0000950170-22-024695 | 10-Q | XBRL Viewer

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Cover Page - shares	9 Months Ended
Cover Page - shares	Sep. 30, 2022	Nov. 09, 2022
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Document Quarterly Report	true
Document Transition Report	false
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
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Common Stock, Shares Outstanding		216,182,042
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-33038
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	84-1475642
Entity Address, Address Line One	8030 El Rio Street
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77054
City Area Code	346
Local Phone Number	355-4099

BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 37,807	$ 76,054
Restricted cash	13,938	0
Receivables	2,911	1,111
Prepaid expenses and other current assets	849	1,666
Total current assets	55,505	78,831
Property and equipment, net	9,050	10,941
Right of use asset	2,247	4,420
Deposits	42	42
Other non-current assets	500	631
Total assets	67,344	94,865
Current liabilities:
Accounts payable	1,984	1,368
Current portion of long-term debt	22,668	7,868
Accrued expenses	7,675	6,076
Lease liability, current	542	729
Total current liabilities	32,869	16,041
Long-term debt	0	16,250
Lease liability, non-current	2,334	4,518
Other non-current liabilities	28	0
Total liabilities	35,231	36,809
Commitments and contingencies (Note 9)
Stockholders' equity
Common stock $0.001 par value; 420,000,000 shares authorized, 216,182,042 shares issued and outstanding at September 30, 2022 and 350,000,000 shares authorized, 216,127,443 shares issued and outstanding at December 31, 2021	216	216
Additional paid-in capital	903,365	900,693
Accumulated deficit	(871,468)	(842,852)
Total stockholders' equity	32,113	58,057
Total liabilities and stockholders' equity	$ 67,344	$ 94,865

BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	420,000,000	350,000,000
Common stock, shares issued	216,182,042	216,127,443
Common stock, shares outstanding	216,182,042	216,127,443

STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Collaboration revenue	$ 2,911	$ 398	$ 2,911	$ 398
Operating expenses:
Research and development	7,893	14,521	19,411	41,427
General and administrative	3,282	8,173	10,217	25,469
Gain on lease modification	0	0	(133)	0
Total operating expenses	11,175	22,694	29,495	66,896
Loss from operations	(8,264)	(22,296)	(26,584)	(66,498)
Other income (expense):
Interest Expense	(841)	(444)	(2,266)	(444)
Other income (expense), net	254	7	279	(15)
Other income (expense), net	(587)	(437)	(1,987)	(459)
Net loss	$ (8,851)	$ (22,733)	$ (28,571)	$ (66,957)
Earnings per share, Basic	$ (0.04)	$ (0.11)	$ (0.13)	$ (0.31)
Earnings per share, Diluted	$ (0.04)	$ (0.11)	$ (0.13)	$ (0.31)
Weighted Average Number Of Shares Outstanding Basic	215,098,995	214,542,465	215,015,377	214,310,349
Weighted Average Number Of Diluted Shares Outstanding	215,098,995	214,542,465	215,015,377	214,310,349

STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid In Capital	Accumulated Deficit
Balance at Dec. 31, 2020	$ 123,982	$ 215	$ 887,868	$ (764,101)
Balance (in shares) at Dec. 31, 2020		214,591,906
Stock-based compensation	9,857		9,857
Exercise of employee stock options	1,037		1,037
Exercise of employee stock options (in shares)		363,109
Restricted stock awards		$ 1	(1)
Restricted stock awards (in shares)		1,601,224
Cancelled restricted common stock (in shares)		(410,435)
Issuance of warrants	788		788
Net loss	(66,957)			(66,957)
Balance at Sep. 30, 2021	68,707	$ 216	899,549	(831,058)
Balance (in shares) at Sep. 30, 2021		216,145,804
Balance at Jun. 30, 2021	88,281	$ 216	896,390	(808,325)
Balance (in shares) at Jun. 30, 2021		215,559,148
Stock-based compensation	2,371		2,371
Restricted stock awards (in shares)		875,000
Cancelled restricted common stock (in shares)		(288,344)
Issuance of warrants	788		788
Net loss	(22,733)			(22,733)
Balance at Sep. 30, 2021	68,707	$ 216	899,549	(831,058)
Balance (in shares) at Sep. 30, 2021		216,145,804
Balance at Dec. 31, 2021	58,057	$ 216	900,693	(842,852)
Balance (in shares) at Dec. 31, 2021		216,127,443
Stock-based compensation	2,651		2,651
Exercise of employee stock options	$ 21		21
Exercise of employee stock options (in shares)	26,250	26,250
Repurchase of common stock	$ (45)			(45)
Repurchase of common stock (in Shares)		(18,750)
Restricted stock awards (in shares)		280,000
Cancelled restricted common stock (in shares)		(232,901)
Net loss	(28,571)			(28,571)
Balance at Sep. 30, 2022	32,113	$ 216	903,365	(871,468)
Balance (in shares) at Sep. 30, 2022		216,182,042
Balance at Jun. 30, 2022	40,180	$ 216	902,536	(862,572)
Balance (in shares) at Jun. 30, 2022		216,174,542
Stock-based compensation	808		808
Exercise of employee stock options	21		21
Exercise of employee stock options (in shares)		26,250
Repurchase of common stock	(45)			(45)
Repurchase of common stock (in Shares)		(18,750)
Net loss	(8,851)			(8,851)
Balance at Sep. 30, 2022	$ 32,113	$ 216	$ 903,365	$ (871,468)
Balance (in shares) at Sep. 30, 2022		216,182,042

STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities:
Net loss	$ (28,571)	$ (66,957)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	2,065	1,892
Amortization of financing costs	634	148
Stock-based compensation	2,651	9,857
Decrease (increase) in the carrying amount of right-of-use assets	2,306	(529)
Gain on lease modification	(133)	0
(Increase) decrease in:
Receivables	(1,800)	3,155
Prepaid expenses and other current assets	817	7,646
Other non-current assets	131	508
Increase (decrease) in:
Accounts payable	616	503
Accrued expenses	1,525	(3,169)
Lease liabilities	(2,371)	604
Other non-current liabilities	28	0
Net cash used in operating activities	(22,102)	(46,342)
Cash flows from investing activities:
Purchases of property and equipment	(100)	(2,964)
Net cash used in investing activities	(100)	(2,964)
Cash flows from financing activities:
Proceeds from long-term debt borrowing	0	25,000
Debt issuance costs	0	(75)
Proceeds from the exercise of stock options	21	1,037
Repurchase of common stock	(45)	0
Repayment of long-term debt	(2,083)	0
Net cash provided by (used in) financing activities	(2,107)	25,962
Net decrease in cash, cash equivalents and restricted cash	(24,309)	(23,344)
Cash, cash equivalents and restricted cash, beginning of period	76,054	115,069
Cash, cash equivalents and restricted cash, end of period	51,745	91,725
Supplementary disclosure of cash flow information:
Cash paid for interest	1,603	136
Amounts included in accrued expenses and accounts payable related to property and equipment	$ 74	$ 348

Organization

9 Months Ended

Sep. 30, 2022

Accounting Policies [Abstract]

Organization

Overview

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

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

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 ("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.

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 September 30, 2022, the Company had approximately $37.8 million of cash and cash equivalents and $13.9 million of restricted cash related to the Company's debt agreement (see Note 4). The Company’s accumulated deficit at September 30, 2022 was approximately $871.5 million. Given its current development plans and cash management efforts, the Company anticipates cash resources will be sufficient to fund operations into the second quarter of 2023. The Company’s ability to continue operations after its current cash resources are exhausted depends on its ability to obtain additional financing, as to which no assurances can be given. Cash requirements may vary materially from those now planned because of changes in the Company’s focus and direction of its research and development programs, competitive and technical advances, patent developments, regulatory changes or other developments. If adequate additional funds are not available when required, management may need to curtail its development efforts and planned operations to conserve cash.

Based on the current cash forecast, 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, which raises substantial doubt as to the Company's ability to continue as a going concern. 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.

As of September 30, 2022, there were 216,182,042 shares of common stock outstanding and an additional 33,545,557 shares of common stock reserved for issuance pursuant to outstanding stock options and warrants.

Basis of Presentation

The accompanying unaudited interim financial statements have been prepared in accordance with the instructions to Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission, or the SEC. Certain information and note disclosures required by generally accepted accounting principles in the United States, or GAAP, have been condensed or omitted pursuant to such rules and regulations.

It is management’s opinion that the accompanying unaudited interim financial statements reflect all adjustments (which are normal and recurring) that are necessary for a fair presentation of the financial position of the Company and its results of operations and cash flows for the periods presented. The unaudited interim financial statements should be read in conjunction with the audited financial statements and the notes thereto for the year ended December 31, 2021, included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 filed with the SEC on March 30, 2022, or the Annual Report.

The results disclosed in the statements of operations for the three and nine months ended September 30, 2022 are not necessarily indicative of the results to be expected for the full fiscal year 2022.

Use of Estimates

The preparation of financial statements in conformity with 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 revenues 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.

Financings

9 Months Ended

Sep. 30, 2022

Text Block [Abstract]

Financings

2021 Loan and Security Agreement

On August 6, 2021, the Company entered into a Loan and Security Agreement (the "Loan and Security Agreement") with Silicon Valley Bank and affiliates of Silicon Valley Bank (collectively, "SVB"). The Loan and Security Agreement provided for an initial term loan of $25.0 million funded at the closing (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 (the "Term B Tranche").

Effective December 28, 2021, the Company, entered into a First Amendment (the “Amendment”) to the Loan and Security Agreement (as so amended, the "Amended Loan and Security Agreement").

The Amended Loan and Security Agreement extended the interest-only period through August 31, 2022. The Amended Milestones (as defined below) were not met by the Company on or prior to August 31, 2022, and therefore, the interest-only period was not extended beyond August 31, 2022. The Amendment also eliminated the Term B Tranche, which remained unfunded, leaving only the Term A Tranche (the "SVB Facility"). Under the Amended Loan and Security Agreement, the SVB Facility will mature on August 1, 2023.

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

2022 Equity Distribution Agreement

On August 12, 2022, the Company entered into an Equity Distribution Agreement (the "Equity Distribution Agreement") with Piper Sandler & Co. ("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 three and nine months ended September 30, 2022, there have been no sales of the Company's common stock under the Equity Distribution Agreement.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2022

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

The Company’s significant accounting policies were identified in the Company’s Annual Report. There have been no material changes in those policies since the filing of its Annual Report.

Debt

9 Months Ended

Sep. 30, 2022

Debt Disclosure [Abstract]

Debt

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


	September 30,			December 31,
($ in thousands)	2022			2021
Loan and Security Agreement	$	23,461		$	25,209
Unamortized discount on Loan and Security Agreement		(793	)		(1,091	)
Total debt	$	22,668		$	24,118

As of September 30, 2022, the SVB Facility was fully drawn in the amount of $25.0 million. The SVB Facility bears interest at a floating rate per annum on outstanding loans, payable monthly, at the greater of (a) 7.75% and (b) the current published U.S. prime rate, plus a margin of 4.5%. As of September 30, 2022, interest on the outstanding loans was 10.75%. The Amended Loan and Security Agreement provided for an interest-only period through August 31, 2022. On or prior to August 31, 2022, the Company had not (i) received at least $50.0 million in net cash proceeds from the sale of the Company’s equity securities after the date of the Amended Loan and Security Agreement, on terms acceptable to SVB, nor (ii) achieved positive data in the first cohort of the Library TCR-T Trial endorsed by an independent safety monitoring committee as a safe dose to proceed (together, the “Amended Milestones”), and, therefore, the interest-only period was not extended beyond August 31, 2022. Commencing on September 1, 2022, aggregate outstanding borrowings are payable in twelve consecutive, equal monthly installments of principal plus accrued interest.

All outstanding obligations under the Amended Loan and Security Agreement are due and payable on August 1, 2023. The Company will also owe SVB 5.75% of the original principal amounts borrowed as a final payment (the "Final Payment"). The Company is

permitted to make up to two prepayments, subject to a prepayment premium of the amount being prepaid, ranging from 1.00% to 2.00%, of the SVB Facility, each such prepayment to be at least $5.0 million plus all accrued and unpaid interest on the portion being prepaid.

As a result of not achieving the Amended Milestones on or prior to August 31, 2022, the Amended Loan and Security Agreement required the Company to cash collateralize half of the sum of the then-outstanding principal amount of the SVB Facility, plus an amount equal to 5.75% of the original principal amount of the SVB Facility. As of September 30, 2022, the Company has collateralized $13.9 million, which is classified as restricted cash on the balance sheet. So long as no event of default has occurred and subject to certain other terms related to the remaining outstanding balance under the SVB Facility being satisfied, $2.5 million will be released from the collateral account following the eighth scheduled payment of principal and interest, and a further $4.0 million will be released following the tenth scheduled payment of principal and interest. The SVB Facility and related obligations under the Amended Loan and Security Agreement are secured by substantially all of the Company’s properties, rights and assets, except for its intellectual property (which is subject to a negative pledge under the Amended Loan and Security Agreement). In addition, the Amended Loan and Security Agreement contains customary representations, warranties, events of default and covenants.

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

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

The issuance costs for the Loan and Security Agreement, including the Amended Loan and Security Agreement, were approximately $1.2 million and primarily related to the SVB Warrants, which will be amortized into interest expense over the period to August 1, 2023. Interest expense was $0.8 million for the three months ended September 30, 2022 and was $2.3 million for the nine months ended September 30, 2022, compared to $0.4 million for the three and nine months ended September 30, 2021.

The fair value of the Amended Loan and Security Agreement as of September 30, 2022 approximates its face value.

- Definition

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

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+ Details

Fair Value Measurements

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

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 September 30, 2022 and December 31, 2021 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of September 30, 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	$	36,807	$	36,807	$	—	$	—


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

The cash equivalents represent demand deposit accounts and deposits in a short-term United States treasury money market mutual fund quoted in an active market and classified as a Level 1 asset.

There have been no changes to the valuation methods during the nine months ended September 30, 2022. We had no financial assets or liabilities that were classified as Level 2 or Level 3 during the nine months ended September 30, 2022.

Net Loss per Share

9 Months Ended

Sep. 30, 2022

Earnings Per Share [Abstract]

Net Loss per Share

Net loss per share

Basic net loss per share is computed by dividing net loss by the weighted average number of shares of common stock outstanding for the period. The Company’s potentially dilutive shares, which include outstanding common stock options, inducement stock options, unvested restricted stock and warrants, have not been included in the computation of diluted net loss per share for any of the periods presented as the result would be anti-dilutive. Such potentially dilutive shares of common stock consisted of the following as of September 30, 2022 and 2021, respectively:


	September 30,
	2022		2021
Common stock options		10,623,215		11,072,894
Inducement stock options		-		97,500
Unvested restricted stock		940,000		1,510,655
Warrants		22,922,342		22,705,571
		34,485,557		35,386,620

Related Party Transactions

9 Months Ended

Sep. 30, 2022

Related Party Transactions

Collaboration with Vineti Inc.

On July 9, 2020, the Company entered into a master service agreement and statement of work with Vineti, Inc. ("Vineti"). Pursuant to the agreement, Vineti has been developing a software platform to coordinate and orchestrate the order, cell collection and manufacturing process for the Company’s T-cell therapy, or TCR-T, clinical programs. Heidi Hagen, who became a director of the Company in June 2019 and resigned November 2, 2021 and the Company's Interim Chief Executive Officer on February 25, 2021 and resigned on August 30, 2021, is a co-founder and former officer of Vineti. During the three and nine months ended September 30, 2022, the Company recorded no expenses for Vineti, compared to $0.1 million of expenses for the three months ended September 30, 2021 and $0.4 million for the nine months ended September 30, 2021.

WaterMill Settlement Agreement

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

In accordance with the Settlement Agreement, the Company agreed to reimburse the WaterMill Parties for up to $0.4 million of their reasonable out-of-pocket expenses out of a total of approximately $0.7 million in fees and expenses actually incurred by the WaterMill Parties in connection with (i) the WaterMill Parties' solicitation of written consents from the Company's stockholders to vote in favor of certain proposals, as set forth in the definitive consent statement filed by the WaterMill Parties on October 30, 2020, and (ii) the negotiation, execution, and effectuation of the Settlement Agreement. As of February 19, 2021, the Company has fully reimbursed the WaterMill Parties an aggregate amount of $0.4 million.

Joint Venture with TriArm Therapeutics/Eden BioCell

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

partner of Panacea Venture, which is an investor in TriArm. Mr. Huang is the Chair of the Company's board of directors and has been a director since July 2020. He also serves as a member of Eden BioCell’s board of directors.

For the three and nine months ended September 30, 2022, Eden BioCell incurred a net loss and the Company continues to have no commitment to fund its operations. In September 2021, TriArm and Alaunos mutually agreed to dissolve the Eden BioCell joint venture. Refer to Note 12 - Joint Venture, for further details.

Commitments and Contingencies

9 Months Ended

Sep. 30, 2022

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

License Agreements

Exclusive License Agreement with PGEN Therapeutics

On October 5, 2018, the Company entered into an exclusive license agreement, or License Agreement, with PGEN Therapeutics, or PGEN, a wholly owned subsidiary of Precigen Inc., or Precigen, which was formerly known as Intrexon Corporation. Pursuant to the terms of the License Agreement, the Company has exclusive, worldwide rights to research, develop and commercialize (i) TCR products designed for neoantigens for the treatment of cancer, (ii) products utilizing Precigen’s RheoSwitch® gene switch, or RTS, for the treatment of cancer, referred to as IL-12 Products and (iii) CAR products directed to (A) CD19 for the treatment of cancer, referred to as CD19 Products, and (B) BCMA for the treatment of cancer, subject to certain obligations to pursue such target under the Ares Trading Agreement. Under the License Agreement, the Company also has exclusive, worldwide rights for certain patents relating to the Sleeping Beauty technology to research, develop and commercialize TCR products for both neoantigens and shared antigens for the treatment of cancer, referred to as TCR Products.

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

In consideration of the licenses and other rights granted by PGEN, the Company will pay PGEN an annual license fee of $0.1 million and the Company has agreed to reimburse PGEN for certain historical costs of the licensed programs up to $1.0 million, which was fully paid during the year ended December 31, 2019.

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

PGEN will pay the Company royalties ranging from low-single digits to mid-single digits on the net sales derived from the sale of PGEN’s CAR products, up to a maximum royalty amount of $100.0 million.

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

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

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

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

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

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

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

On October 22, 2019, the Company entered into the 2019 Research and Development Agreement, or the 2019 R&D Agreement, with MD Anderson, pursuant to which the parties agreed to collaborate with respect to the TCR program. Under the 2019 R&D Agreement, the parties 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 intellectual property 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 outside the field of oncology and to develop and commercialize TCR products manufactured using viral gene transfer technologies limited to autologous products if used for cancer treatment or prevention, and a non-exclusive license for allogenic anti-tumor 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 three months ended September 30, 2022, the Company incurred clinical expenses of $0.3 million from MD Anderson related to this agreement compared to $0 for the three months ended September 30, 2021. For the nine months ended September 30, 2022, the Company incurred clinical expenses of $0.7 million from MD Anderson related to this agreement compared to $0 for the nine months ended September 30, 2021.

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

In connection with the execution of the 2019 R&D Agreement, on October 22, 2019, the Company issued MD Anderson a warrant to purchase 3,333,333 shares of the Company's common stock, which is referred to as the MD Anderson Warrant. Please refer to Note 11 - Warrants, for further discussion of the MD Anderson Warrant. The MD Anderson Warrant has an initial exercise price of $0.001 per share, expires on December 31, 2026, and vests upon the occurrence of certain clinical milestones. As of September 30, 2022, the milestones have not been met.

License Agreement with the NCI

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

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

The Company is also required to make performance-based payments upon successful completion of clinical and regulatory benchmarks relating to the licensed products. Of such payments, the aggregate potential benchmark payments are $4.3 million, of which aggregate payments of $3.0 million are due only after marketing approval in the United States or in Europe, Japan, Australia, China or India. The first benchmark payment of $0.1 million was due upon the initiation of the Company's first sponsored Phase 1 clinical trial of a licensed product or licensed process in the field of use licensed under the Patent License. The Company paid the first benchmark payment during the nine months ended September 30, 2022.

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

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

For the three months ended September 30, 2022, the Company recognized $0.1 million in license payments to the NCI under this agreement, compared to $0.3 million for the three months ended September 30, 2021. For the nine months ended September 30, 2022,

the Company recognized $0.5 million in license payments to the NCI under this agreement, compared to $0.6 million for the nine months ended September 30, 2021.

Cooperative Research and Development Agreement (CRADA) with the NCI

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

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

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

In February 2019, the Company extended the CRADA with the NCI until January 9, 2022, committing an additional $5.0 million to this program. 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 (the "CRADA Fourth Amendment") which, among other things, extended the term of the CRADA until January 9, 2025. In connection with the CRADA Fourth Amendment, the Company agreed to contribute $1.0 million per year, payable on a quarterly basis, beginning in the first quarter of 2023. The Company did not record expenses under the CRADA for the three and nine months ended September 30, 2022, as compared to $0 for the three months ended September 30, 2021 and $1.3 million for the nine months ended September 30, 2021.

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

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

Under the terms of the agreement, the Company may be required to make additional payments to the Licensors upon achievement of certain milestones in varying amounts which, on a cumulative basis could total up to an additional $4.5 million. In addition, the Licensors are entitled to receive royalty payments on sales from a licensed product and will also be entitled to receive a portion of any fees that the Company may receive from a possible sublicense under certain circumstances. During the three and nine months ended September 30, 2022, $2.5 million was expensed as a one-time milestone payment under the terms of the agreement, compared to $0.1 million for the three and nine months ended September 30, 2021. During the three and nine months ended September 30, 2022 and 2021, the Company did not incur royalty expenses on sales under this agreement.

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. ("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 (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 three and nine months ended September 30, 2022, the Company recorded $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. During the three and nine months ended September 30, 2021, the Company recorded $0.4 million of collaboration revenue under the Solasia License and Collaboration Agreement. During the three and nine months ended September 30, 2022 and 2021, the Company did not record royalty revenues on net sales of darinaparsin under this agreement.

Leases

9 Months Ended

Sep. 30, 2022

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, 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 nine months ended September 30, 2022.

In June 2022, the Company executed an agreement to sub-sublease 4,772 square feet of subleased office space in Boston. The term of the sub-sublease is from July 1, 2022 to June 30, 2025 and provides the sub-subtenant with an option to extend through to July 31, 2026. For the three and nine months ended September 30, 2022, the Company recognized $44 thousand in lease income, which is classified within other income (expense), net in the statement of operations.

Stock-Based Compensation

9 Months Ended

Sep. 30, 2022

Text Block [Abstract]

Stock-Based Compensation

10.

Stock-Based Compensation

The Company recognized stock-based compensation expense on all employee and non-employee awards as follows:


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
(in thousands)	2022		2021		2022		2021
Research and development		145		535		673		2,115
General and administrative		663		1,836		1,978		7,742
Stock-based compensation expense	$	808	$	2,371	$	2,651	$	9,857

The Company granted an aggregate of 1,275,000 stock options during the three months ended September 30, 2022, with a weighted-average grant date fair value of $1.52 per share, and granted an aggregate of 4,667,500 stock options during the nine months ended September 30, 2022, with a weighted-average grant date fair value of $0.67 per share. The Company granted an aggregate of 2,755,000 stock options during the three months ended September 30, 2021, with a weighted-average grant date fair value of $1.08 per share, and granted an aggregate of 7,150,438 stock options during the nine months ended September 30, 2021, with a weighted-average grant date fair value of $1.91 per share.

For the three and nine months ended September 30, 2022 and 2021, the fair value of stock options was estimated on the date of grant using a Black-Scholes option valuation model with the following assumptions:


	For the Three Months Ended September 30,		For the Nine Months Ended September 30,
	2022	2021	2022	2021
Risk-free interest rate	2.94 – 3.62%	0.89 – 0.96%	1.63 – 3.62%	0.50 – 1.15%
Expected life in years	6.23 - 6.25	6.00 - 6.25	5.27 - 6.25	5.50 - 6.25
Expected volatility	82.43 - 85.89%	72.53 - 72.84%	74.49 - 85.89%	72.53 - 74.80%
Expected dividend yield	—%	—%	—%	—%

Stock option activity under the Company’s stock option plans for the nine months ended September 30, 2022 is 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		10,665,869		$	2.87
Granted		4,667,500			1.08
Exercised		(26,250	)		0.80
Cancelled		(4,683,904	)		3.40
Outstanding, September 30, 2022		10,623,215		$	1.85		8.27	$	3,572
Options exercisable, September 30, 2022		3,211,631		$	2.69		7.01	$	510
Options exercisable, December 31, 2021		4,410,312		$	3.85		7.53	$	—
Options available for future grant, September 30, 2022		15,245,494

At September 30, 2022, total unrecognized compensation costs related to unvested stock options outstanding amounted to $7.1 million. The cost is expected to be recognized over a weighted-average period of 2.01 years.

A summary of the status of unvested restricted stock for the nine months ended September 30, 2022 is as follows:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested, December 31, 2021		1,198,580		$	2.10
Granted		280,000			0.82
Vested		(305,679	)		2.28
Cancelled		(232,901	)		3.15
Unvested, September 30, 2022		940,000		$	1.41

At September 30, 2022, total unrecognized compensation costs related to unvested restricted stock outstanding amounted to $1.2 million. The cost is expected to be recognized over a weighted-average period of 1.83 years.

Warrants

9 Months Ended

Sep. 30, 2022

Warrants Disclosure [Abstract]

Warrant

11.

Warrants

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

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

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

On October 22, 2019, the Company entered into the 2019 R&D Agreement with MD Anderson. In connection with the execution of the 2019 R&D Agreement, the Company issued the MD Anderson Warrant to purchase 3,333,333 shares of common stock. The MD Anderson Warrant has an initial exercise price of $0.001 per share and grant date fair value of $14.5 million. The MD Anderson Warrant expires on December 31, 2026 and vests upon the occurrence of certain clinical milestones. The Company will recognize expense on the MD Anderson Warrant in the same manner as if the Company paid cash for services to be rendered. For the three and nine months ended September 30, 2022 and September 30, 2021, the Company did not recognize any expense related to the MD Anderson Warrant as the clinical milestones had not been achieved.

On August 6, 2021, the Company entered into the Loan and Security Agreement with SVB. Refer to Note 4 - Debt. In connection with the Loan and Security Agreement, the Company issued SVB warrants to purchase 432,844 shares of common stock with an exercise

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

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

Joint Venture

9 Months Ended

Sep. 30, 2022

Equity Method Investments and Joint Ventures [Abstract]

Joint Venture

12.

Joint Venture

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

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

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

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

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

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

In September 2021, TriArm and the Company mutually agreed to dissolve the joint venture.

For the three and nine months ended September 30, 2022 and September 30, 2021, Eden BioCell incurred a net loss. The Company continues to have no commitment to fund its operations.

Subsequent Events

9 Months Ended

Sep. 30, 2022

Subsequent Events [Abstract]

Subsequent Events

13.

Subsequent Events

The Company has evaluated subsequent events from the balance sheet date through the date on which these financial statements were issued. The Company did not have any material subsequent events that impacted its financial statements or disclosures.

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited interim financial statements have been prepared in accordance with the instructions to Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission, or the SEC. Certain information and note disclosures required by generally accepted accounting principles in the United States, or GAAP, have been condensed or omitted pursuant to such rules and regulations. It is management’s opinion that the accompanying unaudited interim financial statements reflect all adjustments (which are normal and recurring) that are necessary for a fair presentation of the financial position of the Company and its results of operations and cash flows for the periods presented. The unaudited interim financial statements should be read in conjunction with the audited financial statements and the notes thereto for the year ended December 31, 2021, included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 filed with the SEC on March 30, 2022, or the Annual Report. The results disclosed in the statements of operations for the three and nine months ended September 30, 2022 are not necessarily indicative of the results to be expected for the full fiscal year 2022.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with 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 revenues 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.

Debt (Tables)

9 Months Ended

Sep. 30, 2022

Debt Disclosure [Abstract]

Schedule of Debt

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


	September 30,			December 31,
($ in thousands)	2022			2021
Loan and Security Agreement	$	23,461		$	25,209
Unamortized discount on Loan and Security Agreement		(793	)		(1,091	)
Total debt	$	22,668		$	24,118

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

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 September 30, 2022 and December 31, 2021 are as follows:


($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of September 30, 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	$	36,807	$	36,807	$	—	$	—


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

Net Loss per Share (Tables)

9 Months Ended

Sep. 30, 2022

Earnings Per Share [Abstract]

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

Such potentially dilutive shares of common stock consisted of the following as of September 30, 2022 and 2021, respectively:


	September 30,
	2022		2021
Common stock options		10,623,215		11,072,894
Inducement stock options		-		97,500
Unvested restricted stock		940,000		1,510,655
Warrants		22,922,342		22,705,571
		34,485,557		35,386,620

Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2022

Text Block [Abstract]

Stock-Based Compensation Expense on All Employee and Non-Employee Awards

The Company recognized stock-based compensation expense on all employee and non-employee awards as follows:


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
(in thousands)	2022		2021		2022		2021
Research and development		145		535		673		2,115
General and administrative		663		1,836		1,978		7,742
Stock-based compensation expense	$	808	$	2,371	$	2,651	$	9,857

Fair Value of Stock Options Assumptions Using Black-Scholes Option Valuation Model


	For the Three Months Ended September 30,		For the Nine Months Ended September 30,
	2022	2021	2022	2021
Risk-free interest rate	2.94 – 3.62%	0.89 – 0.96%	1.63 – 3.62%	0.50 – 1.15%
Expected life in years	6.23 - 6.25	6.00 - 6.25	5.27 - 6.25	5.50 - 6.25
Expected volatility	82.43 - 85.89%	72.53 - 72.84%	74.49 - 85.89%	72.53 - 74.80%
Expected dividend yield	—%	—%	—%	—%

Stock Option Activity under Stock Option Plan

Stock option activity under the Company’s stock option plans for the nine months ended September 30, 2022 is 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		10,665,869		$	2.87
Granted		4,667,500			1.08
Exercised		(26,250	)		0.80
Cancelled		(4,683,904	)		3.40
Outstanding, September 30, 2022		10,623,215		$	1.85		8.27	$	3,572
Options exercisable, September 30, 2022		3,211,631		$	2.69		7.01	$	510
Options exercisable, December 31, 2021		4,410,312		$	3.85		7.53	$	—
Options available for future grant, September 30, 2022		15,245,494

Summary of Unvested Restricted Stock

A summary of the status of unvested restricted stock for the nine months ended September 30, 2022 is as follows:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested, December 31, 2021		1,198,580		$	2.10
Granted		280,000			0.82
Vested		(305,679	)		2.28
Cancelled		(232,901	)		3.15
Unvested, September 30, 2022		940,000		$	1.41

Organization - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Cash and cash equivalents	$ 37,807	$ 76,054
Restricted cash related to the Company's debt agreement	13,900
Accumulated deficit	$ 871,468	$ 842,852
Common stock, shares authorized	420,000,000	350,000,000
Common stock, shares outstanding	216,182,042	216,127,443
Common Stock [Member]
Common stock, shares outstanding	216,182,042
Common stock reserved for future issuance	33,545,557

Financings - Additional Information (Details) - USD ($) $ in Millions		3 Months Ended	9 Months Ended
	Aug. 12, 2022	Sep. 30, 2022	Sep. 30, 2022	Aug. 06, 2021
Share-Based Payment Arrangement, Tranche One [Member] \| Silicon Valley Bank [Member]
Class of Stock [Line Items]
Initial term loan				$ 25.0
Share-Based Payment Arrangement, Tranche Two [Member] \| Silicon Valley Bank [Member]
Class of Stock [Line Items]
Additonal tranche facility				$ 25.0
Equity Distribution Agreement
Class of Stock [Line Items]
Sale of stock during period			0
Stock Issued During Period, Shares, New Issues		0
Aggregate offering price	$ 50.0
Percentage Of Commission On Gross Proceeds From Sale Of Common Stock	3.00%

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total debt	$ 22,668	$ 24,118
Less: current portion of long-term debt	(22,668)	(7,868)
Long-term debt	0	16,250
Silicon Valley Bank Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	23,461	25,209
Unamortized discount on Term Loan Agreement	$ (793)	$ (1,091)

Debt - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended		9 Months Ended
	Dec. 28, 2021	Aug. 06, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Debt Instrument [Line Items]
Line of credit facility, interest rate					4.50%
Interest expense amortized date					Aug. 01, 2023
Interest expense			$ 0.8	$ 0.4	$ 2.3	$ 0.4
Restricted cash related to the Company's debt agreement			13.9		$ 13.9
Term Loan [Member]
Debt Instrument [Line Items]
Interest rate					10.75%
Percentage of original principal due as a final payment		5.75%
Line of credit facility, interest rate					7.75%
Cash proceeds from sale of equity		$ 50.0
Silicon Valley Bank Loan [Member]
Debt Instrument [Line Items]
Warrants issued	649,615
Warrants expiration date	Aug. 06, 2031
Description of payment terms		The Company will also owe SVB 5.75% of the original principal amounts borrowed as a final payment (the "Final Payment"). The Company is permitted to make up to two prepayments, subject to a prepayment premium of the amount being prepaid, ranging from 1.00% to 2.00%, of the SVB Facility, each such prepayment to be at least $5.0 million plus all accrued and unpaid interest on the portion being prepaid.
Debt instrument description of variable rate basis					The SVB Facility bears interest at a floating rate per annum on outstanding loans, payable monthly, at the greater of (a) 7.75% and (b) the current published U.S. prime rate, plus a margin of 4.5%
Prepayment premium		$ 5.0
Number of warrants issued		432,844
Warrant exercise per share	$ 1.16	$ 2.22
Additional number warrants issued		432,842
Debt instrument, initial maturity date					Aug. 01, 2023
Silicon Valley Bank Loan [Member] \| Debt Instrument Redemption Period One \| Maximum
Debt Instrument [Line Items]
Percentage of prepayments premium					2.00%
Silicon Valley Bank Loan [Member] \| Debt Instrument Redemption Period One \| Minimum
Debt Instrument [Line Items]
Percentage of prepayments premium					1.00%
Silicon Valley Bank Loan [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Fully drawn amount					$ 25.0
Restricted cash related to the Company's debt agreement			$ 13.9		$ 13.9
Silicon Valley Bank Loan [Member] \| Term Loan [Member] \| Tenth Scheduled Payment Member
Debt Instrument [Line Items]
Proceeds from collateral account	$ 4.0
Silicon Valley Bank Loan [Member] \| Term Loan [Member] \| Eighth Scheduled Payment
Debt Instrument [Line Items]
Proceeds from collateral account	2.5
Silicon Valley Bank Loan [Member] \| Warrants
Debt Instrument [Line Items]
Issuance costs	$ 1.2

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 36,807	$ 75,222
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 36,807	$ 75,222

Fair Value Measurements (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Fair Value, Inputs, Level 2, and Level 3 Member
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 0

Net Loss Per Share - Potential Dilutive Shares Excluded from Computation of Diluted Net Loss Per Share (Details) - shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	34,485,557	35,386,620
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	22,922,342	22,705,571
Common Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	10,623,215	11,072,894
Inducement Stock Options \| Two Thousand Twelve Stock Option Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	97,500
Unvested Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	940,000	1,510,655

Related Party Transactions - Additional Information (Details) - USD ($) $ in Millions				3 Months Ended		9 Months Ended
	Feb. 19, 2021	Feb. 04, 2021	Dec. 18, 2018	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Vineti Inc [Member] \| Collaborative Arrangement [Member]
Related Party Transaction [Line Items]
Related Party Transaction Expenses From Transactions With Related Party Advisory Fees				$ 0.0	$ 0.1	$ 0.0	$ 0.4
Eden Biocell [Member]
Related Party Transaction [Line Items]
Payments to Fund Long-term Loans to Related Parties			$ 10.0
Additional Loans Committed			$ 25.0
WatermillAndRobertWPostmaMember
Related Party Transaction [Line Items]
Pocket expenses		$ 0.4
Fees and Expenses, Related Party		$ 0.7
Related party transaction, reimbursed amount	$ 0.4

Commitments and Contingencies - Additional Information (Details) - USD ($)				1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	May 28, 2019	Aug. 17, 2015	Jan. 13, 2015	Mar. 31, 2023	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2019	Oct. 22, 2019	Feb. 19, 2019	Oct. 05, 2018	Aug. 24, 2004
Accrued Payments
Research and development expense					$ 7,893,000	$ 14,521,000	$ 19,411,000	$ 41,427,000
Collaboration revenue					2,911,000	398,000	2,911,000	398,000
MD Anderson Warrant [Member]
Accrued Payments
Number of Warrants										3,333,333
Warrant exercise per share										$ 0.001
Warrant Expiry date										Dec. 31, 2026
MD Anderson Agreement and Worldwide License [Member]
Accrued Payments
License agreement commencing date			Jan. 13, 2015
MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Reimbursement of historical costs										$ 20,000,000.0
Quarterly expense incurred					300,000	0	700,000	0
Aggregate potential benchmark payments										36,500,000
Payments due prior to the first marketing approval										$ 3,000,000.0
CRADA Agreement [Member]
Accrued Payments
Quarterly expense incurred					0	0	0	1,300,000
Contribution payable on per annum basis				$ 1,000,000.0
Obligations due under contract											$ 5,000,000.0
CAR Products [Member]
Accrued Payments
Maximum Royalty Amount												$ 100,000,000.0
The University of Texas MD Anderson Cancer Center and The Texas A & M University System
Accrued Payments
Milestone maximum payment													$ 4,500,000
Payment under license agreement						100,000		100,000
One time milestone payment					2,500,000		2,500,000
The University of Texas MD Anderson Cancer Center and The Texas A & M University System \| Royalty [Member]
Accrued Payments
Payment under license agreement					0	0	0	0
License Agreement with the National Cancer Institute [Member]
Accrued Payments
License Expense					100,000	300,000	500,000	600,000
License Agreement with the National Cancer Institute [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
First benchmark payment	$ 100,000
Ziop License Agreement With The National Cancer Institute [Member]
Accrued Payments
Minimum royalties amount payable	300,000
Royalties amount payable thereafter	100,000
Aggregate minimum annual royalties paid	$ 1,500,000
Description Of First Benchmark Payable	The first benchmark payment of $0.1 million was due upon the initiation of the Company's first sponsored Phase 1 clinical trial of a licensed product or licensed process in the field of use licensed under the Patent License. The Company paid the first benchmark payment during the nine months ended September 30, 2022.
Description Of option To terminate Agreement	The NCI may terminate or modify the Patent License in the event of a material breach, including if the Company does not meet certain milestones by certain dates, or upon certain insolvency events that remain uncured following the date that is 90 days following written notice of such breach or insolvency event.
Agreement termination, notice period	60 days
Ziop License Agreement With The National Cancer Institute [Member] \| Performance Based Payments Member [Member]
Accrued Payments
Aggregate Benchmark Payments Payable	$ 4,300,000
Ziop License Agreement With The National Cancer Institute [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
Potential Benchmark Payments Payable	12,000,000.0
Ziop License Agreement With The National Cancer Institute [Member] \| Post Marketing Approval [Member] \| Performance Based Payments Member [Member]
Accrued Payments
Aggregate Benchmark Payments Payable	3,000,000.0
Ziop License Agreement With The National Cancer Institute [Member] \| licensed products [Member] \| One Time Benchmark Payments [Member]
Accrued Payments
Maximum Sales Revenue On Which Benchmark Payments Payable	1,000,000,000.0
Minimum sales revenue on which benchmark payments payable	$ 250,000,000.0
Collaboration Agreement With Solasia Pharma KK [Member]
Accrued Payments
Collaboration revenue						400,000		400,000
Collaboration Agreement With Solasia Pharma KK [Member] \| Royalty [Member]
Accrued Payments
Collaboration revenue					$ 0	$ 0	$ 0	$ 0
Intrexon Corporation
Accrued Payments
Annual License Fees												100,000
Expected additional milestones payable												52,500,000
Payment for historical costs of the licensed programs									$ 1,000,000.0
Intrexon Corporation \| T-cell receptor
Accrued Payments
Maximum royalty amount												$ 100,000,000.0
Portion of income payable to related party												20.00%
Minimum \| MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Research and development expense		$ 15,000,000.0
Maximum \| MD Anderson License and the Research and Development Agreement [Member]
Accrued Payments
Research and development expense		$ 20,000,000.0

Leases - Additional Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Leases - Additional Information (Details) $ in Thousands	Sep. 30, 2022 USD ($) ft²	Sep. 30, 2022 USD ($) ft²	Dec. 31, 2021 USD ($)
Right of use asset	$ 2,247	$ 2,247	$ 4,420
Gain (Loss) On Modification Of Lease		$ 100
SubleaseArea \| ft²	4,772	4,772
Lease term, description		The term of the sub-sublease is from July 1, 2022 to June 30, 2025 and provides the sub-subtenant with an option to extend through to July 31, 2026
Other Income Expense [Member]
Lease income	$ 44	$ 44
Houston, TX
Operating Lease Area \| ft²	3,228	3,228
Right of use asset	$ 400	$ 400
Previously Reported \| Houston, TX
Operating Lease Area \| ft²	18,111	18,111

Stock-Based Compensation Expense Included in Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 808	$ 2,371	$ 2,651	$ 9,857
Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	145	535	673	2,115
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 663	$ 1,836	$ 1,978	$ 7,742

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted	1,275,000	2,755,000	4,667,500	7,150,438
Weighted-average grant date fair value	$ 1.52	$ 1.08	$ 0.67	$ 1.91
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding	$ 7.1		$ 7.1
Expected recognition period			2 years 3 days
Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding	$ 1.2		$ 1.2
Expected recognition period			1 year 9 months 29 days

Stock-Based Compensation - Fair Value of Stock Options Assumptions Using Black-Scholes Option Valuation Model (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Risk-free interest rate, Minimum	2.94%	0.89%	1.63%	0.50%
Risk-free interest rate, Maximum	3.62%	0.96%	3.62%	1.15%
Expected volatility, Minimum	82.43%	72.53%	74.49%	72.53%
Expected volatility, Maximum	85.89%	72.84%	85.89%	74.80%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Maximum [Member]
Expected life in years	6 years 3 months	6 years 3 months	6 years 3 months	6 years 3 months
Minimum [Member]
Expected life in years	6 years 2 months 23 days	6 years	5 years 3 months 7 days	5 years 6 months

Stock-Based Compensation - Stock Option Activity Under Stock Option Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Number of Shares
Beginning Balance			10,665,869
Granted	1,275,000	2,755,000	4,667,500	7,150,438
Exercised			(26,250)
Cancelled			(4,683,904)
Ending Balance	10,623,215		10,623,215		10,665,869
Options exercisable, at end of period	3,211,631		3,211,631		4,410,312
Options available for future grant	15,245,494		15,245,494
Weighted Average Exercise Price
Beginning Balance			$ 2.87
Granted			1.08
Exercised			0.80
Cancelled			3.40
Ending Balance	$ 1.85		1.85		$ 2.87
Options exercisable, at end of period	$ 2.69		$ 2.69		$ 3.85
Weighted Average Contractual Term (Years)
Outstanding, at end of period			8 years 3 months 7 days
Options exercisable, at end of period			7 years 3 days		7 years 6 months 10 days
Aggregate Intrinsic Value
Outstanding, at end of period	$ 3,572		$ 3,572
Options exercisable, at end of period	$ 510		$ 510		$ 0

Stock-Based Compensation - Summary of Non-Vested Restricted Stock (Details) - Non Vested Restricted Stock [Member]	9 Months Ended
	Sep. 30, 2022 $ / shares shares
Number of Shares
Beginning Balance \| shares	1,198,580
Granted \| shares	280,000
Vested \| shares	(305,679)
Cancelled \| shares	(232,901)
Ending Balance \| shares	940,000
Weighted Average Grant Date Fair Value
Beginning Balance \| $ / shares	$ 2.10
Granted \| $ / shares	0.82
Vested \| $ / shares	2.28
Cancelled \| $ / shares	3.15
Ending Balance \| $ / shares	$ 1.41

Warrants - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands						3 Months Ended		9 Months Ended
	Dec. 28, 2021	Aug. 06, 2021	Oct. 22, 2019	Sep. 12, 2019	Nov. 11, 2018	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Fair Value Assumptions Expected volatility Rate Maximum						85.89%	72.84%	85.89%	74.80%
Fair Value Assumptions Risk Free Interest Rate Maximum						3.62%	0.96%	3.62%	1.15%
Proceeds from private placement				$ 52,500
Silicon Valley Bank Loan [Member]
Warrant exercise per share	$ 1.16	$ 2.22
Number of warrants issued		432,844
MD Anderson Warrant [Member]
Number of securities into which the class of warrant converted			3,333,333
Warrant exercise per share			$ 0.001
Fair value of warrants			$ 14,500
Warrant Expiry date			Dec. 31, 2026
SVB Warrants [Member]
Common stock		432,844
Exercise price		$2.22
Warrants fully vested upon issuance		10 years
Black-Scholes Model [Member] \| Silicon Valley Bank Loan [Member]
Fair Value Assumptions Expected Term1	10 years
Exercise price	$1.16
Expected volatility	81.00%
Risk-free interest rate	1.49%
Number of warrants issued	649,615
Dividends	$ 0
Change in fair value	$ 200
Black-Scholes Model [Member] \| SVB Warrants [Member]
Fair value of warrants		$ 800
Fair Value Assumptions Expected Term1		10 years
Expected volatility		79.00%
Risk-free interest rate		1.31%
Dividends		$ 0
Securities Purchase Agreement [Member]
Aggregate offering price					$ 47,100
Private Placement [Member]
Number of securities into which the class of warrant converted				17,803,031	18,939,394
Warrant exercise per share				$ 3.01	$ 3.01
Fair value 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				17,803,031
Warrant exercise per share				$ 7.00
Non-cash inducement warrant expense				$ 60,800

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%