Immunomedics (IMMU) 10-Q 7 Aug 19 2019 Q2 Quarterly report Financial data

COVER PAGE

COVER PAGE - shares	6 Months Ended
	Jun. 30, 2019	Aug. 02, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
Document Transition Report	false
Entity File Number	0-12104
Entity Registrant Name	Immunomedics, Inc.
Entity Central Index Key	0000722830
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	61-1009366
Entity Address, Address Line One	300 The American Road
Entity Address, City or Town	Morris Plains
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07950
City Area Code	973
Local Phone Number	605-8200
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	IMMU
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		191,978,434

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current Assets:
Cash and cash equivalents	$ 427,909	$ 492,860
Marketable securities	4,741	4,941
Prepaid expenses	8,296	5,354
Other current assets	1,313	1,348
Total current assets	442,259	504,503
Property and equipment, net of accumulated depreciation and amortization of $6,260 and $4,316 at June 30, 2019 and December 31, 2018, respectively	35,177	23,469
Other long-term assets	249	68
Total Assets	477,685	528,040
Current Liabilities:
Accounts payable and accrued expenses	38,967	31,722
Liability related to sale of future royalties - current	5,314	0
Lease liability - current	271
Total current liabilities	44,552	31,722
Convertible senior notes, net	7,081	7,055
Liability related to sale of future royalties - non-current	236,354	221,295
Deferred revenues	65,000	0
Other long-term liabilities	10,138	2,119
Total Liabilities	363,125	262,191
Commitments and Contingencies
Stockholders' Equity:
Convertible preferred stock, $0.01 par value; authorized 10,000,000 shares; no shares issued and outstanding at June 30, 2019 and December 31, 2018	0	0
Common stock, $0.01 par value; authorized 250,000,000 shares; issued 191,972,321 shares and outstanding 191,852,700 shares at June 30, 2019; issued 190,445,795 shares and outstanding 190,411,070 shares at December 31, 2018	1,920	1,905
Capital contributed in excess of par	1,232,575	1,219,237
Treasury stock, at cost: 119,621 shares at June 30, 2019 and 34,725 shares at December 31, 2018	(2,095)	(824)
Accumulated deficit	(1,116,506)	(953,216)
Accumulated other comprehensive loss	(365)	(351)
Total Immunomedics, Inc. stockholders' equity	115,529	266,751
Noncontrolling interest in subsidiary	(969)	(902)
Total stockholders' equity	114,560	265,849
Total Liabilities and Stockholders' Equity	$ 477,685	$ 528,040

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property and equipment, accumulated depreciation	$ 6,260	$ 4,316
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	250,000,000,000	250,000,000,000
Common stock, shares issued (in shares)	191,972,321	190,445,795
Common stock, shares outstanding (in shares)	191,852,700	190,411,070
Treasury stock, shares (in shares)	119,621	34,725
Convertible Preferred Stock
Preferred stock, par value (in usd per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Total revenues	$ 0	$ 386	$ 0	$ 868
Costs and Expenses:
Costs of goods sold	0	0	0	47
Research and development	52,923	27,603	111,095	56,446
Sales and marketing	6,346	3,039	14,227	5,405
General and administrative	7,899	22,139	21,494	28,993
Total costs and expenses	67,168	52,781	146,816	90,891
Operating loss	(67,168)	(52,395)	(146,816)	(90,023)
Changes in fair market value of warrant liabilities	0	(58,861)	0	(49,026)
Interest expense	(10,625)	(9,434)	(20,584)	(20,334)
Interest and other income	1,840	3,565	4,043	4,695
Insurance reimbursement	0	342	0	2,272
Foreign currency transaction loss, net	0	(101)	0	(26)
Loss before income tax	(75,953)	(116,884)	(163,357)	(152,442)
Income tax expense	0	(156)	0	(156)
Net loss	(75,953)	(117,040)	(163,357)	(152,598)
Net loss attributable to noncontrolling interest	0	(11)	(67)	(23)
Net loss attributable to Immunomedics, Inc. stockholders	$ (75,953)	$ (117,029)	$ (163,290)	$ (152,575)
Loss per common share attributable to Immunomedics, Inc. stockholders (basic and diluted) (in usd per share)	$ (0.40)	$ (0.68)	$ (0.85)	$ (0.91)
Weighted average shares used to calculated loss per common share (basic and diluted) (in shares)	191,745	171,124	191,401	168,583
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	$ 195	$ 50	$ 186	$ (16)
Unrealized gain (loss) on securities available for sale	0	54	(200)	64
Other comprehensive loss, net of tax:	195	104	(14)	48
Comprehensive loss	(75,758)	(116,936)	(163,371)	(152,550)
Comprehensive loss attributable to noncontrolling interest	0	(11)	(67)	(23)
Comprehensive loss attributable to Immunomedics, Inc. stockholders	(75,758)	(116,925)	(163,304)	(152,527)
Product sales
Total revenues	0	0	0	450
License fee and other revenues
Total revenues	0	250	0	265
Research and development
Total revenues	$ 0	$ 136	$ 0	$ 153

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Issuance of common stock to RPI Finance Trust	Common Stock	Common StockIssuance of common stock to RPI Finance Trust	Capital Contributed in Excess of Par	Capital Contributed in Excess of ParIssuance of common stock to RPI Finance Trust	Treasury Stock	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest	Convertible Preferred Stock
Beginning balance (in shares) at Dec. 31, 2017			161,303								0
Beginning Balance at Dec. 31, 2017	$ 16,450		$ 1,613		$ 659,467		$ (458)	$ (642,973)	$ (401)	$ (798)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of warrant liability to equity, net	137,976				137,976
Exercise of stock options (in shares)			403
Exercise of stock options, net	1,596		$ 4		1,592
Stock-based compensation (in shares)			284
Stock-based compensation	2,685		$ 3		2,682
Exercise of common stock warrants (in shares)			7,400
Exercise of common stock warrants	27,750		$ 74		27,676
Issuance of common stock (in shares)			13,225	4,373
Issuance of common stock	299,467	$ 67,784	$ 132	$ 44	299,335	$ 67,740
Conversion of RSU's for tax withholding payments (in shares)			(187)
Conversion of RSU's for tax withholding payments	(1,472)		$ (2)		(1,470)
Other comprehensive gain (loss)	48								48
Net loss	(152,598)							(152,575)		(23)
Ending balance (in shares) at Jun. 30, 2018			186,801								0
Ending Balance at Jun. 30, 2018	399,686		$ 1,868		1,194,998		(458)	(795,548)	(353)	(821)	$ 0
Beginning balance (in shares) at Mar. 31, 2018			167,256								0
Beginning Balance at Mar. 31, 2018	71,820		$ 1,672		750,392		(458)	(678,519)	(457)	(810)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of warrant liability to equity, net	120,219				120,219
Exercise of stock options (in shares)			320
Exercise of stock options, net	1,262		$ 4		1,258
Stock-based compensation	1,354				1,354
Exercise of common stock warrants (in shares)			6,000
Exercise of common stock warrants	22,500		$ 60		22,440
Issuance of common stock (in shares)			13,225
Issuance of common stock	299,467		$ 132		299,335
Other comprehensive gain (loss)	104								104
Net loss	(117,040)							(117,029)		(11)
Ending balance (in shares) at Jun. 30, 2018			186,801								0
Ending Balance at Jun. 30, 2018	399,686		$ 1,868		1,194,998		(458)	(795,548)	(353)	(821)	$ 0
Beginning balance (in shares) at Dec. 31, 2018			190,446								0
Beginning Balance at Dec. 31, 2018	265,849		$ 1,905		1,219,237		(824)	(953,216)	(351)	(902)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			1,140
Exercise of stock options, net	2,106		$ 11		3,366		(1,271)
Stock-based compensation (in shares)			15
Stock-based compensation	4,147		$ 0		4,147
Issuance of common stock (in shares)			371
Issuance of common stock	5,829		$ 4		5,825
Other comprehensive gain (loss)	(14)								(14)
Net loss	(163,357)							(163,290)		(67)
Ending balance (in shares) at Jun. 30, 2019			191,972								0
Ending Balance at Jun. 30, 2019	114,560		$ 1,920		1,232,575		(2,095)	(1,116,506)	(365)	(969)	$ 0
Beginning balance (in shares) at Mar. 31, 2019			191,509								0
Beginning Balance at Mar. 31, 2019	181,804		$ 1,915		1,224,066		(2,095)	(1,040,553)	(560)	(969)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			77
Exercise of stock options, net	281		$ 1		280		0
Stock-based compensation (in shares)			15
Stock-based compensation	2,404		$ 0		2,404
Issuance of common stock (in shares)			371
Issuance of common stock	5,829		$ 4		5,825
Other comprehensive gain (loss)	195								195
Net loss	(75,953)							(75,953)		0
Ending balance (in shares) at Jun. 30, 2019			191,972								0
Ending Balance at Jun. 30, 2019	$ 114,560		$ 1,920		$ 1,232,575		$ (2,095)	$ (1,116,506)	$ (365)	$ (969)	$ 0

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net loss	$ (163,357)	$ (152,598)
Adjustments to reconcile net loss to net cash used in operating activities:
Changes in fair value of warrant liabilities	0	49,026
Depreciation and amortization	1,839	670
Interest on non-recourse debt	20,373	19,790
Amortization of deferred revenue	0	13
Amortization of bond premiums	0	36
Amortization of debt issuance costs	25	73
Amortization of deferred rent	0	218
Right-of-use asset amortization	130	0
Decrease in allowance for doubtful accounts	0	(13)
Non-cash expense related to stock-based compensation	4,147	2,682
Changes in deferred revenue	65,000	0
Changes in other operating assets and liabilities	4,670	10,456
Net cash used in operating activities	(67,173)	(69,647)
Cash flows from investing activities
Purchases of marketable securities	0	(135)
Proceeds from sales/maturities of marketable securities	0	52,150
Purchases of property and equipment	(5,699)	(7,985)
Net cash (used in) provided by investing activities	(5,699)	44,030
Cash flows from financing activities:
Exercise of stock options, net	2,106	1,596
Exercise of warrants	0	27,750
Proceeds from the issuance of common stock in at-the-market offering	5,829	0
Proceeds from the issuance of non-recourse debt	0	182,216
Debt conversion fees	0	(3)
Tax withholding payments for stock-based compensation	0	(1,472)
Net cash provided by financing activities	7,935	577,338
Effect of changes in exchange rates on cash, cash equivalents and restricted cash	(14)	(99)
Net (decrease) increase in cash, cash equivalents and restricted cash	(64,951)	551,622
Cash, cash equivalents and restricted cash beginning of period	494,173	60,960
Cash, cash equivalents and restricted cash end of period	429,222	612,582
Supplemental disclosure of cash flow information:
Interest paid	169	475
Schedule for non-cash investing and financing activities:
Non-cash component of warrant exercise	0	137,979
Accrued capital expenditures	404	2,173
Shares received in cashless exercise	1,272	0
Total cash, cash equivalents and restricted cash	494,173	60,960
Private placement
Cash flows from financing activities:
Proceeds from private offering of common stock	0	67,784
Public offering
Cash flows from financing activities:
Proceeds from private offering of common stock	$ 0	$ 299,467

Business Overview, Basis of Pre

Business Overview, Basis of Presentation and Recent Accounting Pronouncements	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Overview, Basis of Presentation and Recent Accounting Pronouncements	Reference is made to the Transition Report on Form 10-K, of Immunomedics, Inc., a Delaware corporation (“Immunomedics,” the “Company,” “we,” “our” or “us”), for the six months ended December 31, 2018 , which contains our audited consolidated financial statements and the notes thereto. Business Overview, Basis of Presentation and Recent Accounting Pronouncements Business Overview Immunomedics, Inc., a Delaware corporation, together with its subsidiaries (collectively "we," "our," "us," "Immunomedics", or the "Company"), is a clinical-stage biopharmaceutical company that develops monoclonal antibody-based products for the targeted treatment of cancer. Immunomedics manages its operations as one line of business of researching, developing, manufacturing and marketing biopharmaceutical products, particularly antibody-based products for patients with difficult to treat solid tumor and blood cancers. The Company currently reports as a single industry segment with substantially all business conducted in the United States. Immunomedics conducts its research activities in the United States and runs its development studies in the United States and selected European countries. Our corporate objective is to become a fully-integrated biopharmaceutical company and a leader in the field of antibody-drug conjugates (“ADCs”). To that end, our immediate priority is to commercialize our most advanced ADC product candidate, sacituzumab govitecan ("IMMU-132"), beginning in the United States, with metastatic triple-negative breast cancer (“mTNBC”) as the first indication. On May 21, 2018, we submitted a Biologics License Application (“BLA”) to the United States Food and Drug Administration ("FDA") for sacituzumab govitecan for the treatment of patients with mTNBC who have received at least two prior therapies for metastatic disease. On July 18, 2018, we received notification from the FDA that the BLA was accepted for filing and the original application was granted Priority Review with a Prescription Drug User Fee Act ("PDUFA") target action date of January 18, 2019. On January 17, 2019, we received a Complete Response Letter ("CRL") from the FDA for the BLA. On February 4, 2019, we received a written communication from the FDA enclosing the Establishment Inspection Report (“EIR”) from the chemistry, manufacturing and controls ("CMC") BLA pre-approval inspection conducted by the FDA at the Company’s Morris Plains, New Jersey antibody manufacturing facility for our ADC product candidate sacituzumab govitecan, which took place from August 6, 2018 through August 14, 2018. The FDA also notified the Company that the FDA will be conducting a re-inspection of the Company’s Morris Plains, New Jersey antibody manufacturing facility as part of the BLA resubmission process. The Company is finalizing its plans with respect to the matters raised in the CRL received from FDA on January 17, 2019 and the EIR. The Company met with the FDA on May 2, 2019 to review the FDA's findings and discussed the Company's BLA resubmission. Basis of Presentation The accompanying unaudited condensed consolidated financial statements of Immunomedics, which incorporates our foreign subsidiary, Immunomedics GmbH in Rödermark, Germany, have been prepared in accordance with United States generally accepted accounting principles (“GAAP”), for interim financial information and the instructions to the Quarterly Report on Form 10‑Q and Regulation S‑X. Accordingly, the statements do not include all of the information and footnotes required by GAAP for complete annual financial statements. With respect to the financial information for the interim periods included in this Quarterly Report on Form 10-Q, which is unaudited, management believes that all adjustments (consisting of normal recurring accruals), considered necessary for a fair presentation of the results for such interim periods have been included. Operating results for the three and six-month periods ended June 30, 2019 , are not necessarily indicative of the results that may be expected for the full calendar year ending December 31, 2019, or any other period. The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect reported amounts and disclosures. Actual results could differ from those estimates. Our significant accounting policies are described in Note 2 of Notes to Consolidated Financial Statements included in our 2018 Transition Report on Form 10-K. Such significant accounting policies are applicable for periods prior to the adoption of the following new accounting standards. Recent Accounting Pronouncements Accounting Pronouncements adopted during the year: The Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2019-01, “Leases Topic 842,” requiring entities to recognize assets and liabilities on the balance sheet for all leases, with certain exceptions. Topic 842 allows for a modified retrospective application and is effective as of the first quarter of 2019. Entities are allowed to apply the new guidance using a modified retrospective approach at the beginning of the year in which new lease standard is adopted, rather than to the earliest comparative period presented in their financial statements. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. We elected the modified retrospective approach under the new guidance and elected the available practical expedients on adoption. Upon adoption, we recognized additional operating lease liabilities of $8.4 million with a corresponding right-of-use assets of $8.4 million based on the present value of the remaining lease payments under existing operating leases. As of December 31, 2018, we had $2.1 million in deferred charges related to our real estate leases that were recorded against the lease liability asset as part of the transition, resulting in $10.5 million included in other long-term liabilities on our condensed consolidated balance sheet. In addition, the new guidance resulted in additional lease-related disclosures in the footnotes to our condensed consolidated financial statements. Our leasing portfolio is comprised entirely of operating leases, and we do not recognize right-of-use assets or related lease liabilities with a lease term of twelve months or less on our condensed consolidated balance sheet. Adoption of Topic 842 has required changes to our business processes and controls to comply with the provisions of the standard. Refer to Note 11 "Commitments and Contingencies" for additional information. In June 2018, the FASB issued ASU 2018-07, "Compensation-Stock Compensation," to improve the usefulness of information provided to users of financial statements while reducing cost and complexity in financial reporting and provide guidance aligning the measurement and classification for share-based payments to nonemployees with the guidance for share-based payments to employees. Under the guidance, the measurement of equity-classified nonemployee awards will be fixed at the grant date. This standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. Early adoption is permitted, but no earlier than an entity's adoption date of ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).” We adopted ASU 2018-07 during the first quarter of 2019 and the adoption did not have a material impact to our condensed consolidated financial statements. Accounting Pronouncements yet to be adopted: In November 2018, the FASB issued ASU 2018-18, "Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606," to clarify when ASC 606 should be used for collaborative arrangements when the counterparty is a customer. The guidance precludes an entity from presenting consideration from a transaction in a collaborative arrangement as revenue from contracts with customers if the counterparty is not a customer for that transaction. The guidance is effective for public business entities in fiscal years beginning after December 15, 2019, and interim periods therein. Early adoption is permitted to entities that have adopted ASC 606. We are currently assessing the impact of ASU 2018-18. In August 2018, the FASB issued ASU 2018-13, "Fair Value measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement," to no longer require public companies to disclose transfers between Level 1 and Level 2 of the fair value hierarchy, and to require disclosure about the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. The guidance is effective for fiscal years beginning after December 15, 2019, and for interim periods within those fiscal years. Entities are permitted to early adopt either the entire standard or only the provisions that eliminate or modify the requirements. We are currently assessing the impact of ASU 2018-13.

Revenue Recognition

Revenue Recognition	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition Pursuant to Topic 606, we recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, Topic 606 includes provisions within a five step model that includes i) identifying the contract with a customer, ii) identifying the performance obligations in the contract, iii) determining the transaction price, iv) allocating the transaction price to the performance obligations, and v) recognizing revenue when, or as, an entity satisfies a performance obligation. At contract inception, we assess the goods or services promised within each contract and assess whether each promised good or service is distinct and determine those that are performance obligations. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when the performance obligation is satisfied. Everest Medicines II Limited: On April 29, 2019, the Company entered into a license agreement (the “License Agreement”) with Everest Medicines II Limited, a China limited company (“Everest”). Pursuant to the License Agreement, the Company granted Everest an exclusive license to develop and commercialize sacituzumab govitecan in the People’s Republic of China, Taiwan, Hong Kong, Macao, Indonesia, Philippines, Vietnam, Thailand, South Korea, Malaysia, Singapore and Mongolia (the "Territory"). In consideration for entering into the License Agreement, Everest made a one-time, non-refundable upfront payment to the Company in the aggregate amount of $65.0 million which is recorded as deferred revenue. The License Agreement contains a development milestone payment of $60.0 million based upon the Company’s achievement of FDA approval for sacituzumab govitecan in mTNBC. The License Agreement also contains additional development milestone payments in a total amount of up to $180.0 million based upon the achievement of certain other development milestones. In addition, the License Agreement contains sales milestone payments in a total amount of up to $530.0 million based upon the achievement of certain sales milestones. Everest will make royalty payments to the Company based upon percentages of net sales of sacituzumab govitecan, ranging from 14% to 20% . The Company assessed the arrangement in accordance with ASC 606 and concluded that the contract counterparty, Everest, is a customer based on the arrangement structure. The Company identified two material promises to deliver under the contract: (1) grant of license and the (2) clinical and commercial supply of the product. However, given the nature of the manufacturing of the product the license is not considered to be distinct from the clinical and commercial supply promise. The Company therefore concluded that there is one combined performance obligation. The Company initially deferred and will recognize the $65.0 million over the performance obligation period of the combined performance obligation. As it relates to the upfront consideration, the $65.0 million is recorded as deferred revenue and will be recognized over the term of the of the contract performance obligation period, which the Company has concluded to be 15 years after initial sale of the product in the territory. As concluded above, the Company has a combined performance obligation, which includes delivering the license and clinical and commercial supply to Everest. As such, because the clinical and commercial supply obligation occur throughout the period of the License Agreement, the $65.0 million fixed consideration is recognized over the period in which commercial and clinical supply of product is delivered (over-time). The future potential milestone payments are excluded from the transaction price, as the achievement of the milestone events require considerable judgment in determining whether it is probable of being achieved, and that a significant revenue reversal would not occur. As such, all milestone payments are fully constrained. The Company will reevaluate the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and, if necessary, adjust its estimate of the transaction price. Janssen Biotech Inc.: On April 5, 2019, the Company entered into a promotion agreement (the “Promotion Agreement”) with Janssen Biotech Inc., ("Janssen") pursuant to which the Company will provide non-exclusive product detailing services to Janssen for erdafitinib (the “Product”). Pursuant to the Promotion Agreement, the Company will provide a dedicated sales team to market the Product, upon approval by the FDA, to oncologists and other targeted health care providers in the United States. Under the terms of the Promotion Agreement, Janssen maintains ownership of the New Drug Application for the Product as well as legal, regulatory, distribution, commercialization and manufacturing responsibilities for the Product, while the Company will provide product detailing services to Janssen. Following the achievement of certain sales targets in 2019 and 2020, Janssen will pay the Company (a) a service fee equal to a percentage in the low double digits of the portion of Cumulative Net Sales (as defined in the Promotion Agreement) in excess of a baseline amount during each of 2019 and 2020, and (b) potential milestone payments of up to $15.0 million when Cumulative Net Sales exceed certain thresholds during each of 2019 and 2020. On April 12, 2019, the Company was informed that the FDA granted accelerated approval to Janssen's Balversa (erdafitinib) for the treatment of adult patients with locally advanced or metastatic urothelial carcinoma that has a type of susceptible genetic alteration known as FGFR3 or FGFR2, and that has progressed during or following prior platinum-containing chemotherapy. During the three and six months ended June 30, 2019 , no

Marketable Securities

Marketable Securities	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Marketable Securities Immunomedics considers all of its current investments to be available-for-sale. Marketable securities at June 30, 2019 , consisted of the following (in thousands): Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ (200 ) $ 4,741 Maturities of debt securities classified as available-for-sale were as follows at June 30, 2019 (in thousands): Fair Value Net Carrying Amount Due after one year through five years $ 4,741 $ 4,754 Marketable securities at December 31, 2018 consisted of the following (in thousands): Amortized Gross Gross Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ — $ 4,941 Maturities of debt securities classified as available-for-sale were as follows at December 31, 2018 (in thousands): Fair Value Net Carrying Due after one year through five years $ 4,941 $ 4,954

Debt

Debt	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Debt	Debt Liability related to sale of future royalties: On January 7, 2018, the Company entered into a funding agreement with RPI Finance Trust, a Delaware statutory trust ("RPI"), under which we sold a portion of our right to receive royalties on potential net sales of the ADC sacituzumab govitecan, in exchange for $175.0 million in cash. Concurrently, we entered into a common stock purchase agreement with RPI through which RPI purchased 4.4 million shares of the Company's common stock for $75.0 million (the "Financing"). The Company concluded that there were two units of accounting in the transaction: (1) the liability related to the sale of future royalties (the "Liability") and (2) the "Financing". We allocated the consideration of $250.0 million on a relative fair value basis to the Liability for $182.2 million and the common stock for $67.8 million . We continue to accrete the Liability related to the sale of future royalties using the effective interest method with an annual interest rate of approximately 18% over a period of 20 years. As of June 30, 2019 and December 31, 2018, we determined the fair value at $241.7 million and $221.3 million , respectively. During the three months ended June 30, 2019 and 2018, the Company recognized approximately $10.4 million and $9.2 million in interest expense, respectively. During the six months ended June 30, 2019 and 2018, the Company recognized approximately $20.4 million and $19.8 million in interest expense, respectively. The following table shows the activity within the liability related to sale of future royalties during the six months ended June 30, 2019 (in thousands): Carrying value of liability related to sale of future royalties at December 31, 2018 $ 221,295 Interest expense recognized 20,373 Carrying value of liability related to sale of future royalties at June 30, 2019 $ 241,668 Convertible Senior Notes: In February 2015, the Company issued $100.0 million of Convertible Senior Notes (the "Convertible Senior Notes") (net proceeds of approximately $96.3 million after deducting the initial purchasers’ fees and offering expenses) in a private offering exempt from registration under the Securities Act of 1933, as amended (the “Securities Act”), in reliance upon Rule 144A under the Securities Act. The Convertible Senior Notes will mature on February 15, 2020, unless earlier purchased or converted. The debt issuance costs of approximately $3.7 million , primarily consisting of underwriting, legal and other professional fees, are amortized over the term of the Convertible Senior Notes. The Convertible Senior Notes are senior unsecured obligations of the Company. Interest at 4.75% is payable semiannually on February 15 and August 15 of each year. The effective interest rate on the Convertible Senior Notes was 5.48% for the period from the date of issuance through June 30, 2019 . The balance of the outstanding Convertible Senior Notes was $7.1 million convertible into 1.4 million shares of common stock at June 30, 2019 , and December 31, 2018. If the Company undergoes a fundamental change (as defined in the indenture governing the Convertible Senior Notes), holders may require Immunomedics to purchase for cash all or part of the Convertible Senior Notes at a purchase price equal to 100% of the principal amount of the Convertible Senior Notes to be purchased, plus accrued and unpaid interest, if any, to, but excluding, the fundamental change purchase date, subject to certain exceptions. In addition, if certain make-whole fundamental changes (as defined in the indenture governing the Convertible Senior Notes) occur, Immunomedics will, in certain circumstances, increase the conversion rate for any Convertible Note converted in connection with such make-whole fundamental change. Total interest expense for the Convertible Senior Notes for the three months ended June 30, 2019 and 2018 was $0.1 million and $0.2 million , respectively. For the six months ended June 30, 2019 and 2018, interest expense was $0.2 million and $0.5 million , respectively. Included in interest expense was an immaterial amount of amortization of debt issuance costs for the three and six months ended June 30, 2019 and 2018.

Stock-based Compensation

Stock-based Compensation	6 Months Ended
	Jun. 30, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation	Stock-based Compensation Stock Incentive Plan The Company has a stock incentive plan, the Immunomedics, Inc. 2014 Long-Term Incentive Plan (the “Plan”) that provides for the granting of stock options, restricted stock units (RSUs), performance stock options (PSOs), and other stock-based awards to eligible individuals on the terms and subject to the conditions set forth in the Plan. There were no significant modifications to the Plan during the three and six months ended June 30, 2019 or 2018. Stock-based compensation expense included in the condensed consolidated statements of comprehensive loss was $2.4 million , and $1.4 million for the three months ended June 30, 2019 and 2018, respectively, and $4.1 million and $2.7 million for the six months ended June 30, 2019 and 2018. The following table summarizes the activity for stock options, RSUs and PSOs for the six months ended June 30, 2019 (in thousands): Stock Options RSUs PSOs Equity awards outstanding, beginning of year 4,757 15 538 Changes during the year: Granted 1,675 58 650 Exercised (1,140 ) (15 ) — Expired or forfeited (949 ) — (442 ) Equity awards outstanding, end of period 4,343 58 746 On March 14, 2019, performance stock options were granted to certain individuals that vest upon the Company’s receipt of approval from the FDA for the Company’s BLA for sacituzumab govitecan for the treatment of patients with metastatic triple-negative breast cancer who have received at least two prior therapies for metastatic disease under the Prescription Drug User Fee Act. There were additional stock options that were granted to certain eligible individuals that vest on the second anniversary of the date of grant. In addition, on April 17, 2019 performance stock options were granted to certain individuals that vest upon achievement of defined sales performance milestones. As of June 30, 2019 , total compensation cost related to unvested awards not yet recognized and the weighted-average periods over which the awards are expected to be recognized were as follows ($ in thousands): Stock Options RSUs PSOs Unrecognized compensation cost $ 33,988 $ 701 $ 5,556 Expected weighted-average period in years of compensation cost to be recognized 3.1 0.9 1.3

Estimated Fair Value of Financi

Estimated Fair Value of Financial Instruments	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Estimated Fair Value of Financial Instruments	Estimated Fair Value of Financial Instruments Cash equivalents and marketable securities as of: ($ in thousands) June 30, 2019 Level 1 (a) Level 2 (b) Level 3 (c) Total Money Market Funds Note (d) $ 330,422 $ — $ — $ 330,422 Marketable Securities: U.S. Government Sponsored Agencies 4,741 — — 4,741 Total $ 335,163 $ — $ — $ 335,163 ($ in thousands) December 31, 2018 Level 1 (a) Level 2 (b) Level 3 (c) Total Money Market Funds Note (d) $ 326,239 $ — $ — $ 326,239 Marketable Securities: U.S. Government Sponsored Agencies 4,941 — — 4,941 Total $ 331,180 $ — $ — $ 331,180 (a) Level 1 - Financial instruments whose values are based on unadjusted quoted prices for identical assets or liabilities in an active market which the company has the ability to access at the measurement date. (b) Level 2 - Financial instruments whose values are based on quoted market prices in markets where trading occurs infrequently or whose values are based on quoted prices of instruments with similar attributes in active markets. (c) Level 3 - Financial instruments whose values are based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement. These inputs reflect management's own assumptions about the assumptions a market participant would use in pricing the asset. (d) The money market funds noted above are included in cash and cash equivalents. Convertible Senior Notes The carrying amounts and estimated fair values (Level 2) of debt instruments are as follows (in thousands): As of June 30, 2019 As of December 31, 2018 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value Convertible Senior Notes $ 7,081 $ 19,600 $ 7,055 $ 20,100 The fair value of the Convertible Senior Notes, which differs from their carrying values, is influenced by interest rates, the Company’s stock price and stock price volatility, and is determined by prices for the Convertible Senior Notes observed in market trading which are Level 2 inputs. Liability related to the sale of future royalties The Company has determined the fair value of the liability related to the sale of future royalties is based on the Company's current estimates of future royalties expected to be paid to RPI, over the life of the arrangement, which are considered Level 3 (See Note 4 - "Debt"). There were no transfers between Level 1, Level 2, and Level 3 during the periods presented.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2019
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders’ Equity Common Stock On October 11, 2016, the Company completed an underwritten public offering of 10,000,000 shares of its common stock and accompanying warrants to purchase 10,000,000 shares of common stock at a purchase price of $3.00 per unit, comprising of one share of common stock and one warrant. The change in fair value of the warrant liabilities for the three and six months ended June 30, 2018 , resulted in a loss of approximately $58.9 million and $49.0 million , respectively, which has been recognized in the accompanying condensed consolidated statements of comprehensive loss. During 2018, all of the warrants were exercised. As of June 30, 2019 and December 31, 2018, there were no warrants outstanding. At-the-market Offering On March 29, 2019, the Company entered into a sales agreement (the "ATM Agreement") with Cowen and Company, LLC ("Cowen") to issue and sell shares of the Company’s common stock, par value $0.01 per share, having an aggregate offering price of up to $150,000,000 , from time to time during the term of the ATM Agreement, through an “at-the-market” equity offering program at the Company's sole discretion, under which Cowen will act as the Company’s agent and/or principal. The Company will pay Cowen a commission up to 3.0% of the gross sales proceeds of any common stock sold through Cowen under the ATM Agreement. During the three and six months ended June 30, 2019 , the Company sold 370,920 shares of common stock with net proceeds of $5.8 million at a weighted average price of $15.95 (excluding commissions) under the ATM Agreement. Treasury Stock During the six months ended June 30, 2019 , there were 84,896

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss The components of accumulated other comprehensive loss were as follows (in thousands): Currency Translation Adjustments Net Unrealized Gains (Losses) on Available- for-Sale Securities Accumulated Other Comprehensive Loss Balance, December 31, 2017 $ (323 ) $ (78 ) $ (401 ) Other comprehensive (loss) income before reclassifications (16 ) 64 48 Net current-period other comprehensive (loss) income (16 ) 64 48 Balance, June 30, 2018 $ (339 ) $ (14 ) $ (353 ) Balance, December 31, 2018 $ (347 ) $ (4 ) $ (351 ) Other comprehensive (loss) income before reclassifications (9 ) (200 ) (209 ) Reclassified gains from accumulated other comprehensive loss 195 — 195 Net current-period other comprehensive income (loss) 186 (200 ) (14 ) Balance, June 30, 2019 $ (161 ) $ (204 ) $ (365 ) There was $0.2 million reclassified from accumulated other comprehensive (loss) income during the three and six months ended June 30, 2019. All components of accumulated other comprehensive loss are net of tax, except currency translation adjustments, which exclude income taxes related to indefinite investments in foreign subsidiaries.

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2019
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions On January 8, 2018, Morris Rosenberg joined the Company as Chief Technology Officer and became a full-time employee. Between May 5, 2017 and January 7, 2018, Mr. Rosenberg was engaged by the Company as an independent consultant pursuant to a consulting agreement between the Company and Mr. Rosenberg’s consulting company, M Rosenberg BioPharma Consulting LLC. The Company paid M Rosenberg BioPharma Consulting LLC $0.6 million during this time and Morris Rosenberg was also granted stock options to purchase 45,000 shares of the Company's common stock pursuant to the Immunomedics, Inc. 2014 Long-Term Incentive Plan. From January 8, 2018 through June 30, 2018, the Company paid M Rosenberg BioPharma $0.8 million for services agreed upon prior to Mr. Rosenberg becoming a full-time employee. As part of his employment contract, 50% of the 45,000 shares granted to Mr. Rosenberg as a consultant were forfeited, and the remaining 50% continue to vest. Mr. Rosenberg received 104,389 stock options and was permitted to continue to provide certain limited outside consulting services through M Rosenberg BioPharma Consulting LLC based on certain restrictions outlined in the contract. Additionally, during his employment period, except with the prior written consent of the Company's Board of Directors (the "Board"), Mr. Rosenberg is not permitted to enter into any contract, agreement or other transaction arrangement to provide goods and/or services to the Company through M Rosenberg BioPharma Consulting LLC. The Company appointed Scott Canute, a member of the Company’s Board, as the Company’s Executive Director. Upon recommendation of the Compensation Committee, the Board approved that Mr. Canute will be paid $16,667 per month for his service as Executive Director and was granted a nonqualified stock option to purchase 79,818 shares of the Company’s common stock (the “Initial Canute Compensation”). The Compensation Committee determined that in order to reflect the scope of his role and the significant time that Mr. Canute will be devoting to his role as Executive Director, Mr. Canute’s cash compensation shall be increased to $21,372 per month, and Mr. Canute was granted an additional nonqualified stock option to purchase 22,854 shares of the Company’s common stock (the “Revised Canute Compensation”). The options have a seven -year term and an exercise price equal to the fair market value of the Company’s common stock based on the closing price of the Company’s common stock on each date of grant and will be subject to the terms of a nonqualified stock option agreement (the “Canute NQSO Agreement”). Such options will vest in full upon the Company’s receipt of approval from the FDA for the Company’s BLA resubmission for sacituzumab govitecan for the treatment of patients with TNBC who have received at least two prior therapies for metastatic disease under the PDUFA. The Company and Mr. Canute entered into a letter agreement (the “Canute Letter Agreement”) to memorialize his appointment as the Company’s Executive Director, and the Initial Canute Compensation. The Canute Letter Agreement may be terminated by either party at any time upon written notice to the other party. During the six months ended June 30, 2019 , the Company paid Mr. Canute $0.1 million

Collaboration Agreement

Collaboration Agreement	6 Months Ended
	Jun. 30, 2019
Collaboration Agreement [Abstract]
Collaboration Agreement	Collaboration Agreement AstraZeneca/MedImmune In June 2018, the Company entered into a clinical collaboration with AstraZeneca and its global biologics research and development arm, MedImmune, to evaluate in Phase 1/2 studies the safety and efficacy of combining AstraZeneca’s Imfinzi ® (durvalumab), a human monoclonal antibody directed against PD-L1, with sacituzumab govitecan as a treatment of patients with triple-negative breast cancer (“TNBC”) and urothelial cancer ("UC"), which was broadened in October 2018 to include second-line metastatic non-small cell lung cancer ("NSCLC"). Part one of the two-part Phase 1/2 studies will be co-funded by the two companies. Immunomedics will supply the study drug and AstraZeneca will utilize its existing clinical trial infrastructure to accelerate the enrollment of the sacituzumab govitecan and durvalumab combination. The trial design allows for rapid transition into randomized Phase 2 studies should the first part of these studies show promising data and the companies agree to proceed based on efficacy and safety results obtained. The Company did not incur costs associated with the clinical collaboration during the Transition Period. The collaboration terminates thirty days following the expiration of the study periods end-date. Either party may terminate the collaboration earlier by providing thirty days ' written notice.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments and Contingencies a. Legal Matters Stockholder Complaints: Class Action Stockholder Federal Securities Cases Two purported class action cases were filed in the United States District Court for the District of New Jersey; namely, Fergus v. Immunomedics, Inc., et al., filed June 9, 2016; and Becker v. Immunomedics, Inc., et al., filed June 10, 2016. These cases arise from the same alleged facts and circumstances, and seek class certification on behalf of purchasers of our common stock between April 20, 2016 and June 2, 2016 (with respect to the Fergus matter) and between April 20, 2016 and June 3, 2016 (with respect to the Becker matter). These cases concern the Company’s statements in press releases, investor conference calls, and filings with the U.S. Securities and Exchange Commission (the "SEC") beginning in April 2016 that the Company would present updated information regarding its IMMU-132 breast cancer drug at the 2016 American Society of Clinical Oncology (“ASCO”) conference in Chicago, Illinois. The complaints allege that these statements were false and misleading in light of June 2, 2016 reports that ASCO had canceled the presentation because it contained previously reported information. The complaints further allege that these statements resulted in artificially inflated prices for our common stock, and that the Company and certain of its officers are thus liable under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). An order of voluntary dismissal without prejudice was entered on November 10, 2016 in the Becker matter. An order granting motion to consolidate cases, appoint lead plaintiff, and approve lead and liaison counsel was entered on February 7, 2017 in the Fergus matter. A consolidated complaint was filed on October 4, 2017. The Company filed a motion to dismiss the consolidated complaint on January 26, 2018. On March 31, 2019, the court granted the Company's motion to dismiss, without prejudice, and left plaintiffs with the ability to file an amended complaint within thirty ( 30 ) days. Counsel for the Company has consented to an extension of time for plaintiffs to file the proposed amended complaint for an additional thirty ( 30 ) days. On May 30, 2019, plaintiffs filed an amended complaint alleging many of the same allegations that were set forth in the previously filed complaints, and the Company has filed a motion to dismiss. A third purported class action case was filed in the United States District Court for the District of New Jersey; namely, Odeh v. Immunomedics, Inc., et al., filed December 27, 2018. The complaint in this action alleges that the Company failed to disclose the results of observations made by the FDA during an inspection of the Company’s manufacturing facility in Morris Plains, New Jersey in August 2018. The complaint alleges that Immunomedics misled investors by failing to disclose the Form 483 inspection report issued by the FDA which set forth the observations of the FDA inspector during the inspection. Such observations purportedly included, inter alia, manipulated bioburden samples, misrepresentation of an integrity test procedure in the batch record, and backdating of batch records. The complaint further alleges that the Company’s failure to disclose the Form 483 resulted in an artificially inflated price for our common stock, and that the Company and certain of its officers are thus liable under Sections 10(b) and 20(a) of the Exchange Act. On February 8, 2019, a purported class action case was filed in the United States District Court for the District of New Jersey; namely, Choi v. Immunomedics, Inc., et al. The complaint asserts violations of the federal securities laws based on claims that the Company violated the federal securities laws by making alleged misstatements in various press releases and securities filings from February 8, 2018 to November 7, 2018 and by failing to disclose the substance of its interactions with the FDA in connection with the Company's submission of its BLA for sacituzumab govitecan. Motions for the appointment of a lead plaintiff and lead counsel and to consolidate the Odeh and Choi complaints have been filed. On April 8, 2019, a putative stockholder of the Company filed a derivative action purportedly on behalf of the Company and against the Company’s board of directors and certain Company current and former officers, in the Superior Court of New Jersey, Law Division (Morris County); namely, Crow v. Aghazadeh, et al. The Crow complaint alleges that the individual defendants breached their fiduciary duties and committed other violations of law based on the same core allegations in the Odeh and Choi actions. The Crow complaint was served on the Company and other defendants on July 18, 2019. Stockholder Claim in the Court of Chancery of the State of Delaware On February 13, 2017, venBio commenced an action captioned venBio Select Advisor LLC v. Goldenberg, et al., C.A. (Del. Ch.) (the “venBio Action”), alleging that Company’s Board breached their fiduciary duties when the Board (i) amended the Company’s Amended and Restated By-laws (the “By-Laws”) to call for a plurality voting regime for the election of directors instead of majority voting, and providing for mandatory advancement of attorneys’ fees and costs for the Company’s directors and officers, (ii) rescheduled the Company’s 2016 Annual Meeting of Stockholders (the “2016 Annual Meeting”) from December 14, 2016 to February 16, 2017, and then again to March 3, 2017, and (iii) agreed to the proposed Licensing Transaction with Seattle Genetics. venBio also named Seattle Genetics as a defendant and sought an injunction preventing the Company from closing the licensing transaction with Seattle Genetics. On March 6, 2017, venBio amended its complaint, adding further allegations. The Court of Chancery entered a temporary restraining order on March 9, 2017, enjoining the closing of the Licensing Transaction. venBio amended its complaint a second time on April 19, 2017, this time adding Greenhill & Co. Inc. and Greenhill & Co. LLC (together “Greenhill”), the Company’s financial advisor on the Licensing Transaction, as an additional defendant. On May 3, 2017, venBio and the Company and individual defendants Dr. Goldenberg, Ms. Sullivan and Mr. Brian A. Markison, a director of the Company (collectively, the “Individual Defendants”) entered into the Initial Term Sheet. On June 8, 2017, venBio the Company and Greenhill entered into the Greenhill Term Sheet. On February 9, 2018, the Court of Chancery approved the Settlement, and entered an order and partial judgment releasing all claims that were asserted by venBio against the Individual Defendants and Greenhill in the venBio Action and awarding venBio fees and expenses. On May 24, 2018 the remaining parties to the venBio Action participated in a mediation of the claims against Geoff Cox, Robert Forrester, Bob Oliver, and Jason Aryeh (the "Remaining Defendants"). The mediation was unsuccessful. The Remaining Defendants filed submitted motions to dismiss the claims against them in the venBio Action. On March 18, 2019, venBio amended its complaint, adding further allegations. The Remaining Defendants filed a motion to dismiss the claims against them on May 1, 2019. The Court of Chancery has scheduled oral arguments for the motion to dismiss on November 13, 2019. Insurance Coverage Arbitration: The Company has initiated an arbitration with three of its management liability insurers: Starr Indemnity & Liability Company (“Starr”), Liberty Insurance Underwriters Inc. (“Liberty”), and Berkley Professional Liability (“Berkley”) (collectively, “Insurers”). The arbitration arises from the Insurers’ refusal to cover $3,402,980 in attorneys’ fees and expenses paid to venBio pursuant to a December 1, 2017, settlement agreement between venBio, the Company, Dr. Goldenberg, Ms. Sullivan, Mr. Markison, and Greenhill to partially settle the venBio Action and fully settle the Federal Action and the Delaware Section 225 Action (the “venBio Fee Award”). The Insurers argue that the venBio Fee Award does not satisfy their policies’ definitions of covered “loss” because the policies only cover defense costs incurred by the Company. The Company counters that the venBio Fee Award is a covered settlement, not a claim for defense costs. Insurers also argue that they have no obligation to pay any defense costs or settlement incurred in the Federal Action or 225 Action because Immunomedics initiated those lawsuits. The Company’s position is that the Federal Action and 225 Action were defensive in nature and therefore covered because they were initiated to further the defense of the venBio Action. Additionally, Insurers argue the venBio Fee Award is not covered because the Company was required to obtain Insurers’ consent to enter into a binding term sheet in the venBio Action and to agree to pay the venBio Fee Award and that the Company failed to do so. The Company takes the position that Insurers at all times were aware of the developments in the venBio Action, that they sought consent to enter into the settlement, and that Insurers cannot show they were prejudiced by an any alleged failure to obtain Insurers’ consent. Liberty also contends that the Company’s insurance claim is not covered by Liberty’s 2015-16 insurance policy and should be covered by another company’s policy in a later policy period. The Company, Starr, and Berkley take the position that the policies treat the venBio Action as a related claim to the Fergus v. Immunomedics class action stockholder federal securities case, which was filed in 2016. Because of the similar allegation in the venBio Action and Fergus, the policies deem the venBio Action claim to be made at the same time as Fergus and covered by the 2015-16 policies. Starr is presently advancing the costs to defend the remaining claims in the venBio Action, i.e., those against the Company as Nominal Defendant and individual defendants Aryeh, Cox, Forrester, and Oliver. However, all Insurers have reserved their rights to contest coverage for any potential settlement of those claims. Breach of Contract: On November 16, 2018, Kapil Dhingra filed a complaint against Immunomedics, Inc., in the Superior Court of New Jersey, Law Division, Morris County, alleging breach of contract and breach of the implied covenant of good faith and fair dealing. In the complaint, Dhingra alleges that Immunomedics breached agreements with Dhingra entered into in 2012 and 2013 that purportedly give him the right to purchase 50,000 shares of Common Stock of Immunomedics for a strike price stated in the agreements. On January 11, 2019, Immunomedics filed a motion for summary judgment and to stay discovery while the motion for summary judgment was pending. On February 5, 2019, Dhingra filed an opposition brief and an amended complaint adding as a plaintiff Kapital Consulting, LLC (together with Dhingra, "Plaintiffs"), and Plaintiffs filed a partial cross-motion for summary judgment. On April 4, 2019, the Court denied all motions without prejudice pending the completion of discovery. Immunomedics continues to dispute the allegations and will seek expedited disposition following discovery. b. Other matters: Immunomedics is also a party to various claims and litigation arising in the normal course of business. c. Our Licenses We have obtained licenses from various parties for rights to use, develop and commercialize proprietary technologies and compounds. Currently, we have the following licenses: Medical Research Council (“MRC”) - We entered into a license agreement with MRC in May 1994, whereby we have obtained a license for certain patent rights with respect to the genetic engineering on monoclonal antibodies. Our agreement does not require any milestone payments, nor have we made any payments to MRC to date. Our agreement with MRC, which expires at the expiration of the last of the licensed patents in 2020, provides for future royalty payments in the low single digits based on a percentage of product sales. On April 4, 2018, we entered into a license agreement with The Scripps Research Institute ("TSRI"). Pursuant to the license agreement, TSRI granted to us an exclusive, worldwide, sub-licensable, royalty-bearing license to use certain patent rights relating to sacituzumab govitecan. The license agreement expires on a country-by-country basis on the expiration date of the last to expire licensed patent rights in such country covering a licensed product. The license agreement may be terminated by the mutual written consent of us and TSRI, and TSRI may terminate the license agreement upon the occurrence of certain events, including, but not limited to if we do not make a payment due pursuant to the license agreement and fail to cure such non-payment within 30 days after the date of TSRI's written notice of such non-payment. As consideration for the license granted, we made a cash payment of $250,000 to TSRI. Additionally, we will pay TRSI (i) product development milestone payments that range from the mid six-digit dollar figure to the low seven-digit dollar figure and (ii) royalties on net sales of licensed products in the low-single digit percentage figure range capped at an annual amount. We have agreed to use reasonable efforts to develop and market the licensed products. d. Michael Pehl Separation On March 13, 2019, the Company entered into a separation agreement (the “Separation Agreement”) with Michael Pehl, the Company’s former Chief Executive Officer, President and member of the Company’s Board. Mr. Pehl resigned as Chief Executive Officer, President and member of the Company’s Board effective February 23, 2019. Pursuant to the Separation Agreement, Mr. Pehl will receive cash payments of approximately $1.0 million over an eighteen-month period. During the six months ended June 30, 2019 , the Company paid approximately $0.1 million to Mr. Pehl, and $0.9 million was accrued for as of June 30, 2019 . Mr. Pehl also released the Company from any and all claims with respect to all matters arising out of or related to Mr. Pehl’s employment by the Company and his resignation. e. Leases Our operating lease assets primarily represent manufacturing and research and development facilities, warehouses, and offices. Our finance leases primarily represent computer equipment and are not significant. Total operating lease expense was $352,000 for the three months ended June 30, 2019 , and $705,000 for the six months ended June 30, 2019 . For the three and six months ended June 30, 2019 , cash payments against operating lease liabilities totaled $327,000 and $654,000 , respectively. The discount rate used to determine the net present value of the leases at inception was 11.0% . This is the incremental borrowing rate that represents the rate of interest that the Company would expect to pay to borrow an amount equal to the lease payments under similar terms. Our leases both share a remaining lease term of 12.3 years, some of which may include options to extend the leases further. The Company considers these options in determining the lease term used to establish the right-of-use assets and lease liabilities. Supplemental Unaudited Condensed Consolidated Balance Sheet information related to leases was as follows (in thousands): Operating leases: June 30, 2019 Operating lease right-of-use assets $ 8,239 Current portion of lease liabilities $ 271 Non-current portion of lease liabilities $ 10,138 Total operating lease liabilities $ 10,409 Weighted average remaining lease term (years) 12.3 Weighted average discount rate 11.0 % Supplemental cash flow information related to leases was as follows (in thousands): Six Months Ended June 30, 2019 Non-cash lease expense $ 130 Change in operating lease liabilities $ 79 Maturities of lease liabilities as of June 30, 2019 were as follows (in thousands): Year 1 $ 1,405 Year 2 1,453 Year 3 1,499 Year 4 1,523 Year 5 1,552 Thereafter 12,117 Total lease payments 19,549 Less imputed interest (9,140 ) Total $ 10,409

Business Overview, Basis of P_2

Business Overview, Basis of Presentation and Recent Accounting Pronouncements (Policies)	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Accounting Pronouncements adopted during the year: The Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2019-01, “Leases Topic 842,” requiring entities to recognize assets and liabilities on the balance sheet for all leases, with certain exceptions. Topic 842 allows for a modified retrospective application and is effective as of the first quarter of 2019. Entities are allowed to apply the new guidance using a modified retrospective approach at the beginning of the year in which new lease standard is adopted, rather than to the earliest comparative period presented in their financial statements. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. We elected the modified retrospective approach under the new guidance and elected the available practical expedients on adoption. Upon adoption, we recognized additional operating lease liabilities of $8.4 million with a corresponding right-of-use assets of $8.4 million based on the present value of the remaining lease payments under existing operating leases. As of December 31, 2018, we had $2.1 million in deferred charges related to our real estate leases that were recorded against the lease liability asset as part of the transition, resulting in $10.5 million included in other long-term liabilities on our condensed consolidated balance sheet. In addition, the new guidance resulted in additional lease-related disclosures in the footnotes to our condensed consolidated financial statements. Our leasing portfolio is comprised entirely of operating leases, and we do not recognize right-of-use assets or related lease liabilities with a lease term of twelve months or less on our condensed consolidated balance sheet. Adoption of Topic 842 has required changes to our business processes and controls to comply with the provisions of the standard. Refer to Note 11 "Commitments and Contingencies" for additional information. In June 2018, the FASB issued ASU 2018-07, "Compensation-Stock Compensation," to improve the usefulness of information provided to users of financial statements while reducing cost and complexity in financial reporting and provide guidance aligning the measurement and classification for share-based payments to nonemployees with the guidance for share-based payments to employees. Under the guidance, the measurement of equity-classified nonemployee awards will be fixed at the grant date. This standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. Early adoption is permitted, but no earlier than an entity's adoption date of ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).” We adopted ASU 2018-07 during the first quarter of 2019 and the adoption did not have a material impact to our condensed consolidated financial statements. Accounting Pronouncements yet to be adopted: In November 2018, the FASB issued ASU 2018-18, "Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606," to clarify when ASC 606 should be used for collaborative arrangements when the counterparty is a customer. The guidance precludes an entity from presenting consideration from a transaction in a collaborative arrangement as revenue from contracts with customers if the counterparty is not a customer for that transaction. The guidance is effective for public business entities in fiscal years beginning after December 15, 2019, and interim periods therein. Early adoption is permitted to entities that have adopted ASC 606. We are currently assessing the impact of ASU 2018-18. In August 2018, the FASB issued ASU 2018-13, "Fair Value measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement," to no longer require public companies to disclose transfers between Level 1 and Level 2 of the fair value hierarchy, and to require disclosure about the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. The guidance is effective for fiscal years beginning after December 15, 2019, and for interim periods within those fiscal years. Entities are permitted to early adopt either the entire standard or only the provisions that eliminate or modify the requirements. We are currently assessing the impact of ASU 2018-13.

Marketable Securities (Tables)

Marketable Securities (Tables)	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Schedule of maturities of available-for-sale debt securities	Maturities of debt securities classified as available-for-sale were as follows at June 30, 2019 (in thousands): Fair Value Net Carrying Amount Due after one year through five years $ 4,741 $ 4,754 Maturities of debt securities classified as available-for-sale were as follows at December 31, 2018 (in thousands): Fair Value Net Carrying Due after one year through five years $ 4,941 $ 4,954
Schedule of marketable securities	Marketable securities at December 31, 2018 consisted of the following (in thousands): Amortized Gross Gross Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ — $ 4,941 June 30, 2019 , consisted of the following (in thousands): Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ (200 ) $ 4,741

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Schedule of deferred revenue, by arrangement	The following table shows the activity within the liability related to sale of future royalties during the six months ended June 30, 2019 (in thousands): Carrying value of liability related to sale of future royalties at December 31, 2018 $ 221,295 Interest expense recognized 20,373 Carrying value of liability related to sale of future royalties at June 30, 2019 $ 241,668

Stock-based Compensation (Table

Stock-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of stock option activity	The following table summarizes the activity for stock options, RSUs and PSOs for the six months ended June 30, 2019 (in thousands): Stock Options RSUs PSOs Equity awards outstanding, beginning of year 4,757 15 538 Changes during the year: Granted 1,675 58 650 Exercised (1,140 ) (15 ) — Expired or forfeited (949 ) — (442 ) Equity awards outstanding, end of period 4,343 58 746
Schedule of RSU and PSU activity	The following table summarizes the activity for stock options, RSUs and PSOs for the six months ended June 30, 2019 (in thousands): Stock Options RSUs PSOs Equity awards outstanding, beginning of year 4,757 15 538 Changes during the year: Granted 1,675 58 650 Exercised (1,140 ) (15 ) — Expired or forfeited (949 ) — (442 ) Equity awards outstanding, end of period 4,343 58 746
Schedule of compensation cost related to unvested awards	As of June 30, 2019 , total compensation cost related to unvested awards not yet recognized and the weighted-average periods over which the awards are expected to be recognized were as follows ($ in thousands): Stock Options RSUs PSOs Unrecognized compensation cost $ 33,988 $ 701 $ 5,556 Expected weighted-average period in years of compensation cost to be recognized 3.1 0.9 1.3

Estimated Fair Value of Finan_2

Estimated Fair Value of Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Schedule of cash equivalents and marketable securities	Cash equivalents and marketable securities as of: ($ in thousands) June 30, 2019 Level 1 (a) Level 2 (b) Level 3 (c) Total Money Market Funds Note (d) $ 330,422 $ — $ — $ 330,422 Marketable Securities: U.S. Government Sponsored Agencies 4,741 — — 4,741 Total $ 335,163 $ — $ — $ 335,163 ($ in thousands) December 31, 2018 Level 1 (a) Level 2 (b) Level 3 (c) Total Money Market Funds Note (d) $ 326,239 $ — $ — $ 326,239 Marketable Securities: U.S. Government Sponsored Agencies 4,941 — — 4,941 Total $ 331,180 $ — $ — $ 331,180 (a) Level 1 - Financial instruments whose values are based on unadjusted quoted prices for identical assets or liabilities in an active market which the company has the ability to access at the measurement date. (b) Level 2 - Financial instruments whose values are based on quoted market prices in markets where trading occurs infrequently or whose values are based on quoted prices of instruments with similar attributes in active markets. (c) Level 3 - Financial instruments whose values are based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement. These inputs reflect management's own assumptions about the assumptions a market participant would use in pricing the asset. (d) The money market funds noted above are included in cash and cash equivalents.
Schedule of convertible senior notes	The carrying amounts and estimated fair values (Level 2) of debt instruments are as follows (in thousands): As of June 30, 2019 As of December 31, 2018 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value Convertible Senior Notes $ 7,081 $ 19,600 $ 7,055 $ 20,100

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Schedule of components of accumulated other comprehensive loss	The components of accumulated other comprehensive loss were as follows (in thousands): Currency Translation Adjustments Net Unrealized Gains (Losses) on Available- for-Sale Securities Accumulated Other Comprehensive Loss Balance, December 31, 2017 $ (323 ) $ (78 ) $ (401 ) Other comprehensive (loss) income before reclassifications (16 ) 64 48 Net current-period other comprehensive (loss) income (16 ) 64 48 Balance, June 30, 2018 $ (339 ) $ (14 ) $ (353 ) Balance, December 31, 2018 $ (347 ) $ (4 ) $ (351 ) Other comprehensive (loss) income before reclassifications (9 ) (200 ) (209 ) Reclassified gains from accumulated other comprehensive loss 195 — 195 Net current-period other comprehensive income (loss) 186 (200 ) (14 ) Balance, June 30, 2019 $ (161 ) $ (204 ) $ (365 )

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of supplemental lease information	Supplemental Unaudited Condensed Consolidated Balance Sheet information related to leases was as follows (in thousands): Operating leases: June 30, 2019 Operating lease right-of-use assets $ 8,239 Current portion of lease liabilities $ 271 Non-current portion of lease liabilities $ 10,138 Total operating lease liabilities $ 10,409 Weighted average remaining lease term (years) 12.3 Weighted average discount rate 11.0 % Supplemental cash flow information related to leases was as follows (in thousands): Six Months Ended June 30, 2019 Non-cash lease expense $ 130 Change in operating lease liabilities $ 79
Schedule of lease liability	Maturities of lease liabilities as of June 30, 2019 were as follows (in thousands): Year 1 $ 1,405 Year 2 1,453 Year 3 1,499 Year 4 1,523 Year 5 1,552 Thereafter 12,117 Total lease payments 19,549 Less imputed interest (9,140 ) Total $ 10,409

Business Overview, Basis of P_3

Business Overview, Basis of Presentation and Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Total operating lease liabilities	$ 10,409
Operating lease right-of-use assets	8,239
Other long-term liabilities	$ 10,138		$ 2,119
ASU 2016-02
Lessee, Lease, Description [Line Items]
Total operating lease liabilities		$ 8,400
Operating lease right-of-use assets		8,400
Other long-term liabilities		$ 10,500

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Details) - USD ($)	Apr. 29, 2019	Apr. 05, 2019	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Deferred revenues			$ 65,000,000	$ 65,000,000	$ 0
Everest Medicines II Limited
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Upfront fees paid	$ 65,000,000
Milestone payment, achievement of FDA approval for sacituzumab govitecan	60,000,000
Milestone payment, sales	530,000,000
Remaining performance obligation	65,000,000
Deferred revenues	$ 65,000,000
Everest Medicines II Limited | Minimum
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Royalty payments	14.00%
Everest Medicines II Limited | Maximum
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Milestone payment, development	$ 180,000,000
Royalty payments	20.00%
Janssen Biotech Inc.
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Milestone payment, sales		$ 15,000,000
Revenues			$ 0	$ 0

Revenue Recognition - Performan

Revenue Recognition - Performance Obligation (Details) - Everest Medicines II Limited $ in Millions	Apr. 29, 2019USD ($)
Revenue Recognition, Milestone Method [Line Items]
Remaining performance obligation	$ 65
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-07-01
Revenue Recognition, Milestone Method [Line Items]
Remaining performance obligation	$ 65
Term of license agreement	15 years

Marketable Securities - Amortiz

Marketable Securities - Amortized Cost to Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 4,741	$ 4,941
U.S. Government Sponsored Agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,941	4,941
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	(200)	0
Fair Value	$ 4,741	$ 4,941

Marketable Securities - Maturit

Marketable Securities - Maturity Schedule (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Fair value, due after one year through five years	$ 4,741	$ 4,941
Net carrying amount, due after one year through five years	$ 4,754	$ 4,954

Debt - Liability Related To Sal

Debt - Liability Related To Sale of Future Royalties (Details) - USD ($) $ in Thousands, shares in Millions	Jan. 07, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Common stock		$ 1,920		$ 1,920		$ 1,905
RPI Finance Trust | Funding agreement
Debt Instrument [Line Items]
Payments for future royalties	$ 175,000
Royalty purchase agreement arrangements consideration	250,000
Liability related to sale of future royalties	182,200	241,700		241,700		221,300
Common stock	$ 67,800
Annual interest rate in calculating liability related to sale of future royalties	18.00%
Period which company will accrete the liability	20 years
Interest expense recognized		10,400	$ 9,200	20,400	$ 19,800
Private placement | RPI Finance Trust | Funding agreement
Debt Instrument [Line Items]
Stock issued during period (in shares)	4.4
Sale of stock, consideration received on transaction	$ 75,000
Royalty Arrangement | RPI Finance Trust
Debt Instrument [Line Items]
Liability related to sale of future royalties		$ 241,668		241,668		$ 221,295
Interest expense recognized				$ 20,373

Debt - Convertible Notes (Detai

Debt - Convertible Notes (Details) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 28, 2015USD ($)	Jun. 30, 2019USD ($)$ / shares	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)$ / shares	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)$ / sharesshares
Debt Instrument [Line Items]
Non-cash component of warrant exercise				$ 0	$ 137,979,000
Common stock, par value (in usd per share) | $ / shares		$ 0.01		$ 0.01		$ 0.01
Outstanding balance on debt conversion		$ 7,100,000		$ 7,100,000		$ 1,400,000
Interest expense				$ 20,373,000	19,790,000
Convertible Senior Notes
Debt Instrument [Line Items]
Face amount	$ 100,000,000
Proceeds from debt, net of issuance costs	96,300,000
Payments of debt issuance costs	$ 3,700,000
Stated interest rate	4.75%
Effective interest rate		5.48%		5.48%
Conversion ratio				0.1958
Outstanding balance on debt conversion						$ 7,100,000
Shares convertible into common shares (in shares) | shares						1.4
Interest expense		$ 100,000	$ 200,000	$ 200,000	$ 500,000

Stock-based Compensation - Narr

Stock-based Compensation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based compensation expense	$ 2.4	$ 1.4	$ 4.1	$ 2.7

Stock-based Compensation - Awar

Stock-based Compensation - Award Activity (Details) - shares shares in Thousands	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Equity awards outstanding, beginning of year (in shares)	4,757
Granted (in shares)	1,675
Exercised (in shares)	(1,140)
Expired or forfeited (in shares)	(949)
Equity awards outstanding, end of period (in shares)	4,343
RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Equity awards outstanding, beginning of year (in shares)	58	15
Granted (in shares)	58
Exercised (in shares)	(15)
Expired or forfeited (in shares)	0
Equity awards outstanding, end of period (in shares)	58
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Equity awards outstanding, beginning of year (in shares)	746	538
Granted (in shares)	650
Exercised (in shares)	0
Expired or forfeited (in shares)	(442)
Equity awards outstanding, end of period (in shares)	746

Stock-based Compensation - Comp

Stock-based Compensation - Compensation Cost Related to Unvested Awards (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019USD ($)
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 33,988
Expected weighted-average period in years of compensation cost to be recognized	3 years 1 month 6 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 701
Expected weighted-average period in years of compensation cost to be recognized	10 months 24 days
PSOs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 5,556
Expected weighted-average period in years of compensation cost to be recognized	1 year 3 months 18 days

Estimated Fair Value of Finan_3

Estimated Fair Value of Financial Instruments - Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 335,163	$ 331,180
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	335,163	331,180
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Money Market Funds Note
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money Market Funds Note	330,422	326,239
Money Market Funds Note | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money Market Funds Note	330,422	326,239
Money Market Funds Note | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money Market Funds Note	0	0
Money Market Funds Note | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money Market Funds Note	0	0
U.S. Government Sponsored Agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Government Sponsored Agencies	4,741	4,941
U.S. Government Sponsored Agencies | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Government Sponsored Agencies	4,741	4,941
U.S. Government Sponsored Agencies | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Government Sponsored Agencies	0	0
U.S. Government Sponsored Agencies | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Government Sponsored Agencies	$ 0	$ 0

Estimated Fair Value of Finan_4

Estimated Fair Value of Financial Instruments - Convertible Senior Notes (Details) - Convertible Senior Notes - Level 2 - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible Senior Notes	$ 7,081	$ 7,055
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible Senior Notes	$ 19,600	$ 20,100

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($)	Mar. 29, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Oct. 11, 2016
Class of Warrant or Right [Line Items]
Common stock, par value (in usd per share)		$ 0.01		$ 0.01		$ 0.01
Changes in fair value of warrant liabilities		$ 0	$ 58,861,000	$ 0	$ 49,026,000
IPO
Class of Warrant or Right [Line Items]
Number of securities called by warrants or rights (in shares)							10,000,000
Common stock, par value (in usd per share)							$ 3
Warrants outstanding (in shares)		0		0		0
ATM Agreement
Class of Warrant or Right [Line Items]
Common stock, par value (in usd per share)	$ 0.01
Sale of stock, consideration received on transaction	$ 150,000,000
Percentage of payments for stock issuance costs	3.00%
Sale of stock (in shares)				370,920
Proceeds from sale of stock				$ 5,800,000
Sales Agreement
Class of Warrant or Right [Line Items]
Value of non-cash consideration received (in shares)		84,896
Weighted Average | ATM Agreement
Class of Warrant or Right [Line Items]
Shares issued (in usd per share)		$ 15.95		$ 15.95

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning Balance	$ 181,804	$ 71,820	$ 265,849	$ 16,450
Other comprehensive (loss) income before reclassifications			(209)	48
Other comprehensive loss, net of tax:	195	104	(14)	48
Ending Balance	114,560	399,686	114,560	399,686
Reclassification from AOCI	200		195
Currency Translation Adjustments
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning Balance			(347)	(323)
Other comprehensive (loss) income before reclassifications			(9)	(16)
Other comprehensive loss, net of tax:			186	(16)
Ending Balance	(161)	(339)	(161)	(339)
Reclassification from AOCI			195
Net Unrealized Gains (Losses) on Available- for-Sale Securities
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning Balance			(4)	(78)
Other comprehensive (loss) income before reclassifications			(200)	64
Other comprehensive loss, net of tax:			(200)	64
Ending Balance	(204)	(14)	(204)	(14)
Reclassification from AOCI			0
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning Balance	(560)	(457)	(351)	(401)
Other comprehensive loss, net of tax:	195	104	(14)	48
Ending Balance	$ (365)	$ (353)	$ (365)	$ (353)

Related Party Transactions (Det

Related Party Transactions (Details)	Mar. 08, 2019USD ($)shares	Mar. 05, 2019USD ($)shares	Jun. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018shares	Jan. 06, 2018USD ($)shares	Jul. 01, 2018
Related Party Transaction [Line Items]
Percent of stock-based compensation shares retired							0.50
Percent of stock-based compensation shares that continue to vest			0.50
Chief Technology Officer
Related Party Transaction [Line Items]
Non-qualifed stock options granted (in shares)					104,389
Executive Director
Related Party Transaction [Line Items]
Non-qualifed stock options granted (in shares)	22,854	79,818
Term of options	7 years
Board of Directors
Related Party Transaction [Line Items]
Officers' compensation | $	$ 21,372	$ 16,667	$ 100,000
M Rosenberg Bio Pharma Consulting LLC
Related Party Transaction [Line Items]
Professional and contract service expense | $				$ 800,000		$ 600,000
Non-qualifed stock options granted (in shares)						45,000
Non-qualified stock options forfeited (in shares)						45,000

Collaboration Agreement (Detail

Collaboration Agreement (Details)	6 Months Ended
	Jun. 30, 2019
Collaboration Agreement [Abstract]
Number of days following the expiration of the study periods end-date that the collaboration terminates	30 days
Days notice required for collaboration termination	30 days

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	Mar. 08, 2019USD ($)	Mar. 05, 2019USD ($)	Nov. 16, 2018shares	Apr. 04, 2018USD ($)	Jun. 09, 2016case	Jun. 30, 2019USD ($)	Jun. 30, 2019USD ($)issuer
Loss Contingencies [Line Items]
Class action cases (in cases) | case					2
Number of days to file a complaint						30 days
Number of issuers arbitration initiated with (issuers) | issuer							3
Right of termination prior written notice period				30 days
Payment for contingent consideration liability				$ 250,000
Time period supplemental unemployment benefits to be paid							18 months
Chief Executive Officer
Loss Contingencies [Line Items]
Severance benefits						$ 1,000,000	$ 1,000,000
Officers' compensation							100,000
Salary accrued						$ 900,000	900,000
Insurance Coverage Arbitration
Loss Contingencies [Line Items]
Damages sought							3,402,980
Dhingra Agreement | Restricted Units With Vesting Market Conditions
Loss Contingencies [Line Items]
Restricted stock expense (in shares) | shares			50,000
Director
Loss Contingencies [Line Items]
Officers' compensation	$ 21,372	$ 16,667					$ 100,000

Commitments and Contingencies_2

Commitments and Contingencies - Leases (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Lease expense	$ 352	$ 705
Cash payments against operating lease liabilities	327	654
Operating lease right-of-use assets	8,239	8,239
Current portion of lease liabilities	271	271
Total operating lease liabilities	$ 10,409	$ 10,409
Weighted average remaining lease term (years)	12 years 3 months 18 days	12 years 3 months 18 days
Weighted average discount rate	11.00%	11.00%
Non-cash lease expense		$ 130
Change in operating lease liabilities		79
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Year 1	$ 1,405	1,405
Year 2	1,453	1,453
Year 3	1,499	1,499
Year 4	1,523	1,523
Year 5	1,552	1,552
Thereafter	12,117	12,117
Total lease payments	19,549	19,549
Less imputed interest	(9,140)	(9,140)
Total	10,409	10,409
Other long-term liabilities	$ 10,138	$ 10,138	$ 2,119

Uncategorized Items - immu-6302

Label	Element	Value
Restricted Cash and Cash Equivalents, Current	us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue	$ 1,313,000
Restricted Cash and Cash Equivalents, Current	us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue	$ 525,000