0001485003-22-000156 | 10-Q | XBRL Viewer

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Cover - shares	9 Months Ended
Cover - shares	Sep. 30, 2022	Oct. 31, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2022
Document Transition Report	false
Entity File Number	001-36296
Entity Registrant Name	Sesen Bio, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-2025616
Entity Address, Address Line One	245 First Street
Entity Address, Address Line Two	Suite 1800
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02142
City Area Code	617
Local Phone Number	444-8550
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	SESN
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		202,757,012
Entity Central Index Key	0001485003
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 71,107	$ 162,636
Short term marketable securities	106,427	0
Accounts receivables	0	21,011
Other receivables	14,297	3,482
Prepaid expenses and other current assets	527	18,476
Total current assets	192,358	205,605
Non-current assets:
Restricted cash	30	20
Marketable securities	7,336	0
Property and equipment, net	0	43
Intangible assets	0	14,700
Goodwill	0	13,064
Long term prepaid expenses	0	7,192
Other assets	0	123
Total non-current assets	7,366	35,142
Total Assets	199,724	240,747
Current liabilities:
Accounts payable	514	2,853
Accrued expenses	33,800	8,255
Other current liabilities	381	460
Total current liabilities	34,695	11,568
Non-current liabilities:
Contingent consideration	0	52,000
Deferred tax liability	0	3,969
Deferred revenue	0	1,500
Total non-current liabilities	0	57,469
Total Liabilities	34,695	69,037
Stockholders’ Equity:
Preferred stock, $0.001 par value per share; 5,000,000 shares authorized at September 30, 2022 and December 31, 2021; no shares issued and outstanding at September 30, 2022 and December 31, 2021	$ 0	$ 0
Common stock, shares outstanding (in shares)	202,757,012	199,463,645
Common stock, $0.001 par value per share; 400,000,000 shares authorized at September 30, 2022 and December 31, 2021; 202,757,012 and 199,463,645 shares issued and outstanding at September 30, 2022 and December 31, 2021, respectively	$ 202	$ 199
Additional paid-in capital	493,629	487,768
Other comprehensive loss	(235)	0
Accumulated deficit	(328,567)	(316,257)
Total Stockholders’ Equity	165,029	171,710
Total Liabilities and Stockholders’ Equity	$ 199,724	$ 240,747
Common stock, shares issued (in shares)	202,757,012	199,463,645

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	May 03, 2021	May 02, 2021
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0	0
Preferred stock, shares outstanding (in shares)	0	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	400,000,000	400,000,000		400,000,000	200,000,000
Common stock, shares issued (in shares)	202,757,012	199,463,645
Common stock, shares outstanding (in shares)	202,757,012	199,463,645

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (OPERATIONS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Total revenue	$ 40,000	$ 0	$ 40,000	$ 6,544
Operating expenses:
Research and development	2,931	4,967	37,636	18,273
General and administrative	8,141	8,699	32,705	20,797
Restructuring charge	10,947	5,522	10,947	5,522
Intangibles impairment charge	0	31,700	27,764	31,700
Change in fair value of contingent consideration	(1,800)	(114,000)	(52,000)	(52,240)
Total operating expenses	20,219	(63,112)	57,052	24,052
Income (Loss) from Operations	19,781	63,112	(17,052)	(17,508)
Other income (expense), net	676	1	867	(45)
Income (Loss) Before Taxes	20,457	63,113	(16,185)	(17,553)
Benefit from income taxes	0	8,561	3,875	8,273
Net Income (Loss) After Taxes	20,457	71,674	(12,310)	(9,280)
Net income (loss) attributable to common stockholders - basic	20,442	71,622	(12,310)	(9,280)
Net income (loss) attributable to common stockholders - diluted	$ 20,442	$ 71,623	$ (12,310)	$ (9,280)
Net loss per common share - basic (in dollars per share)	$ 0.10	$ 0.36	$ (0.06)	$ (0.05)
Weighted-average common shares outstanding - basic (in shares)	200,464	196,778	199,801	176,547
Net loss per common share - diluted (in dollars per share)	$ 0.10	$ 0.36	$ (0.06)	$ (0.05)
Weighted-average common shares outstanding - diluted (in shares)	200,947	201,017	199,801	176,547
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]	License [Member]	License [Member]	License [Member]	License [Member]

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net Income (Loss) Attributable to Parent	$ 20,457	$ 71,674	$ (12,310)	$ (9,280)
Unrealized (gain) loss on marketable securities	(46)	0	235	0
Total comprehensive income (loss)	$ 20,503	$ 71,674	$ (12,545)	$ (9,280)

- Definition

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

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+ Details

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	ATM Facility	Common Stock	Common Stock ATM Facility	Additional Paid-in Capital	Additional Paid-in Capital ATM Facility	Accumulated Other Comprehensive Loss Investments	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2020			140,449,647
Beginning balance at Dec. 31, 2020	$ (9,227)		$ 140		$ 306,554			$ (315,921)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(55,512)							(55,512)
Share-based compensation	958				958
Exercise of stock options (in shares)			30,610
Exercises of stock options	39				39
Exercise of common stock warrants (in shares)			852,840
Exercises of common stock warrants	469		$ 1		468
Issuance of common stock and common stock warrants (in shares)				30,645,702
Issuance of common stock and common stock warrants		$ 72,543		$ 31		$ 72,512
Ending balance (in shares) at Mar. 31, 2021			171,978,799
Ending balance at Mar. 31, 2021	9,270		$ 172		380,531			(371,433)
Beginning balance (in shares) at Dec. 31, 2020			140,449,647
Beginning balance at Dec. 31, 2020	(9,227)		$ 140		306,554			(315,921)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(9,280)
Unrealized gain of investments	0
Ending balance (in shares) at Sep. 30, 2021			199,463,645
Ending balance at Sep. 30, 2021	161,008		$ 199		486,010			(325,201)
Beginning balance (in shares) at Mar. 31, 2021			171,978,799
Beginning balance at Mar. 31, 2021	9,270		$ 172		380,531			(371,433)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(25,442)							(25,442)
Share-based compensation	1,260				1,260
Issuance of common stock and common stock warrants (in shares)				16,482,152
Issuance of common stock and common stock warrants		64,261		$ 16		64,245
Ending balance (in shares) at Jun. 30, 2021			188,460,951
Ending balance at Jun. 30, 2021	49,349		$ 188		446,036			(396,875)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	71,674							71,674
Share-based compensation	1,168				1,168
Exercise of stock options (in shares)			3,000
Exercises of stock options	3				3
Exercise of common stock warrants (in shares)			1,195,219
Exercises of common stock warrants	657		$ 1		656
Issuance of common stock and common stock warrants (in shares)				9,804,475
Issuance of common stock and common stock warrants		$ 38,157		$ 10		$ 38,147
Unrealized gain of investments	0
Ending balance (in shares) at Sep. 30, 2021			199,463,645
Ending balance at Sep. 30, 2021	161,008		$ 199		486,010			(325,201)
Beginning balance (in shares) at Dec. 31, 2021			199,463,645
Beginning balance at Dec. 31, 2021	171,710		$ 199		487,768		$ 0	(316,257)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(807)							(807)
Share-based compensation	1,894				1,894
Ending balance (in shares) at Mar. 31, 2022			199,463,645
Ending balance at Mar. 31, 2022	172,797		$ 199		489,662		0	(317,064)
Beginning balance (in shares) at Dec. 31, 2021			199,463,645
Beginning balance at Dec. 31, 2021	171,710		$ 199		487,768		0	(316,257)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ (12,310)
Exercise of stock options (in shares)	0
Exercise of common stock warrants (in shares)	0
Unrealized gain of investments	$ (235)
Ending balance (in shares) at Sep. 30, 2022			202,757,012
Ending balance at Sep. 30, 2022	165,029		$ 202		493,629		(235)	(328,567)
Beginning balance (in shares) at Mar. 31, 2022			199,463,645
Beginning balance at Mar. 31, 2022	172,797		$ 199		489,662		0	(317,064)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(31,960)							(31,960)
Share-based compensation	1,802				1,802
Unrealized gain of investments	(281)						(281)
Ending balance (in shares) at Jun. 30, 2022			199,463,645
Ending balance at Jun. 30, 2022	142,358		$ 199		491,464		(281)	(349,024)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	20,457							20,457
Share-based compensation (in shares)			3,293,367
Share-based compensation	2,168		$ 3		2,165
Unrealized gain of investments	46						46
Ending balance (in shares) at Sep. 30, 2022			202,757,012
Ending balance at Sep. 30, 2022	$ 165,029		$ 202		$ 493,629		$ (235)	$ (328,567)

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021
Statement of Stockholders' Equity [Abstract]
Issuance costs	$ 1.2	$ 2.0	$ 2.2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash Flows from Operating Activities:
Net Income (Loss) Attributable to Parent	$ (12,310)	$ (9,280)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	13	74
Share-based compensation	5,864	3,386
Change in fair value of contingent consideration	(52,000)	(52,240)
Intangibles impairment charge	27,764	31,700
Changes in operating assets and liabilities:
Accounts receivable (net)	21,012	(1,107)
Other receivables	(10,816)	0
Prepaid expenses and other current assets	17,949	(23,665)
Long term prepaid expenses	7,192	0
Unrealized loss on marketable securities	(235)	0
Other assets	123	0
Accounts payable	(2,339)	807
Accrued expenses and other liabilities	21,497	(4,453)
Deferred revenue	(1,500)	(1,500)
Net cash provided by (used in) operating activities	22,214	(56,278)
Cash Flows from Investing Activities:
Purchase of marketable securities	(113,763)	0
Disposal (purchase) of equipment	30
Disposal (purchase) of equipment		(4)
Net cash used in investing activities	(113,733)	(4)
Cash Flows from Financing Activities:
Proceeds from issuance of common stock under ATM Offering, net of issuance costs	0	174,961
Proceeds from exercises of stock options	0	42
Proceeds from exercises of common stock warrants	0	1,126
Net cash provided by financing activities	0	176,129
Net (decrease) increase in cash, cash equivalents and restricted cash	(91,519)	119,847
Cash, cash equivalents and restricted cash - beginning of period	162,656	55,409
Cash, cash equivalents and restricted cash - end of period	71,137	175,256
Supplemental cash flow disclosure:
Cash paid for amounts included in the measurement of lease liabilities	$ 127	$ 131

DESCRIPTION OF BUSINESS	9 Months Ended
DESCRIPTION OF BUSINESS	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
DESCRIPTION OF BUSINESS	DESCRIPTION OF BUSINESS Sesen Bio, Inc. ("Sesen Bio" or the “Company”), a Delaware corporation formed in February 2008, is a late-stage clinical company focused on advancing targeted fusion protein therapeutics for the treatment of patients with cancer. The Company’s most advanced product candidate, VicineumTM, also known as VB4-845, is a locally-administered targeted fusion protein composed of an anti-epithelial cell adhesion molecule ("EpCAM") antibody fragment tethered to a truncated form of Pseudomonas exotoxin A for the treatment of non-muscle invasive bladder cancer (“NMIBC”). On July 15, 2022, the Company made the strategic decision to voluntarily pause further development of Vicineum in the United States. The decision was based on a thorough reassessment of Vicineum following recent discussions with the United States Food and Drug Administration ("FDA"), which had implications on the size, timeline and costs of an additional Phase 3 clinical trial, which the FDA previously confirmed would be required for a potential resubmission of a biologics license application ("BLA") for Vicineum for the treatment of NMIBC. The Company continues to believe that Vicineum has benefits for patients and healthcare providers that can be maximized through a company with a larger infrastructure, and as such, intends to seek a partner that can execute further development to realize the full potential of Vicineum. As a result of this decision, the Company has turned its primary focus to the careful assessment of potential strategic alternatives with the goal of maximizing shareholder value. Anticipated Merger with CARISMA Therapeutics Inc. Following an extensive process of evaluating strategic alternatives, including identifying and reviewing potential candidates for a strategic transaction, on September 20, 2022, Sesen Bio, Seahawk Merger Sub, Inc., a Delaware corporation and wholly-owned subsidiary of Sesen Bio (“Merger Sub”), and CARISMA Therapeutics Inc., a Delaware corporation (“Carisma”), entered into an Agreement and Plan of Merger and Reorganization (the “Merger Agreement”), pursuant to which, among other things, and subject to the satisfaction or waiver of certain conditions set forth in the Merger Agreement, Merger Sub will merge with and into Carisma, with Carisma continuing as a wholly-owned subsidiary of Sesen Bio and the surviving corporation of the merger (the “Merger”). Sesen Bio's board of directors unanimously approved the Merger Agreement and resolved to recommend that Sesen Bio’s stockholders approve the proposals described in the Merger Agreement. If the Merger is completed, the business of Carisma will continue as the business of the combined company. Sesen Bio’s future operations are highly dependent on the success of the Merger and there can be no assurances that the Merger will be successfully consummated. In the event that Sesen Bio does not complete the Merger with Carisma, Sesen Bio may continue to review and evaluate a strategic alternatives, including, without limitation, another strategic transaction and/or pursue a liquidation and dissolution of Sesen Bio. Viventia Acquisition In September 2016, the Company entered into a Share Purchase Agreement with Viventia Bio, Inc., a corporation incorporated under the laws of the Province of Ontario, Canada ("Viventia"), the shareholders of Viventia named therein (the “Selling Shareholders”) and, solely in its capacity as seller representative, Clairmark Investments Ltd., a corporation incorporated under the laws of the Province of Ontario, Canada (the “Share Purchase Agreement”), pursuant to which the Company agreed to and simultaneously completed the acquisition of all of the outstanding capital stock of Viventia from the Selling Shareholders (the “Viventia Acquisition”). In connection with the closing of the Viventia Acquisition, the Company issued 4.0 million shares of its common stock to the Selling Shareholders, which at that time represented approximately 19.9% of the voting power of the Company as of immediately prior to the issuance of such shares. In addition, under the Share Purchase Agreement, the Company is obligated to pay to the Selling Shareholders certain post-closing contingent cash payments upon the achievement of specified milestones and based upon net sales, in each case subject to the terms and conditions set forth in the Share Purchase Agreement, including: (i) a one-time milestone payment of $12.5 million payable upon the first sale of Vicineum (the “Purchased Product”), in the United States; (ii) a one-time milestone payment of $7.0 million payable upon the first sale of the Purchased Product in any one of certain specified European countries; (iii) a one-time milestone payment of $3.0 million payable upon the first sale of the Purchased Product in Japan; and (iv) quarterly earn-out payments equal to 2% of net sales of the Purchased Product during specified earn-out periods. Such earn-out payments are payable with respect to net sales in a country beginning on the date of the first sale in such country and ending on the earlier of (i) December 31, 2033, and (ii) fifteen years after the date of such sale, subject to early termination in certain circumstances if a biosimilar product is on the market in the applicable country. Under the Share Purchase Agreement, the Company, its affiliates, licensees and subcontractors are required to use commercially reasonable efforts, for the first seven years following the closing of the Viventia Acquisition, to achieve marketing authorizations throughout the world and, during the applicable earn-out period, to commercialize the Purchased Product in the United States, France, Germany, Italy, Spain, United Kingdom, Japan, China and Canada. Certain of these payments are payable to individuals or affiliates of individuals that became employees or members of the Company's board of directors. However, as of September 30, 2022, none of these individuals are active employees of the Company or members of the Company's board of directors.

BASIS OF PRESENTATION	9 Months Ended
BASIS OF PRESENTATION	Sep. 30, 2022
Accounting Policies [Abstract]
BASIS OF PRESENTATION	BASIS OF PRESENTATION The accompanying financial statements have been prepared in accordance with United States generally accepted accounting principles ("GAAP"). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates ("ASUs"), promulgated by the Financial Accounting Standards Board ("FASB"). Interim Financial Statements The accompanying unaudited interim condensed consolidated financial statements have been prepared from the books and records of the Company in accordance with GAAP for interim financial information and Rule 10-01 of Regulation S-X promulgated by the United States Securities and Exchange Commission (“SEC”), which permit reduced disclosures for interim periods. All adjustments, consisting only of normal recurring adjustments, which are, in the opinion of management, necessary for a fair presentation of the accompanying condensed consolidated balance sheets and statements of operations and comprehensive (loss) income, stockholders’ equity (deficit) and cash flows have been made. Although these interim financial statements do not include all of the information and footnotes required for complete annual financial statements, management believes the disclosures are adequate to make the information presented not misleading. These unaudited interim results of operations and cash flows for the nine months ended September 30, 2022 are not necessarily indicative of the results that may be expected for the full year. These unaudited interim condensed consolidated financial statements and footnotes should be read in conjunction with the Company’s audited annual consolidated financial statements and footnotes included in its Annual Report on Form 10-K, as filed with the SEC on February 28, 2022, wherein a more complete discussion of significant accounting policies and certain other information can be found. Use of Estimates The preparation of financial statements in accordance with GAAP and the rules and regulations of the SEC requires the use of estimates and assumptions, based on judgments considered reasonable, which affect the reported amounts of assets and liabilities and 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. The Company bases its estimates and assumptions on historical experience, known trends and events and various other factors that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Although management believes its estimates and assumptions are reasonable when made, they are based upon information available at the time they are made. Management evaluates the estimates and assumptions on an ongoing basis and, if necessary, makes adjustments. Due to the risks and uncertainties involved in the Company’s business and evolving market conditions, and given the subjective element of the estimates and assumptions made, actual results may differ from estimated results. The most significant estimates and judgments impact the fair value of intangible assets; goodwill and contingent consideration; income taxes (including the valuation allowance for deferred tax assets); and research and development expenses. Principles of Consolidation The Company’s condensed consolidated financial statements include the accounts of the Company, its wholly owned subsidiaries Viventia and Seahawk Merger Sub, Inc. and its indirect subsidiary, Viventia Bio USA Inc. All intercompany transactions and balances have been eliminated in consolidation. Foreign Currency Translation The functional currency of the Company and each of its subsidiaries is the US dollar.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Sep. 30, 2022
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIESThe Company's complete summary of significant accounting policies can be found in "Item 15. Exhibits and Financial Statement Schedules - Note 3. Summary of Significant Accounting Policies" in the audited annual consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2021.

RECENT ACCOUNTING PRONOUNCEMENTS	9 Months Ended
RECENT ACCOUNTING PRONOUNCEMENTS	Sep. 30, 2022
Accounting Standards Update and Change in Accounting Principle [Abstract]
RECENT ACCOUNTING PRONOUNCEMENTS	RECENT ACCOUNTING PRONOUNCEMENTS Adopted in 2022 In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity ("ASU 2020-06"). ASU 2020-06 simplifies the complexity associated with applying US GAAP for certain financial instruments with characteristics of both liability and equity. More specifically, the amendments focus on the guidance for convertible instruments and derivative scope exception for contracts in an entity’s own equity. The ASU also amends the diluted earnings per share ("EPS") guidance, including the requirement to use the if-converted method for all convertible instruments. ASU 2020-06 is effective for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021, and should be applied on a full or modified retrospective basis. The Company adopted this guidance on a modified retrospective basis effective January 1, 2022 and it did not have an impact on the Company's financial position, results of operations including per-share amounts, or cash flows. In May 2021, the FASB issued ASU No. 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options ("ASU 2021-04"). ASU 2021-04 clarifies and reduces diversity in an issuer’s accounting for modifications or exchanges of freestanding equity-classified written call options (for example, warrants) that remain equity classified after modification or exchange. ASU 2021-04 is effective for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021, and should be applied on a prospective basis. The Company adopted this guidance effective January 1, 2022 and it did not have an impact on the Company's financial position, results of operations including per-share amounts, or cash flows. Other recent accounting pronouncements issued, but not yet effective, are not expected to be applicable to the Company or have a material effect on the consolidated financial statements upon future adoption.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

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+ Details

FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS

The carrying values of cash and cash equivalents, restricted cash, prepaid expenses and other current assets, and accounts payable on the Company’s condensed consolidated balance sheets approximated their fair values as of September 30, 2022 and December 31, 2021 due to their short-term nature.

Certain of the Company’s financial instruments are measured at fair value using a three-level hierarchy that prioritizes the inputs used to measure fair value. This fair value hierarchy prioritizes the use of observable inputs and minimizes the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows:

Level 1: Inputs are quoted prices for identical instruments in active markets.

Level 2: Inputs are quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; or model-derived valuations whose inputs are observable or whose significant value drivers are observable.

Level 3: Inputs are unobservable and reflect the Company’s own assumptions, based on the best information available, including the Company’s own data.

The following tables set forth the carrying amounts and fair values of the Company's financial instruments measured at fair value on a recurring basis as of September 30, 2022 and December 31, 2021 (in thousands):


	September 30, 2022
					Fair Value Measurement Based on
	Carrying Amount		Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Marketable securities:
Money market funds (cash equivalents)	$	11,450	$	11,450	$	11,450	$	—	$	—
Marketable securities	$	113,763	$	113,763	$	—	$	113,763	$	—
Liabilities:

Contingent consideration	$	—	$	—	$	—	$	—	$	—


	December 31, 2021
					Fair Value Measurement Based on
	Carrying Amount		Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Money market funds (cash equivalents)	$	16,382	$	16,382	$	16,382	$	—	$	—
Liabilities:

Contingent consideration	$	52,000	$	52,000	$	—	$	—	$	52,000

The Company evaluates transfers between fair value levels at the end of each reporting period. There were no asset or liability transfers between fair value levels during the nine months ended September 30, 2022 and the year ended December 31, 2021.

Contingent Consideration

On September 20, 2016, the Company acquired Viventia through the issuance of shares of common stock plus contingent consideration, pursuant to the terms of a Share Purchase Agreement. The Company recorded the acquired assets and liabilities based on their estimated fair values as of the acquisition date and finalized its purchase accounting for the Viventia Acquisition during the third quarter of 2017. The contingent consideration relates to amounts potentially payable to the former shareholders of Viventia under the Share Purchase Agreement. Contingent consideration is measured at its estimated fair value at each reporting period, with fluctuations in value resulting in a non-cash charge to earnings (or loss) during the period. The estimated fair value measurement is based on significant inputs, including internally developed financial forecasts, probabilities of success, and the timing of certain milestone events and achievements, which are not observable in the market, representing a Level 3 measurement within the fair value hierarchy. The valuation of contingent consideration requires the use of significant assumptions and judgments, which management believes are consistent with those that would be made by a market participant. Management reviews its assumptions and judgments on an ongoing basis as additional market and other data is obtained, and any future changes in the assumptions and judgments utilized by management may cause the estimated fair value of contingent consideration to fluctuate materially, resulting in earnings volatility.

On July 15, 2022, the Company made the strategic decision to voluntarily pause further development of Vicineum in the United States. The decision was based on a thorough reassessment of Vicineum following recent discussions with the FDA, which had implications on the size, timeline and costs of an additional Phase 3 clinical trial for the treatment of NMIBC. The Company continues to believe that Vicineum has benefits for patients and healthcare providers that can be maximized through a company with a larger infrastructure, and as such intends to seek a partner for the further development of Vicineum. Additionally, during the second quarter of 2022, the Company observed an evolution of the current market treatment paradigm in NMIBC, with substantial uptake of intravesical chemotherapy (monotherapy and combination therapy) during the bacillus Calmette-Guérin (“BCG”) shortage. Accordingly, during the second quarter of 2022, the Company concluded that it no longer expected to pay related milestone and earnout payments to the former shareholders of Viventia, with the exception of the potential 2% earnout payment related to the Greater China region since those territory rights had been out-licensed pursuant to the exclusive license agreement with Qilu Pharmaceutical Co., Ltd. ("Qilu") (the "Qilu License Agreement") (as further described in Note 17. “License Agreements” below). As of June 30, 2022, Qilu held the exclusive license to develop Vicineum in the Greater China region, and accordingly, the $1.8 million estimated earnout payment in the Greater China region remained as long-term contingent consideration as of June 30, 2022.

The Company and Qilu are in the process of negotiating a termination of the Qilu License Agreement. Upon the termination of the Qilu License Agreement, the Company will regain the rights to develop, manufacture and commercialize Vicineum in Greater China. However, the Company does not plan to develop or commercialize Vicineum in that region or any other, as it is pursuing the Merger with Carisma. The Company is also seeking to sell or out-license Vicineum and all the related obligations related to Vicineum. The Company expects that any partner who acquires or licenses Vicineum from the Company will be obligated to make any payments, including those related to sales in the Greater China region (if any), that become payable to the former shareholders of Viventia under the Share Purchase Agreement. If a sale or license of Vicineum has not occurred at the time the Merger is completed, Carisma has indicated it may continue to seek a sale or license of Vicineum and has no plans to develop Vicineum. Accordingly, as of September 30, 2022, the Company concluded that it no longer expects to owe any

future earnout payments related to the Greater China region and reduced its remaining $1.8 million of contingent consideration liabilities to zero as of September 30, 2022.

The contingent consideration balance as of December 31, 2021 was $52.0 million which was based upon projected world-wide net sales. The estimated fair value of the Company’s contingent consideration was determined using probabilities of successful achievement of regulatory milestones and commercial sales, the period in which these milestones and sales are expected to be achieved through 2033, the level of commercial sales of Vicineum forecasted for the US, Europe, Japan, China and other potential markets and discount rates ranging from 8.0% to 9.3% as of December 31, 2021.

The following table sets forth a summary of the change in the fair value of the Company's contingent consideration liability, measured on a recurring basis at each reporting period (in thousands).


Balance at December 31, 2021	$	52,000

Change in fair value of contingent consideration	(52,000)
Balance at September 30, 2022	$	—

The fair value of the Company’s contingent consideration was determined based on the present value of projected future cash flows associated with sales-based milestones and earnouts on net sales and is heavily dependent on discount rates to estimate the fair value at each reporting period. Earnouts were determined using an earnout rate of 2% on all commercial net sales of Vicineum through December 2033. The discount rate applied to the 2% earnout was derived from the Company’s weighted-average cost of capital, which was 9.3% as of December 31, 2021. As of December 31, 2021, the balance also reflected potential milestone payments which constitute debt-like obligations, and therefore a high-yield debt index rate was applied to the milestones in order to determine the estimated fair value. This index rate was 8.0% as of December 31, 2021. The decrease in the fair value of contingent consideration of $52.0 million for the nine months ended September 30, 2022 was driven by the Company's decision to voluntarily pause further development of Vicineum in the United States and seek a partner to acquire or license the asset and assume all associated liabilities.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

RECEIVABLES	9 Months Ended
RECEIVABLES	Sep. 30, 2022
Receivables [Abstract]
RECEIVABLES	RECEIVABLES The accounts receivable balance as of December 31, 2021 was $21.0 million, comprised primarily of a $20 million milestone achieved in December 2021 due to F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc. (collectively, “Roche”) initiating a Phase II clinical trial in the fourth quarter of 2021. In January 2022 the payment of $20 million was received. Additionally, in June 2021, the Qilu License Agreement was recognized by Shandong Province, Bureau of Science and Technology as a "Technology Transfer". As such, the Company recorded $0.9 million of revenue and accounts receivable for the additional purchase price resulting from Qilu's obligation to pay the Company an amount equal to its recovery of value-added tax ("VAT"). The accounts receivable balance as of September 30, 2022 was zero. The other receivables balance as of September 30, 2022 was $14.3 million compared to $3.5 million as of December 31, 2021. The increase of $10.8 million was primarily driven by expected insurance recovery of $13.4 million related to the preliminary settlements of the Securities Litigation and Derivative Litigation (as defined in Note 10. “Commitments and Contingencies” below). This amount was partially offset by the receipt of $2.4 million for German VAT recovery in the first half of 2022, related to drug substance sent to Baxter in 2020 and 2019 and other individually immaterial changes of $0.2 million.

PREPAID EXPENSES	9 Months Ended
PREPAID EXPENSES	Sep. 30, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
PREPAID EXPENSES	PREPAID EXPENSES The prepaid expenses balance as of September 30, 2022 was $0.5 million compared to $25.7 million as of December 31, 2021. In light of the Company's decision to voluntarily pause further development of Vicineum in the United States, the Company evaluated prepaid balances and determined that the prepayments for the manufacturing of Vicineum, including consumables, had no future economic benefit or value. Pursuant to ASC Topic 730, Certain Nonrefundable Advance Payment, the Company expensed $25.2 million of prepayments during the second quarter of 2022.

INTANGIBLE ASSETS AND GOODWIL

9 Months Ended

Sep. 30, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

INTANGIBLE ASSETS AND GOODWIL

INTANGIBLE ASSETS AND GOODWILL

Intangibles

Intangible assets on the Company's condensed consolidated balance sheets are the result of the Viventia Acquisition in September 2016. The following table sets forth the composition of intangible assets as of September 30, 2022 and December 31, 2021 (in thousands):


	September 30, 2022		December 31, 2021
IPR&D intangible assets:

Vicineum European Union rights	$	—	$	14,700
Total Intangibles	$	—	$	14,700

The fair value of the acquired intangible assets for the European Union ("EU") rights of Vicineum is determined using a risk-adjusted discounted cash flow approach, which includes probability adjustments for projected revenues and operating expenses based on the success rates assigned to each stage of development for each geographical region; as well as discount rates applied to the projected cash flows.

During the second quarter of 2022, the Company observed an evolution of the current market treatment paradigm in NMIBC, with substantial uptake of intravesical chemotherapy (monotherapy and combination therapy) during the ongoing BCG shortage. On July 15, 2022, the Company made the strategic decision to voluntarily pause further development of Vicineum in the United States. The decision was based on a thorough reassessment of Vicineum following recent discussions with the FDA, which had implications on the size, timeline and costs of an additional Phase 3 clinical trial for the treatment of NMIBC. Management updated the discounted cash flow model using the market participant approach and considered preliminary terms of a potential partnering deal to conclude the fair value of the Company’s intangible asset of Vicineum EU rights. The Company concluded that the carrying value of the Company’s intangible asset of Vicineum EU rights of $14.7 million was fully impaired and was reduced to zero in the second quarter of 2022.

Goodwill

Goodwill on the Company's condensed consolidated balance sheets is the result of the Viventia Acquisition in September 2016. During the second quarter of 2022, the Company observed continued trends in the Company’s market capitalization as compared to the carrying value of its single reporting unit as well as changes in certain assumptions in the fair value of the business including market share, size, length and cost of a clinical trial, and time to potential market launch. The Company identified these changes as potential impairment indicators and performed a quantitative impairment analysis, in advance of the Company's typical annual assessment date of October 1 and concluded that the carrying value of its goodwill of $13.1 million was fully impaired and was reduced to zero in the second quarter of 2022.

The following table sets forth a summary of the change in goodwill as of September 30, 2022 and December 31, 2021 (in thousands).


Balance at December 31, 2021	$	13,064
Impairment loss	(13,064)
Balance at September 30, 2022	$	—

ACCRUED EXPENSES

9 Months Ended

Sep. 30, 2022

Payables and Accruals [Abstract]

ACCRUED EXPENSES

The following table sets forth the composition of accrued expenses as of September 30, 2022 and December 31, 2021 (in thousands):


	September 30, 2022		December 31, 2021
Research and development	$	1,242	$	1,841
Payroll-related expenses	2,043		2,967
Restructuring charge related	6,365		1,497
Professional fees	381		597
Legal expenses, including preliminary litigation settlement	23,720		1,344
Other	49		9
Total Accrued Expenses	$	33,800	$	8,255

COMMITMENTS AND CONTINGENCIES	9 Months Ended
COMMITMENTS AND CONTINGENCIES	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Legal Proceedings From time to time, the Company may become subject to legal proceedings, claims, and litigation arising in the ordinary course of business. When the Company becomes aware of a claim or potential claim, it assesses the likelihood of any loss or exposure. In accordance with authoritative guidance, the Company records loss contingencies in its financial statements only for matters in which losses are probable and can be reasonably estimated. Where a range of loss can be reasonably estimated with no best estimate in the range, the Company records the minimum estimated liability. If the loss is not probable or the amount of the loss cannot be reasonably estimated, the Company discloses the nature of the specific claim if the likelihood of a potential loss is reasonably possible, and the amount involved is material. The Company continuously assesses the potential liability related to the Company’s pending litigation and revises its estimates when additional information becomes available. The Company is not currently a party to any material legal proceedings, other than as described below. On August 19, 2021, August 31, 2021, and October 7, 2021, three substantially identical securities class action lawsuits captioned Bibb v. Sesen Bio, Inc., et. al., Case No. 1:21-cv-07025, Cizek v. Sesen Bio, Inc., et. al., Case No. 1:21-cv-07309, and Markman v. Sesen Bio, Inc. et al., Case No. 1:21-cv-08308 were filed against the Company and certain of its officers in the US District Court for the Southern District of New York. The three complaints alleged violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder based on statements made by the Company concerning its BLA for Vicineum for the treatment of BCG-unresponsive NMIBC. The three complaints sought compensatory damages and costs and expenses, including attorneys’ fees. On October 29, 2021, the court consolidated the three cases under the caption In re Sesen Bio, Inc. Securities Litigation, Master File No. 1:21-cv-07025-AKH (the “Securities Litigation”), and appointed Ryan Bibb, Rodney Samaan, Lionel Dreshaj and Benjamin Dreshaj (collectively, the “Lead Plaintiffs”) collectively as the lead plaintiffs under the Private Securities Litigation Reform Act. On November 1, 2021, two stockholders filed motions to reconsider asking the court to appoint a different lead plaintiff. On November 24, 2021, defendants filed a motion to transfer venue to the US District Court for the District of Massachusetts. That motion was fully briefed as of December 13, 2021, but the court has not ruled on that motion. On December 6, 2021, the Lead Plaintiffs filed an amended class action complaint (the “Amended Complaint”). The Amended Complaint alleges the same violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder on the same theory as the prior complaints. The defendants moved to dismiss the Amended Complaint on March 7, 2022, and that motion was fully briefed on May 6, 2022. On June 3, 2022, before the court ruled on the motion to dismiss, the parties requested that the court hold any decision on the motion to dismiss in abeyance to provide the parties with an opportunity to engage in mediation. On June 30, 2022 and July 6, 2022, the Company and the plaintiffs engaged in mediation sessions in an attempt to resolve the Securities Litigation and continued to discuss a potential settlement over the following weeks. On July 19, 2022, the parties reached an agreement in principle to settle the Securities Litigation. Pursuant to that agreement, the Company and the individual defendants will pay or cause to be paid to members of the class who submit timely and valid proofs of claims. In exchange, the Lead Plaintiffs will dismiss the action and all class members who do not timely and validly opt-out of the settlement will provide broad customary releases to the Company and the individual defendants. On August 3, 2022, the parties entered into a Stipulation and Agreement of Settlement to settle the Securities Litigation, which was filed with the court on August 17, 2022. The Stipulation and Agreement of Settlement related to the Securities Litigation provides for a settlement payment of $21.0 million to the class and the dismissal of all claims against the Company and the other defendants. The settlement payment is being funded by the Company and its insurance carriers. On September 1, 2022, the US District Court for the Southern District of New York issued an order denying the motions to appoint a different lead plaintiff. On September 28, 2022, the court issued an order granting preliminary approval of the proposed settlement of the Securities Litigation. The court has set a final settlement approval hearing for January 23, 2023 at 10:00 a.m. local time. On September 20, 2021 and September 24, 2021, two substantially similar derivative lawsuits captioned Myers v. Sesen Bio, Inc., et. al., Case No. 1:21-cv-11538 and D’Arcy v. Sesen Bio, Inc., et. al., Case No. 1:21-cv-11577 were filed against the Company’s board of directors and certain of its officers in the US District Court for the District of Massachusetts, with the Company named as nominal defendant. On January 12, 2022, a third derivative complaint captioned Tang v. Sesen Bio, Inc., et al., was filed in Superior Court in Massachusetts against the Company’s board of directors and certain of its officers (the “State Derivative Litigation”). The three derivative complaints allege breach of fiduciary duties, waste of corporate assets, and violations of federal securities laws based on statements made by the Company concerning its BLA for Vicineum for the treatment of BCG-unresponsive NMIBC. The D’Arcy complaint further alleges unjust enrichment, abuse of control, gross mismanagement and aiding and abetting thereof. The three derivative complaints seek unspecified damages, restitution and disgorgement of profits, benefits and compensation obtained by the defendants and costs and expenses, including attorneys’ fees. On October 18, 2021, the court consolidated the two federal court cases under the caption In re Sesen Bio, Inc. Derivative Litigation, Lead Case No. 1:21-cv-11538 (the “Federal Derivative Litigation”). On December 22, 2021, the court entered a joint stipulation among the parties to stay the Federal Derivative Litigation until after a ruling on any motion to dismiss filed by defendants in the Securities Litigation. On May 1, 2022, the plaintiffs filed a verified consolidated shareholder derivative complaint in the Federal Derivative Litigation. On May 18, 2022, the court entered a joint stipulation among the parties to stay the State Derivative Litigation until after a ruling on any motion to dismiss filed by defendants in the Securities Litigation. On July 6, 2022, the Company and the plaintiffs to the Federal Derivative Litigation and the State Derivative Litigation engaged in mediation in an attempt to resolve the litigation, with settlement discussions continuing over the following days. On July 19, 2002, the parties reached an agreement in principle to settle the Federal Derivative Litigation, the State Derivative Litigation and other potential related derivative claims (collectively, the “Derivative Litigation”). Pursuant to that agreement, the individual defendants will cause the Company to adopt certain enhancements to its corporate governance policies and procedures. In exchange, plaintiffs will dismiss the Derivative Litigation and, on behalf of the Company, provide broad customary releases to the individual defendants. On August 22, 2002, the parties entered into a Stipulation of Settlement to settle the Derivative Litigation, which was filed with the court on August 30, 2022. The Stipulation of Settlement related to the Derivative Litigation confirms that the Company previously adopted certain corporate governance enhancements in response to, among other things, the filing of the Derivative Litigation, and that, subject to final court approval, the Company will adopt additional corporate governance enhancements. The Stipulation of Settlement also provides for a $0.6 million payment for plaintiffs’ attorneys fees due to the benefits the corporate governance enhancements are intended to provide to the Company. The payment of plaintiffs’ attorneys fees is being funded by the Company. On September 2, 2022, the court issued an order granting preliminary approval of the Stipulation of Settlement related to the Derivative Litigation. The court has set a final settlement approval hearing for November 8, 2022 at 2:00 p.m. local time. During the second quarter of 2022, the Company deemed the settlements of the Securities Litigation and the Derivative Litigation probable and amounts reasonably estimable and recorded $21.6 million to litigation related liability. During the third quarter of 2022, the Company paid $0.6 million to be held in escrow for the plaintiffs' attorneys fees and $21.0 million remains as a litigation related liability as of September 30, 2022. The Company, its board of directors and the individual defendants continue to deny all allegations of any wrongdoing but are seeking to settle the Securities Litigation and the Derivative Litigation to avoid the uncertainty, risk, expense and distraction of protracted litigation. Subsequent to September 30, 2022, on October 21, 2022, the Company received two separate letters and on November 4, 2022, the Company received one letter from purported stockholders demanding that the Company amend the Registration Statement filed with the SEC on October 14, 2022 (the “Registration Statement”) to provide additional disclosures that such stockholders allege were improperly omitted from the Registration Statement, including information regarding the financial projections for Carisma, the financial analyses performed by the Company’s financial advisor in support of its fairness opinion, and the background and process leading to the execution of the Merger Agreement. The Company believes that these demands are without merit and intends to vigorously defend against them. See discussion in Note 19. “Subsequent Events.” Executive Employment Agreements The Company has entered into employment agreements or offer letters with certain of its key executives, providing for separation payments and benefits in certain circumstances, as defined in the agreements. Termination Fees associated with the Anticipated Merger with Carisma The Merger Agreement contains certain termination rights of each of the Company and Carisma. Upon termination of the Merger Agreement under specified circumstances, the Company may be required to pay Carisma a termination fee of $7.6 million and/or reimburse Carisma’s expenses up to a maximum of $1.75 million, and Carisma may be required to pay the Company a termination fee of $5.49 million and/or reimburse the Company expenses up to a maximum of $1.75 million. At this time, no assessment can be made as to the likely outcome or whether the outcome will be material to the Company

LEASES	9 Months Ended
LEASES	Sep. 30, 2022
Leases [Abstract]
LEASES	LEASES During the third quarter of 2022, the Company entered into a Lease Termination Agreement (the “Lease Termination Agreement”) pursuant to which the Company terminated its operating lease agreement for its 31,000 square foot facility in Winnipeg, Manitoba which consists of manufacturing, laboratory, warehouse, and office space and agreed to end the lease by September 30, 2022. As part of the execution of the Lease Termination Agreement, the Company paid the landlord the all-inclusive sum of CAD $1.2 million (USD $0.9 million). Operating lease costs under this lease, including the related operating costs, were $81,000 and $245,000 for the three and nine months ended September 30, 2022, respectively, and $79,000 and $245,000 for the three and nine months ended September 30, 2021, respectively. The right of use asset total was zero as of September 30, 2022 and $123,300 as of December 31, 2021. As of December 31, 2021, the asset component of the Company’s operating leases was recorded as operating lease right-of-use assets and reported within other assets on the Company's condensed consolidated balance sheets. The short-term lease liability was zero as of September 30, 2022 and $123,300 as of December 31, 2021. As of December 31, 2021, the short-term lease liability was recorded in other current liabilities on the Company’s condensed consolidated balance sheets. There was no long-term operating lease liability as of September 30, 2022 or December 31, 2021. Operating lease cost is recognized on a straight-line basis over the term of the lease. In addition, the Company has short-term property leases for modular office space for 1) its corporate headquarters in Cambridge, MA and 2) office space in Philadelphia, PA. The Company intends to terminate both leases in connection with the closing of the anticipated Merger with Carisma. The short-term lease in Philadelphia is renewed on a month-to-month basis. The short-term lease in Cambridge ends in June 2023. The minimum monthly rent for these office spaces is $2,500 and $17,200, respectively, which is subject to change if and as the Company adds space to or deducts space from the leases.

STOCKHOLDERS' EQUITY

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

STOCKHOLDERS' EQUITY

Equity Financings

ATM Offering

The Company has entered into an Open Market Sale Agreement SM with Jefferies LLC ("Jefferies"), dated November 29, 2019, as amended by Amendment No. 1 dated October 30, 2020, Amendment No. 2 dated February 17, 2021 and Amendment No. 3, dated June 1, 2021 (as amended, the "Sale Agreement"), under which the Company may issue and sell shares of its common stock, par value $0.001 per share, from time to time through Jefferies (the “ATM Offering”). In June and July 2021, the Company filed prospectus supplements with the SEC in connection with the offer and sale of up to an aggregate of $200 million of common stock pursuant to the Sale Agreement of which $97.8 million of common stock remain available for future issuance as of September 30, 2022. Sales of common stock under the Sale Agreement are made by any method that is deemed to be an ATM offering as defined in Rule 415(a)(4) of the Securities Act of 1933, as amended, including but not limited to sales made directly on or through the Nasdaq Stock Market or any other existing trading market for the Company's common stock. The Company may sell shares of its common stock efficiently from time to time but has no obligation to sell any of its common stock and may at any time suspend offers under the Sale Agreement or terminate the Sale Agreement. Subject to the terms and conditions of the Sale Agreement, Jefferies will use its commercially reasonable efforts to sell common stock from time to time, as the sales agent, based upon the Company’s instructions, which include a prohibition on sales below a minimum price set by the Company from time to time. The Company has provided Jefferies with customary indemnification rights, and Jefferies is entitled to a commission at a fixed rate equal to 3.0% of the gross proceeds for each sale of common stock under the Sale Agreement. The Company did not sell any shares of common stock pursuant to the Sale Agreement during the nine months ended September 30, 2022. The Company raised $175.0 million of net proceeds from the sale of 56.9 million shares of common stock at a weighted-average price of $3.17 per share during the nine months ended September 30, 2021. The Company raised $38.2 million of net proceeds from the sale of 9.8 million shares of common stock at a weighted-average price of $4.01 per share during the three months ended September 30, 2021. Share issuance costs, including sales agent commissions, related to the ATM Offering totaled $1.2 million and $5.4 million during the three and nine months ended September 30, 2021, respectively.

Preferred Stock

Pursuant to its Amended and Restated Certificate of Incorporation (the "Certificate of Incorporation"), the Company is authorized to issue 5.0 million shares of "blank check" preferred stock, $0.001 par value per share, which enables its board of directors, from time to time, to create one or more series of preferred stock. Each series of preferred stock issued shall have the rights, preferences, privileges and restrictions as designated by the board of directors. The issuance of any series of preferred stock could affect, among other things, the dividend, voting and liquidation rights of the Company's common stock. The Company had no preferred stock issued and outstanding as of September 30, 2022 and 2021.

Common Stock

Following approval by the Company’s stockholders on May 3, 2021, an amendment became effective to the Certificate of Incorporation that increased the number of authorized shares of common stock from 200 million to 400 million, of which approximately 203 million and 199 million shares were issued and outstanding as of September 30, 2022 and December 31, 2021, respectively. In addition, the Company had reserved for issuance the following amounts of shares of its common stock for the purposes described below as of September 30, 2022 and December 31, 2021 (in thousands):


	September 30, 2022	December 31, 2021
Shares of common stock issued	202,757	199,464
Shares of common stock reserved for issuance for:
Warrants	199	199
Stock options	16,202	15,703
Restricted stock units	4,695	3,041
Shares available for grant under 2014 Stock Incentive Plan	3,725	8,933
Shares available for sale under 2014 Employee Stock Purchase Plan	2,300	2,300
Total shares of common stock issued and reserved for issuance	229,878	229,640

The voting, dividend and liquidation rights of holders of shares of common stock are subject to and qualified by the rights, powers and preferences of holders of shares of preferred stock. Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company's stockholders; provided, however, that, except as otherwise required by law, holders of common stock shall not be entitled to vote on any amendment to the Company’s Certificate of Incorporation that relates solely to the terms of one or more outstanding series of preferred stock if the holders of such affected series are entitled, either separately or together as a class with the holders of one or more such series, to vote thereon. There shall be no cumulative voting.

Dividends may be declared and paid on the common stock from funds lawfully available thereof as and when determined by the board of directors and subject to any preferential dividend or other rights of any then-outstanding preferred stock. The Company has never declared or paid, and for the foreseeable future does not expect to declare or pay, dividends on its common stock, other than the CVR (as further described in Note 17. “License Agreements” below) and any special cash dividend that the Company may pay to its stockholders in connection with the consummation of the Merger.

Upon the dissolution or liquidation of the Company, whether voluntary or involuntary, holders of common stock will be entitled to receive all assets of the Company available for distribution to its stockholders, subject to any preferential or other rights of any then-outstanding preferred stock.

Warrants

All of the Company’s outstanding warrants are non-tradeable and equity-classified because they meet the derivative scope exception under ASC Topic 815-40, Derivatives and Hedging - Contracts in Entity’s Own Equity. The following table sets forth the Company's warrant activity for the three months ended September 30, 2022 (in thousands):


Issued	Exercise Price	Expiration	December 31, 2021	Issued	(Exercised)	(Cancelled)	September 30, 2022
Mar-2018	$0.55*	Mar-2023	132	—	—	—	132
Nov-2017	$0.55*	Nov-2022	12	—	—	—	12
May-2015	$11.83	Nov-2024	28	—	—	—	28
Nov-2014	$11.04	Nov-2024	27	—	—	—	27
			199	—	—	—	199

*Exercise price shown (i) reflects modification and (ii) is subject to further adjustment based on down round provision added by amendment described in “Item 15. Exhibits and Financial Statement Schedules - Note 12. Stockholders’ Equity (Deficit)” in the audited annual consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2021.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126731327&loc=SL126733271-114008

+ Details

EARNINGS (LOSS) PER SHARE

9 Months Ended

Sep. 30, 2022

Earnings Per Share [Abstract]

EARNINGS (LOSS) PER SHARE

EARNINGS (LOSS) PER SHAREA net loss cannot be diluted. Therefore, when the Company is in a net loss position, basic and diluted loss per common share are the same. If the Company achieves profitability, the denominator of a diluted earnings per common share calculation includes both the weighted-average number of shares outstanding and the number of common stock equivalents, if the inclusion of such common stock equivalents would be dilutive. Dilutive common stock equivalents potentially include warrants, stock

options and unvested restricted stock awards and units using the treasury stock method, along with the effect, if any, from outstanding convertible securities. The majority of the Company’s outstanding warrants to purchase common stock have participation rights to any dividends that may be declared in the future and are therefore considered to be participating securities. Participating securities have the effect of diluting both basic and diluted earnings per share during periods of income. During periods of loss, no loss is allocated to the participating securities since the holders have no contractual obligation to share in the losses of the Company.

Additionally, an entity that presents earnings per share shall recognize the value of the effect of an anti-dilution provision in an equity-classified freestanding financial instrument in the period the anti-dilution provision is triggered. That effect shall be treated as a deemed dividend and as a reduction of income available to common stockholders in basic earnings per share. The deemed dividend is added back to income available to common stockholders when applying the treasury stock method for diluted earnings per share.

For periods with net income, diluted net earnings per share is calculated by either (i) adjusting the weighted-average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period as determined using the treasury stock method or (ii) the two-class method considering common stock equivalents, whichever is more dilutive. The two-class method is an earnings allocation formula that treats a participating security as having rights to earnings that otherwise would have been available to common stockholders. Accordingly, the Company applied the two-class method to calculate basic and diluted net earnings per share of common stock for the three months ended September 30, 2022 and September 30, 2021.

For purposes of the diluted net loss per share calculation, common stock equivalents are excluded from the calculation if their effect would be anti-dilutive.

The following table illustrates the determination of earnings (loss) per share for each period presented:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
	(in thousands, except per share amounts)
Basic Earnings (Loss) Per Share:
Numerator:
Net income (loss)	$	20,457	$	71,674	$	(12,310)	$	(9,280)

Less: Income attributable to participating securities - basic	(15)		(52)		—		—
Net income (loss) attributable to common stockholders - basic	$	20,442	$	71,622	$	(12,310)	$	(9,280)

Denominator:
Weighted average common shares outstanding - basic	200,464		196,778		199,801		176,547
Net income (loss) per share applicable to common stockholders - basic	$	0.10	$	0.36	$	(0.06)	$	(0.05)

Dilutive Earnings (Loss) Per Share:
Numerator:
Net income (loss)	$	20,457	$	71,674	$	(12,310)	$	(9,280)

Less: Income attributable to participating securities - diluted	(15)		(51)		—		—
Net income (loss) attributable to common stockholders - diluted	$	20,442	$	71,623	$	(12,310)	$	(9,280)

Denominator:
Weighted average shares outstanding	200,464		196,778		199,801		176,547

Dilutive impact from:
Stock options and employee stock purchase plan	20		4,239		—		—
Restricted stock units & performance based stock units	463		—		—		—
Weighted average common shares outstanding - diluted	200,947		201,017		199,801		176,547
Net income (loss) per share applicable to common stockholders - diluted	$	0.10	$	0.36	$	(0.06)	$	(0.05)

The following potentially dilutive securities outstanding as of September 30, 2022 and 2021 have been excluded from the denominator of the diluted loss per share of common stock outstanding calculation (in thousands):


	Three Months Ended September 30,		Nine Months Ended September 30,
	2022	2021	2022	2021
Warrants	55	55	199	199
Stock options	16,182	11,273	16,202	15,511
RSUs and PSUs	4,232	—	4,695	—
Total	20,469	11,328	21,096	15,710

SHARE-BASED COMPENSATION

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

SHARE-BASED COMPENSATION

The following table sets forth the amount of share-based compensation expense recognized by the Company by line item on its Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2022 and 2021 (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development	$	863	$	152	$	1,838	$	536
General and administrative	1,305		1,016		4,026		2,849
Total Share Based Compensation	$	2,168	$	1,168	$	5,864	$	3,385

2014 Stock Incentive Plan

The Company's 2014 Stock Incentive Plan, as amended (the "2014 Plan"), was adopted by its board of directors in December 2013 and subsequently approved by its stockholders in January 2014. The 2014 Plan became effective immediately prior to the closing of the Company's IPO in February 2014 and provides for the grant of incentive and non-qualified stock options, restricted stock awards, restricted stock units ("RSU"), stock appreciation rights and other stock-based awards, with amounts and terms of grants determined by the Company's board of directors at the time of grant, to the Company's employees, officers, directors, consultants and advisors.

At the Annual Meeting of the Company's stockholders in June 2019, the Company's stockholders approved an amendment to the 2014 Plan that (i) increased by 7.9 million the number of shares of common stock reserved for issuance under the 2014 Plan and (ii) eliminated the “evergreen” or automatic replenishment provision of the 2014 Plan, pursuant to which the number of shares of common stock authorized for issuance under the 2014 Plan was automatically increased on an annual basis. At the Annual Meeting of the Company’s stockholders in May 2021, the Company’s stockholders approved an amendment to the 2014 Plan that increased by 12 million the number of shares of common stock reserved for issuance under the 2014 Plan. There were approximately 3.7 million shares of common stock available for issuance under the 2014 Plan as of September 30, 2022.

Stock options outstanding under the 2014 Plan generally vest over a four-year period at the rate of 25% of the grant vesting on the first anniversary of the date of grant and 6.25% of the grant vesting at the end of each successive three-month period thereafter. Stock options granted under the 2014 Plan are exercisable for a period of ten years from the date of grant. There were approximately 13.0 million stock options outstanding under the 2014 Plan as of September 30, 2022.

On September 9, 2021, the Company’s board of directors and the compensation committee of the board of directors (the “Compensation Committee”) approved a retention program for all then-current employees, except for the Chief Executive Officer, pursuant to which the Company will provide certain incentives designed to retain such employees (the “2021 Retention Program”). Pursuant to the 2021 Retention Program and effective as of October 1, 2021, the Company’s non-executive employees received a combination of a cash bonus award and a one-time RSU award which vested in full on September 30, 2022, subject to continued employment through September 30, 2022. Each RSU represents a contingent right to receive one share of the Company’s common stock.

Also pursuant to the 2021 Retention Program and effective as of October 1, 2021, the Company’s executive officers, except for the Chief Executive Officer, were granted a one-time performance-based restricted stock unit (“PSU”) award equal to the value of approximately fifty percent of then-current base salary. The fair value of PSUs at the grant date was $0.4 million. Each PSU represents a contingent right to receive one share of the Company’s common stock upon the satisfaction of pre-determined performance criteria. Subject to continued employment, such awards vest on September 30, 2023 upon the determination by the Compensation Committee of the level of achievement of certain key milestones consisting of a clinical trial milestone, an employee retention milestone and cash management milestones. As of September 30, 2022, achievement was deemed probable for only the cash management milestone, representing $87,000, 20% of the PSU awards. Therefore, $11,000 and $44,000 have been expensed during the three and nine months ended September 30, 2022, respectively and $43,000 remains measured but unrecognized.

2009 Stock Incentive Plan

The Company maintains a 2009 Stock Incentive Plan, as amended and restated (the "2009 Plan"), which provided for the grant of incentive and non-qualified stock options and restricted stock awards and restricted stock units, with amounts and terms of grants determined by the Company's board of directors at the time of grant, to its employees, officers, directors, consultants and advisors. Upon the closing of its IPO in February 2014, the Company ceased granting awards under the 2009 Plan and all

shares (i) available for issuance under the 2009 Plan at such time and (ii) subject to outstanding awards under the 2009 Plan that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased without having been fully exercised or resulting in any common stock being issued were carried over to the 2014 Plan. Stock options granted under the 2009 Plan are exercisable for a period of ten years from the date of grant. There were approximately 0.1 million fully vested stock options outstanding under the 2009 Plan as of September 30, 2022.

Out-of-Plan Inducement Grants

From time to time, the Company has granted equity awards to its newly hired employees, including executives, in accordance with Nasdaq employment inducement grant exemption (Nasdaq Listing Rule 5635(c)(4)). Such grants are made outside of the 2014 Plan and act as an inducement material to the employee's acceptance of employment with the Company. There were approximately 3.1 million stock options outstanding which were granted as employment inducement awards outside of the 2014 Plan as of September 30, 2022.

Stock Options

The following table sets forth a summary of the Company’s total stock option activity, including awards granted under the 2014 Plan and the 2009 Plan and inducement grants made outside of stockholder approved plans, for the nine months ended September 30, 2022:


	Number of Shares under Option (in thousands)	Weighted-Average Exercise Price	Weighted-Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2021	15,703	$1.93	8.03	$	82
Granted	1,510	$0.72
Exercised	—	—
Canceled or forfeited	(1,011)	2.10
Outstanding at September 30, 2022	16,202	$1.81	7.41	DM
Exercisable at September 30, 2022	10,494	$1.72	6.94	DM

The Company recognized share-based compensation expense, related to stock options, of $1.0 million and $3.5 million for the three and nine months ended September 30, 2022, respectively and $1.2 million and $3.4 million for the three and nine months ended September 30, 2021, respectively. As of September 30, 2022, there was $6.4 million of total unrecognized compensation cost related to unvested stock options which the Company expects to recognize over a weighted-average period of 2.09 years. The weighted-average grant-date fair value of stock options granted during the nine months ended September 30, 2022 and 2021 were $0.46 and $2.20, respectively. No stock options were exercised during the nine months ended September 30, 2022.

For the nine months ended September 30, 2022 and 2021, the grant-date fair value of stock options was determined using the following weighted-average inputs and assumptions in the Black-Scholes option pricing model:


	September 30, 2022	September 30, 2021
Fair market value	$0.72	$3.40
Grant exercise price	$0.72	$3.40
Expected term (in years)	6.0	6.03
Risk-free interest rate	2.1%	0.9%
Expected volatility	71.8%	74.6%
Dividend yield	—%	—%

Restricted Stock Units and Performance Stock Units

The following table sets forth a summary of the Company's RSU and PSU activity for the nine months ended September 30, 2022:


	Restricted Stock Units (in thousands)	Weighted Average Grant Date Fair Value
Unvested at December 31, 2021	3,041	$0.80
Granted RSU	4,160	$0.68
Cancelled RSU	(217)	$0.75
Released RSU	(3,293)	$0.76
Granted PSU	1,004	$0.67
Unvested at September 30, 2022	4,695	$0.68

The Company did not grant any RSUs or PSUs during the nine months ended September 30, 2021.

The share-based compensation expense related to RSUs and PSUs for the three and nine months ended September 30, 2022 was $1.2 million and $2.4 million, respectively. There was no shared-based compensation expense related to RSUs and PSUs for the three and nine months ended September 30, 2021. As of September 30, 2022, there was $1.8 million of total unrecognized compensation cost related to unvested RSUs and PSUs.

EMPLOYEE BENEFIT PLANS	9 Months Ended
EMPLOYEE BENEFIT PLANS	Sep. 30, 2022
Retirement Benefits [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS 2014 Employee Stock Purchase Plan The Company's 2014 Employee Stock Purchase Plan ("2014 ESPP") was adopted by its board of directors in December 2013 and subsequently approved by its stockholders in January 2014. The 2014 ESPP became effective immediately prior to the closing of the Company's IPO in February 2014 and established an initial reserve of 0.2 million shares of the Company's common stock for issuance to participating employees. At the Annual Meeting of the Company's stockholders in May 2021, the Company's stockholders approved an amendment to the 2014 ESPP that increased by 2.3 million the number of shares of common stock reserved for issuance under the 2014 ESPP. The purpose of the 2014 ESPP is to enhance employee interest in the success and progress of the Company by encouraging employee ownership of common stock of the Company. The 2014 ESPP provides employees with the opportunity to purchase shares of common stock at a 15% discount to the market price through payroll deductions or lump sum cash investments. The Company estimates the number of shares to be issued at the end of an offering period and recognizes expense over the requisite service period. Shares of the common stock issued and sold pursuant to the 2014 ESPP are shown on the condensed consolidated statements of changes in stockholders' equity (deficit). As of September 30, 2022, there were 2.3 million shares of common stock available for sale under the 2014 ESPP. The Company did not sell any shares under the ESPP during the nine months ended September 30, 2022 and 2021. Defined Contribution Plans United States - 401(k) Plan The Company maintains a 401(k) defined contribution retirement plan which covers all of its US employees. Employees are eligible to participate on the first of the month following their date of hire. Under the 401(k) plan, participating employees may defer up to 100% of their pre-tax salary, subject to certain statutory limitations. Employee contributions vest immediately. The plan allows for a discretionary match per participating employee up to a maximum of $4,000 per year. The expenses incurred for the periods presented were de minimis amount for each of the nine months ended September 30, 2022 and 2021, respectively. Canada - Defined Contribution Plan The Company maintains a defined contribution plan for its Canadian employees. Participants may contribute a percentage of their annual compensation to this plan, subject to statutory limitations. The Company contributes up to the first 4% of eligible compensation for its Canadian-based employees to the retirement plan. The expenses incurred for the periods presented were de minimis amount for each of the nine months ended September 30, 2022 and 2021, respectively.

INCOME TAXES

9 Months Ended

Sep. 30, 2022

Income Tax Disclosure [Abstract]

INCOME TAXES

The following table sets forth the components of the Company's loss before income taxes by country (in thousands):


	Nine Months Ended September 30,
	2022		2021
Country:
United States	$	(32,083)	$	(38,864)
Canada	15,898		21,311
Total loss before income taxes	$	(16,185)	$	(17,553)

The Company's tax benefit (provision) is comprised of the following components (in thousands):


	Nine Months Ended September 30,
	2022		2021
Current tax benefit (provision)
Federal	$	—	$	8,559
State	—		—
Foreign	3,875		(286)
Total current benefit	$	3,875	$	8,273

The Company's deferred tax liability is comprised of the following:


	September 30, 2022		December 31, 2021
Deferred tax liabilities
IPR&D	$	—	$	(3,969)

Total deferred tax liabilities	$	—	$	(3,969)

For the nine months ended September 30, 2022, the Company recorded a benefit from income taxes of $3.9 million. In the second quarter of 2022, the Company determined that the fair value of the Vicineum EU rights was zero, which resulted in an impairment charge of $14.7 million. In connection with this impairment charge, the Company reversed the associated deferred tax liability by $4.0 million as an income tax benefit, partially offset by $0.1 million income tax paid to foreign jurisdictions pursuant to the Qilu License Agreement.

During the nine months ended September 30, 2021, the Company recorded a benefit from income taxes of $8.3 million. In the third quarter of 2021, the Company determined that the fair value of the Vicineum US rights was zero, which resulted in an impairment charge of $31.7 million. In connection with this impairment charge, in the third quarter of 2021, the Company wrote-down the associated deferred tax liability by $8.6 million as a benefit.

- Definition

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.

+ References

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

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

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

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

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

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

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

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-URI https://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

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

+ Details

LICENSE AGREEMENTS	9 Months Ended
LICENSE AGREEMENTS	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
LICENSE AGREEMENTS	LICENSE AGREEMENTS In-License Agreements License Agreement with Zurich The Company has a license agreement with the University of Zurich ("Zurich") which grants the Company exclusive license rights, with the right to sublicense, to make, have made, use and sell under certain patents primarily directed to the Company's targeting agent, including an EpCAM chimera and related immunoconjugates and methods of use and manufacture of the same (the “Zurich License Agreement”). These patents cover some key aspects of Vicineum. The Company's receipt of the Complete Response Letter ("CRL") regarding the BLA for Vicineum for the treatment of BCG-unresponsive NMIBC triggered a $0.5 million milestone payment to Zurich. Under the Zurich License Agreement, as of September 30, 2022, the Company is also obligated to pay up to a 4% royalty on the net product sales for products covered by or manufactured using a method covered by a valid claim in the Zurich patent rights, which includes Vicineum. Royalties owed to Zurich will be reduced if the total royalty rate owed by the Company to Zurich and any other third party is 10% or greater, provided that the royalty rate to Zurich may not be less than 2% of net sales. The obligation to pay royalties in a particular country expires upon the expiration or termination of the last of the Zurich patent rights that covers the manufacture, use or sale of a product. There is no obligation to pay royalties in a country if there is no valid claim that covers the product or a method of manufacturing the product. The Company recorded an expense of $0.3 million and $0.5 million related to meeting a development milestone, the submission of the Company’s BLA with the FDA in December 2020, in the fourth quarter of 2020, and a regulatory milestone, the Company’s receipt of the CRL from the FDA in August 2021, in the third quarter of 2021, respectively. License Agreement with Micromet The Company has a License Agreement with Micromet AG ("Micromet"), now part of Amgen, Inc., which grants it nonexclusive rights, with certain sublicense rights, for know-how and patents allowing exploitation of certain single chain antibody products (the “Micromet License Agreement”). These patents cover some key aspects of Vicineum. Under the terms of the Micromet License Agreement, as of September 30, 2022, the Company may be obligated to pay up to €2.4 million in milestone payments for the first product candidate that achieves applicable regulatory and sales-based development milestones (approximately $2.4 million at exchange rates in effect on September 30, 2022). The Company is also required to pay up to a 3.5% royalty on the net sales for products covered by the agreement, which includes Vicineum. The royalty rate owed to Micromet in a particular country will be reduced to 1.5% if there are no valid claims covering the product in that country. The obligation to pay royalties in a particular country expires upon the later of the expiration date of the last valid claim covering the product and the tenth anniversary of the first commercial sale of the product in such country. Finally, the Company is required to pay to Micromet an annual license maintenance fee of €50,000 (approximately $48,987 at exchange rates in effect as of September 30, 2022), that can be credited towards any royalty payment the Company owes to Micromet. The Company recorded an expense of €0.7 million ($0.9 million) related to achievement of a development milestone in the three months ended December 31, 2020, due to the submission of the Company's BLA for Vicineum with the FDA in December 2020. The Company recorded an expense of €0.5 million ($0.6 million) related to the submission of marketing authorization application (the “MAA”) to the European Medicines Agency (the “EMA”) for Vysyneum™ in the first quarter of 2021. Vysyneum is the proprietary brand name that was conditionally approved by the EMA for oportuzumab monatox in the EU. License Agreement with XOMA The Company has a license agreement with XOMA Ireland Limited ("XOMA") which grants it non-exclusive rights to certain XOMA patent rights and know-how related to certain expression technology, including plasmids, expression strains, plasmid maps and production systems (the “XOMA License Agreement”). These patents and related know-how cover some key aspects of Vicineum. Under the terms of the XOMA License Agreement, the Company is required to pay up to $0.25 million in milestone payments for a product candidate that incorporates know-how under the license and achieves applicable clinical development milestones. The Company is also required to pay a 2.5% royalty on the net sales for products incorporating XOMA’s technology, which includes Vicineum. The Company has the right to reduce the amount of royalties owed to XOMA on a country-by-country basis by the amount of royalties paid to other third parties, provided that the royalty rate to XOMA may not be less than 1.75% of net sales. In addition, the foregoing royalty rates are reduced by 50% with respect to products that are not covered by a valid patent claim in the country of sale. The obligation to pay royalties in a particular country expires upon the later of the expiration date of the last valid claim covering the product and the tenth anniversary of the first commercial sale of the product in such country. Out-License Agreements Roche License Agreement In June 2016, the Company entered into the license agreement with Roche (the “Roche License Agreement”), pursuant to which the Company granted Roche an exclusive, worldwide license, including the right to sublicense, to its patent rights and know-how related to the Company’s monoclonal antibody EBI-031 and all other IL-6 antagonist monoclonal antibody technology owned by the Company (collectively, the "Roche Licensed Intellectual Property"). Under the Roche License Agreement, Roche was required to continue developing, at its cost, EBI-031 and any other product made from the Roche Licensed Intellectual Property that contains an IL-6 antagonist monoclonal antibody and pursue ongoing patent prosecution, at its cost. For additional information regarding the Roche License Agreement, see Note 17. “License Agreements” in the Notes to Condensed Consolidated Financial Statements in the Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2022. On July 15, 2022, the Company entered into an asset purchase agreement with Roche (the “Roche Asset Purchase Agreement”) pursuant to which Roche purchased all patent rights and know-how related to the monoclonal antibody EBI-031 and all other IL-6 antagonist monoclonal antibody technology owned by the Company for up to $70 million. As a result of the Roche Asset Purchase Agreement, the Roche License Agreement was terminated resulting in no further diligence, milestone or royalty payment obligations under the Roche License Agreement. Pursuant to the Roche Asset Purchase Agreement, Roche made a $40 million payment to the Company upon execution of the Roche Asset Purchase Agreement, which was recorded as license revenue in the third quarter of 2022. The Roche Asset Purchase Agreement also provides that Roche will make an additional $30 million payment to the Company upon Roche’s initiation of a Phase 3 clinical trial with EBI-031 for a defined indication if initiated prior to December 31, 2026. Pursuant to ASC 606, the variable consideration of $30 million is constrained. Therefore, the amount was not recorded as revenue during the third quarter of 2022. Additionally, at or prior to the effective time of the Merger, the Company will enter into a Contingent Value Rights Agreement (the “CVR Agreement”) with a rights agent (“Rights Agent”) pursuant to which the Company intends to declare a dividend payable to the Company’s stockholders of record as of a date agreed to by the Company and Carisma prior to the effective time of the Merger with respect to the receipt of one contingent value right (each, a “CVR”) for each outstanding share of the Company’s common stock held by such stockholders on such date. Each CVR will represent the contractual right to receive contingent cash payments upon the receipt by the Company of certain proceeds payable by Roche, if any, pursuant to the Roche Asset Purchase Agreement, upon the achievement by Roche of a specified milestone set forth in the Roche Asset Purchase Agreement, subject to certain customary deductions, including for expenses and taxes. The contingent payments under the CVR Agreement, if they become due, will be payable to the Rights Agent for subsequent distribution to the holders of the CVRs. In the event that no such proceeds are received, holders of the CVRs will not receive any payment pursuant to the CVR Agreement. There can be no assurance that any cash payment will be made or that any holders of CVRs will receive any amounts with respect thereto. OUS Business Development Partnership Agreements Qilu License Agreement On July 30, 2020, the Company and its wholly-owned subsidiary, Viventia Bio, Inc., entered into the Qilu License Agreement pursuant to which the Company granted Qilu an exclusive, sublicensable, royalty-bearing license, under certain intellectual property owned or exclusively licensed by the Company, to develop, manufacture and commercialize Vicineum (the “Qilu Licensed Product”) for the treatment of NMIBC and other types of cancer (the “Field”) in China, Hong Kong, Macau and Taiwan ("Greater China”). The Company also granted Qilu a non-exclusive, sublicensable, royalty-bearing sublicense, under certain other intellectual property licensed by the Company to develop, manufacture and commercialize the Qilu Licensed Product in Greater China. The Company retains (i) development, and commercialization rights in the rest of the world, excluding Greater China and (ii) manufacturing rights with respect to Vicineum in the rest of the world, excluding China. In consideration for the rights granted by the Company, Qilu agreed to pay to the Company a one-time upfront cash payment of $12 million, and milestone payments totaling up to $23 million upon the achievement of certain technology transfer, development and regulatory milestones. All payments were to be inclusive of VAT, which can be withheld by Qilu upon payment, and for which future recovery of such taxes may be available. Qilu also agreed to pay the Company a 12% royalty based upon annual net sales of Qilu Licensed Products in Greater China. The royalties are payable on a Qilu Licensed Product-by-Licensed Product and region-by-region basis commencing on the first commercial sale of a Qilu Licensed Product in a region and continuing until the latest of (i) twelve years after the first commercial sale of such Qilu Licensed Product in such region, (ii) the expiration of the last valid patent claim covering or claiming the composition of matter, method of treatment, or method of manufacture of such Qilu Licensed Product in such region, and (iii) the expiration of regulatory or data exclusivity for such Qilu Licensed Product in such region (collectively, the “Royalty Terms”). The royalty rate is subject to reduction under certain circumstances, including when there is no valid claim of a licensed patent that covers a Qilu Licensed Product in a particular region or no data or regulatory exclusivity of a Qilu Licensed Product in a particular region. Qilu is responsible for all costs related to developing, obtaining regulatory approval of and commercializing the Qilu Licensed Products in the Field in Greater China. Qilu is required to use commercially reasonable efforts to develop, seek regulatory approval for, and commercialize at least one Qilu Licensed Product in the Field in Greater China. A joint development committee was established between the Company and Qilu to coordinate and review the development, manufacturing and commercialization plans with respect to the Qilu Licensed Products in Greater China. The Company and Qilu also executed the terms and conditions of a supply agreement and related quality agreement pursuant to which the Company will manufacture or have manufactured and supply Qilu with all quantities of the Qilu Licensed Product necessary for Qilu to develop and commercialize the Qilu Licensed Product in the Field in Greater China until the Company has completed manufacturing technology transfer to Qilu and approval of a Qilu manufactured product by the National Medical Products Administration in China ("NMPA") for the Qilu Licensed Product has been obtained. The Qilu License Agreement will expire on a Qilu Licensed Product-by-Licensed Product and region-by-region basis on the date of the expiration of all applicable Royalty Terms. Either party may terminate the Qilu License Agreement for the other party’s material breach following a cure period or upon certain insolvency events. Qilu has the right to receive a refund of all amounts paid to the Company in the event the Qilu License Agreement is terminated under certain circumstances. The Qilu License Agreement includes customary representations and warranties, covenants and indemnification obligations for a transaction of this nature. The Qilu License Agreement is subject to the provisions of ASC Topic 606, Revenue. In 2020, the initial transaction price was estimated to be $11.2 million and was based on the up-front fixed consideration of $12 million less amounts withheld for VAT. The Company concluded that its agreements under the Qilu License Agreement represented one bundled performance obligation that had been achieved as of September 30, 2020. As such, $11.2 million of the total $11.2 million transaction price was considered earned and the Company recorded $11.2 million of revenue during the three-month period ended September 30, 2020. The Investigational New Drug application for Vicineum submitted by Qilu to the Center for Drug Evaluation of the NMPA was accepted for review in January 2021 and approved in March 2021, resulting in a $3 million milestone payment from Qilu, the first milestone payment out of the $23 million in potential milestone payments. The Company recorded $2.8 million (net of VAT) as license revenue during the three-month period ended March 31, 2021. The Company received the payment in 2021. In June 2021, the Qilu License Agreement was recognized by Shandong Province, Bureau of Science and Technology as a "Technology Transfer". An agreement that is designated as a Technology Transfer shall be entitled to a tax incentive of VAT recovery. As such, the Company recorded $0.9 million of revenue during the three months ended June 30, 2021 for additional purchase price resulting from Qilu's obligation to pay Sesen Bio an amount equal to its recovery of VAT. MENA License Agreement On November 30, 2020, the Company entered into a license agreement with a third party pursuant to which the Company granted an exclusive, sublicensable, royalty-bearing license, under certain intellectual property owned or exclusively licensed by the Company, to commercialize Vicineum in the Middle East and North Africa region (“MENA”) (the "MENA License Agreement"). In consideration for the rights granted by the Company, the counterparty to the MENA License Agreement agreed to pay to the Company an upfront payment of $3 million, which would be subject to certain tax withholdings. In addition, the counterparty agreed to pay to the Company milestone payments upon the achievement of certain sales-based milestones as well as a royalty based upon annual net sales in the MENA region for the term of the MENA License Agreement. On July 20, 2022, the Company provided notice of termination of the MENA License Agreement as a result of the Company’s strategic decision to voluntarily pause further development of Vicineum in the US. EIP License Agreement On August 5, 2021, the Company entered into an exclusive license agreement with EİP Eczacıbaşı İlaç Pazarlama A.Ş., (“EIP”) pursuant to which it granted EIP an exclusive license to register and commercialize Vicineum for the treatment of BCG-unresponsive NMIBC in Turkey and Northern Cyprus (the “EIP License Agreement"). Under the terms of the EIP License Agreement, the Company was entitled to receive an upfront payment of $1.5 million. The Company and EIP have amended the license agreement to defer EIP's payment of the upfront payment to coincide with the potential FDA approval of Vicineum. The Company would be eligible to receive additional regulatory and commercial milestone payments of $2.0 million and also to receive a 30% royalty on net sales in Turkey and Northern Cyprus. On July 20, 2022, the Company provided notice of termination of the EIP License Agreement as a result of the Company’s strategic decision to voluntarily pause further development of Vicineum in the US. The EIP License Agreement was terminated on October 20, 2022.

RESTRUCTURING AND RELATED ACTIVITIES

9 Months Ended

Sep. 30, 2022

Restructuring and Related Activities [Abstract]

RESTRUCTURING AND RELATED ACTIVITIES

On July 15, 2022, the Company approved a restructuring plan to reduce operating expenses and better align its workforce with the needs of its business following the decision to voluntarily pause further development of Vicineum in the US (the “2022 Restructuring Plan”). Execution of the 2022 Restructuring Plan is expected to be substantially completed in connection with the closing of the Merger with Carisma, which is expected to occur approximately two to three months from the date of this form 10-Q filing, November 7, 2022. The 2022 Restructuring Plan includes an incremental reduction in the Company’s workforce as well as additional cost-saving initiatives intended to preserve capital during the pendency of the Merger with Carisma and while the Company seeks a potential partner for the further development of Vicineum.

The Company also incurred one-time cash costs associated with the termination of certain contracts and all other activities under the 2022 Restructuring Plan. The following is a summary of accrued restructuring costs related to the 2022 Restructuring Plan, (in thousands):


	2022 Restructuring Plan
Severance and benefits costs	$	6,944
Contract termination and other associated costs	4,003
Total restructurings costs	10,947
Cash payments	(4,582)
Balance at September 30, 2022	$	6,365

Restructuring costs related to the Restructuring Plan were recorded in operating expenses in the Company’s Condensed Consolidated Statements of Income (Operations) and Comprehensive Income (Loss) in the three months ended September 30, 2022. The Company expects that substantially all of the accrued restructuring costs as of September 30, 2022 will be paid in cash in connection with the closing of the Merger with Carisma, which is expected to occur approximately two to three months from the date of this form 10-Q filing, November 7, 2022.

SUBSEQUENT EVENTS	9 Months Ended
SUBSEQUENT EVENTS	Sep. 30, 2022
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTSOn October 21, 2022, the Company received two separate letters and on November 4, 2022, the Company received one letter from purported stockholders demanding that the Company amend the Registration Statement filed with the SEC on October 14, 2022 to provide additional disclosures that such stockholders allege were improperly omitted from the Registration Statement, including information regarding the financial projections for Carisma, the financial analyses performed by the Company’s financial advisor in support of its fairness opinion, and the background and process leading to the execution of the Merger Agreement. The Company believes that these demands are without merit and intends to vigorously defend against them. At this time, no assessment can be made as to the likely outcome or whether the outcome will be material to the Company.

BASIS OF PRESENTATION (Policies)	9 Months Ended
BASIS OF PRESENTATION (Policies)	Sep. 30, 2022
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in accordance with GAAP and the rules and regulations of the SEC requires the use of estimates and assumptions, based on judgments considered reasonable, which affect the reported amounts of assets and liabilities and 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. The Company bases its estimates and assumptions on historical experience, known trends and events and various other factors that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Although management believes its estimates and assumptions are reasonable when made, they are based upon information available at the time they are made. Management evaluates the estimates and assumptions on an ongoing basis and, if necessary, makes adjustments. Due to the risks and uncertainties involved in the Company’s business and evolving market conditions, and given the subjective element of the estimates and assumptions made, actual results may differ from estimated results. The most significant estimates and judgments impact the fair value of intangible assets; goodwill and contingent consideration; income taxes (including the valuation allowance for deferred tax assets); and research and development expenses.
Principles of Consolidation	Principles of Consolidation The Company’s condensed consolidated financial statements include the accounts of the Company, its wholly owned subsidiaries Viventia and Seahawk Merger Sub, Inc. and its indirect subsidiary, Viventia Bio USA Inc. All intercompany transactions and balances have been eliminated in consolidation.
Foreign Currency Translation	Foreign Currency Translation The functional currency of the Company and each of its subsidiaries is the US dollar.
Recent Accounting Pronouncements	Adopted in 2022 In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity ("ASU 2020-06"). ASU 2020-06 simplifies the complexity associated with applying US GAAP for certain financial instruments with characteristics of both liability and equity. More specifically, the amendments focus on the guidance for convertible instruments and derivative scope exception for contracts in an entity’s own equity. The ASU also amends the diluted earnings per share ("EPS") guidance, including the requirement to use the if-converted method for all convertible instruments. ASU 2020-06 is effective for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021, and should be applied on a full or modified retrospective basis. The Company adopted this guidance on a modified retrospective basis effective January 1, 2022 and it did not have an impact on the Company's financial position, results of operations including per-share amounts, or cash flows. In May 2021, the FASB issued ASU No. 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options ("ASU 2021-04"). ASU 2021-04 clarifies and reduces diversity in an issuer’s accounting for modifications or exchanges of freestanding equity-classified written call options (for example, warrants) that remain equity classified after modification or exchange. ASU 2021-04 is effective for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021, and should be applied on a prospective basis. The Company adopted this guidance effective January 1, 2022 and it did not have an impact on the Company's financial position, results of operations including per-share amounts, or cash flows. Other recent accounting pronouncements issued, but not yet effective, are not expected to be applicable to the Company or have a material effect on the consolidated financial statements upon future adoption.
Fair Value Measurement	The carrying values of cash and cash equivalents, restricted cash, prepaid expenses and other current assets, and accounts payable on the Company’s condensed consolidated balance sheets approximated their fair values as of September 30, 2022 and December 31, 2021 due to their short-term nature. Certain of the Company’s financial instruments are measured at fair value using a three-level hierarchy that prioritizes the inputs used to measure fair value. This fair value hierarchy prioritizes the use of observable inputs and minimizes the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: Level 1: Inputs are quoted prices for identical instruments in active markets. Level 2: Inputs are quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; or model-derived valuations whose inputs are observable or whose significant value drivers are observable. Level 3: Inputs are unobservable and reflect the Company’s own assumptions, based on the best information available, including the Company’s own data.

FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS (Tables)

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

Schedule of Carrying Amounts and Fair Values of Financial Instruments Measured


	September 30, 2022
					Fair Value Measurement Based on
	Carrying Amount		Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Marketable securities:
Money market funds (cash equivalents)	$	11,450	$	11,450	$	11,450	$	—	$	—
Marketable securities	$	113,763	$	113,763	$	—	$	113,763	$	—
Liabilities:

Contingent consideration	$	—	$	—	$	—	$	—	$	—


	December 31, 2021
					Fair Value Measurement Based on
	Carrying Amount		Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Money market funds (cash equivalents)	$	16,382	$	16,382	$	16,382	$	—	$	—
Liabilities:

Contingent consideration	$	52,000	$	52,000	$	—	$	—	$	52,000

Schedule of Contingent Consideration Liability

The following table sets forth a summary of the change in the fair value of the Company's contingent consideration liability, measured on a recurring basis at each reporting period (in thousands).


Balance at December 31, 2021	$	52,000

Change in fair value of contingent consideration	(52,000)
Balance at September 30, 2022	$	—

INTANGIBLE ASSETS AND GOODWIL (Tables)

9 Months Ended

Sep. 30, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Composition of Intangible Assets

The following table sets forth the composition of intangible assets as of September 30, 2022 and December 31, 2021 (in thousands):


	September 30, 2022		December 31, 2021
IPR&D intangible assets:

Vicineum European Union rights	$	—	$	14,700
Total Intangibles	$	—	$	14,700

Schedule of Goodwill

The following table sets forth a summary of the change in goodwill as of September 30, 2022 and December 31, 2021 (in thousands).


Balance at December 31, 2021	$	13,064
Impairment loss	(13,064)
Balance at September 30, 2022	$	—

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

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+ Details

ACCRUED EXPENSES (Tables)

9 Months Ended

Sep. 30, 2022

Payables and Accruals [Abstract]

Schedule of Components of Accrued Expenses

The following table sets forth the composition of accrued expenses as of September 30, 2022 and December 31, 2021 (in thousands):


	September 30, 2022		December 31, 2021
Research and development	$	1,242	$	1,841
Payroll-related expenses	2,043		2,967
Restructuring charge related	6,365		1,497
Professional fees	381		597
Legal expenses, including preliminary litigation settlement	23,720		1,344
Other	49		9
Total Accrued Expenses	$	33,800	$	8,255

STOCKHOLDERS' EQUITY (Tables)

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

Schedule of Common Stock

In addition, the Company had reserved for issuance the following amounts of shares of its common stock for the purposes described below as of September 30, 2022 and December 31, 2021 (in thousands):


	September 30, 2022	December 31, 2021
Shares of common stock issued	202,757	199,464
Shares of common stock reserved for issuance for:
Warrants	199	199
Stock options	16,202	15,703
Restricted stock units	4,695	3,041
Shares available for grant under 2014 Stock Incentive Plan	3,725	8,933
Shares available for sale under 2014 Employee Stock Purchase Plan	2,300	2,300
Total shares of common stock issued and reserved for issuance	229,878	229,640

Schedule of Warrants Outstanding and Warrant Activity

The following table sets forth the Company's warrant activity for the three months ended September 30, 2022 (in thousands):


Issued	Exercise Price	Expiration	December 31, 2021	Issued	(Exercised)	(Cancelled)	September 30, 2022
Mar-2018	$0.55*	Mar-2023	132	—	—	—	132
Nov-2017	$0.55*	Nov-2022	12	—	—	—	12
May-2015	$11.83	Nov-2024	28	—	—	—	28
Nov-2014	$11.04	Nov-2024	27	—	—	—	27
			199	—	—	—	199

- Definition

Tabular disclosure of an entity's stock, including par or stated value per share, number and dollar amount of share subscriptions, shares authorized, shares issued, shares outstanding, number and dollar amount of shares held in an employee trust, dividend per share, total dividends, share conversion features, par value plus additional paid in capital, the value of treasury stock and other information necessary to a fair presentation, and EPS information. Stock by class includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. Includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity. If more than one issue is outstanding, state the title of each issue and the corresponding dollar amount; dollar amount of any shares subscribed but unissued and the deduction of subscriptions receivable there from; number of shares authorized, issued, and outstanding.

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+ Details

EARNINGS (LOSS) PER SHARE (Tables)

9 Months Ended

Sep. 30, 2022

Earnings Per Share [Abstract]

Schedule of Earnings (Loss) Per Share

The following table illustrates the determination of earnings (loss) per share for each period presented:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
	(in thousands, except per share amounts)
Basic Earnings (Loss) Per Share:
Numerator:
Net income (loss)	$	20,457	$	71,674	$	(12,310)	$	(9,280)

Less: Income attributable to participating securities - basic	(15)		(52)		—		—
Net income (loss) attributable to common stockholders - basic	$	20,442	$	71,622	$	(12,310)	$	(9,280)

Denominator:
Weighted average common shares outstanding - basic	200,464		196,778		199,801		176,547
Net income (loss) per share applicable to common stockholders - basic	$	0.10	$	0.36	$	(0.06)	$	(0.05)

Dilutive Earnings (Loss) Per Share:
Numerator:
Net income (loss)	$	20,457	$	71,674	$	(12,310)	$	(9,280)

Less: Income attributable to participating securities - diluted	(15)		(51)		—		—
Net income (loss) attributable to common stockholders - diluted	$	20,442	$	71,623	$	(12,310)	$	(9,280)

Denominator:
Weighted average shares outstanding	200,464		196,778		199,801		176,547

Dilutive impact from:
Stock options and employee stock purchase plan	20		4,239		—		—
Restricted stock units & performance based stock units	463		—		—		—
Weighted average common shares outstanding - diluted	200,947		201,017		199,801		176,547
Net income (loss) per share applicable to common stockholders - diluted	$	0.10	$	0.36	$	(0.06)	$	(0.05)

Schedule of Potentially Dilutive Securities Excluded from Diluted Loss Calculation


	Three Months Ended September 30,		Nine Months Ended September 30,
	2022	2021	2022	2021
Warrants	55	55	199	199
Stock options	16,182	11,273	16,202	15,511
RSUs and PSUs	4,232	—	4,695	—
Total	20,469	11,328	21,096	15,710

SHARE-BASED COMPENSATION (Tables)

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of Share-Based Compensation Expense


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development	$	863	$	152	$	1,838	$	536
General and administrative	1,305		1,016		4,026		2,849
Total Share Based Compensation	$	2,168	$	1,168	$	5,864	$	3,385

Schedule of Stock Option Activity


	Number of Shares under Option (in thousands)	Weighted-Average Exercise Price	Weighted-Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2021	15,703	$1.93	8.03	$	82
Granted	1,510	$0.72
Exercised	—	—
Canceled or forfeited	(1,011)	2.10
Outstanding at September 30, 2022	16,202	$1.81	7.41	DM
Exercisable at September 30, 2022	10,494	$1.72	6.94	DM

Schedule of Weighted-Average Inputs and Assumptions in Black-Scholes Option


	September 30, 2022	September 30, 2021
Fair market value	$0.72	$3.40
Grant exercise price	$0.72	$3.40
Expected term (in years)	6.0	6.03
Risk-free interest rate	2.1%	0.9%
Expected volatility	71.8%	74.6%
Dividend yield	—%	—%

Schedule of the Status of Restricted Stock Units

The following table sets forth a summary of the Company's RSU and PSU activity for the nine months ended September 30, 2022:


	Restricted Stock Units (in thousands)	Weighted Average Grant Date Fair Value
Unvested at December 31, 2021	3,041	$0.80
Granted RSU	4,160	$0.68
Cancelled RSU	(217)	$0.75
Released RSU	(3,293)	$0.76
Granted PSU	1,004	$0.67
Unvested at September 30, 2022	4,695	$0.68

INCOME TAXES (Tables)

9 Months Ended

Sep. 30, 2022

Income Tax Disclosure [Abstract]

Schedule of Components of Pre-tax Loss

The following table sets forth the components of the Company's loss before income taxes by country (in thousands):


	Nine Months Ended September 30,
	2022		2021
Country:
United States	$	(32,083)	$	(38,864)
Canada	15,898		21,311
Total loss before income taxes	$	(16,185)	$	(17,553)

Schedule of Components of Income Tax Benefit (Provision)

The Company's tax benefit (provision) is comprised of the following components (in thousands):


	Nine Months Ended September 30,
	2022		2021
Current tax benefit (provision)
Federal	$	—	$	8,559
State	—		—
Foreign	3,875		(286)
Total current benefit	$	3,875	$	8,273

Schedule Components of Deferred Tax Liabilities

The Company's deferred tax liability is comprised of the following:


	September 30, 2022		December 31, 2021
Deferred tax liabilities
IPR&D	$	—	$	(3,969)

Total deferred tax liabilities	$	—	$	(3,969)

RESTRUCTURING AND RELATED ACTIVITIES (Tables)

9 Months Ended

Sep. 30, 2022

Restructuring and Related Activities [Abstract]

Schedule of Restructuring Reserve by Type of Cost

The following is a summary of accrued restructuring costs related to the 2022 Restructuring Plan, (in thousands):


	2022 Restructuring Plan
Severance and benefits costs	$	6,944
Contract termination and other associated costs	4,003
Total restructurings costs	10,947
Cash payments	(4,582)
Balance at September 30, 2022	$	6,365

DESCRIPTION OF BUSINESS (Details) - Viventia Bio Inc. shares in Millions, $ in Millions	1 Months Ended
	Sep. 30, 2016 USD ($) shares
Variable Interest Entity [Line Items]
Shares of common stock issued to the selling shareholders (in shares) \| shares	4.0
Percentage of voting interests acquired	19.90%
Period during which quarterly earn-outs are payable after date of net sales	15 years
Period in which acquiree is to use commercially reasonable efforts to achieve marketing authorizations	7 years
Vicinium \| Collaborative Arrangement, Revenue based on Specified Milestone
Variable Interest Entity [Line Items]
Percentage of net sales of quarterly earn-out payments during earn-out periods	2.00%
Vicinium \| Collaborative Arrangement, Revenue based on Specified Milestone \| United States
Variable Interest Entity [Line Items]
One-time milestone payment upon first sale of product	$ 12.5
Vicinium \| Collaborative Arrangement, Revenue based on Specified Milestone \| Europe
Variable Interest Entity [Line Items]
One-time milestone payment upon first sale of product	7.0
Vicinium \| Collaborative Arrangement, Revenue based on Specified Milestone \| Japan
Variable Interest Entity [Line Items]
One-time milestone payment upon first sale of product	$ 3.0

FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Liabilities:
Contingent consideration	$ 0	$ 52,000
Recurring \| Quoted Prices in Active Markets (Level 1)
Assets:
Money market funds (cash equivalents)	11,450	16,382
Marketable securities	0
Liabilities:
Contingent consideration	0	0
Recurring \| Significant Other Observable Inputs (Level 2)
Assets:
Money market funds (cash equivalents)	0	0
Marketable securities	113,763
Liabilities:
Contingent consideration	0	0
Recurring \| Significant Unobservable Inputs (Level 3)
Assets:
Money market funds (cash equivalents)	0	0
Marketable securities	0
Liabilities:
Contingent consideration	0	52,000
Carrying Amount \| Recurring
Assets:
Money market funds (cash equivalents)	11,450	16,382
Marketable securities	113,763
Liabilities:
Contingent consideration	0	52,000
Fair Value \| Recurring
Assets:
Money market funds (cash equivalents)	11,450	16,382
Marketable securities	113,763
Liabilities:
Contingent consideration	$ 0	$ 52,000

FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021
Fair Value, Option, Quantitative Disclosures [Line Items]
Business combination, contingent consideration, liability	$ 0		$ 0		$ 1,800
Contingent consideration liability, measurement input						0.080
License agreement, royalty rate	2.00%		2.00%
Decrease in the fair value of contingent consideration	$ (1,800)	$ (114,000)	$ (52,000)	$ (52,240)
Discount Rate
Fair Value, Option, Quantitative Disclosures [Line Items]
Weighted-average cost of capital						9.30%
Discount Rate \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent consideration liability, measurement input						0.080
Discount Rate \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent consideration liability, measurement input						0.093

FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS - Summary of Changes in Fair Value of Company's Total Contingent Consideration (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Ending balance	$ 0
Significant Unobservable Inputs (Level 3)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	52,000
Change in fair value of contingent consideration	(52,000)
Ending balance	$ 0

RECEIVABLES (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended						9 Months Ended
RECEIVABLES (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Jun. 30, 2021	Sep. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivables			$ 0						$ 0		$ 21,011
License and related revenue			40,000		$ 0				40,000	$ 6,544
Other receivables			$ 14,297						14,297		3,482
Increase in other receivables									10,816	$ 0
Litigation Settlement
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in other receivables									13,400
German VAT recovery
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in other receivables				$ 2,400					$ 200
Qilu Pharmaceutical Co., Ltd.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivables		$ 900				$ 900
Licensing Agreements \| Qilu Pharmaceutical Co., Ltd.
Accounts, Notes, Loans and Financing Receivable [Line Items]
License and related revenue		$ 900				$ 900	$ 2,800	$ 11,200
Roche
Accounts, Notes, Loans and Financing Receivable [Line Items]
Milestone achieved											$ 20,000
Proceeds from milestone achieved	$ 20,000

PREPAID EXPENSES (Details) - USD ($) $ in Millions	3 Months Ended
PREPAID EXPENSES (Details) - USD ($) $ in Millions	Jun. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses		$ 0.5	$ 25.7
Expenses previously classified as prepaid	$ 25.2

INTANGIBLE ASSETS AND GOODWIL - Composition of Intangible Assets (Details) - IPR&D intangible assets: - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Finite-Lived Intangible Assets [Line Items]
Total Intangibles	$ 0		$ 14,700
European Union \| Vicinium
Finite-Lived Intangible Assets [Line Items]
Total Intangibles	$ 0	$ 0	$ 14,700	$ 0

INTANGIBLE ASSETS AND GOODWIL - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Intangibles impairment charge	$ 0		$ 31,700	$ 27,764	$ 31,700
Goodwill	0	$ 0		0		$ 13,064
IPR&D intangible assets:
Finite-Lived Intangible Assets [Line Items]
Total Intangibles	0			0		14,700
Vicinium \| Europe \| IPR&D intangible assets:
Finite-Lived Intangible Assets [Line Items]
Intangibles impairment charge		14,700
Total Intangibles	$ 0	$ 0	$ 0	$ 0	$ 0	$ 14,700

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

INTANGIBLE ASSETS AND GOODWIL - Schedule of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill, Beginning Balance	$ 13,064
Impairment loss	(13,064)
Goodwill, Ending Balance	$ 0

- Definition

+ References + Details

ACCRUED EXPENSES - Components of Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Research and development	$ 1,242	$ 1,841
Payroll-related expenses	2,043	2,967
Restructuring charge related	6,365	1,497
Professional fees	381	597
Legal expenses, including preliminary litigation settlement	23,720	1,344
Other	49	9
Total Accrued Expenses	$ 33,800	$ 8,255

COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	3 Months Ended	9 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Sep. 30, 2022 USD ($) lawsuit	Sep. 30, 2022 USD ($) lawsuit	Nov. 04, 2022 letter	Oct. 21, 2022 letter	Jun. 30, 2022 USD ($)
Gain Contingencies [Line Items]
Number of lawsuits \| lawsuit	3	3
Estimated litigation liability	$ 21,000	$ 21,000			$ 21,600
Payment of litigation fees	600
Subsequent Event
Gain Contingencies [Line Items]
Number of letters from stockholders \| letter			1	2
Carisma
Gain Contingencies [Line Items]
Contingent termination fee, payments to third party	7,600	7,600
Contingent termination fee, proceeds	$ 5,490	5,490
Contingent reimbursement payments to third party		1,750
Contingent reimbursement proceeds		$ 1,750

LEASES (Details) ft² in Thousands, $ in Millions	3 Months Ended			9 Months Ended
LEASES (Details) ft² in Thousands, $ in Millions	Sep. 30, 2022 USD ($) ft²	Sep. 30, 2022 CAD ($) ft²	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease cost, including related operating cost	$ 81,000		$ 79,000	$ 245,000	$ 245,000
Right-of-use asset	$ 0			$ 0		$ 123,300
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets			Other assets		Other assets
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities			Other current liabilities		Other current liabilities
Short term lease liability	$ 0			$ 0		$ 123,300
Canada
Lessee, Lease, Description [Line Items]
Office space (in square feet) \| ft²	31	31
Operating lease, termination expense	$ 900,000	$ 1.2
Massachusetts
Lessee, Lease, Description [Line Items]
Monthly rent				2,500
Pennsylvania
Lessee, Lease, Description [Line Items]
Monthly rent				$ 17,200

STOCKHOLDERS' EQUITY - Equity Financing (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		2 Months Ended	3 Months Ended	9 Months Ended
	Nov. 29, 2021	Jul. 31, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2022	Dec. 31, 2021	Nov. 29, 2019
Class of Stock [Line Items]
Common stock, par value (in dollars per share)					$ 0.001	$ 0.001
ATM Facility
Class of Stock [Line Items]
Common stock, par value (in dollars per share)							$ 0.001
Aggregate sales price		$ 200.0
Shares reserved for future issuance amount					$ 97.8
Commission fixed rate	3.00%
Proceeds from sale of stock			$ 38.2	$ 175.0
Sale of stock, number of units issued (in shares)			9.8	56.9
Weighted-average stock price per share (in dollars per share)			$ 4.01	$ 3.17
Issuance of common stock, issuance cost			$ 1.2	$ 5.4

STOCKHOLDERS' EQUITY - Preferred Stock (Details) - $ / shares	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Equity [Abstract]
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares issued (in shares)	0	0	0
Preferred stock, shares outstanding (in shares)	0	0	0

STOCKHOLDERS' EQUITY - Common Stock (Details)	9 Months Ended
STOCKHOLDERS' EQUITY - Common Stock (Details)	Sep. 30, 2022 vote shares	Dec. 31, 2021 shares	May 03, 2021 shares	May 02, 2021 shares
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	400,000,000	400,000,000	400,000,000	200,000,000
Common stock, shares issued (in shares)	202,757,012	199,463,645
Common stock, shares outstanding (in shares)	202,757,012	199,463,645
Common Stock
Class of Stock [Line Items]
Number of votes \| vote	1

STOCKHOLDERS' EQUITY - Summary of Common Stock Issued and Reserved for Issuance (Details) - shares	Sep. 30, 2022	Dec. 31, 2021
Class of Warrant or Right [Line Items]
Shares of common stock issued (in shares)	202,757,012	199,463,645
Shares of common stock reserved for issuance for:
Total shares of common stock issued and reserved for issuance (in shares)	229,878,000	229,640,000
Warrants
Shares of common stock reserved for issuance for:
Shares of common stock reserved for issuance (in shares)	199,000	199,000
Stock options
Shares of common stock reserved for issuance for:
Shares of common stock reserved for issuance (in shares)	16,202,000	15,703,000
Restricted stock units
Shares of common stock reserved for issuance for:
Shares of common stock reserved for issuance (in shares)	4,695,000	3,041,000
Shares available for grant under 2014 Stock Incentive Plan
Shares of common stock reserved for issuance for:
Shares of common stock reserved for issuance (in shares)	3,725,000	8,933,000
Shares available for sale under 2014 Employee Stock Purchase Plan
Shares of common stock reserved for issuance for:
Shares of common stock reserved for issuance (in shares)	2,300,000	2,300,000

STOCKHOLDERS' EQUITY - Warrants (Details) shares in Thousands	9 Months Ended
	Sep. 30, 2022 $ / shares shares
Warrant Or Right Outstanding [Roll Forward]
Warrants outstanding, beginning balance (in shares)	199
Warrants Issued (in shares)	0
Warrants Exercised (in shares)	0
Warrants Cancelled (in shares)	0
Warrants outstanding, ending balance (in shares)	199
Warrants, Expiring March 2023
Class of Warrant or Right [Line Items]
Exercise price per warrant (in dollars per share) \| $ / shares	$ 0.55
Warrant Or Right Outstanding [Roll Forward]
Warrants outstanding, beginning balance (in shares)	132
Warrants Issued (in shares)	0
Warrants Exercised (in shares)	0
Warrants Cancelled (in shares)	0
Warrants outstanding, ending balance (in shares)	132
Warrants, Expiring November 2022
Class of Warrant or Right [Line Items]
Exercise price per warrant (in dollars per share) \| $ / shares	$ 0.55
Warrant Or Right Outstanding [Roll Forward]
Warrants outstanding, beginning balance (in shares)	12
Warrants Issued (in shares)	0
Warrants Exercised (in shares)	0
Warrants Cancelled (in shares)	0
Warrants outstanding, ending balance (in shares)	12
Warrants, Expiring November 2024, Issued May 2015
Class of Warrant or Right [Line Items]
Exercise price per warrant (in dollars per share) \| $ / shares	$ 11.83
Warrant Or Right Outstanding [Roll Forward]
Warrants outstanding, beginning balance (in shares)	28
Warrants Issued (in shares)	0
Warrants Exercised (in shares)	0
Warrants Cancelled (in shares)	0
Warrants outstanding, ending balance (in shares)	28
Warrants, Expiring November 2024, Issued November 2014
Class of Warrant or Right [Line Items]
Exercise price per warrant (in dollars per share) \| $ / shares	$ 11.04
Warrant Or Right Outstanding [Roll Forward]
Warrants outstanding, beginning balance (in shares)	27
Warrants Issued (in shares)	0
Warrants Exercised (in shares)	0
Warrants Cancelled (in shares)	0
Warrants outstanding, ending balance (in shares)	27

EARNINGS (LOSS) PER SHARE - Schedule of EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net income (loss)	$ 20,457	$ (31,960)	$ (807)	$ 71,674	$ (25,442)	$ (55,512)	$ (12,310)	$ (9,280)
Less: Income attributable to participating securities - basic	(15)			(52)			0	0
Net income (loss) attributable to common stockholders - basic	$ 20,442			$ 71,622			$ (12,310)	$ (9,280)
Denominator:
Weighted-average common shares outstanding - basic (in shares)	200,464			196,778			199,801	176,547
Net loss per common share - basic (in dollars per share)	$ 0.10			$ 0.36			$ (0.06)	$ (0.05)
Dilutive Earnings (Loss) Per Share:
Less: Income attributable to participating securities - diluted	$ (15)			$ (51)			$ 0	$ 0
Net income (loss) attributable to common stockholders - diluted	$ 20,442			$ 71,623			$ (12,310)	$ (9,280)
Denominator:
Weighted-average common shares outstanding - diluted (in shares)	200,947			201,017			199,801	176,547
Net loss per common share - diluted (in dollars per share)	$ 0.10			$ 0.36			$ (0.06)	$ (0.05)
Stock options
Denominator:
Incremental common shares attributable to dilutive effect of share-based payment arrangements (in shares)	20			4,239			0	0
Restricted Stock Units & Performance Based Stock Units
Denominator:
Incremental common shares attributable to dilutive effect of share-based payment arrangements (in shares)	463			0			0	0

EARNINGS (LOSS) PER SHARE - Schedule of Antidilutive Securities (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	20,469	11,328	21,096	15,710
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	55	55	199	199
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	16,182	11,273	16,202	15,511
RSU
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	4,232	0	4,695	0
PSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	4,232	0	4,695	0

SHARE-BASED COMPENSATION - Share-Based Compensation Expense (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]
Total Share Based Compensation	$ 2,168	$ 1,168	$ 5,864	$ 3,385
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share Based Compensation	863	152	1,838	536
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share Based Compensation	$ 1,305	$ 1,016	$ 4,026	$ 2,849

SHARE-BASED COMPENSATION - Narrative (Details) - USD ($)	1 Months Ended		3 Months Ended		9 Months Ended
	May 31, 2021	Jun. 30, 2019	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Oct. 01, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)			16,202,000		16,202,000		15,703,000
Share-based compensation expense			$ 2,168,000	$ 1,168,000	$ 5,864,000	$ 3,385,000
Unrecognized compensation cost, non-vested stock options			$ 6,400,000		$ 6,400,000
Weighted average period unvested stock to be recognized					2 years 1 month 2 days
Weighted-average grant-date fair value of stock options granted (in dollars per share)					$ 0.46	$ 2.20
Exercise of stock options (in shares)					0
Share-based Payment Arrangement, Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)			3,100,000		3,100,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)			16,202,000		16,202,000		15,703,000
Share-based compensation expense			$ 1,000,000	1,200,000	$ 3,500,000	$ 3,400,000
Stock options \| 2014 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance (in shares)	12,000,000	7,900,000
Shares reserved for future issuance (in shares)			3,700,000		3,700,000
Award vesting period					4 years
Expected term					10 years
Options outstanding (in shares)			13,000,000		13,000,000
Stock options \| 2014 Stock Incentive Plan \| Vesting on the First Anniversary of Date of Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of original number of shares subject to the option vesting					25.00%
Stock options \| 2014 Stock Incentive Plan \| Vesting at End of Each Successive Three-Month Period Thereafter
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of original number of shares subject to the option vesting					6.25%
Stock options \| Stock Incentive Plan 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term					10 years
Vested stock options outstanding (in shares)					100,000
RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)			4,695,000		4,695,000		3,041,000
Unrecognized compensation expense			$ 1,800,000		$ 1,800,000
Share-based compensation expense			1,200,000		$ 2,400,000	$ 0
Unvested grant restricted stock units (in shares)					4,160,000	0
RSU \| Retention Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares received per award (in shares)								1
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			1,800,000		$ 1,800,000
Share-based compensation expense			1,200,000	$ 0	$ 2,400,000
Unvested grant restricted stock units (in shares)					1,004,000	0
PSUs \| Retention Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares received per award (in shares)								1
Percent of base salary								50.00%
Unrecognized compensation expense			$ 43,000		$ 43,000		$ 87,000	$ 400,000
Achievement deemed probable, percent			20.00%		20.00%
Share-based compensation expense			$ 11,000		$ 44,000

SHARE-BASED COMPENSATION - Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Number of Shares under Option (in thousands)
Outstanding at beginning of period (in shares)	15,703,000	15,703,000
Granted (in shares)		1,510,000
Exercised (in shares)		0
Canceled or forfeited (in shares)		(1,011,000)
Outstanding at end of period (in shares)		16,202,000
Exercisable at end of period (in shares)		10,494,000
Weighted-Average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 1.93	$ 1.93
Granted (in dollars per share)		0.72
Exercised (in dollars per share)		0
Cancelled or forfeited (in dollars per share)		2.10
Outstanding at end of period (in dollars per share)		1.81
Exercisable at end of period (in dollars per share)		$ 1.72
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-average Remaining Contractual Life (in years), Outstanding	8 years 10 days	7 years 4 months 28 days
Weighted-average Remaining Contractual Life (in years), Exercisable		6 years 11 months 8 days
Aggregate Intrinsic Value, Outstanding			$ 82

SHARE-BASED COMPENSATION - Weighted-Average Inputs and Assumptions (Details) - Stock options - $ / shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair market value (in dollars per share)	$ 0.72	$ 3.40
Grant exercise price (in dollars per share)	$ 0.72	$ 3.40
Expected term (in years)	6 years	6 years 10 days
Risk-free interest rate	2.10%	0.90%
Expected volatility	71.80%	74.60%
Dividend yield	0.00%	0.00%

SHARE-BASED COMPENSATION - Summary of Status and Changes of Unvested Restricted Stock (Details) - $ / shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Number of Shares
Unvested, beginning balance (in shares)	3,041,000
Unvested, ending balance (in shares)	4,695,000
Weighted-Average Grant Date Fair Value
Unvested beginning balance (in dollars per share)	$ 0.80
Unvested ending balance (in dollars per share)	$ 0.68
RSU
Number of Shares
Granted (in shares)	4,160,000	0
Cancelled RSU (in shares)	(217,000)
Released RSU (in shares)	(3,293,000)
Weighted-Average Grant Date Fair Value
Granted (in dollars per share)	$ 0.68
Cancelled RSU (in dollars per share)	0.75
Released RSU (in dollars per share)	$ 0.76
PSUs
Number of Shares
Granted (in shares)	1,004,000	0
Weighted-Average Grant Date Fair Value
Granted (in dollars per share)	$ 0.67

EMPLOYEE BENEFIT PLANS (Details) - USD ($) shares in Millions	1 Months Ended	9 Months Ended
	May 31, 2021	Sep. 30, 2022	Feb. 28, 2014
United States
Defined Benefit Plan Disclosure [Line Items]
Defined contribution retirement plan, maximum employee contribution deferred		100.00%
Discretionary match per participating employee, maximum		$ 4,000
Canada
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of employees' eligible compensation		4.00%
2014 Employee Stock Purchase Plan
Defined Benefit Plan Disclosure [Line Items]
Shares of common stock reserved for issuance (in shares)			0.2
Number of additional shares authorized (in shares)	2.3
Common stock purchase price, discount rate		15.00%
Common stock available for sale (in shares)		2.3

INCOME TAXES - Components of Pre-tax Income (Loss) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Income Taxes [Line Items]
Pre-tax income (loss) U.S.	$ (32,083)	$ (38,864)
Pre-tax income (loss) Canada	15,898	21,311
Total loss before income taxes	$ (16,185)	$ (17,553)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=126941158&loc=d3e41242-110953

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-URI https://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8924-108599

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ Details

INCOME TAXES - Components of Income Tax Provisions (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Current tax benefit (provision)
Federal	$ 0	$ 8,559
State	0	0
Foreign	3,875	(286)
Total current benefit	$ 3,875	$ 8,273

INCOME TAXES - Components of Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Deferred Tax Liabilities, Gross [Abstract]
IPR&D	$ 0	$ (3,969)
Total deferred tax liabilities	$ 0	$ (3,969)

INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Income Taxes [Line Items]
Benefit from income taxes	$ 0		$ 8,561	$ 3,875	$ 8,273
Increase (decrease) in deferred tax liability	(4,000)		(8,600)	(4,000)	(8,600)
Income Taxes Paid				100
IPR&D intangible assets:
Income Taxes [Line Items]
Intangible assets	0			0		$ 14,700
Vicinium \| Europe \| IPR&D intangible assets:
Income Taxes [Line Items]
Intangible assets	$ 0	$ 0	0	$ 0	$ 0	$ 14,700
Impairment of intangible assets		$ 14,700	$ 31,700

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

LICENSE AGREEMENTS (Details) € in Thousands				1 Months Ended		3 Months Ended								9 Months Ended
LICENSE AGREEMENTS (Details) € in Thousands	Aug. 05, 2021 USD ($)	Nov. 30, 2020 USD ($)	Jul. 30, 2020 USD ($)	Jul. 31, 2022 USD ($)	Jun. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2021 EUR (€)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 EUR (€)	Sep. 30, 2020 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2022 EUR (€)	Sep. 30, 2021 USD ($)
Organization And Basis Of Presentation [Line Items]
License and related revenue						$ 40,000,000	$ 0							$ 40,000,000		$ 6,544,000
Variable consideration						30,000,000								$ 30,000,000
Transaction price											$ 11,200,000
Qilu Pharmaceutical Co., Ltd. \| Licensing Agreements
Organization And Basis Of Presentation [Line Items]
Potential milestone payments									$ 23,000,000
License and related revenue					$ 900,000			$ 900,000	2,800,000				$ 11,200,000
Upfront payment			$ 12,000,000						12,000,000
Total milestone payments			$ 23,000,000
Royalty payment, percentage			12.00%
Business combination, milestone payments									3,000,000
University of Zurich
Organization And Basis Of Presentation [Line Items]
Royalty payment obligation, percent														4.00%	4.00%
Third party maximum ownership, percent														10.00%	10.00%
Third party minimum ownership, percent														2.00%	2.00%
Expenses related to achievement of development milestone							$ 500,000				300,000
University of Zurich \| Collaborative Arrangement, Revenue Based on Clinical Development Milestone
Organization And Basis Of Presentation [Line Items]
License agreement, amount payable upon achievement of specified milestone														$ 500,000
Micromet AG
Organization And Basis Of Presentation [Line Items]
Royalty payment obligation, percent														3.50%	3.50%
Expenses related to achievement of development milestone									$ 600,000	€ 500	$ 900,000	€ 700
Potential milestone payments														$ 2,400,000	€ 2,400
License agreement, royalty payment, reduction, conditions not met														1.50%	1.50%
License maintenance fees														$ 48,987	€ 50
XOMA Ireland Limited
Organization And Basis Of Presentation [Line Items]
License agreement, amount payable upon achievement of specified milestone														$ 250,000
Royalty payment obligation, percent														2.50%	2.50%
Third party maximum ownership, percent														50.00%	50.00%
Third party minimum ownership, percent														1.75%	1.75%
Roche
Organization And Basis Of Presentation [Line Items]
Other receivable, asset purchase agreement						$ 30,000,000								$ 30,000,000
Payments to company upon execution of the Roche Asset Purchase Agreement				$ 40,000,000
Roche \| EBI-031
Organization And Basis Of Presentation [Line Items]
Other receivable, asset purchase agreement				$ 70,000,000
Qilu Pharmaceutical Co., Ltd.
Organization And Basis Of Presentation [Line Items]
Royalty period			12 years
MENA License Agreement \| Licensing Agreements
Organization And Basis Of Presentation [Line Items]
Upfront payment		$ 3,000,000
Eczacibasi Pharmaceuticals Marketing Agreement
Organization And Basis Of Presentation [Line Items]
Potential milestone payments	$ 2,000,000
Transaction price	$ 1,500,000
Eczacibasi Pharmaceuticals Marketing Agreement \| TURKEY
Organization And Basis Of Presentation [Line Items]
Royalty revenue, percentage	0.30

RESTRUCTURING AND RELATED ACTIVITIES - Schedule of Restructuring Reserve by Type of Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring charge	$ 10,947	$ 5,522	$ 10,947	$ 5,522
Cash payments			(4,582)
Restructuring Reserve	$ 6,365		6,365
Severance and benefits costs
Restructuring Cost and Reserve [Line Items]
Restructuring charge			6,944
Contract termination and other associated costs
Restructuring Cost and Reserve [Line Items]
Restructuring charge			$ 4,003

SUBSEQUENT EVENTS (Details) - letter	Nov. 04, 2022	Oct. 21, 2022
Subsequent Event
Subsequent Event [Line Items]
Number of letters from stockholders	1	2