation expense related to stock options for the year ended December 31, 2021. The Company recognized $0.5 million of compensation expense, related to restricted stock for the year ended December 31, 2022 and $3.4 million for the year ended December 31, 2021 (refer to Note 13, Stock Option Plan). The total compensation expense relating to vesting of stock options and restricted stock awards for the year ended December 31, 2022 was $3.5 million and $10.8 million for the year ended December 31, 2021. The following table presents share-based compensation expense included in the Company’s Statements of Operations:


	Year Ended December 31,
(in thousands)	2022		2021
Research and development		868		2,598
General and administrative		2,660		8,176
Stock-based compensation expense	$	3,528	$	10,774

The fair value of each stock option is estimated at the date of grant using the Black-Scholes option pricing model. The estimated weighted-average fair value of stock options granted to employees in the year ended December 31, 2022 was approximately $0.77 per share and was approximately $2.62 per share for the year ended December 31, 2021. Assumptions regarding volatility, expected term, dividend yield and risk-free interest rate are required for the Black-Scholes model. The volatility assumption is based on the Company’s historical experience. The risk-free interest rate is based on a U.S. treasury note with a maturity similar to the option award’s expected life. The expected life represents the average period of time that options granted are expected to be outstanding. The Company calculated expected term using the simplified method described in SEC Staff Accounting Bulletin, or SAB, No. 107 and No. 110 as it continues to meet the requirements promulgated in SAB No. 110. The assumptions for volatility, expected life, dividend yield and risk-free interest rate are presented in the table below:


	Year Ended December 31,
	2022	2021
Risk-free interest rate	1.63 – 4.21%	0.50 – 1.36%
Expected life in years	5.27 – 6.25	5.50 – 6.25
Expected volatility	74.49 – 88.75%	72.53 – 74.80%
Expected dividend yield	—%	—%

Net Loss per Share

Basic net loss per common share is computed by dividing net loss applicable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net loss per share is computed using the weighted-average number of shares of common stock outstanding during the period, plus the dilutive effect of outstanding options and warrants, using the treasury stock method and the average market price of the Company’s common stock during the applicable period, unless their effect on net loss per share is antidilutive. The effect of computing diluted net loss per common share was antidilutive for any potentially issuable shares of common stock from the conversion of stock options, unvested restricted stock and warrants and, as such, have been excluded from the calculation.

The computation of basic and diluted net loss per share consists of the following:


	Year Ended December 31,
	2022			2021
Net loss	$	(37,730	)	$	(78,751	)
Weighted-average common shares outstanding, basic and diluted		217,130,311			214,399,074
Net loss per share, basic and diluted	$	(0.17	)	$	(0.37	)

Certain shares related to some of the Company’s outstanding common stock options, unvested restricted stock and warrants have not been included in the computation of diluted net loss per share for the years ended December 31, 2022 and 2021 as the result would be antidilutive. Such potential common shares on December 31, 2022 and 2021 consist of the following:


	December 31,
	2022		2021
Common stock options		10,408,622		10,665,869
Inducement stock options		-		32,500
Unvested restricted stock		939,062		1,198,580
Warrants		22,922,342		22,922,342
		34,270,026		34,819,291

New Accounting Pronouncements

In November 2021, the FASB issued Accounting Standards Update, or ASU, 2021-10, Government Assistance (Topic 832): Disclosures by Business entities about Government Assistance, which requires business entities to disclose information about certain government assistance that they receive. Entities must comply with the new disclosure requirements if they account for transactions with government entities under the (1) contribution model or (2) grant model by analogy. The Company adopted this standard effective January 1, 2022, with no material impact upon adoption.

In July 2021, the FASB issued ASU 2021-05, Leases (Topic 842): Lessors – Certain Leases with Variable Lease Payments, which requires lessors to classify as operating leases those leases with variable lease payments that do not depend on an index or rate if another classification (i.e. sales-type or direct financing) would result in a commencement date (‘day 1’) selling loss. The Company adopted this standard effective January 1, 2022, with no material impact upon adoption.

In May 2021, the FASB issued ASU 2021-04, Earnings Per Share (Topic 260), Debt - Modifications and Extinguishments (Subtopic 470-50), Compensation - Stock Compensation (Topic 718), and Derivatives and Hedging - Contracts in Entity’s Own Equity (Subtopic 815- 40): Warrant modifications, which clarifies an issuer’s accounting for certain modifications or exchanges of freestanding equity-classified written call options (e.g. warrants) that remain equity-classified after modification or exchange. The Company adopted this standard effective January 1, 2022, with no material impact upon adoption.

Debt

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Debt

4. Debt

The carrying values of the Company's debt obligation were as follows:


	December 31,
($ in thousands)	2022			2021
Loan and Security Agreement	$	17,395		$	25,209
Unamortized discount on Loan and Security Agreement		(630	)		(1,091	)
Total debt		16,765			24,118
Less: long-term debt, current		(16,765	)		(7,868	)
Long-term debt	$	—		$	16,250

On August 6, 2021, the Company entered into the Loan and Security Agreement. The Loan and Security Agreement provided for an initial term loan of $25.0 million funded at the closing, with an additional tranche of $25.0 million available if certain funding and clinical milestones were met by August 31, 2022. On December 28, 2021, the Company entered into the Amended Loan and Security Agreement.

Under the terms of the Amended Loan and Security Agreement, the SVB Facility was modified to eliminate the additional $25.0 million tranche, which remained unfunded, leaving only the initial $25.0 million as the full amount available under the SVB Facility. The SVB Facility bears interest at a floating rate per annum on outstanding loans, payable monthly, at the greater of (a) 7.75% and (b) the current published U.S. prime rate, plus a margin of 4.5%. As of December 31, 2022, interest on the outstanding loans was 12.00%. The Amended Loan and Security Agreement provided for an interest-only period through August 31, 2022. Commencing on September 1, 2022, aggregate outstanding borrowings became repayable in twelve consecutive, equal monthly installments of principal plus accrued interest.

All outstanding obligations under the Amended Loan and Security Agreement are due and payable on August 1, 2023. The Company will also owe SVB 5.75% of the original principal amounts borrowed as a final payment. The Company is permitted to make up to two prepayments, subject to a prepayment premium of the amount being prepaid, ranging from 1.00% to 2.00%, of the SVB Facility, each such prepayment to be at least $5.0 million plus all accrued and unpaid interest on the portion being prepaid.

As a result of not achieving certain milestones specified in the Amended Loan and Security Agreement on or prior to August 31, 2022, the Company was required to cash collateralize half of the sum of the then-outstanding principal amount of the SVB Facility, plus an amount equal to 5.75% of the original principal amount of the SVB Facility. As of December 31, 2022, the Company has collateralized $13.9 million, which is classified as restricted cash on the Balance Sheet. So long as no event of default has occurred and subject to certain other terms related to the remaining outstanding balance under the SVB Facility being satisfied, $2.5 million will be released from the collateral account following the eighth scheduled payment of principal and interest, and a further $4.0 million will be released following the tenth scheduled payment of principal and interest. The SVB Facility and related obligations under the Amended Loan and Security Agreement are secured by substantially all of the Company’s properties, rights and assets, except for its intellectual property (which is subject to a negative pledge under the Amended Loan and Security Agreement). In addition, the Amended Loan and Security Agreement contains customary representations, warranties, events of default and covenants.

In connection with its entry into the Loan and Security Agreement, the Company issued to SVB warrants to purchase (i) up to 432,844 shares of the Company’s common stock, in the aggregate, and (ii) up to an additional 432,842 shares of common stock, in the aggregate, in the event the Company achieved certain clinical milestones, in each case at an exercise price per share of $2.22.

In connection with its entry into the Amended Loan and Security Agreement, the Company amended and restated the warrants issued to SVB. As amended and restated, the warrants are for up to 649,615 shares of the Company's common stock, in the aggregate, at an exercise price per share of $1.16, or the SVB Warrants. The SVB Warrants expire on August 6, 2031.

The issuance costs for the Loan and Security Agreement, including the Amended Loan and Security Agreement, were approximately $1.2 million and primarily related to the warrants issued to SVB, which will be amortized into interest expense over the period to August 1, 2023. Interest expense, including the amortization of issuance costs, was $3.2 million for the year ended December 31, 2022 and $1.2 million for the year ended December 31, 2021.

The fair value of the Amended Loan and Security Agreement as of December 31, 2022 approximates its face value.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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Property, Plant and Equipment [Abstract]

Property and Equipment, net

12 Months Ended

Dec. 31, 2022

Property and Equipment, net

Property and equipment, net, consists of the following:


	December 31,
($ in thousands)	2022			2021
Office and computer equipment	$	2,183		$	2,534
Software		1,291			1,236
Leasehold improvements		9,561			9,474
Laboratory equipment		5,232			5,110
		18,267			18,354
Less: accumulated depreciation		(9,807	)		(7,413	)
Property and equipment, net	$	8,460		$	10,941

Depreciation expense for the year ended December 31, 2022 was $2.8 million and was $2.6 million for the year ended December 31, 2021. During the year ended December 31, 2021, the Company impaired property and equipment by $0.1 million. Refer to Note 3, Summary of Significant Accounting Policies, for further details.

Accrued Expenses

12 Months Ended

Dec. 31, 2022

Payables and Accruals [Abstract]

Accrued Expenses

Accrued expenses consist of the following:


($ in thousands)	2022		2021
Clinical	$	2,200	$	1,677
Employee compensation		1,160		1,922
Professional services		534		825
Preclinical services		198		363
Manufacturing services		1,177		1,056
Other consulting services		16		66
Other		169		167
	$	5,454	$	6,076

Related Party Transactions

12 Months Ended

Dec. 31, 2022

Related Party Transactions

Collaboration with Vineti Inc.

On July 9, 2020, the Company entered into a master service agreement and statement of work with Vineti, Inc., or Vineti. Pursuant to the agreements, Vineti is developing a software platform to coordinate and orchestrate the order, cell collection and manufacturing process for the Company’s T-cell therapy, or TCR-T, clinical programs. Heidi Hagen, who became a director of the Company in June 2019 and resigned November 2, 2021 and was appointed the Company's interim Chief Executive Officer on February 25, 2021 and resigned on August 30, 2021, is a co-founder and former officer, of Vineti. During the year ended December 31, 2022, the Company did not incur expenses for services performed by Vineti, compared to $0.4 million during the year ended December 31, 2021.

WaterMill Settlement Agreement

On February 4, 2021, the Company entered into an agreement, or the Settlement Agreement, with WaterMill Asset Management Corp. and Robert W. Postma, or collectively, the WaterMill Parties. Pursuant to the Settlement Agreement, the Company increased the size of its board of directors from eight to nine directors and appointed Mr. Postma to fill the newly created directorship.

In accordance with the Settlement Agreement, the Company agreed to reimburse the WaterMill Parties for up to $0.4 million of their reasonable out-of-pocket expenses in connection with (i) the WaterMill Parties' solicitation of written consents from our stockholders to vote in favor of certain proposals, as set forth in the definitive consent statement filed by the WaterMill Parties on October 30, 2020, and (ii) the negotiation, execution, and effectuation of the Settlement Agreement. As of February 19, 2021, the Company has fully reimbursed the WaterMill Parties an aggregate amount of $0.4 million.

Joint Venture with TriArm Therapeutics/Eden BioCell

On December 18, 2018, the Company and TriArm Therapeutics, Ltd., or TriArm, launched Eden BioCell, Ltd., or Eden BioCell, as a joint venture to lead commercialization of the Company’s Sleeping Beauty-generated CAR-T therapies in the People’s Republic of China (including Macau and Hong Kong), Taiwan and Korea. The Company licensed to Eden BioCell the rights in Greater China for its third-generation Sleeping Beauty-generated CAR-T therapies targeting the CD19 antigen. Eden BioCell is owned equally by the Company and TriArm and the parties share decision-making authority. TriArm has contributed $10.0 million to Eden BioCell and has committed up to an additional $25.0 million to this joint venture. TriArm also manages all clinical development in the territory pursuant to a master services agreement between TriArm and Eden BioCell. James Huang was the founder and serves as managing partner of Panacea Venture, which is an investor in TriArm. Mr. Huang is the Chair of the Company's board of directors and has been a director since July 2020. He also serves as a member of Eden BioCell’s board of directors.

For the years ended December 31, 2022 and 2021, Eden BioCell incurred a net loss and the Company continues to have no commitment to fund its operations. In September 2021, TriArm and Alaunos mutually agreed to dissolve the Eden BioCell joint venture. The joint venture agreement has been terminated and the Eden BioCell entity is in the process of being dissolved. Refer to Note 15, Joint Venture, for further details.

Leases

12 Months Ended

Dec. 31, 2022

Leases, Operating [Abstract]

Leases

Operating Leases

In June 2012, the Company entered into a master lease for the Company’s office in Boston, Massachusetts, which was originally set to expire in August 2016, but was renewed through August 31, 2021. On April 22, 2021, the Company extended its lease for a portion of office space in Boston. The renewal of the portion of the Company's office space was originally set to expire on August 31, 2021, but was extended through August 31, 2026. As of December 31, 2022, and December 31, 2021, a total security deposit of $0.1 million is included in deposits on the Company’s balance sheet. In December 2021, the Company made the decision to move its operations away from its former corporate office in Boston. As described in Note 3, Summary of Significant Accounting Policies, the Company's change in the intended use of the Boston office represented an indicator of impairment. The Company determined the aggregate carrying value of the asset group (approximately $1.4 million as of December 31, 2021) was in excess of the aggregate estimated fair value and recorded an impairment charge of $0.6 million to the right-of-use asset and approximately $0.1 million to associated property and equipment during the year ended December 31, 2021. The fair value was determined based on the amount and timing of estimated net future cash flows, discounted at a risk-adjusted rate of 10%.

On March 12, 2019, the Company entered into a lease agreement for office and lab space in Houston, Texas at MD Anderson through April 2021. Under the terms of the lease agreement, the Company leases approximately 1,038 square feet and was required to make rental payments

at an average monthly rate of approximately $2 thousand through April 2021. On October 15, 2019, the Company entered into a lease agreement for additional office and laboratory space in Houston through February 2027. Under the terms of the lease, the Company leases from MD Anderson, approximately 8,443 square feet and is initially required to make rental payments of approximately $17 thousand per month through February 2027, subject to an annual base rent increase of approximately 3.0% throughout the term. Effective April 7, 2020, the Company leased an additional 5,594 square feet from MD Anderson. The Company is initially required to make rental payments of approximately $12 thousand per month through February 2027, subject to an annual base rent increase of approximately 3.0% throughout the term.

On December 15, 2020, the Company entered into a second agreement with MD Anderson to lease additional space on MD Anderson’s campus (the “2020 Lease”). The Company is initially required to make rental payments of approximately $37 thousand per month through April 2028, subject to an annual base rent increase of approximately 3.0% throughout the term beginning in April 2023. The 2020 Lease may be extended for one additional five-year term at the Company's election.

In April 2022, the Company modified the 2020 Lease, which reduced the Company's leased space from 18,111 square feet to 3,228 square feet. As a result, the associated lease liability and right-of-use asset were remeasured to $0.4 million based on revised lease payments. A gain of $0.1 million was recorded on the lease modification during the year ended December 31, 2022. The Company is initially required to make payments of approximately $7 thousand per month through April 2028, subject to an annual base rent increase of approximately 3.0% throughout the term. The 2020 Lease may be extended for one additional five-year term at the Company's election.

The components of lease expense were as follows:


	Year Ended December 31,
($ in thousands)	2022			2021
Operating lease cost	$	756		$	1,394
Total lease cost	$	756		$	1,394
Weighted-average remaining lease term (years)		4.13			5.58
Weighted-average discount rate		8.26	%		8.00	%

The Company paid $0.8 million for amounts included in the measurement of the lease liabilities for the year-ended December 31, 2022. The Company did not recognize new operating lease assets obtained in exchange for operating lease liabilities for the year-ended December 31, 2022.

As of December 31, 2022, the maturities of the Company’s operating lease liabilities were as follows (in thousands):


Maturity of Lease Liabilities	Operating Leases
2023		757
2024		780
2025		804
2026		712
2027		158
Thereafter		31
Total lease payments		3,242
Less: imputed interest		(496	)
Present value of lease payments	$	2,746

In June 2022, the Company executed an agreement to sub-sublease 4,772 square feet of subleased office space in Boston. The term of the sub-sublease is from July 1, 2022 to June 30, 2025 and provides the sub-subtenant with an option to extend through to July 31, 2026. For the year ended December 31, 2022, the Company recognized $0.1 million in lease income, which is classified within other income (expense), net in the Statement of Operations. Under the current terms of the agreement, lease income for the remainder of the sub-sublease term is expected to be $0.2 million in 2023, $0.2 million in 2024 and $0.1 million in 2025.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2022

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Exclusive License Agreement with PGEN Therapeutics

On October 5, 2018, the Company entered into an exclusive license agreement, or License Agreement, with PGEN Therapeutics, or PGEN, a wholly owned subsidiary of Precigen Inc., or Precigen, which was formerly known as Intrexon Corporation. Pursuant to the terms of the

License Agreement, the Company has exclusive, worldwide rights to research, develop and commercialize (i) TCR products designed for neoantigens for the treatment of cancer, (ii) products utilizing Precigen’s RheoSwitch gene switch, or RTS, for the treatment of cancer, referred to as IL-12 Products and (iii) CAR products directed to (A) CD19 for the treatment of cancer, referred to as CD19 Products, and (B) BCMA for the treatment of cancer, subject to certain obligations to pursue such target under the License and Collaboration Agreement effective March 27, 2015 between us, Precigen and ARES TRADING S.A., a subsidiary of Merck KGaA, as assigned by Precigen to PGEN. Under the License Agreement, the Company also has exclusive, worldwide rights for certain patents relating to the Sleeping Beauty technology to research, develop and commercialize TCR products for both neoantigens and shared antigens for the treatment of cancer, referred to as TCR Products.

The Company is solely responsible for all aspects of the research, development and commercialization of the exclusively licensed products for the treatment of cancer. The Company is required to use commercially reasonable efforts, as defined in the License Agreement, to develop and commercialize IL-12 products, CD19 products and TCR Products.

In consideration of the licenses and other rights granted by PGEN, the Company pays PGEN an annual license fee of $0.1 million and the Company reimbursed PGEN for certain historical costs of the licensed programs.

The Company will make milestone payments totaling up to an additional $52.5 million for each exclusively licensed program upon the initiation of later stage clinical trials and upon the approval of exclusively licensed products in various jurisdictions. In addition, the Company will pay PGEN tiered royalties ranging from low-single digits to high-single digits on the net sales derived from the sale of any approved IL-12 products and CAR products. The Company will also pay PGEN royalties ranging from low-single digits to mid-single digits on the net sales derived from the sale of any approved TCR products, up to a maximum royalty amount of $100.0 million in the aggregate. The Company will also pay PGEN 20% of any sublicensing income received by us relating to the licensed products. The Company is responsible for all development costs associated with each of the licensed products.

PGEN will pay the Company royalties ranging from low-single digits to mid-single digits on the net sales derived from the sale of PGEN’s CAR products, up to a maximum royalty amount of $100.0 million. No royalty amounts were incurred during the years ended December 31, 2022 and 2021.

In October 2020, the Company entered into an amendment to the License Agreement relating to the transfer of certain materials and PGEN’s obligations to provide transition assistance relating to the IL-12 products.

License Agreement and 2015 Research and Development Agreement —The University of Texas MD Anderson Cancer Center

On January 13, 2015, the Company, together with Precigen, entered into the MD Anderson License with MD Anderson (which Precigen subsequently assigned to PGEN). Pursuant to the MD Anderson License, the Company, together with PGEN, holds an exclusive, worldwide license to certain technologies owned and licensed by MD Anderson, including technologies relating to novel CAR T-cell therapies, non-viral gene transfer systems, genetic modification and/or propagation of immune cells and other cellular therapy approaches, Natural Killer, or NK Cells, and TCRs, arising from the laboratory of Laurence Cooper, M.D., Ph.D., who served as the Company’s Chief Executive Officer from May 2015 until February 2021 and was formerly a tenured professor of pediatrics at MD Anderson.

On August 17, 2015, the Company, Precigen and MD Anderson entered into the 2015 R&D Agreement to formalize the scope and process for the transfer by MD Anderson, pursuant to the terms of the MD Anderson License, of certain existing research programs and related technology rights, as well as the terms and conditions for future collaborative research and development of new and ongoing research programs. The rights and obligations of Precigen under the 2015 R&D Agreement were assigned to the Company pursuant to the Fourth Amendment to 2015 R&D Agreement which was entered into on September 19, 2019 (the “Fourth Amendment”) with an effective date of October 5, 2018. The activities under the 2015 R&D Agreement are directed by a joint steering committee comprised of two members from the Company and one member from MD Anderson.

As provided under the MD Anderson License, the Company provided funding for research and development activities in support of the research programs under the 2015 R&D Agreement for a period of three years and in an amount of no less than $15.0 million and no greater than $20.0 million per year. On November 14, 2017, the Company entered into an amendment to the 2015 R&D Agreement, extending its term until April 15, 2021. In connection with the execution of the 2019 R&D Agreement described below, on October 22, 2019, the Company amended the 2015 R&D Agreement to extend the term of the 2015 R&D Agreement until December 31, 2026 and to allow cash resources on hand at MD Anderson under the 2015 R&D Agreement to be used for development costs under the 2019 Research and Development Agreement, or the 2019 R&D Agreement, which we entered into on October 22, 2019, with MD Anderson, pursuant to which we agreed to collaborate with respect to the TCR program.

The term of the MD Anderson License expires on the last to occur of (a) the expiration of all patents licensed thereunder, or (b) the twentieth anniversary of the date of the MD Anderson License; provided, however, that following the expiration of the term of the MD Anderson

License, the Company, together with Precigen, shall then have a fully-paid up, royalty free, perpetual, irrevocable and sublicensable license to use the licensed intellectual property thereunder. After ten years from the date of the MD Anderson License and subject to a 90-day cure period, MD Anderson will have the right to convert the MD Anderson License into a non-exclusive license if the Company and Precigen are not using commercially reasonable efforts to commercialize the licensed intellectual property on a case-by-case basis. After five years from the date of the MD Anderson License and subject to a 180-day cure period, MD Anderson will have the right to terminate the MD Anderson License with respect to specific technology(ies) funded by the government or subject to a third-party contract if the Company and Precigen are not meeting the diligence requirements in such funding agreement or contract, as applicable. MD Anderson may also terminate the agreement with written notice upon material breach by the Company and Precigen, if such breach has not been cured within 60 days of receiving such notice. In addition, the MD Anderson License will terminate upon the occurrence of certain insolvency events for both the Company and Precigen and may be terminated by the mutual written agreement of the Company, PGEN, and MD Anderson.

2019 Research and Development Agreement—The University of Texas MD Anderson Cancer Center

Under the 2019 R&D Agreement, the Company and MD Anderson will, among other things, collaborate on programs to expand the Company's TCR library and conduct clinical trials. The activities under the 2019 R&D Agreement are directed by a joint steering committee comprised of two members from the Company and one member from MD Anderson.

The Company will own all inventions and intellectual property developed under the 2019 R&D Agreement and the Company will retain all rights to all, intellectual property, patentable or not, for oncology products manufactured using non-viral gene transfer technologies under the 2019 R&D Agreement, including the Company's Sleeping Beauty technology. The Company has granted MD Anderson an exclusive license for such intellectual property to develop and commercialize autologous TCR products manufactured using viral gene transfer technologies, and any products outside the field of oncology and a non-exclusive license for allogenic TCR products manufactured using viral-based technologies.

Under the 2019 R&D Agreement, the Company agreed, beginning on January 1, 2021, to reimburse MD Anderson up to a total of $20.0 million for development costs under the 2019 R&D Agreement, after the funds from the 2015 R&D Agreement are exhausted. In addition, the Company will pay MD Anderson royalties on net sales of its TCR products. The Company is required to make performance-based payments upon the successful completion of clinical and regulatory benchmarks relating to its TCR products. The aggregate potential benchmark payments are $36.5 million, of which only $3.0 million will be due prior to the first marketing approval of the Company's TCR products. The royalty rates and benchmark payments owed to MD Anderson may be reduced upon the occurrence of certain events. The Company also agreed to sell its TCR products to MD Anderson at preferential prices and will sell the Company's TCR products in Texas exclusively to MD Anderson for a limited period of time following the first commercial sale of the Company's TCR products. For the year ended December 31, 2022, the Company incurred clinical expenses of $0.8 million from MD Anderson related to this agreement, compared to $0.3 million for the year ended December 31, 2021.

The 2019 R&D Agreement will terminate on December 31, 2026 and either party may terminate the 2019 R&D Agreement following written notice of a material breach. The 2019 R&D Agreement also contains customary provisions related to indemnification obligations, confidentiality and other matters.

In connection with the execution of the 2019 R&D Agreement, on October 22, 2019, the Company issued MD Anderson a warrant to purchase 3,333,333 shares of the Company's common stock, which is referred to as the MD Anderson Warrant. The MD Anderson Warrant has an initial exercise price of $0.001 per share, expires on December 31, 2026, and vests in four parts upon the occurrence of certain clinical milestones. As of December 31, 2022, the milestones have not been met.

License Agreement with the NCI

On May 28, 2019, the Company entered into a patent license agreement, or the Patent License, with the NCI. Pursuant to the Patent License, the Company holds an exclusive, worldwide license to certain intellectual property to develop and commercialize patient-derived (autologous), peripheral blood T-cell therapy products engineered by transposon-mediated gene transfer to express TCRs reactive to mutated KRAS, TP53 and EGFR neoantigens. In addition, pursuant to the Patent License, the Company holds an exclusive, worldwide license to certain intellectual property for manufacturing technologies to develop and commercialize autologous, peripheral blood T-cell therapy products engineered by non-viral gene transfer to express TCRs, as well as a non-exclusive, worldwide license to certain additional manufacturing technologies. On May 29, 2019, January 8, 2020, September 28, 2020, April 16, 2021, May 4, 2021 and August 13, 2021 the Company amended the Patent License to expand its TCR library to include additional TCRs reactive to mutated KRAS and TP53 neoantigens licensed from the NCI.

The terms of the Patent License require the Company to pay the NCI minimum annual royalties in the amount of $0.3 million, which amount will be reduced to $0.1 million once the aggregate minimum annual royalties paid by the Company equals $1.5 million.

The Company is also required to make performance-based payments upon successful completion of clinical and regulatory benchmarks relating to the licensed products. Of such payments, the aggregate potential benchmark payments are $4.3 million, of which aggregate payments of $3.0 million are due only after marketing approval in the United States or in Europe, Japan, Australia, China or India. The first benchmark payment of $0.1 million was paid during the year ended December 31, 2022 upon the initiation of the Company's TCR-T Library Phase 1/2 Trial, which was a qualifying Phase 1 clinical trial under the terms of the Patent License.

In addition, the Company is required to pay the NCI one-time benchmark payments following aggregate net sales of licensed products at certain aggregate net sales ranging from $250.0 million to $1.0 billion. The aggregate potential amount of these benchmark payments is $12.0 million. The Company must also pay the NCI royalties on net sales of products covered by the Patent License at rates in the low to mid-single digits depending upon the technology included in a licensed product. To the extent the Company enters into a sublicensing agreement relating to a licensed product, the Company is required to pay the NCI a percentage of all consideration received from a sublicensee, which percentage will decrease based on the stage of development of the licensed product at the time of the sublicense.

The Patent License will expire upon expiration of the last patent contained in the licensed patent rights, unless terminated earlier. The NCI may terminate or modify the Patent License in the event of a material breach, including if the Company does not meet certain milestones by certain dates, or upon certain insolvency events that remain uncured following the date that is 90 days following written notice of such breach or insolvency event. The Company may terminate the Patent License, or any portion thereof, in the Company's sole discretion at any time upon 60 days’ written notice to the NCI. In addition, the NCI has the right to: (i) require the Company to sublicense the rights to the product candidates covered by the Patent License upon certain conditions, including if the Company is not reasonably satisfying required health and safety needs and (ii) terminate or modify the Patent License, including if the Company is not satisfying requirements for public use as specified by federal regulations.

For the year ended December 31, 2022 the Company incurred $0.7 million of expenses and incurred $0.5 million of expenses for the year ended December 31, 2021.

Cooperative Research and Development Agreement (CRADA) with the NCI

On January 9, 2017, the Company entered into a Cooperative Research and Development Agreement, or the CRADA, with the NCI. The purpose of this collaboration was to advance a personalized TCR-T approach for the treatment of solid tumors. Using the Company's Sleeping Beauty technology, the NCI would analyze a patient’s own cancer cells, identify their unique neoantigens and TCRs reactive against those neoantigens and then use the Company's Sleeping Beauty technology to transpose one or more TCRs into T cells for re-infusion. Research conducted under the CRADA will be at the direction of Steven A. Rosenberg, M.D., Ph.D., Chief of the Surgery Branch at the NCI, in collaboration with the Company's researchers.

The Company is responsible for providing the NCI with the test materials necessary for them to conduct their studies, and eventually, clinical trials pursuant to the CRADA. Inventions, data and materials discovered or produced in connection with performance of the research plan under the CRADA will remain the sole property of the party who produced the discovery. The parties will jointly own all inventions jointly discovered under the research plan. The owner of any invention under the CRADA will make the decision to file a patent covering the invention, or in the case of a jointly owned invention, the Company will have the first opportunity to file a patent covering the invention. If the Company fails to provide timely notice of its decision to the NCI or decides not to file a patent covering the joint invention, the NCI has the right to make the filing. For any invention solely owned by the NCI or jointly made by the NCI and the Company for which a patent application was filed, the U.S. Public Health service grants the Company an exclusive option to elect an exclusive or non-exclusive commercialization license. For inventions owned solely by the NCI or jointly owned by the NCI and the Company, which are licensed according to the terms described above, the Company agreed to grant to the U.S. government a non-exclusive, non-transferable, irrevocable and paid up license to practice the invention or have the invention practiced on its behalf throughout the world. The Company is also required to grant the U.S. government a non-exclusive, non-transferable, irrevocable and paid up license to practice the invention or have the invention practiced on its behalf throughout the world for any of the Company's solely owned inventions. The agreement may be terminated by any of the parties upon 60 days prior written consent.

The NCI has a cleared Investigational New Drug Application, or IND, that would permit them to begin this trial. To the Company's knowledge, the trial has not yet enrolled. The progress and timeline for this trial, including the timeline for dosing patients, are under control of the NCI.

In February 2019, the Company extended the CRADA with the NCI until January 9, 2022, committing an additional $5.0 million to this program; however, for the third and fourth quarters of 2021, the Company was not required to make payments toward the program as agreed with the NCI. Therefore, as of December 31, 2022, the Company made $3.8 million of payments under the February 2019 CRADA extension, and the NCI has agreed that this is full satisfaction of the agreement and no further payments are due under the $5.0 million commitment. In March 2022, the Company entered into an amendment to the CRADA that was retroactive, effective January 9, 2022 to extend the term of the

CRADA until January 9, 2023. In June 2022, the Company entered into the Fourth Amendment to the CRADA, or the CRADA Fourth Amendment, which, among other things, extended the term of the CRADA until January 9, 2025. In connection with the CRADA Fourth Amendment, the Company agreed to contribute $1.0 million per year, payable on a quarterly basis, beginning in the first quarter of 2023. The Company did not incur expenses under the CRADA for the year ended December 31, 2022, as compared to $1.3 million for the year ended December 31, 2021.

Patent and Technology License Agreement—The University of Texas MD Anderson Cancer Center and the Texas A&M University System

On August 24, 2004, the Company entered into a patent and technology license agreement with MD Anderson and the Texas A&M University System, which the Company refers to, collectively, as the Licensors. Under this agreement, the Company was granted an exclusive, worldwide license to rights (including rights to U.S. and foreign patent and patent applications and related improvements and know-how) for the manufacture and commercialization of two classes of organic arsenicals (water- and lipid-based) for human and animal use. The class of water-based organic arsenicals includes darinaparsin.

Under the terms of the agreement, the Company may be required to make additional payments to the Licensors upon achievement of certain milestones in varying amounts which, on a cumulative basis could total up to an additional $4.5 million. In addition, the Licensors are entitled to receive royalty payments on sales from a licensed product and will also be entitled to receive a portion of any fees that the Company may receive from a possible sublicense under certain circumstances. During the year ended December 31, 2022, $2.5 million was incurred as a one-time milestone payment under the terms of the agreement, compared to $0.1 million for the year ended December 31, 2021. The Company incurred $2 thousand in royalty expenses on sales under this agreement during the year ended December 31, 2022, and did not incur royalty expenses on sales under this agreement during the year ended December 31, 2021.

Collaboration Agreement with Solasia Pharma K.K.

On March 7, 2011, the Company entered into a License and Collaboration Agreement with Solasia Pharma K. K., or Solasia, which was amended on July 31, 2014 to include an exclusive worldwide license and amended on October 14, 2021 to revise certain payment schedule details, or, as so amended, the Solasia License and Collaboration Agreement. Pursuant to the Solasia License and Collaboration Agreement, the Company granted Solasia an exclusive license to develop and commercialize darinaparsin in both intravenous and oral forms and related organic arsenic molecules, in all indications for human use.

As consideration for the license, the Company is eligible to receive from Solasia development- and sales-based milestones, a royalty on net sales of darinaparsin, once commercialized, and a percentage of any sublicense revenue generated by Solasia. Solasia will be responsible for all costs related to the development, manufacturing and commercialization of darinaparsin. The Company’s licensors, as defined in the Solasia License and Collaboration Agreement, will receive a portion of all milestone and royalty payments made by Solasia to the Company in accordance with the terms of the Solasia License and Collaboration Agreement with the licensors, as described above.

In June 2022, Solasia announced that darinaparsin had been approved from relapsed or refractory Peripheral T-Cell Lymphoma by the Ministry of Health, Labor and Welfare in Japan. During the year ended December 31, 2022, the Company earned $2.9 million of collaboration revenue under the Solasia License and Collaboration Agreement primarily related to Solasia's achievement of certain sales-based milestones in Japan, compared to $0.4 million during the year ended December 31, 2021.

Warrants

12 Months Ended

Dec. 31, 2022

Warrants Disclosure [Abstract]

Warrants

10.

Warrants

In connection with the Company’s November 2018 private placement that provided net proceeds of approximately $47.1 million, the Company issued warrants to purchase an aggregate of 18,939,394 shares of common stock, which became exercisable six months after the closing of the private placement, or the November 2018 Warrants. The November 2018 Warrants had an exercise price of $3.01 per share and have a five-year term. The fair value of the November 2018 Warrants was estimated at $18.4 million using a Black-Scholes model with the following assumptions: expected volatility of 71%, risk free interest rate of 2.99%, expected life of five years and no dividends.

On July 26, 2019 and September 12, 2019, the Company entered into agreements with existing investors whereby the investors exercised the November 2018 Warrants for an aggregate of 17,803,031 shares of common stock, at an exercise price of $3.01 per share. Proceeds from the warrant exercise after deducting placement agent fees and other related expenses of $1.1 million were approximately $52.5 million.

The Company issued participating investors new warrants to purchase up to 17,803,031 additional shares of common stock, or the 2019 Warrants, as consideration for the warrant holders to exercise their November 2018 Warrants. The 2019 Warrants will expire on the fifth anniversary of the initial exercise date and have an exercise price of $7.00. The 2019 Warrants were valued using a Black-Scholes valuation model and resulted in a $60.8 million non-cash charge in the Company’s statement of operations in 2019.

On October 22, 2019, the Company entered into the 2019 R&D Agreement with MD Anderson. In connection with the execution of the 2019 R&D Agreement, the Company issued the MD Anderson Warrant to purchase 3,333,333 shares of common stock. The MD Anderson Warrant has an initial exercise price of $0.001 per share and grant date fair value of $14.5 million. The MD Anderson Warrant expires on December 31, 2026 and vests upon the occurrence of certain clinical milestones. The Company will recognize expense on the MD Anderson Warrant in the same manner as if the Company paid cash for services to be rendered. For the year ended December 31, 2022 and 2021, the Company did not recognize any expense related to the MD Anderson Warrant as the clinical milestones had not been achieved.

On August 6, 2021, the Company entered into the Loan and Security Agreement with SVB. Refer to Note 4, Debt. In connection with the Loan and Security Agreement, the Company issued SVB warrants to purchase 432,844 shares of common stock with an exercise price of $2.22 per share. The warrants have a ten-year life and were fully vested upon issuance. The fair value of the warrants was estimated at $0.8 million using a Black-Scholes model with the following assumptions: expected volatility of 79%, risk free interest rate of 1.31%, expected life of ten years and no dividends. On December 28, 2021, the Company entered into the Amended Loan and Security Agreement, as described in Note 4, Debt, in connection with which, the original warrants issued to SVB were amended and restated. As amended and restated, the SVB Warrants are for up to 649,615 shares of common stock, in the aggregate, at an exercise price per share of $1.16. The SVB Warrants expire on August 6, 2031 and were fully vested upon issuance. Using a Black-Scholes model with an expected volatility of 81%, risk free interest rate of 1.49%, expected life of 10 years and no dividends, the Company recorded a $0.2 million increase in the fair value of the SVB Warrants due to the modification of the SVB Warrants during the year ended December 31, 2021.

The Company assessed whether the SVB Warrants require accounting as derivatives. The Company determined that the SVB Warrants were (1) indexed to the Company’s own stock and (2) classified in stockholders’ equity in accordance with ASC 815, Derivatives and Hedging. As such, the Company has concluded the SVB Warrants meet the scope exception for determining whether the instruments require accounting as derivatives and should be classified in stockholders’ equity.

Restructuring

12 Months Ended

Dec. 31, 2022

Restructuring and Related Activities [Abstract]

Restructuring

11.

Restructuring

On September 27, 2021, in order to lower its existing cost structure in connection with the realignment of its business strategy, the Company announced a strategic reduction in force and notified approximately 60 full-time employees of its intention to terminate their services on or, in most cases, before November 30, 2021. Certain of the notified employees had employment agreements that provided for enhanced severance benefits. The severance benefits, apart from certain continuing Company-paid health care benefits for up to twelve months, were paid in 2021. The remaining benefits were paid in 2022, which reduced the severance benefits accrual to $0 as of December 31, 2022.

The Company incurred the following costs associated with termination benefit payments resulting from the strategic reduction in force:


	December 31,
($ in thousands)	2021
Research and development	$	2,368
General and administrative		1,289
Total severance expense	$	3,657

Income Taxes

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Income Taxes

12.

Income Taxes

There is no provision for income taxes because the Company has incurred operating losses since inception. The reported amounts of income tax expense for the years ended December 31, 2022 and 2021 differ from the amounts that would result from applying domestic federal statutory

tax rates to pretax losses primarily because of the changes in the valuation allowance. Significant components of the Company’s deferred tax assets at December 31, 2022 and 2021 are as follows:


	December 31,
(in thousands)	2022			2021
Deferred tax assets:
Net operating loss carryforwards	$	171,070		$	164,486
Start-up and pre-clinical studies		17,204			21,705
Research and development credit carryforwards		40,116			39,817
Stock-based compensation		698			706
Capitalized acquisition costs		2,180			2,946
Lease liability		618			1,278
Depreciation		239			102
Capitalized research expenses		5,156			-
Other		27			156
		237,308			231,196
Less valuation allowance		(236,827	)		(230,119	)
Total deferred tax assets		481			1,077

Right-of-use asset		(481	)		(1,077	)
Total deferred tax liabilities	$	(481	)	$	(1,077	)
Net deferred taxes	$	—		$	—

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. At December 31, 2022, the Company has aggregate net operating loss carryforwards for federal tax purposes of approximately $665.5 million, of which approximately $341.7 million expire at various dates through December 31, 2037 and approximately $323.8 million can be carried forward indefinitely. The Company also has approximately $497.9 million of state net operating loss carryforwards available to offset future state taxable income, expiring at various dates through 2042. Additionally, the Company has approximately $40.1 million of federal and state research and development credits at December 31, 2022, expiring in varying amounts through 2042, which may be available to reduce future taxes.

The Company has provided a valuation allowance for the full amount of its net deferred tax assets since it is more likely than not that these future benefits will not be realized. However, these deferred tax assets may be available to offset future income tax liabilities and expenses. The valuation allowance increased by $6.7 million in 2022 due primarily to net operating loss carryforwards and the increase in research and development credits.

Income taxes using the federal statutory income tax rate differ from the Company’s effective tax rate primarily due to non-deductible expenses related to the Company’s issuance of warrants along with the change in the valuation allowance on deferred tax assets.

A reconciliation of income tax expense (benefit) at the statutory federal income tax rate and income taxes as reflected in the financial statements is as follows:


	Year Ended December 31,
(in thousands)	2022			2021
Federal income tax at statutory rates		21	%		21	%
State income tax, net of federal tax benefit		3	%		3	%
Research and development credits		2	%		3	%
Research and development true-up		-2	%		0	%
Stock-based compensation		-1	%		-1	%
Federal/state rate change		-5	%		-2	%
Change in valuation allowance		-18	%		-24	%
Effective tax rate		0	%		0	%

The Company adopted ASC 740, Accounting for Uncertain Tax Positions on January 1, 2007. ASC 740 clarifies the accounting for uncertainty in income taxes recognized in an enterprise’s financial statements in accordance with FASB Statement No. 109, “Accounting for Income Taxes.” ASC 740 prescribes a recognition threshold and measurement of a tax position taken or expected to be taken in a tax return. The

Company did not establish any additional reserves for uncertain tax liabilities upon adoption of ASC 740. There were no adjustments to its uncertain tax positions in the years ended December 31, 2022 and 2021.

The Company has not recognized any interest and penalties in the statements of operations because of the Company’s net operating losses and tax credits that are available to be carried forward. When necessary, the Company will account for interest and penalties related to uncertain tax positions as part of its provision for federal and state income taxes. The Company does not expect the amounts of unrecognized benefits will change significantly within the next twelve months.

The Company is currently open to audit under the statute of limitations by the Internal Revenue Service and state jurisdictions for the years ended December 31, 1999 through 2022 to the extent net operating losses continue to be carried forward to 2022.

Beginning in 2022, the Tax Cuts and Jobs Act of 2017, or the Tax Act, eliminated the option to deduct research and development expenditures immediately in the year incurred and requires taxpayers to capitalize and amortize them over five years pursuant to IRC Section 174. The mandatory capitalization requirement had no impact to the overall deferred tax assets due to the Company's loss position and full valuation allowance.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI https://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Share-Based Payment Arrangement [Abstract]

Stock Option Plan

12 Months Ended

Dec. 31, 2022

Stock Option Plan

13.

Stock Option Plan

The Company adopted the 2012 Equity Incentive Plan, or the 2012 Plan, in May 2012. Including subsequent increases, the Company had reserved 14,000,000 shares for issuance. On December 31, 2022, there were 1,089,296 shares reserved for issuance and no shares available for future grant.

The Company adopted the 2020 Equity Incentive Plan, or the 2020 Plan, in June 2020. The Company reserved 21,000,000 shares for issuance plus a carryover of 1,066,275 shares from the 2012 Plan for a total of 22,066,275 shares. In addition, returning shares from the 2012 Plan are available for issuance under the 2020 Plan. As of December 31, 2022, there were 9,319,326 shares reserved for issuance and 15,460,088 shares available for future grant.

Stock options generally vest ratably in either quarterly or annual installments over three or four years, commencing on the first anniversary of the grant date and have contractual terms of ten years. Stock options to directors generally vest ratably over one or two years and have contractual terms of ten years. Stock options are valued using the Black-Scholes option pricing model and compensation is recognized based on such fair value over the period of vesting on a straight-line basis.

Proceeds from the option exercises during the year ended December 31, 2022 amounted to $21 thousand and during the year ended December 31, 2021 amounted to $1.0 million. The intrinsic value of these options amounted to $26 thousand for the year ended December 31, 2022 and $0.8 million for the year ended December 31, 2021.

Stock option activity under the Company's stock options plans for the years ending December 31, 2022 and 2021 were as follows:


(in thousands, except share and per share data)	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding, December 31, 2020		6,840,719			3.81
Granted		9,380,438			2.62
Exercised		(363,109	)		2.86
Cancelled		(5,192,179	)		3.65
Outstanding, December 31, 2021		10,665,869		$	2.87
Granted		4,697,500			1.08
Exercised		(26,250	)		0.80
Cancelled		(4,928,497	)		3.34
Outstanding, December 31, 2022		10,408,622		$	1.84		8.69	$	3
Options exercisable, December 31, 2022		3,891,598		$	2.46		8.08	$	—
Options exercisable, December 31, 2021		4,410,312		$	3.85		7.53	$	—
Options available for future grant, December 31, 2022		15,460,088

On December 31, 2022, total unrecognized compensation costs related to non-vested stock options outstanding amounted to $6.2 million. The cost is expected to be recognized over a weighted-average period of 1.92 years.

Restricted Stock

For the year ended December 31, 2022 the Company issued 280,000 shares of restricted stock and 1,601,224 in the year ended December 31, 2021 to employees and directors. During the year ended December 31, 2022, the Company repurchased 18,750 shares at a price of $2.41 per share to cover payroll taxes for one employee exercise, which is in accordance with the original terms of the award. There were no repurchases by the Company for the year ended December 31, 2021.

A summary of the status of restricted stock as of December 31, 2022 and 2021 is as follows:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested, December 31, 2020		786,280			3.08
Granted		1,601,224			2.60
Vested		(754,137	)		3.40
Cancelled		(434,787	)		3.45
Unvested, December 31, 2021		1,198,580		$	2.10
Granted		280,000			0.82
Vested		(306,617	)		2.28
Cancelled		(232,901	)		3.15
Unvested, December 31, 2022		939,062		$	1.40

As of December 31, 2022, there was $1.1 million of total unrecognized stock-based compensation expense related to non-vested restricted stock arrangements. The expense is expected to be recognized over a weighted-average period of 1.78 years.

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2022
Postemployment Benefits [Abstract]
Employee Benefit Plan	14. Employee Benefit Plan The Company sponsors a qualified 401(k) retirement plan under which employees are allowed to contribute certain percentages of their pay, up to the maximum allowed under Section 401(k) of the IRC, or the 401(k) Plan. The Company may make contributions to the 401(k) Plan at its discretion. The Company contributed approximately $0.5 million to the 401(k) Plan during the year ended December 31, 2022 and $0.7 million during the year ended December 31, 2021.

Joint Venture

12 Months Ended

Dec. 31, 2022

Equity Method Investments and Joint Ventures [Abstract]

Joint Venture

15.

Joint Venture

On December 18, 2018, the Company entered into a Framework Agreement with TriArm whereby the parties agreed to launch Eden BioCell to lead clinical development and commercialization of certain Sleeping Beauty-generated CAR-T therapies as set forth in a separate license agreement.

On January 3, 2019, Eden BioCell was incorporated in Hong Kong as a private company. Eden BioCell, the Company and TriArm entered into a Share Subscription Agreement on January 23, 2019, where the Company and TriArm agreed to contribute certain intellectual property, services and cash (only with respect to TriArm) to Eden BioCell to subscribe for a certain number of newly issued ordinary shares in the share capital of Eden BioCell.

The closing of the transaction occurred on July 5, 2019. The Framework Agreement and Share Subscription Agreements were each respectively amended to be effective as of this date. Upon consummation of the joint venture, Eden BioCell and the Company also entered into a license agreement, pursuant to which the Company licensed the rights to Eden BioCell for third generation Sleeping Beauty-generated CAR-T therapies targeting the CD19 antigen for the territory of China (including Macau and Hong Kong), Taiwan and Korea. TriArm and the Company each received a 50% equity interest in the joint venture in exchange for their contributions to Eden BioCell.

The Company determined that Eden BioCell was considered a variable interest entity, or VIE, and concluded that it is not the primary beneficiary of the VIE as it did not have the power to direct the activities of the VIE. As a result, the Company accounts for the equity interest in Eden BioCell under the equity method of accounting as it has the ability to exercise significant influence.

In March 2021, Eden BioCell began treating patients in a clinical trial with the Company’s investigational CD19 RPM CAR-T cell therapy, under the IND cleared by the Taiwan FDA in December 2020. In the first half of 2021, two patients were treated in this trial. The lead investigator at National Taiwan University in Taipei, has reported no serious adverse safety events in either of these patients. Laboratory results continue to support, as previously published, that non-viral Sleeping Beauty gene transfer is effective in genetically modifying autologous T-cells. Patients were infused two days after gene transfer, thus shortening the turnaround time and demonstrating an advantage over viral methods.

Based on laboratory data from the first two patients generated between March and May 2021, the TriArm/Eden team concluded, in concert with the investigator and the Company, that further process development work is required.

For the years ended December 31, 2022 and 2021, Eden BioCell incurred a net loss. In September 2021, TriArm and the Company mutually agreed to dissolve the joint venture, which has now been terminated. The Eden BioCell entity is in the process of being dissolved.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2022

Cash and Cash Equivalents

Basis of Presentation

The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP.

Use of Estimates

The Company’s most significant estimates and judgments used in the preparation of the financial statements are:

•

Clinical trial expenses and other research and development expenses;

•

Collaboration agreements;

•

Fair value measurements of stock-based compensation; and

•

Income taxes.

Subsequent Events

Concentrations of Credit Risk

Property and Equipment


●	Office and computer equipment	3 years
●	Software	3 years
●	Laboratory equipment	5 years
●	Leasehold improvements	Life of the lease

Long-Lived Assets

Operating Segments

Warrants

Fair Value Measurements

•

Level 1—Quoted prices in active markets for identical assets or liabilities.

•

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Assets and liabilities measured at fair value on a recurring and nonrecurring basis as of December 31, 2022 and 2021 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2022		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	38,058	$	38,058	$	—	$	—


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2021		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	75,222	$	75,222	$	—	$	—

Fair value of non-financial instruments

Revenue Recognition from Collaboration Agreements

Research and Development Costs

•

clinical research organizations, or CROs, in connection with performing research services on its behalf and clinical trials;

•

investigative sites or other providers in connection with clinical trials;

•

vendors in connection with preclinical and clinical development activities; and

•

vendors related to product manufacturing, development, and distribution of preclinical and clinical supplies.

Income Taxes

Accounting for Stock-Based Compensation


	Year Ended December 31,
(in thousands)	2022		2021
Research and development		868		2,598
General and administrative		2,660		8,176
Stock-based compensation expense	$	3,528	$	10,774


	Year Ended December 31,
	2022	2021
Risk-free interest rate	1.63 – 4.21%	0.50 – 1.36%
Expected life in years	5.27 – 6.25	5.50 – 6.25
Expected volatility	74.49 – 88.75%	72.53 – 74.80%
Expected dividend yield	—%	—%

Net Loss per Share

The computation of basic and diluted net loss per share consists of the following:


	Year Ended December 31,
	2022			2021
Net loss	$	(37,730	)	$	(78,751	)
Weighted-average common shares outstanding, basic and diluted		217,130,311			214,399,074
Net loss per share, basic and diluted	$	(0.17	)	$	(0.37	)


	December 31,
	2022		2021
Common stock options		10,408,622		10,665,869
Inducement stock options		-		32,500
Unvested restricted stock		939,062		1,198,580
Warrants		22,922,342		22,922,342
		34,270,026		34,819,291

New Accounting Pronouncements

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets and liabilities measured at fair value on a recurring and nonrecurring basis as of December 31, 2022 and 2021 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2022		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	38,058	$	38,058	$	—	$	—


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2021		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	75,222	$	75,222	$	—	$	—

Share-Based Compensation Expense Included in Statements of Operations

The following table presents share-based compensation expense included in the Company’s Statements of Operations:


	Year Ended December 31,
(in thousands)	2022		2021
Research and development		868		2,598
General and administrative		2,660		8,176
Stock-based compensation expense	$	3,528	$	10,774

Assumptions for Volatility, Expected life, Dividend Yield and Risk-free Interest Rate

The assumptions for volatility, expected life, dividend yield and risk-free interest rate are presented in the table below:


	Year Ended December 31,
	2022	2021
Risk-free interest rate	1.63 – 4.21%	0.50 – 1.36%
Expected life in years	5.27 – 6.25	5.50 – 6.25
Expected volatility	74.49 – 88.75%	72.53 – 74.80%
Expected dividend yield	—%	—%

Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method

The computation of basic and diluted net loss per share consists of the following:


	Year Ended December 31,
	2022			2021
Net loss	$	(37,730	)	$	(78,751	)
Weighted-average common shares outstanding, basic and diluted		217,130,311			214,399,074
Net loss per share, basic and diluted	$	(0.17	)	$	(0.37	)

Potentially Dilutive Shares Excluded from Computation of Diluted Net Loss Per Share

Such potential common shares on December 31, 2022 and 2021 consist of the following:


	December 31,
	2022		2021
Common stock options		10,408,622		10,665,869
Inducement stock options		-		32,500
Unvested restricted stock		939,062		1,198,580
Warrants		22,922,342		22,922,342
		34,270,026		34,819,291

Debt (Tables)

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Schedule of Debt

The carrying values of the Company's debt obligation were as follows:


	December 31,
($ in thousands)	2022			2021
Loan and Security Agreement	$	17,395		$	25,209
Unamortized discount on Loan and Security Agreement		(630	)		(1,091	)
Total debt		16,765			24,118
Less: long-term debt, current		(16,765	)		(7,868	)
Long-term debt	$	—		$	16,250

Property and Equipment, net (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Component of Property and Equipment, Net

Property and equipment, net, consists of the following:


	December 31,
($ in thousands)	2022			2021
Office and computer equipment	$	2,183		$	2,534
Software		1,291			1,236
Leasehold improvements		9,561			9,474
Laboratory equipment		5,232			5,110
		18,267			18,354
Less: accumulated depreciation		(9,807	)		(7,413	)
Property and equipment, net	$	8,460		$	10,941

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2022

Payables and Accruals [Abstract]

Component of Accrued Expenses

Accrued expenses consist of the following:


($ in thousands)	2022		2021
Clinical	$	2,200	$	1,677
Employee compensation		1,160		1,922
Professional services		534		825
Preclinical services		198		363
Manufacturing services		1,177		1,056
Other consulting services		16		66
Other		169		167
	$	5,454	$	6,076

Leases (Tables)

12 Months Ended

Dec. 31, 2022

Leases, Operating [Abstract]

Components of Lease Expense

The components of lease expense were as follows:


	Year Ended December 31,
($ in thousands)	2022			2021
Operating lease cost	$	756		$	1,394
Total lease cost	$	756		$	1,394
Weighted-average remaining lease term (years)		4.13			5.58
Weighted-average discount rate		8.26	%		8.00	%

Lessee, Operating Lease, Liability, Maturity

As of December 31, 2022, the maturities of the Company’s operating lease liabilities were as follows (in thousands):


Maturity of Lease Liabilities	Operating Leases
2023		757
2024		780
2025		804
2026		712
2027		158
Thereafter		31
Total lease payments		3,242
Less: imputed interest		(496	)
Present value of lease payments	$	2,746

Restructuring (Tables)

12 Months Ended

Dec. 31, 2022

Restructuring and Related Activities [Abstract]

Future termination benefit payments resulting from the strategic reduction in force

The Company incurred the following costs associated with termination benefit payments resulting from the strategic reduction in force:


	December 31,
($ in thousands)	2021
Research and development	$	2,368
General and administrative		1,289
Total severance expense	$	3,657

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Significant Component of Deferred Tax Assets

Significant components of the Company’s deferred tax assets at December 31, 2022 and 2021 are as follows:


	December 31,
(in thousands)	2022			2021
Deferred tax assets:
Net operating loss carryforwards	$	171,070		$	164,486
Start-up and pre-clinical studies		17,204			21,705
Research and development credit carryforwards		40,116			39,817
Stock-based compensation		698			706
Capitalized acquisition costs		2,180			2,946
Lease liability		618			1,278
Depreciation		239			102
Capitalized research expenses		5,156			-
Other		27			156
		237,308			231,196
Less valuation allowance		(236,827	)		(230,119	)
Total deferred tax assets		481			1,077

Right-of-use asset		(481	)		(1,077	)
Total deferred tax liabilities	$	(481	)	$	(1,077	)
Net deferred taxes	$	—		$	—

Reconciliation of Income Tax Expense (Benefit)

A reconciliation of income tax expense (benefit) at the statutory federal income tax rate and income taxes as reflected in the financial statements is as follows:


	Year Ended December 31,
(in thousands)	2022			2021
Federal income tax at statutory rates		21	%		21	%
State income tax, net of federal tax benefit		3	%		3	%
Research and development credits		2	%		3	%
Research and development true-up		-2	%		0	%
Stock-based compensation		-1	%		-1	%
Federal/state rate change		-5	%		-2	%
Change in valuation allowance		-18	%		-24	%
Effective tax rate		0	%		0	%

Stock Option Plans (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Stock Option Activity Under Stock Option Plan

Stock option activity under the Company's stock options plans for the years ending December 31, 2022 and 2021 were as follows:


(in thousands, except share and per share data)	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding, December 31, 2020		6,840,719			3.81
Granted		9,380,438			2.62
Exercised		(363,109	)		2.86
Cancelled		(5,192,179	)		3.65
Outstanding, December 31, 2021		10,665,869		$	2.87
Granted		4,697,500			1.08
Exercised		(26,250	)		0.80
Cancelled		(4,928,497	)		3.34
Outstanding, December 31, 2022		10,408,622		$	1.84		8.69	$	3
Options exercisable, December 31, 2022		3,891,598		$	2.46		8.08	$	—
Options exercisable, December 31, 2021		4,410,312		$	3.85		7.53	$	—
Options available for future grant, December 31, 2022		15,460,088

Summary of Non-Vested Restricted Stock

A summary of the status of restricted stock as of December 31, 2022 and 2021 is as follows:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested, December 31, 2020		786,280			3.08
Granted		1,601,224			2.60
Vested		(754,137	)		3.40
Cancelled		(434,787	)		3.45
Unvested, December 31, 2021		1,198,580		$	2.10
Granted		280,000			0.82
Vested		(306,617	)		2.28
Cancelled		(232,901	)		3.15
Unvested, December 31, 2022		939,062		$	1.40

Organization - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash, cash equivalents and restricted cash	$ 52,996	$ 76,054	$ 115,069
Accumulated deficit	(880,627)	$ (842,852)
Restricted cash related to the Company's debt agreement	$ 13,900
Common stock, shares authorized	420,000,000	350,000,000
Common stock, shares outstanding	240,410,761	216,127,443
Common Stock [Member]
Common stock, shares authorized	420,000,000
Common stock, shares outstanding	240,410,761
Common stock reserved for future issuance	33,330,964

Financings - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended
	Jan. 05, 2023	Nov. 29, 2022	Aug. 12, 2022	Dec. 31, 2022	Aug. 06, 2021
Debt Instrument [Line Items]
Aggregate offering price				$ 14,724
At The Market Offering [Member]
Debt Instrument [Line Items]
Number of additional option available to the underwriter to purchase		3,634,307
Underwriting Agreement [Member]
Debt Instrument [Line Items]
Common stock issuance		24,228,719
Underwriter par or stated value per share		$ 0.6191
Threshold period for exercise or conversion of stock		30 days
Underwriting Agreement [Member] \| Stock Option [Member]
Debt Instrument [Line Items]
Sale of stock consideration received on transaction		$ 14,700
Underwriting Agreement [Member] \| Stock Option [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Stock issued during period	216,294
Equity Distribution Agreement [Member]
Debt Instrument [Line Items]
Stock issued during period				0
Aggregate offering price			$ 50,000
Percentage Of Commission On Gross Proceeds From Sale Of Common Stock			3.00%
Silicon Valley Bank [Member] \| Term A Tranche [Member]
Debt Instrument [Line Items]
Loan and Security Agreement					$ 25,000
Silicon Valley Bank [Member] \| Term B Tranche [Member]
Debt Instrument [Line Items]
Additonal tranche facility					$ 25,000

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	$ 3,528	$ 10,774
Weighted average fair value of stock option granted	$ 0.77	$ 2.62
Asset Impairment Charges	$ 0	$ 740
Operating Lease Impairment Loss		600
Collaboration revenue	$ 2,922	398
Office and computer equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment useful life	3 years
Software [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment useful life	3 years
Laboratory equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment useful life	5 years
Leasehold improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Asset Impairment Charges		100
Estimated useful life	Life of the lease
Stock Options [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	$ 3,000	7,400
Restricted Stock [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	500	3,400
Stock Options and Restricted Stock [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	$ 3,500	$ 10,800

Summary of Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 38,058	$ 75,222
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 38,058	$ 75,222

Summary of Significant Accounting Policies - Stock-Based Compensation Expense Included in Statement of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,528	$ 10,774
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	868	2,598
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 2,660	$ 8,176

Summary of Significant Accounting Policies - Fair Value of Stock Options Assumptions Using Black-Scholes Option Valuation Model (Detail)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Risk-free interest rate, Minimum	1.63%	0.50%
Risk-free interest rate, Maximum	4.21%	1.36%
Expected volatility, Minimum	74.49%	72.53%
Expected volatility, Maximum	88.75%	74.80%
Maximum [Member]
Expected life in years	6 years 3 months	6 years 3 months
Minimum [Member]
Expected life in years	5 years 3 months 7 days	5 years 6 months

Summary of Significant Accounting Policies - Earning Per share Basic and Diluted (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share [Abstract]
Net loss	$ (37,730)	$ (78,751)
Weighted average common shares outstanding, basic	217,130,311	214,399,074
Weighted average common shares outstanding, diluted	217,130,311	214,399,074
Net loss per share, basic	$ (0.17)	$ (0.37)
Net loss per share, diluted	$ (0.17)	$ (0.37)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Summary of Significant Accounting Policies - Potential Dilutive Shares Excluded from Computation of Diluted Net Loss Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	34,270,026	34,819,291
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	22,922,342	22,922,342
Common stock options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	10,408,622	10,665,869
Stock Options [Member] \| Two Thousand Twelve Stock Option Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	32,500
Unvested Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	939,062	1,198,580

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total debt	$ 16,765	$ 24,118
Less: current portion of long-term debt	(16,765)	(7,868)
Long-term debt	0	16,250
Silicon Valley Bank Loan [Member]
Debt Instrument [Line Items]
Loan and Security Agreement	17,395	25,209
Unamortized discount on Loan and Security Agreement	$ (630)	$ (1,091)

Debt - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Dec. 28, 2021	Aug. 06, 2021	Dec. 31, 2022	Dec. 31, 2021
Line of Credit Facility [Line Items]
Line of credit facility, interest rate		4.50%
Restricted cash related to the Company's debt agreement			$ 13.9
Interest expense amortized date			Aug. 01, 2023
Interest expense			$ 3.2	$ 1.2
Term Loan [Member]
Line of Credit Facility [Line Items]
Initial borrowing		$ 25.0
Interest rate			12.00%
Percentage of original principal due as a final payment		5.75%
Line of credit facility, interest rate		7.75%
Line of credit facility additional tranche amount		$ 25.0
Silicon Valley Bank Loan [Member]
Line of Credit Facility [Line Items]
Warrants issued	649,615
Warrants expiration date	Aug. 06, 2031
Description of payment terms		The Company will also owe SVB 5.75% of the original principal amounts borrowed as a final payment. The Company is permitted to make up to two prepayments, subject to a prepayment premium of the amount being prepaid, ranging from 1.00% to 2.00%, of the SVB Facility, each such prepayment to be at least $5.0 million plus all accrued and unpaid interest on the portion being prepaid.
Debt instrument description of variable rate basis			The SVB Facility bears interest at a floating rate per annum on outstanding loans, payable monthly, at the greater of (a) 7.75% and (b) the current published U.S. prime rate, plus a margin of 4.5%
Prepayment premium		$ 5.0
Number of warrants issued		432,844
Warrant exercise per share	$ 1.16	$ 2.22
Additional number warrants issued		432,842
Debt instrument, initial maturity date			Aug. 01, 2023
Silicon Valley Bank Loan [Member] \| Debt Instrument Redemption Period One \| Maximum
Line of Credit Facility [Line Items]
Percentage of prepayments premium			2.00%
Silicon Valley Bank Loan [Member] \| Debt Instrument Redemption Period One \| Minimum
Line of Credit Facility [Line Items]
Percentage of prepayments premium			1.00%
Silicon Valley Bank Loan [Member] \| Term Loan [Member]
Line of Credit Facility [Line Items]
Restricted cash related to the Company's debt agreement			$ 13.9
Silicon Valley Bank Loan [Member] \| Term Loan [Member] \| Tenth Scheduled Payment
Line of Credit Facility [Line Items]
Proceeds from bank debt	$ 4.0
Silicon Valley Bank Loan [Member] \| Term Loan [Member] \| Eight Scheduled Payment
Line of Credit Facility [Line Items]
Proceeds from bank debt	2.5
Silicon Valley Bank Loan [Member] \| Warrants [Member]
Line of Credit Facility [Line Items]
Issuance costs	$ 1.2

Property and Equipment, net - Component of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 18,267	$ 18,354
Less: accumulated depreciation	(9,807)	(7,413)
Property and equipment, net	8,460	10,941
Office and computer equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	2,183	2,534
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	1,291	1,236
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	9,561	9,474
Laboratory equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 5,232	$ 5,110

Property and Equipment, net - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Depreciation	$ 2,759	$ 2,597
Asset Impairment Charges	$ 0	740
Leasehold improvements [Member]
Asset Impairment Charges		$ 100

Accrued Expenses - Component of Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Clinical	$ 2,200	$ 1,677
Employee compensation	1,160	1,922
Professional services	534	825
Preclinical services	198	363
Manufacturing services	1,177	1,056
Other consulting services	16	66
Other	169	167
Total	$ 5,454	$ 6,076

Related Party Transactions - Additional Information (Detail) - USD ($)				12 Months Ended
	Feb. 19, 2021	Feb. 04, 2021	Dec. 18, 2018	Dec. 31, 2022	Dec. 31, 2021
Vineti Inc [Member] \| Collaborative Arrangement [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transactions With Related Party Advisory Fees				$ 0	$ 400,000
Eden Biocell [Member]
Related Party Transaction [Line Items]
Payments to Fund Long-term Loans to Related Parties			$ 10,000,000.0
Additional Loans Committed			$ 25,000,000.0
Watermill And Robert W Postma [Member]
Related Party Transaction [Line Items]
Pocket Expenses		$ 400,000
Related party transaction, reimbursed amount	$ 400,000

Leases - Additional Information (Details)						1 Months Ended	12 Months Ended
Leases - Additional Information (Details)	Aug. 31, 2021	Dec. 15, 2020 USD ($)	Apr. 13, 2020	Oct. 15, 2019 USD ($) ft²	Mar. 12, 2019 USD ($) ft²	Jun. 30, 2012	Dec. 31, 2022 USD ($) ft²	Dec. 31, 2021 USD ($)	Apr. 07, 2020 USD ($) ft²
Operating Lease, Payments							$ 800,000
Operating Lease Impairment Loss								$ 600,000
Operating Lease Residual Value Of Leased Asset								1,400,000
Other Asset Impairment Charges								100,000
Discounted Risk-adjusted Rate							10.00%
Operating lease expiration month and year			2027-02	2027-02
Operating Leases Future Minimum Monthly Payment Due Through Years February 2027 and April 2028							$ 7,000
Right-of-use asset							2,136,000	4,420,000
Gain (Loss) On Modification Of Lease							100,000
Recognition in exchange of Operating Lease Liabilities							$ 0
Annual base rent increase							3.00%
Sublease Area \| ft²							4,772
Lease term, description							The term of the sub-sublease is from July 1, 2022 to June 30, 2025 and provides the sub-subtenant with an option to extend through to July 31, 2026.
Lease income from sublease, 2023							$ 200,000
Lease income from sublease, 2024							200,000
Lease income from sublease, 2025							100,000
Other Income Expense [Member]
Lease income							100,000
Boston, MA [Member]
Security Deposit							$ 100,000	$ 100,000
Sublease term amendment							Aug. 31, 2026
Operating lease expiration month and year	2026-08					2016-08
Houston, TX [Member]
Operating Lease Monthly Rental Payment					$ 2,000
Operating lease expiration month and year					2021-04
Operating Leases Future Minimum Monthly Payment Due Through Years February 2027 and April 2028		$ 37,000		$ 17,000					$ 12,000
Right-of-use asset							$ 400,000
Operating Lease Area \| ft²				8,443	1,038		3,228		5,594
Annual base rent increase		3.00%	3.00%	3.00%
Houston, TX [Member] \| Previously Reported [Member]
Operating Lease Area \| ft²							18,111

Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating lease cost	$ 756	$ 1,394
Total lease cost	$ 756	$ 1,394
Weighted-average remaining lease term (years)	4 years 1 month 17 days	5 years 6 months 29 days
Weighted-average discount rate	8.26%	8.00%

Leases - Operating Lease Liabilities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
2023	$ 757
2024	780
2025	804
2026	712
2027	158
Thereafter	31
Total lease payments	3,242
Less: imputed interest and adjustments	(496)
Present value of lease payments	$ 2,746
Operating lease liability statement of financial position [extensible list]	Present value of lease payments

Commitments and Contingencies - Additional Information (Detail) - USD ($)				3 Months Ended	12 Months Ended
	May 28, 2019	Aug. 17, 2015	Jan. 13, 2015	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 22, 2019	Feb. 19, 2019	Oct. 05, 2018	Aug. 24, 2004
Accrued Payments
Royalty amount					$ 0	$ 0
Research and development expense					25,018,000	49,643,000
Collaboration revenue					2,922,000	398,000
Md Anderson Warrant [Member]
Accrued Payments
Number of Warrants							3,333,333
Warrant exercise per share							$ 0.001
Warrant Expiry date							Dec. 31, 2026
MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Reimbursement of historical costs							$ 20,000,000.0
Payments due prior to the first marketing approval							3,000,000.0
Quarterly expense incurred					800,000	300,000
Aggregate potential benchmark payments							$ 36,500,000
CRADA Agreement [Member]
Accrued Payments
Contribution payable on per annum basis				$ 1,000,000.0
Obligations due under contract								$ 5,000,000.0
Annual expense incurred					0	1,300,000
Quarterly payments under contract					3,800,000
MD Anderson Agreement and Worldwide License [Member]
Accrued Payments
License agreement commencing date			Jan. 13, 2015
C A R Products [Member]
Accrued Payments
Maximum royalty amount									$ 100,000,000.0
The University of Texas MD Anderson Cancer Center and The Texas A & M University System [Member]
Accrued Payments
Milestone maximum payment										$ 4,500,000
One time milestone payment					2,500,000
Payment under license agreement						100,000
The University of Texas MD Anderson Cancer Center and The Texas A & M University System [Member] \| Royalty [Member]
Accrued Payments
Payment under license agreement					2,000	0
Collaboration Agreement with Solasia Pharma K.K. [Member]
Accrued Payments
Collaboration revenue					2,900,000	400,000
License Agreement with the National Cancer Institute [Member]
Accrued Payments
License Expense					700,000	$ 500,000
License Agreement with the National Cancer Institute [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
First benchmark payment					$ 100,000
Ziop License Agreement With The National Cancer Institute [Member]
Accrued Payments
Minimum royalties amount payable	$ 300,000
Aggregate minimum annual royalties paid	1,500,000
Royalties amount payable thereafter	$ 100,000
Description Of First Benchmark Payable	The first benchmark payment of $0.1 million was paid during the year ended December 31, 2022 upon the initiation of the Company's TCR-T Library Phase 1/2 Trial, which was a qualifying Phase 1 clinical trial under the terms of the Patent License.
Description Of option To terminate Agreement	The NCI may terminate or modify the Patent License in the event of a material breach, including if the Company does not meet certain milestones by certain dates, or upon certain insolvency events that remain uncured following the date that is 90 days following written notice of such breach or insolvency event.
Agreement termination, notice period	60 days
Ziop License Agreement With The National Cancer Institute [Member] \| Performance Based Payments [Member]
Accrued Payments
Aggregate Benchmark Payments Payable	$ 4,300,000
Ziop License Agreement With The National Cancer Institute [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
Potential Benchmark Payments Payable	12,000,000.0
Ziop License Agreement With The National Cancer Institute [Member] \| Post Marketing Approval [Member] \| Performance Based Payments [Member]
Accrued Payments
Aggregate Benchmark Payments Payable	3,000,000.0
Ziop License Agreement With The National Cancer Institute [Member] \| Licensed Products [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
Maximum Sales Revenue On Which Benchmark Payments Payable	1,000,000,000.0
Minimum sales revenue on which benchmark payments payable	$ 250,000,000.0
Intrexon Corporation [Member]
Accrued Payments
Annual License fee									100,000
Expected additional milestones payable									52,500,000
Intrexon Corporation [Member] \| T-Cell Receptor [Member]
Accrued Payments
Maximum royalty amount									$ 100,000,000.0
Portion of income payable to related party									20.00%
Minimum [Member] \| MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Research and development expense		$ 15,000,000.0
Maximum [Member] \| MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Research and development expense		$ 20,000,000.0

Warrants - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands						12 Months Ended
	Dec. 28, 2021	Aug. 06, 2021	Oct. 22, 2019	Sep. 12, 2019	Nov. 11, 2018	Dec. 31, 2022	Dec. 31, 2021
Fair Value Assumptions Expected volatility Rate Maximum						88.75%	74.80%
Fair Value Assumptions Risk Free Interest Rate Maximum						4.21%	1.36%
Aggregate offering price						$ 14,724
Proceeds from private placement				$ 52,500
Silicon Valley Bank Loan [Member]
Warrant Exercise Per share	$ 1.16	$ 2.22
Number of warrants issued		432,844
MD Anderson Warrant [Member]
Number of securities into which the class of warrant converted			3,333,333
Warrant Exercise Per share			$ 0.001
Fair Value of Warrants			$ 14,500
Warrant Expiry date			Dec. 31, 2026
Svb Warrants [Member]
Common stock		432,844
Exercise price		2.22
Warrants fully vested upon issuance		10 years
Black-Scholes Model [Member] \| Silicon Valley Bank Loan [Member]
Fair Value Assumptions Expected Term1	10 years
Exercise price	1.16
Expected volatility	81.00%
Risk-free interest rate	1.49%
Number of warrants issued	649,615
Dividends	$ 0
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]							Other Nonoperating Income (Expense)
Change in fair value							$ 200
Black-Scholes Model [Member] \| Svb Warrants [Member]
Fair Value of Warrants		$ 800
Fair Value Assumptions Expected Term1		10 years
Expected volatility		79.00%
Risk-free interest rate		1.31%
Dividends		$ 0
Securities Purchase Agreement [Member]
Aggregate offering price					$ 47,100
Private Placement [Member]
Number of securities into which the class of warrant converted				17,803,031	18,939,394
Warrant Exercise Per share				$ 3.01	$ 3.01
Fair Value Assumptions Expected volatility Rate Maximum					71.00%
Fair Value Assumptions Risk Free Interest Rate Maximum					2.99%
Fair Value Assumptions Expected Term1					5 years
Placement agent fees and other expenses				$ 1,100
Fair value of adjustment of warrants					$ 18,400
Dividends					$ 0
Private Placement [Member] \| New Warrants [Member]
Number of securities into which the class of warrant converted				17,803,031
Warrant Exercise Per share				$ 7.00
Non-cash inducement warrant expense				$ 60,800

Restructuring - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Severance costs		$ 3,657
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Severance costs	$ 0

Restructuring - Future termination benefit payments resulting from the strategic reduction in force (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)
Restructuring Cost and Reserve [Line Items]
Severance Costs	$ 3,657
Research and Development [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	2,368
General and Administrative [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	$ 1,289

Income Taxes - Significant Component of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Net operating loss carryforwards	$ 171,070	$ 164,486
Deferred tax assets:
Start-up and pre-clinical studies	17,204	21,705
Research and development credit carryforwards	40,116	39,817
Stock-based compensation	698	706
Capitalized acquisition costs	2,180	2,946
Lease liability	618	1,278
Depreciation	239	102
Capitalized research expenses	5,156	0
Other	27	156
Deferred Tax Assets Gross	237,308	231,196
Less valuation allowance	(236,827)	(230,119)
Total deferred tax assets	481	1,077
Deferred tax liabilities:
Right of use asset	(481)	(1,077)
Total deferred tax liabilities	(481)	(1,077)
Net deferred taxes	$ 0	$ 0

Income Taxes - Reconciliation of Income Tax Expense (Benefit) (Detail)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Federal income tax at statutory rates	21.00%	21.00%
State income tax, net of federal tax benefit	3.00%	3.00%
Research and development credits	2.00%	3.00%
Research and development true-up	(2.00%)	0.00%
Stock-based compensation	(1.00%)	(1.00%)
Federal/state rate change	(5.00%)	(2.00%)
Change in valuation allowance	(18.00%)	(24.00%)
Effective tax rate	0.00%	0.00%

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Income Taxes [Line Items]
Net operating loss carryforwards	$ 171,070	$ 164,486
Deferred tax assets operating loss carryforwards without expire date	323,800
Research and development credit carryforwards	40,116	39,817
Uncertain Tax Positions Adjustment	0	$ 0
Increase (decrease) in deferred tax assets	6,700
Domestic Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 665,500
Net operating loss carryforwards, expiration date	2037
Federal and State [Member]
Income Taxes [Line Items]
Deferred tax assets operating loss carryforwards with expire date	$ 341,700
Net operating loss carryforwards, expiration date	2042
Federal and State [Member] \| Research Tax Credit Carryforward
Income Taxes [Line Items]
Research and development credit carryforwards	$ 40,100
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 497,900

Preferred Stock and Stockholders' Equity (Deficit) - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Nov. 11, 2018	Dec. 31, 2022	Dec. 31, 2021
Equity [Line Items]
Common stock, shares authorized		420,000,000	350,000,000
Initial Public Offering of Common Stock		$ 0.001	$ 0.001
Aggregate offering price		$ 14,724
Common stock, shares outstanding		240,410,761	216,127,443
Common Stock [Member]
Equity [Line Items]
Common stock, shares authorized		420,000,000
Aggregate offering price		$ 24
Common stock, shares outstanding		240,410,761
Common Stock, shares reserved for future issuance		33,330,964
Securities Purchase Agreement [Member]
Equity [Line Items]
Aggregate offering price	$ 47,100

Stock Option Plan - Additional information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	May 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued	10,408,622	10,665,869	6,840,719
Proceeds from stock options exercised	$ 21	$ 1,036
Total intrinsic value of options	$ 26	$ 800
Options available for future grant	15,460,088
Restricted Stock [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award granted	280,000	1,601,224
Repurchase of Shares of Restricted Stock	18,750	0
Price per Share	$ 2.41
Unvested Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to non-vested restricted stock outstanding	$ 6,200
Expected recognition period	1 year 11 months 1 day
Unvested Restricted Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected recognition period	1 year 9 months 10 days
Share-based payment award granted	280,000	1,601,224
Unrecognized stock-based compensation expense related to non-vested restricted stock arrangements	$ 1,100
the "2012 Plan" [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance					14,000,000
Options available for future grant	1,066,275
the "2012 Plan" [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	1,089,296
the "2020 Plan" [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized				21,000,000
Options available for future grant				22,066,275
the "2020 Plan" [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	9,319,326

Stock Option Plan - Stock Option Activity Under Stock Option Plan (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Number of Shares
Beginning Balance	10,665,869	6,840,719
Granted	4,697,500	9,380,438
Exercised	(26,250)	(363,109)
Cancelled	(4,928,497)	(5,192,179)
Ending Balance	10,408,622	10,665,869
Options exercisable, at end of period	3,891,598	4,410,312
Options available for future grant	15,460,088
Weighted Average Exercise Price
Beginning Balance	$ 2.87	$ 3.81
Granted	1.08	2.62
Exercised	0.80	2.86
Cancelled	3.34	3.65
Ending Balance	1.84	2.87
Options exercisable, at end of period	$ 2.46	$ 3.85
Weighted Average Contractual Term (Years)
Outstanding, at end of period	8 years 8 months 8 days
Options exercisable, at end of period	8 years 29 days	7 years 6 months 10 days
Aggregate Intrinsic Value
Outstanding, at end of period	$ 3
Options exercisable, at end of period	$ 0	$ 0

Stock Option Plan - Summary of Non-Vested Restricted Stock (Detail) - Unvested Restricted Common Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Number of Shares
Beginning Balance	1,198,580	786,280
Granted	280,000	1,601,224
Vested	(306,617)	(754,137)
Cancelled	(232,901)	(434,787)
Ending Balance	939,062	1,198,580
Weighted Average Grant Date Fair Value
Beginning Balance	$ 2.10	$ 3.08
Granted	0.82	2.60
Vested	2.28	3.40
Cancelled	3.15	3.45
Ending Balance	$ 1.40	$ 2.10

Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Defined benefit plan contributions by employer	$ 0.5	$ 0.7