0000950170-24-038868 | 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 that was historically involved in the development of 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 was working to leverage 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.

As of December 31, 2023, there were 16,012,522 shares of common stock outstanding and an additional 1,918,297 shares of common stock reserved for issuance pursuant to outstanding stock options and warrants.

On August 14, 2023, the Company announced a strategic reprioritization of its business and wind down of its TCR-T Library Phase 1/2 Trial. In connection with the reprioritization, the Company has significantly reduced its workforce and continues working to reduce costs in order to extend its cash runway. The Company continues to explore strategic alternatives, including, but not limited to, an acquisition, merger, reverse merger, sale of assets, strategic partnerships, capital raises or other transactions. The Company has engaged Cantor Fitzgerald & Co., or Cantor, to act as strategic advisor for this process.

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, 2023, the Company had approximately $6.1 million of cash and cash equivalents. The Company’s accumulated deficit at December 31, 2023 was approximately $915.8 million. Given its current development plans and cash management efforts, the Company anticipates cash resources will be sufficient to fund operations into the third quarter of 2024. The Company continues to explore strategic alternatives, including, but not limited to, an acquisition, merger, reverse merger, sale of assets, strategic partnerships, capital raises or other transactions. 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.

The Company has elected to make a reclassification in the presentation of the cash flow to show non-cash changes in right-of-use assets and lease liabilities related to modifications and terminations as non-cash for the year ended December 31, 2022 in order to conform presentation to the December 31, 2023 disclosures.

Restructuring - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)
Restructuring and Related Activities [Abstract]
Termination benefits	$ 1.3

Preferred Stock and Stockholders' Equity (Deficit) - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Nov. 11, 2018	Dec. 31, 2023	Dec. 31, 2022
Equity [Line Items]
Common stock, shares authorized		34,666,667	28,000,000
Initial Public Offering of Common Stock		$ 0.001	$ 0.001
Aggregate offering price		$ 92	$ 14,724
Common stock, shares outstanding		16,012,522	16,027,384
Common Stock [Member]
Equity [Line Items]
Aggregate offering price			$ 2
Common stock, shares outstanding		16,012,522
Common Stock, shares reserved for future issuance		1,918,297
Securities Purchase Agreement [Member]
Equity [Line Items]
Aggregate offering price	$ 47,100

Equity Method Investments and Joint Ventures [Abstract]

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

+ References + Details

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, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 5,744	$ 38,058
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	$ 5,744	$ 38,058

Debt (Tables)

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Schedule of Debt

There were no debt obligations outstanding at December 31, 2023. The carrying values of the Company's debt obligation at December 31, 2022 were as follows:


	December 31,
($ in thousands)	2022
Loan and Security Agreement	$	17,395
Unamortized discount on Loan and Security Agreement		(630	)
Total debt		16,765
Less: long-term debt, current		(16,765	)
Long-term debt	$	—

Property and Equipment, net - Component of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 15	$ 18,267
Less: accumulated depreciation	(13)	(9,807)
Property and equipment, net	2	8,460
Office and computer equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	15	2,183
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	0	1,291
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	0	9,561
Laboratory equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 0	$ 5,232

Subsequent Events

12 Months Ended

Dec. 31, 2023

Subsequent Events [Abstract]

Subsequent Events

16.

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. Other than as described in the notes to the financial statements, the Company did not have any material subsequent events that impacted its financial statements or disclosures aside from the following.

On January 20, 2024, the Board of Directors appointed Dale Curtis Hogue, Jr. as Interim Chief Executive Officer of the Company, effective immediately. On January 21, 2024, the Company entered into an employment agreement with Mr. Hogue, under which he will receive an annual base salary of $250 thousand. Mr. Hogue was awarded 40,000 shares of common stock of the Company with an exercise price of $1.80.

On February 15, 2024, Michael Wong gave notice of his resignation as Vice President, Finance, effective February 23, 2024. On February 22, 2024, the Company and Ferdinand Groenewald entered into a consulting agreement, or the Consulting Agreement, effective February 22, 2024, pursuant to which Mr. Groenewald will lead accounting and financial reporting activities of the Company. Mr. Groenewald will serve as the Company’s Vice President, Finance. The Consulting Agreement will continue indefinitely until terminated by either party upon 30 days’ advance notice. The Consulting Agreement provides for compensation at a fixed rate of $15 thousand per month and reimbursement by the Company for any usual and customary business expenses incurred by Mr. Groenewald in connection with performing services pursuant to the Consulting Agreement. In addition, the Consulting Agreement provides for the Company to indemnify Mr. Groenewald on terms customary for officers.

Financings

12 Months Ended

Dec. 31, 2023

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 an amendment to the Loan and Security Agreement, or the First Amendment. The First Amendment extended the interest-only period through August 31, 2022. The First Amendment 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 was to mature on August 1, 2023. On May 1, 2023, the Company repaid its outstanding debt obligations under the amended Loan and Security Agreement in their entirety.

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

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 years ended December 31, 2023 and 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 1,615,248 shares, or the Firm Shares, of the Company’s common stock to the Underwriter at a price of $9.2865 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 242,287 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 14,420 shares of common stock.

Summary of Significant Accounting Policies - Potential Dilutive Shares Excluded from Computation of Diluted Net Loss Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	1,918,297	2,284,669
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	1,452,399	1,528,156
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	465,898	693,909
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	0	62,604

Income Taxes - Reconciliation of Income Tax Expense (Benefit) (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Federal income tax at statutory rates	21.00%	21.00%
State income tax, net of federal tax benefit	(92.00%)	3.00%
Research and development credits	2.00%	2.00%
Research and development true-up	(1.00%)	(2.00%)
Stock-based compensation	0.00%	(1.00%)
Federal/state rate change	(3.00%)	(5.00%)
Change in valuation allowance	73.00%	(18.00%)
Effective tax rate	0.00%	0.00%

Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 18, 2018	Dec. 31, 2023
Eden Biocell [Member]
Related Party Transaction [Line Items]
Payments to Fund Long-term Loans to Related Parties	$ 10,000
Additional Loans Committed	$ 25,000
Dune Lake Capital [Member]
Related Party Transaction [Line Items]
Consulting service amount		$ 37

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
Net operating loss carryforwards	$ 148,009	$ 171,070
Deferred tax assets operating loss carryforwards without expire date	363,200
Research and development credit carryforwards	39,838	40,116
Reduced credits carryforward	0
Uncertain Tax Positions Adjustment	0	$ 0
Increase (decrease) in deferred tax assets	(25,800)
Domestic Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 704,900
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	2043
Federal and State [Member] \| Research Tax Credit Carryforward
Income Taxes [Line Items]
Research and development credit carryforwards	$ 39,800
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	497,900
Increase (decrease) in deferred tax assets	$ 0

Joint Venture

12 Months Ended

Dec. 31, 2023

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 was 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 accounted for the equity interest in Eden BioCell under the equity method of accounting as it had the ability to exercise significant influence.

In September 2021, TriArm and the Company mutually agreed to dissolve the joint venture, which has now been terminated. The Eden BioCell entity has been dissolved as of July 2023.

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (35,140)	$ (37,730)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1A

Reference 37: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1B

Reference 38: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 39: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

Accrued Expenses - Component of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Clinical	$ 568	$ 2,200
Employee compensation	43	1,160
Professional services	717	534
Preclinical services	0	198
Manufacturing services	12	1,177
Other consulting services	0	16
Other	0	169
Total	$ 1,340	$ 5,454

Stock Option Plan - Summary of Non-Vested Restricted Stock (Detail) - Unvested Restricted Common Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Shares
Beginning Balance	62,604	79,905
Granted		18,667
Vested	(33,322)	(20,441)
Cancelled	(29,282)	(15,527)
Ending Balance	0	62,604
Weighted Average Grant Date Fair Value
Beginning Balance	$ 21.04	$ 31.54
Granted		12.3
Vested	17.94	34.21
Cancelled	24.6	47.23
Ending Balance	$ 0	$ 21.04

Stock Option Plan - Additional information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jun. 30, 2020	May 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued	465,898	693,909	711,058
Proceeds from stock options exercised	$ 0	$ 21,000
Total intrinsic value of options		$ 26,000
Options available for future grant	1,302,411
Restricted Stock [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award granted	0	18,667
Repurchase of Shares of Restricted Stock	0	1,250
Price per Share		$ 36.15
Unvested Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to non-vested restricted stock outstanding	$ 400,000
Expected recognition period	1 year 6 months 10 days
Unvested Restricted Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award granted		18,667
Unrecognized stock-based compensation expense related to non-vested restricted stock arrangements	$ 0
the "2012 Plan" [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance					933,333
Options available for future grant	71,085
the "2012 Plan" [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	65,728
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				1,400,000
Options available for future grant				1,471,085
the "2020 Plan" [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	400,167

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

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:

•

Clinical trial expenses and other research and development expenses;

•

Collaboration agreements;

•

Fair value measurements of stock-based compensation; and

•

Income taxes.

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.

•

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

•

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.

•

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, 2023 and 2022 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2023		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	5,744	$	5,744	$	—	$	—


($ 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	$	—	$	—

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, 2023 and 2022. The Company had no financial assets or liabilities that were classified as Level 2 or Level 3 during the years ended December 31, 2023 and 2022.

Fair value of non-financial instruments

The Company evaluates 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.

Following the Company’s announced strategic reprioritization on August 14, 2023, the Company determined that changes in the intended use of certain property and equipment represented an indicator of impairment, resulting in an impairment charge of $4.8 million, which was primarily related to leasehold improvements of $3.8 million and lab equipment of $1.0 million.

In addition, the Company determined certain prepaid expense balances to be impaired given the Company’s strategic reprioritization, and therefore, has recorded an impairment charge of $0.2 million related to prepaid expenses and other current assets, which is recorded in research and development expenses within the statement of operations.

On November 9, 2023, the Company executed an agreement to sell laboratory equipment for gross proceeds of $1.5 million and recognized a gain on disposal of equipment of $3 thousand, which is recorded in other income in the statement of operations.

Revenue Recognition from Collaboration Agreements

Revenue for the year ended December 31, 2023 consisted of $5 thousand and for the year ended December 31, 2022 consisted of $2.9 million. For the years ended December 31, 2023 and 2022, 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 and third-party vendors 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:

•

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.

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.

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, 2023 and 2022 and did not capitalize any such costs on the balance sheets. The Company recognized $2.5 million of compensation expense related to stock options for the year ended December 31, 2023 and $3.0 million of compensation expense related to stock options for the year ended December 31, 2022. The Company recognized $0.3 million of compensation expense related to restricted stock for the year ended December 31, 2023 and $0.5 million for the year ended December 31, 2022 (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, 2023 was $2.8 million

and $3.5 million for the year ended December 31, 2022. The following table presents share-based compensation expense included in the Company’s statements of operations:


	Year Ended December 31,
(in thousands)	2023		2022
Research and development		439		868
General and administrative		2,361		2,660
Stock-based compensation expense	$	2,800	$	3,528

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, 2023 was approximately $5.58 per share and was approximately $11.54 per share for the year ended December 31, 2022. 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,
	2023	2022
Risk-free interest rate	3.51 – 4.01%	1.63 – 4.21%
Expected life in years	5.06 – 6.25	5.27 – 6.25
Expected volatility	89.69 – 112.12%	74.49 – 88.75%
Expected dividend yield	—%	—%

Reverse Stock Split

On January 31, 2024, the Company filed a Second Amended and Restated Certificate of Incorporation (the “Charter Amendment”) with the Secretary of State of the State of Delaware in order to effect a reverse stock split of the Company’s common stock at a ratio of 1-for-15 (the “Reverse Split”). The Charter Amendment decreased the number of authorized shares of common stock from 520,000,000 to 34,666,667. The Charter Amendment does not affect the par value of the Company’s common stock or change the number of authorized shares or par value of the Company’s preferred stock. The Charter Amendment became effective on January 31, 2024 at 5:00 p.m. Eastern Time, at which time every 15 shares of the Company’s issued and outstanding common stock automatically combined and converted into 1 share of common stock.

No fractional shares were issued in connection with the Reverse Split. Stockholders of record who would otherwise have been entitled to receive fractional shares as a result of the Reverse Split received a cash payment in lieu thereof at a price equal to the fraction to which the stockholder would otherwise be entitled multiplied by the closing sales price per share of the common stock (as adjusted for the Reverse Split) on The Nasdaq Capital Market on January 31, 2024.

All share and per share amounts of common stock, options, warrants, and restricted stock in the accompanying financial statements and notes thereto have been retroactively adjusted for all periods presented to reflect the Reverse Split as if it had occurred at the beginning of the earliest period presented.

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,
	2023			2022
Net loss	$	(35,140	)	$	(37,730	)
Weighted-average common shares outstanding, basic and diluted		15,995,323			14,475,354
Net loss per share, basic and diluted	$	(2.20	)	$	(2.61	)

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, 2023 and 2022 as the result would be antidilutive. Such potential common shares on December 31, 2023 and 2022 consist of the following:


	December 31,
	2023		2022
Common stock options		465,898		693,909
Unvested restricted stock		-		62,604
Warrants		1,452,399		1,528,156
		1,918,297		2,284,669

New Accounting Pronouncements

In June 2016, the FASB issued Accounting Standards Update, or ASU, 2016-13, Financial Instruments: Credit Losses (Topic 326) as clarified in ASU 2019-04, ASU 2019-05 and ASU 2020-02. The objective of this standard is to provide information about expected credit losses on financial instruments at each reporting date and to change how other-than-temporary impairments on investment securities are recorded. The Company adopted ASU 2016-13 effective January 1, 2023, with no material impact upon adoption.

In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which enhances the disclosures required for operating segments in the Company's annual and interim financial statements. ASU 2023-07 is effective retrospectively for fiscal years beginning after December 15, 2023 and for interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company is currently evaluating the impact of this standard.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which is intended to enhance the transparency and decision usefulness of income tax disclosures. The amendments in ASU 2023-09 provide for enhanced income tax information primarily through changes to the rate reconciliation and income taxes paid information. ASU 2023-09 is effective for the Company prospectively to all annual periods beginning after December 15, 2024. Early adoption is permitted. The Company is currently evaluating the impact of this standard.

Financings - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended
	Jan. 05, 2023	Nov. 29, 2022	Aug. 12, 2022	Dec. 31, 2023	Dec. 31, 2022	Aug. 06, 2021
Debt Instrument [Line Items]
Aggregate offering price				$ 92	$ 14,724
At The Market Offering [Member]
Debt Instrument [Line Items]
Number of additional option available to the underwriter to purchase		242,287
Term A Tranche [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Loan and Security Agreement						$ 25,000
Term B Tranche [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Additonal tranche facility						$ 25,000
Equity Distribution Agreement [Member]
Debt Instrument [Line Items]
Stock issued during period				0	0
Aggregate offering price			$ 50,000
Percentage Of Commission On Gross Proceeds From Sale Of Common Stock			3.00%
Cantor [Member]
Debt Instrument [Line Items]
Common stock issuance		1,615,248
Underwriter par or stated value per share		$ 9.2865
Threshold period for exercise or conversion of stock		30 days
Cantor [Member] \| Stock Option [Member]
Debt Instrument [Line Items]
Stock issued during period	14,420
Sale of stock consideration received on transaction		$ 14,700

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Significant Component of Deferred Tax Assets

Significant components of the Company’s deferred tax assets at December 31, 2023 and 2022 are as follows:


	December 31,
(in thousands)	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	148,009		$	171,070
Start-up and pre-clinical studies		13,754			17,204
Research and development credit carryforwards		39,838			40,116
Stock-based compensation		681			698
Capitalized acquisition costs		1,570			2,180
Lease liability		—			618
Depreciation		1			239
Capitalized research expenses		7,176			5,156
Other		2			27
		211,031			237,308
Less valuation allowance		(211,031	)		(236,827	)
Total deferred tax assets		—			481

Right-of-use asset		—			(481	)
Total deferred tax liabilities	$	—		$	(481	)
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)	2023			2022
Federal income tax at statutory rates		21	%		21	%
State income tax, net of federal tax benefit		(92	)%		3	%
Research and development credits		2	%		2	%
Research and development true-up		(1	)%		(2	)%
Stock-based compensation	—%				(1	)%
Federal/state rate change		(3	)%		(5	)%
Change in valuation allowance		73	%		(18	)%
Effective tax rate		—	%		—	%

Leases - Additional Information (Details)			12 Months Ended
Leases - Additional Information (Details)	Nov. 15, 2023 USD ($)	Apr. 19, 2023	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Nov. 01, 2023 ft²	Aug. 31, 2023 USD ($) ft²	Jun. 30, 2022 ft²	Apr. 30, 2022 USD ($) ft²
Lease termination date			Apr. 19, 2023
Sublease term amendment		Jul. 31, 2026
Termination costs			$ 200,000
Gain on lease termination			298,000	$ 133,000
Operating Lease Area \| ft²					14,037
Right-of-use assets			0	2,136,000
Gain (Loss) On Modification Of Lease				100,000
Sublease Area \| ft²							4,772
Lease term, description		a term expiring on June 30, 2025 with an option to extend through July 31, 2026
Operating Lease, Payments	$ 100,000		400,000
Recognition in exchange of Operating Lease Liabilities			0
Leases other than short-term lease			0
MD Anderson [Member]
Gain on lease termination			100,000
Other Income Expense [Member]
Lease income			43,000	$ 100,000
Boston, MA [Member]
Gain on lease termination			$ 200,000
Houston, TX [Member]
Operating Lease Area \| ft²						3,228		3,228
Right-of-use assets						$ 19,000		$ 400,000
Houston, TX [Member] \| Previously Reported [Member]
Operating Lease Area \| ft²								18,111

Organization - Additional Information (Detail) - USD ($) $ in Thousands	Aug. 14, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Strategic advisor name	Cantor
Cash, cash equivalents and restricted cash		$ 6,062	$ 52,996	$ 76,054
Accumulated deficit		$ (915,767)	$ (880,627)
Common stock, shares outstanding		16,012,522	16,027,384
Common Stock [Member]
Common stock, shares outstanding		16,012,522
Common stock reserved for future issuance		1,918,297

Commitments and Contingencies Disclosure [Abstract]

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies

Exclusive License Agreement with Precigen

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. Except where the context otherwise requires, the Company refers to PGEN and Precigen together as Precigen. Pursuant to the terms of the License Agreement, the Company had 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 the Company, Precigen and ARES TRADING S.A., a subsidiary of Merck KGaA, as assigned by Precigen to PGEN. Under the License Agreement, the Company also had 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 was responsible for all aspects of the research, development and commercialization and was required to use commercially reasonable efforts to develop certain products.

In consideration of the licenses and other rights granted by Precigen, the Company was required to pay Precigen an annual license fee of $0.1 million, reimburse Precigen for certain historical costs, pay Precigen milestones up to an additional $52.5 million for each exclusively licensed program upon the achievement of certain milestones, and pay Precigen tiered royalties up to a maximum royalty amount of $100.0 million in the aggregate. The Company was also obligated to pay Precigen 20% of any sublicensing income received relating to the licensed products. The Company was responsible for all development costs associated with each of the licensed products. For the years ended December 31, 2023 and 2022, the Company paid $0.1 million in annual license fees under this agreement.

Precigen was obligated to pay the Company royalties up to a maximum royalty amount of $100.0 million. No royalty amounts were incurred during the years ended December 31, 2023 and 2022.

On April 3, 2023, the Company entered into the Amended and Restated Exclusive License Agreement with Precigen, or the A&R License Agreement, which restated and amended the License Agreement in full. Under the A&R License Agreement, the Company still has exclusive, worldwide rights to research, develop and commercialize TCR products designed for neoantigens or driver mutations for the treatment of cancer and non-exclusive rights to use non-driver mutation TCRs. The Company further maintains its 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 remains solely responsible for all aspects of the research, development and commercialization of the exclusively licensed products for the treatment of cancer. The (i) products utilizing Precigen’s RheoSwitch® gene switch, or RTS, for the treatment of cancer, referred to as IL-12 Products and (ii) 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 the Company, Precigen and ARES TRADING S.A., a subsidiary of Merck KGaA, as assigned by Precigen to PGEN are no longer exclusively licensed to the Company. The Company is no longer obligated to use commercially reasonable efforts for the exclusively licensed products. The A&R License Agreement further eliminates any royalty or milestone obligations to Precigen, with an annual license fee of $75 thousand due on the anniversary of the A&R License Agreement effective date. Precigen is no longer obligated to pay the Company royalties on the net sales derived from the sale of Precigen's CAR 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 a license agreement, or the MD Anderson License with MD Anderson (which Precigen subsequently assigned to PGEN). Pursuant to the MD Anderson License, the Company, together with Precigen, 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.

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 the Company entered into on October 22, 2019, with MD Anderson, pursuant to which the Company agreed to collaborate with respect to the TCR program. For the year ended December 31, 2023 the Company incurred clinical expenses of $0.1 million from MD Anderson related to the 2015 R&D Agreement, and did not incur clinical costs from MD Anderson related to the 2015 R&D Agreement for the year ended December 31, 2022.

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, Precigen, 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 years ended December 31, 2023 and 2022, the Company incurred clinical expenses of $0.8 million from MD Anderson related to the 2019 R&D Agreement.

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 222,222 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 $0.015 per share, expires on December 31, 2026, and vests upon the occurrence of certain clinical milestones. As of December 31, 2023, 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 held 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 held 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 required the Company to pay the NCI minimum annual royalties in the amount of $0.3 million, which amount would be reduced to $0.1 million once the aggregate minimum annual royalties paid by the Company equaled $1.5 million.

The Company was 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 were $4.3 million, of which aggregate payments of $3.0 million would be 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 was 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 was $12.0 million. The Company was also required to 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 entered into a sublicensing agreement relating to a licensed product, the Company would be required to pay the NCI a percentage of all consideration received from a sublicensee, which percentage would decrease based on the stage of development of the licensed product at the time of the sublicense.

The Patent License was to expire upon expiration of the last patent contained in the licensed patent rights, unless terminated earlier. The NCI could terminate or modify the Patent License in the event of a material breach, including if the Company did 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 could 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 had 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 was not reasonably satisfying required health and safety needs and (ii) terminate or modify the Patent License, including if the Company was not satisfying requirements for public use as specified by federal regulations. On October 27, 2023, the Company provided the NCI the requisite notice of its intent to terminate the Patent

License, effective December 26, 2023. The Company discovered multiple proprietary TCRs targeting driver mutations through its hunTR TCR discovery platform, including many of the same KRAS and TP53 mutations licensed from the NCI.

For the year ended December 31, 2023 the Company incurred $0.4 million of expenses and incurred $0.7 million of expenses for the year ended December 31, 2022.

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 was under 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 was 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 would have remained the sole property of the party who produced the discovery. The parties would have jointly owned all inventions jointly discovered under the research plan. The owner of any invention under the CRADA would have made the decision to file a patent covering the invention, or in the case of a jointly owned invention, the Company would have the first opportunity to file a patent covering the invention. If the Company failed to provide timely notice of its decision to the NCI or decided not to file a patent covering the joint invention, the NCI had 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 granted 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 were 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 was 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 could be terminated by any of the parties upon 60 days' prior written consent.

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. In March 2022, the Company entered into an amendment to the CRADA that is 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 recorded expenses of $0.5 million for the year ended December 31, 2023, compared to $0 for the year ended December 31, 2022.

On August 14, 2023, the Company announced that it had provided the requisite notice to terminate the CRADA, pursuant to its terms, effective October 13, 2023, in light of the Company’s exploration of strategic alternatives.

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, 2023, the Company did not incur any milestone expenses under this agreement, and the Company incurred $1 thousand in royalty expenses on sales under this agreement during the year ended December 31, 2023. During the year ended December 31, 2022, $2.5 million was incurred as a one-time milestone payment under

the terms of the agreement, and the Company incurred $2 thousand in royalty expenses on sales under this agreement during the year ended December 31, 2022.

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, 2023, the Company did not earn collaboration revenue and earned $5 thousand in royalty revenues on net sales under the Solasia License and Collaboration Agreement. 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, and did not earn royalty revenues on net sales under the agreement.

KBI Biopharma Litigation

On March 17, 2023, KBI Biopharma, Inc., or KBI, filed a complaint against the Company in the District Court of Harris County, Texas, 165th Judicial District, asserting breach of an Amended and Restated Master Services Agreement between the Company and KBI relating to the development of an autologous gene modified T-cell therapy product, or the KBI Agreement. KBI was primarily seeking unspecified monetary damages in excess of $3.2 million. On May 1, 2023, the Company filed an answer generally denying all of KBI’s allegations and asserting affirmative and other defenses as well as counterclaims for breach of the KBI Agreement and conversion. On October 20, 2023, the Company entered into an agreement with KBI to settle all claims asserted by KBI against the Company and the Company's counterclaims against KBI at issue in the litigation for $1.0 million.

Joint Venture - Additional Information (Details)	Jul. 05, 2019
Ziopharm [Member] \| Eden Bio Cell [Member]
Subsidiary or Equity Method Investee [Line Items]
Equity interest in affilated entity	50.00%

STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2021	$ 58,057	$ 14	$ 900,895	$ (842,852)
Balance (in shares) at Dec. 31, 2021		14,408,496
Stock-based compensation	3,528		3,528
Restricted stock awards (in shares)		18,667
Exercise of employee stock options	$ 21		21
Exercise of employee stock options (in shares)	1,750	1,750
Repurchase of common stock	$ (45)			(45)
Repurchase of common stock (in shares)		(1,250)
Issuance of common stock, net of expenses	14,724	$ 2	14,722
Issuance of common stock, net of expenses (in shares)		1,615,248
Cancelled restricted common stock (in shares)		(15,527)
Net loss	(37,730)			(37,730)
Balance at Dec. 31, 2022	38,555	$ 16	919,166	(880,627)
Balance (in shares) at Dec. 31, 2022		16,027,384
Stock-based compensation	2,800		2,800
Issuance of common stock, net of expenses	92		92
Issuance of common stock, net of expenses (in shares)		14,420
Cancelled restricted common stock (in shares)		(29,282)
Net loss	(35,140)			(35,140)
Balance at Dec. 31, 2023	$ 6,307	$ 16	$ 922,058	$ (915,767)
Balance (in shares) at Dec. 31, 2023		16,012,522

Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Retirement Benefits [Abstract]
Defined benefit plan contributions by employer	$ 0.2	$ 0.5

Debt - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Dec. 28, 2021	Aug. 06, 2021	Dec. 31, 2023	Dec. 31, 2022
Line of Credit Facility [Line Items]
Debt obligations			$ 0	$ 0
Line of credit facility, interest rate		4.50%
Interest expense			$ 1,900	$ 3,200
Term Loan [Member]
Line of Credit Facility [Line Items]
Percentage of original principal due as a final payment		5.75%
Line of credit facility, interest rate		7.75%
Silicon Valley Bank Loan [Member]
Line of Credit Facility [Line Items]
Warrants issued	43,308
Warrants expiration date	Aug. 06, 2031
Description of payment terms		the Company also owed SVB 5.75% of the original principal amounts borrowed as a final payment, or the Final Payment. Effective March 30, 2023, the Company entered into a Third Amendment to the Loan and Security Agreement, or the Third Amendment. Under the terms of the Third Amendment, the Company was no longer required to maintain all of its operating accounts, depository accounts and excess cash with SVB or one of its affiliates, and was instead only required to maintain a single operating or depository account at Silicon Valley Bank. The Third Amendment also modified the cash collateralization requirement, such that the Company was required to cash collateralize the entire sum of the outstanding principal amount of the SVB Facility, plus an amount equal to the Final Payment, which amount was to be reduced commensurate with each regularly scheduled monthly payment of principal and interest on the SVB Facility.On May 1, 2023, the Company paid SVB an amount equal to the entire outstanding principal amount under the SVB Facility, all accrued and unpaid interest and the Final Payment. In accordance with the First Amendment, the payment was subject to a prepayment premium of 2.00%.
Debt instrument description of variable rate basis			The SVB Facility bore 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%.
Extinguishment of debt, amount			$ 500
Amount of prepayments premium			$ 100
Number of warrants issued		28,856
Warrant exercise per share	$ 17.4	$ 33.3
Additional number warrants issued		28,856
Debt instrument, initial maturity date			Aug. 01, 2023
Silicon Valley Bank Loan [Member] \| Debt Instrument Redemption Period One
Line of Credit Facility [Line Items]
Percentage of prepayments premium			2.00%
Silicon Valley Bank Loan [Member] \| Warrants [Member]
Line of Credit Facility [Line Items]
Issuance costs	$ 1,200

Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases, Operating [Abstract]

Components of Lease Expense

The components of lease expense were as follows:


	Year Ended December 31,
($ in thousands)	2023		2022
Operating lease cost	$	428	$	756
Total lease cost	$	428	$	756
Weighted-average remaining lease term (years)		—		4.13
Weighted-average discount rate		—		8.26	%

Property and Equipment, net (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Component of Property and Equipment, Net

Property and equipment, net, consists of the following:


	December 31,
($ in thousands)	2023			2022
Office and computer equipment	$	15		$	2,183
Software		-			1,291
Leasehold improvements		-			9,561
Laboratory equipment		-			5,232
		15			18,267
Less: accumulated depreciation		(13	)		(9,807	)
Property and equipment, net	$	2		$	8,460

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Subsequent Events - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Feb. 22, 2024	Jan. 21, 2024	Dec. 31, 2023	Dec. 31, 2022
Subsequent Event [Line Items]
Stock options granted exercise price			$ 7.35	$ 16.14
Notice period	30 days
Subsequent Event [Member]
Subsequent Event [Line Items]
Consulting Agreement Provides for Compensation	$ 15
Subsequent Event [Member] \| Mr. Hogue
Subsequent Event [Line Items]
Annual salary in cash		$ 250
Common stock shares awarded		40,000
Stock options granted exercise price		$ 1.8

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Component of Accrued Expenses

Accrued expenses consist of the following:


($ in thousands)	2023		2022
Clinical	$	568	$	2,200
Employee compensation		43		1,160
Professional services		717		534
Preclinical services		-		198
Manufacturing services		12		1,177
Other consulting services		-		16
Other		-		169
	$	1,340	$	5,454

Stock Option Plan

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

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 933,333 shares for issuance. On December 31, 2023, there were 65,728 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 1,400,000 shares for issuance plus a carryover of 71,085 shares from the 2012 Plan for a total of 1,471,085 shares. In addition, returning shares from the 2012 Plan are available for issuance under the 2020 Plan. As of December 31, 2023, there were 400,167 shares reserved for issuance and 1,302,411 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.

There were no proceeds from option exercises during the year ended December 31, 2023 as compared to $21 thousand during the year ended December 31, 2022. The intrinsic value of these options amounted to $26 thousand for the year ended December 31, 2022.

Stock option activity under the Company's stock options plans for the years ending December 31, 2023 and 2022 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, 2021		711,058		$	43.05
Granted		313,167			16.14
Exercised		(1,750	)		12.00
Cancelled		(328,566	)		50.10
Outstanding, December 31, 2022		693,909		$	27.60
Granted		259,122			7.35
Cancelled		(487,133	)		17.70
Outstanding, December 31, 2023		465,898		$	26.85		7.81	$	—
Options exercisable, December 31, 2023		415,376		$	28.80		7.64	$	—
Options available for future grant, December 31, 2023		1,302,411

On December 31, 2023, total unrecognized compensation costs related to non-vested stock options outstanding amounted to $0.4 million, which is expected to be recognized over a weighted-average period of 1.53 years.

Restricted Stock

For the year ended December 31, 2023 the Company did not issue shares of restricted stock and issued 18,667 in the year ended December 31, 2022 to directors. There were no repurchases by the Company for the year ended December 31, 2023. During the year ended December 31, 2022, the Company repurchased 1,250 shares at a price of $36.15 per share to cover payroll taxes for one employee exercise, which is in accordance with the original terms of the award.

A summary of the status of restricted stock as of December 31, 2023 and 2022 is as follows:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested, December 31, 2021		79,905		$	31.54
Granted		18,667			12.30
Vested		(20,441	)		34.21
Cancelled		(15,527	)		47.23
Unvested, December 31, 2022		62,604		$	21.04
Vested		(33,322	)		17.94
Cancelled		(29,282	)		24.60
Unvested, December 31, 2023		—		$	—

As of December 31, 2023, there was no unrecognized stock-based compensation expense related to non-vested restricted stock arrangements.

Income Taxes

12 Months Ended

Dec. 31, 2023

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, 2023 and 2022 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, 2023 and 2022 are as follows:


	December 31,
(in thousands)	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	148,009		$	171,070
Start-up and pre-clinical studies		13,754			17,204
Research and development credit carryforwards		39,838			40,116
Stock-based compensation		681			698
Capitalized acquisition costs		1,570			2,180
Lease liability		—			618
Depreciation		1			239
Capitalized research expenses		7,176			5,156
Other		2			27
		211,031			237,308
Less valuation allowance		(211,031	)		(236,827	)
Total deferred tax assets		—			481

Right-of-use asset		—			(481	)
Total deferred tax liabilities	$	—		$	(481	)
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, 2023, the Company has aggregate net operating loss carryforwards for federal tax purposes of approximately $704.9 million, of which approximately $341.7 million expire at various dates through December 31, 2037 and approximately $363.2 million can be carried forward indefinitely. The Company is reducing its approximately $497.9 million of state net operating loss carryforwards to $0 as these state net operating loss carryforwards all related to Massachusetts filings and, as of December 31, 2023 the Company no longer had any employees or property in Massachusetts and, as a result, the Company will no longer have income tax nexus in Massachusetts or an income tax filing obligation after the year ended December 31, 2023. Additionally, the Company has approximately $39.8 million of federal and state research and development credits at December 31, 2023, expiring in varying amounts through 2043, which may be available to reduce future taxes. The Company has reduced its Massachusetts credits carryforward to $0.

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 decreased by $25.8 million in 2023 due primarily to the reduction of Massachusetts net operating loss carryforwards and Massachusetts 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)	2023			2022
Federal income tax at statutory rates		21	%		21	%
State income tax, net of federal tax benefit		(92	)%		3	%
Research and development credits		2	%		2	%
Research and development true-up		(1	)%		(2	)%
Stock-based compensation	—%				(1	)%
Federal/state rate change		(3	)%		(5	)%
Change in valuation allowance		73	%		(18	)%
Effective tax rate		—	%		—	%

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, 2023 and 2022.

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 2023 to the extent net operating losses continue to be carried forward to 2023.

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.

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Cover Page - USD ($)	12 Months Ended
Cover Page - USD ($)	Dec. 31, 2023	Mar. 27, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Entity Registrant Name	Alaunos Therapeutics, Inc.
Entity Central Index Key	0001107421
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Trading Symbol	TCRT
Document Transition Report	false
Document Annual Report	true
Security Exchange Name	NASDAQ
Title of 12(b) Security	Common Stock
Entity File Number	001-33038
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	2617 Bissonnet Street,
Entity Address, Address Line Two	Suite 225
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77005
Entity Tax Identification Number	84-1475642
City Area Code	346
Local Phone Number	355-4099
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Document Financial Statement Error Correction [Flag]	false
ICFR Auditor Attestation Flag	false
Entity Common Stock, Shares Outstanding		16,012,479
Entity Public Float			$ 94,764,946
Auditor Name	RSM US LLP
Auditor Location	Boston, MA
Auditor Firm ID	49

Summary of Significant Accounting Policies - Earning Per share Basic and Diluted (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Net loss	$ (35,140)	$ (37,730)
Weighted average common shares outstanding, basic	15,995,323	14,475,354
Weighted average common shares outstanding, diluted	15,995,323	14,475,354
Net loss per share, basic	$ (2.2)	$ (2.61)
Net loss per share, diluted	$ (2.2)	$ (2.61)

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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	34,666,667	28,000,000
Common stock, shares issued	16,012,522	16,027,384
Common stock, shares outstanding	16,012,522	16,027,384

Property and Equipment, net - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Aug. 14, 2023	Dec. 31, 2023	Dec. 31, 2022
Depreciation		$ 2,315	$ 2,759
Asset Impairment Charges		4,803	$ 0
Leasehold improvements [Member]
Asset Impairment Charges	$ 3,800	$ 4,800

STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Collaboration revenue	$ 5	$ 2,922
Operating expenses:
Research and development	16,279	25,018
General and administrative	12,219	13,142
Gain on lease modification and termination	(298)	(133)
Restructuring costs	1,269	0
Property and equipment and right-of-use assets impairment	4,803	0
Total operating expenses	34,272	38,027
Loss from operations	(34,267)	(35,105)
Other income (expense):
Interest expense	(1,921)	(3,154)
Other income , net	1,048	529
Other income (expense), net	(873)	(2,625)
Net loss	$ (35,140)	$ (37,730)
Earnings per share, Basic	$ (2.2)	$ (2.61)
Earnings per share, Diluted	$ (2.2)	$ (2.61)
Weighted average common shares outstanding, basic	15,995,323	14,475,354
Weighted average common shares outstanding, diluted	15,995,323	14,475,354

Warrants - Additional Information (Details) - 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, 2023	Dec. 31, 2022
Fair Value Assumptions Expected volatility Rate Maximum						112.12%	88.75%
Fair Value Assumptions Risk Free Interest Rate Maximum						4.01%	4.21%
Aggregate offering price						$ 92	$ 14,724
Proceeds from private placement				$ 52,500
Silicon Valley Bank Loan [Member]
Warrant exercise per share	$ 17.4	$ 33.3
Number of warrants issued		28,856
MD Anderson Warrant [Member]
Number of securities into which the class of warrant converted			222,222
Warrant exercise per share			$ 0.015
Fair value of warrants			$ 14,500
Warrant Expiry date			Dec. 31, 2026
SVB Warrants [Member]
Common stock		28,856
Exercise price		33.30
Warrants exercised						0
Warrants fully vested upon issuance		10 years
Black-Scholes Model [Member] \| Silicon Valley Bank Loan [Member]
Exercise price	17.40
Number of warrants issued	43,308
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				1,186,869	1,262,626
Warrant exercise per share				$ 45.15	$ 45.15
Fair value of warrants					$ 18,400
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
Dividends					$ 0
Private Placement [Member] \| New Warrants [Member]
Number of securities into which the class of warrant converted				1,186,869
Warrant exercise per share				$ 105
Non-cash inducement warrant expense				$ 60,800

Debt

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Debt

4. Debt

There were no debt obligations outstanding at December 31, 2023. The carrying values of the Company's debt obligation at December 31, 2022 were as follows:


	December 31,
($ in thousands)	2022
Loan and Security Agreement	$	17,395
Unamortized discount on Loan and Security Agreement		(630	)
Total debt		16,765
Less: long-term debt, current		(16,765	)
Long-term debt	$	—

On August 6, 2021, the Company entered into the Loan and Security Agreement with SVB. The Loan and Security Agreement provided for the funding of the Term A Tranche at the closing, with the Term B Tranche available if certain funding and clinical milestones were met by August 31, 2022. The SVB Facility and related obligations under the Loan and Security Agreement were secured by substantially all of the Company's

properties, rights and assets, except for its intellectual property (which was subject to a negative pledge under the Loan and Security Agreement). In addition, the Loan and Security Agreement contained customary representations, warranties, events of default and covenants.

On December 28, 2021, the Company entered into the First Amendment to the Loan and Security Agreement. The First Amendment eliminated the unfunded Term B Tranche, among other things. The SVB Facility bore 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%.

All outstanding obligations under the amended Loan and Security Agreement were due and payable on August 1, 2023. In connection with the payment of all of the Company's outstanding obligations, the Company also owed SVB 5.75% of the original principal amounts borrowed as a final payment, or the Final Payment. Effective March 30, 2023, the Company entered into a Third Amendment to the Loan and Security Agreement, or the Third Amendment. Under the terms of the Third Amendment, the Company was no longer required to maintain all of its operating accounts, depository accounts and excess cash with SVB or one of its affiliates, and was instead only required to maintain a single operating or depository account at Silicon Valley Bank. The Third Amendment also modified the cash collateralization requirement, such that the Company was required to cash collateralize the entire sum of the outstanding principal amount of the SVB Facility, plus an amount equal to the Final Payment, which amount was to be reduced commensurate with each regularly scheduled monthly payment of principal and interest on the SVB Facility.

On May 1, 2023, the Company paid SVB an amount equal to the entire outstanding principal amount under the SVB Facility, all accrued and unpaid interest and the Final Payment. In accordance with the First Amendment, the payment was subject to a prepayment premium of 2.00%. During the year ended December 31, 2023, the Company recorded the remaining amounts associated with the Final Payment of $0.5 million and the prepayment premium of $0.1 million as interest expense within the statement of operations.

In connection with its entry into the Loan and Security Agreement in August 2021, the Company issued to SVB warrants to purchase (i) up to 28,856 shares of the Company’s common stock, in the aggregate, and (ii) up to an additional 28,856 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 $33.30.

In connection with its entry into the First Amendment in December 2021, the Company amended and restated the warrants issued to SVB. As amended and restated, the warrants are for up to 43,308 shares of the Company's common stock, in the aggregate, with an exercise price of $17.40 per share, or the SVB Warrants. The SVB Warrants expire on August 6, 2031.

The issuance costs for the Loan and Security Agreement, including the First Amendment, were approximately $1.2 million and primarily related to the SVB Warrants, which were amortized into interest expense over the term of the loan. Interest expense, including the amortization of issuance costs, was $1.9 million for the year ended December 31, 2023 and $3.2 million for the year ended December 31, 2022.

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Income Taxes - Significant Component of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Net operating loss carryforwards	$ 148,009	$ 171,070
Deferred tax assets:
Start-up and pre-clinical studies	13,754	17,204
Research and development credit carryforwards	39,838	40,116
Stock-based compensation	681	698
Capitalized acquisition costs	1,570	2,180
Lease liability	0	618
Depreciation	1	239
Capitalized research expenses	7,176	5,156
Other	2	27
Deferred Tax Assets Gross	211,031	237,308
Less valuation allowance	(211,031)	(236,827)
Total deferred tax assets	0	481
Deferred tax liabilities:
Right of use asset	0	(481)
Total deferred tax liabilities	0	(481)
Net deferred taxes	$ 0	$ 0

Leases

12 Months Ended

Dec. 31, 2023

Leases, Operating [Abstract]

Leases

In April 2022, the Company modified its real estate lease agreement executed on December 15, 2020 with MD Anderson for office space in Houston, Texas, 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.

In June 2022, the Company executed an agreement to sub-sublease 4,772 square feet of subleased office space in Boston. For the year ended December 31, 2023, the Company recognized $43 thousand in lease income, and for the year ended December 31, 2022, the Company recognized $0.1 million in lease income. Lease income is classified within other income on the statement of operations.

On April 19, 2023, the Company terminated its office lease in Boston, Massachusetts, which was set to expire on August 31, 2026. In connection with the termination, the Company also assigned to the landlord its sub-sublease of the Boston office space, which had a term expiring on June 30, 2025 with an option to extend through July 31, 2026. Termination costs for the Boston office lease were $0.2 million. A gain of $0.2 million was recorded on the lease termination during the year ended December 31, 2023.

In August 2023, in accordance with the lease agreement executed on December 15, 2020, the Company notified MD Anderson, as landlord, of its intention to terminate office space of 3,228 square feet in Houston, Texas. As a result, the associated lease liability and right-of-use asset were remeasured to $19 thousand, reflecting the revised lease payments and term end date of November 2023.

On November 1, 2023, the Company and MD Anderson, as landlord, agreed to mutually terminate the leases dated October 15, 2019 and April 7, 2020, which represented office space totaling 14,037 square feet, effective November 15, 2023. As a result, the Company agreed to make a final payment of $0.1 million to the landlord. A gain of $0.1 million was recorded on the lease termination during the year ended December 31, 2023.

The components of lease expense were as follows:


	Year Ended December 31,
($ in thousands)	2023		2022
Operating lease cost	$	428	$	756
Total lease cost	$	428	$	756
Weighted-average remaining lease term (years)		—		4.13
Weighted-average discount rate		—		8.26	%

The Company paid $0.4 million in operating lease costs for the year-ended December 31, 2023. The Company did not recognize new operating lease assets obtained in exchange for operating lease liabilities for the year-ended December 31, 2023. The Company did not have any leases, other than a short-term lease, as of December 31, 2023.

Stock Option Plan - Stock Option Activity Under Stock Option Plan (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Shares
Beginning Balance	693,909	711,058
Granted	259,122	313,167
Exercised		(1,750)
Cancelled	(487,133)	(328,566)
Ending Balance	465,898	693,909
Options exercisable, at end of period	415,376
Options available for future grant	1,302,411
Weighted Average Exercise Price
Beginning Balance	$ 27.6	$ 43.05
Granted	7.35	16.14
Exercised		12
Cancelled	17.7	50.1
Ending Balance	26.85	$ 27.6
Options exercisable, at end of period	$ 28.8
Weighted Average Contractual Term (Years)
Outstanding, at end of period	7 years 9 months 21 days
Options exercisable, at end of period	7 years 7 months 20 days
Aggregate Intrinsic Value
Outstanding, at end of period	$ 0
Options exercisable, at end of period	$ 0

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

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, 2023 and 2022 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2023		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	5,744	$	5,744	$	—	$	—


($ 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	$	—	$	—

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)	2023		2022
Research and development		439		868
General and administrative		2,361		2,660
Stock-based compensation expense	$	2,800	$	3,528

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,
	2023	2022
Risk-free interest rate	3.51 – 4.01%	1.63 – 4.21%
Expected life in years	5.06 – 6.25	5.27 – 6.25
Expected volatility	89.69 – 112.12%	74.49 – 88.75%
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,
	2023			2022
Net loss	$	(35,140	)	$	(37,730	)
Weighted-average common shares outstanding, basic and diluted		15,995,323			14,475,354
Net loss per share, basic and diluted	$	(2.20	)	$	(2.61	)

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

Such potential common shares on December 31, 2023 and 2022 consist of the following:


	December 31,
	2023		2022
Common stock options		465,898		693,909
Unvested restricted stock		-		62,604
Warrants		1,452,399		1,528,156
		1,918,297		2,284,669

Summary of Significant Accounting Policies - Stock-Based Compensation Expense Included in Statement of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 2,800	$ 3,528
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	439	868
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 2,361	$ 2,660

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-URI https://asc.fasb.org//1943274/2147480483/718-10-35-1D

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Property, Plant and Equipment [Abstract]

Property and Equipment, net

12 Months Ended

Dec. 31, 2023

Property and Equipment, net

Property and equipment, net, consists of the following:


	December 31,
($ in thousands)	2023			2022
Office and computer equipment	$	15		$	2,183
Software		-			1,291
Leasehold improvements		-			9,561
Laboratory equipment		-			5,232
		15			18,267
Less: accumulated depreciation		(13	)		(9,807	)
Property and equipment, net	$	2		$	8,460

Depreciation expense for the year ended December 31, 2023 was $2.3 million and was $2.8 million for the year ended December 31, 2022. During the year ended December 31, 2023, the Company impaired property and equipment by $4.8 million. Refer to Note 3, Summary of Significant Accounting Policies, for further details.

Accrued Expenses

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Accrued Expenses

Accrued expenses consist of the following:


($ in thousands)	2023		2022
Clinical	$	568	$	2,200
Employee compensation		43		1,160
Professional services		717		534
Preclinical services		-		198
Manufacturing services		12		1,177
Other consulting services		-		16
Other		-		169
	$	1,340	$	5,454

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2023
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 $0.2 million to the 401(k) Plan during the year ended December 31, 2023 and $0.5 million during the year ended December 31, 2022.

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands							12 Months Ended
	Oct. 20, 2023	Aug. 14, 2023	Mar. 17, 2023	May 28, 2019	Aug. 17, 2015	Jan. 13, 2015	Dec. 31, 2023	Dec. 31, 2022	Apr. 03, 2023	Oct. 22, 2019	Feb. 19, 2019	Oct. 05, 2018	Aug. 24, 2004
Accrued Payments
Research and development expense							$ 16,279	$ 25,018
Royalty amount							0	0
Maximum royalty amount												$ 100,000
Collaboration revenue							5	2,922
Unspecified monetary damages			$ 3,200
Loss contingency, name of plaintiff			KBI Biopharma
Litigation expense	$ 1,000
Md Anderson Warrant [Member]
Accrued Payments
Number of Warrants										222,222
Warrant exercise per share										$ 0.015
Warrant Expiry date										Dec. 31, 2026
MD Anderson Related to the 2015 R&D Agreement [Member]
Accrued Payments
Clinical expenses							100	0
MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Reimbursement of historical costs										$ 20,000
Clinical expenses							800	800
Aggregate potential benchmark payments										36,500
Payments due prior to the first marketing approval										$ 3,000
CRADA Agreement [Member]
Accrued Payments
Agreement termination date		Oct. 13, 2023
Contribution payable on per annum basis							1,000
Obligations due under contract											$ 5,000
Annual expense incurred							500	0
MD Anderson Agreement and Worldwide License [Member]
Accrued Payments
License agreement commencing date						Jan. 13, 2015
The University of Texas MD Anderson Cancer Center and The Texas A & M University System [Member]
Accrued Payments
Milestone maximum payment													$ 4,500
One time milestone payment								2,500
The University of Texas MD Anderson Cancer Center and The Texas A & M University System [Member] \| Royalty [Member]
Accrued Payments
Payment under license agreement							1	2
License Agreement with the National Cancer Institute [Member]
Accrued Payments
License Expense							400	700
License Agreement with the National Cancer Institute [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
First benchmark payment				$ 100
Ziop License Agreement With The National Cancer Institute [Member]
Accrued Payments
Minimum royalties amount payable				300
Royalties amount payable thereafter				100
Aggregate minimum annual royalties paid				$ 1,500
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 could terminate or modify the Patent License in the event of a material breach, including if the Company did 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
Ziop License Agreement With The National Cancer Institute [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
Potential Benchmark Payments Payable				12,000
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
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
Minimum sales revenue on which benchmark payments payable				$ 250,000
Collaboration Agreement with Solasia Pharma K.K. [Member]
Accrued Payments
Collaboration revenue							0	2,900
Collaboration Agreement with Solasia Pharma K.K. [Member] \| Royalty [Member]
Accrued Payments
Collaboration revenue							5
Intrexon Corporation [Member]
Accrued Payments
Annual License fee							$ 100	$ 100	$ 75			100
Expected additional milestones payable												52,500
Intrexon Corporation [Member] \| T-Cell Receptor [Member]
Accrued Payments
Maximum royalty amount												$ 100,000
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
Maximum [Member] \| MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Research and development expense					$ 20,000

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

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.

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, 2023 and 2022 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2023		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	5,744	$	5,744	$	—	$	—


($ 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	$	—	$	—

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

and $3.5 million for the year ended December 31, 2022. The following table presents share-based compensation expense included in the Company’s statements of operations:


	Year Ended December 31,
(in thousands)	2023		2022
Research and development		439		868
General and administrative		2,361		2,660
Stock-based compensation expense	$	2,800	$	3,528


	Year Ended December 31,
	2023	2022
Risk-free interest rate	3.51 – 4.01%	1.63 – 4.21%
Expected life in years	5.06 – 6.25	5.27 – 6.25
Expected volatility	89.69 – 112.12%	74.49 – 88.75%
Expected dividend yield	—%	—%

Reverse Stock Split

Net Loss per Share

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


	Year Ended December 31,
	2023			2022
Net loss	$	(35,140	)	$	(37,730	)
Weighted-average common shares outstanding, basic and diluted		15,995,323			14,475,354
Net loss per share, basic and diluted	$	(2.20	)	$	(2.61	)


	December 31,
	2023		2022
Common stock options		465,898		693,909
Unvested restricted stock		-		62,604
Warrants		1,452,399		1,528,156
		1,918,297		2,284,669

New Accounting Pronouncements

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Total debt		$ 16,765
Less: long-term debt, current	$ 0	(16,765)
Long-term debt	$ 0	0
Silicon Valley Bank Loan [Member]
Debt Instrument [Line Items]
Loan and Security Agreement		17,395
Unamortized discount on Loan and Security Agreement		$ (630)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Related Party Transactions

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended
	Jan. 31, 2024	Nov. 09, 2023	Aug. 14, 2023	Dec. 31, 2023	Dec. 31, 2022
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses				$ 2,800	$ 3,528
Pre stock split shares authorized	520,000,000
Post Stock Split Shares Authorized	34,666,667
Weighted average fair value of stock option granted				$ 5.58	$ 11.54
Stockholders equity reverse stock split	The Charter Amendment became effective on January 31, 2024 at 5:00 p.m. Eastern Time, at which time every 15 shares of the Company’s issued and outstanding common stock automatically combined and converted into 1 share of common stock.
Fixed asset impairment charges			$ 4,800
Asset Impairment Charges				$ 4,803	$ 0
Proceeds from the disposal of property and equipment				1,543	23
Gain on disposal of equipment				(7)	(7)
Collaboration revenue				$ 5	2,922
Prepaid Expenses and Other Current Assets
Summary Of Significant Accounting Policies [Line Items]
Asset Impairment Charges			200
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
Asset Impairment Charges			1,000
Proceeds from the disposal of property and equipment		$ 1,500
Gain on disposal of equipment		$ 3
Leasehold improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Asset Impairment Charges			$ 3,800	$ 4,800
Property and equipment estimated useful life, Description [Extensible Enumeration]				us-gaap:UsefulLifeTermOfLeaseMember
Employee Stock Option
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses				$ 2,500	3,000
Restricted Stock [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses				300	500
Stock Options and Restricted Stock [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses				$ 2,800	$ 3,500

Summary of Significant Accounting Policies - Fair Value of Stock Options Assumptions Using Black-Scholes Option Valuation Model (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Risk-free interest rate, Minimum	3.51%	1.63%
Risk-free interest rate, Maximum	4.01%	4.21%
Expected volatility, Minimum	89.69%	74.49%
Expected volatility, Maximum	112.12%	88.75%
Maximum [Member]
Expected life in years	6 years 3 months	6 years 3 months
Minimum [Member]
Expected life in years	5 years 21 days	5 years 3 months 7 days

Related Party Transactions

12 Months Ended

Dec. 31, 2023

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 contributed $10.0 million to Eden BioCell and has committed up to an additional $25.0 million to this joint venture. TriArm also managed 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 was the Chair of the Company's board of directors until September 22, 2023 and had been a director since July 2020. He also serves as a member of Eden BioCell’s board of directors.

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 has been dissolved as of July 2023. Refer to Note 15, Joint Venture, for further details.

Collaboration with Dune Lake Capital

In January 2023, the Company entered into a consulting agreement with Dune Lake Capital, LLC, or Dune Lake Capital, which was founded by Dale Curtis Hogue, Jr., the Company's interim Chief Executive Officer. During the year ended December 31, 2023, the Company recorded expenses of approximately $37 thousand for consulting services performed by Dune Lake Capital with respect to the period from January 2023 to August 2023.

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

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