ImmunityBio (IBRX) 10-Q 9 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Nov. 05, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Trading Symbol	NK
Entity Registrant Name	NANTKWEST, INC.
Entity Central Index Key	0001326110
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth Company	true
Entity Small Business	true
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		108,592,583
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity File Number	001-37507
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	43-1979754
Entity Address, Address Line One	3530 John Hopkins Court
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92121
City Area Code	858
Local Phone Number	633-0300
Document Quarterly Report	true
Document Transition Report	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 27,688	$ 15,508
Prepaid expenses and other current assets (including amounts with related parties)	8,977	4,105
Marketable debt securities, available-for-sale	61,353	36,144
Total current assets	98,018	55,757
Marketable debt securities, noncurrent	769	1,497
Property, plant and equipment, net (including amounts with related parties)	55,864	60,501
Operating lease right-of-use assets, net (including amounts with related parties)	14,602	11,729
Equity investment	9,253	9,253
Other assets (including amounts with related parties)	2,029	4,386
Total assets	180,535	143,123
Current liabilities:
Accounts payable	6,160	1,749
Accrued expenses	5,497	5,343
Due to related parties	1,356	486
Operating lease liabilities (including amounts with related parties)	5,351	3,206
Other current liabilities	2,299	775
Total current liabilities	20,663	11,559
Operating lease liabilities, less current portion (including amounts with related parties)	11,250	10,885
Total liabilities	31,913	22,444
Commitments and contingencies (Note 8)	0	0
Stockholders’ equity:
Common stock, $0.0001 par value; 500,000,000 shares authorized; 108,592,583 and 98,460,404 issued and outstanding as of September 30, 2020 and December 31, 2019, respectively	11	10
Additional paid-in capital	871,170	782,965
Accumulated other comprehensive loss	(117)	(105)
Accumulated deficit	(722,442)	(662,191)
Total stockholders’ equity	148,622	120,679
Total liabilities and stockholders’ equity	$ 180,535	$ 143,123

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	108,592,583	98,460,404
Common stock, shares outstanding	108,592,583	98,460,404

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Revenue	$ 68	$ 12	$ 90	$ 34
Operating expenses:
Research and development (including amounts with related parties)	17,284	12,052	44,227	37,781
Selling, general and administrative (including amounts with related parties)	4,711	4,025	16,603	13,949
Total operating expenses	21,995	16,077	60,830	51,730
Loss from operations	(21,927)	(16,065)	(60,740)	(51,696)
Other income (expense):
Investment income, net	66	433	319	1,336
Interest expense	(9)	(5)	(19)	(8)
Other income, net (including amounts with related parties)	96	56	195	186
Total other income	153	484	495	1,514
Loss before income taxes	(21,774)	(15,581)	(60,245)	(50,182)
Income tax (expense) benefit	(2)	0	(6)	34
Net loss	$ (21,776)	$ (15,581)	$ (60,251)	$ (50,148)
Net loss per share:
Basic and diluted	$ (0.20)	$ (0.16)	$ (0.59)	$ (0.54)
Weighted-average number of shares during the period:
Basic and diluted	108,246,579	98,331,695	101,853,047	92,791,644

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (21,776)	$ (15,581)	$ (60,251)	$ (50,148)
Other comprehensive (loss) income, net of income taxes:
Net unrealized (losses) gains on available-for-sale securities	(19)	27	(14)	210
Reclassification of net realized losses on available-for-sale securities included in net loss	2	4	2	4
Total other comprehensive (loss) income	(17)	31	(12)	214
Comprehensive loss	$ (21,793)	$ (15,550)	$ (60,263)	$ (49,934)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balance at Dec. 31, 2018	$ 146,006	$ 8	$ 741,246	$ (267)	$ (594,981)
Beginning Balance, Shares at Dec. 31, 2018		79,087,734
Stock-based compensation expense	2,150	$ 0	2,150	0	0
Exercise of warrants	35,151	$ 2	35,149	0	0
Exercise of warrants, Shares		17,589,250
Exercise of stock options	4,070	$ 0	4,070	0	0
Exercise of stock options, Shares		1,986,300
Vesting of restricted stock units (RSUs)	0	$ 0	0	0	0
Vesting of restricted stock units (RSUs), Shares		247,601
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options	(66)	$ 0	(66)	0	0
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options, Shares		(70,115)
Repurchase of common stock	$ (501)	$ 0	0	0	(501)
Repurchase of common stock, Shares	(473,586)	(473,586)
Cumulative effect of the adoption of the new lease standard | Accounting Standards Update 2016-02	$ (920)	$ 0	0	0	(920)
Other comprehensive income (loss), net	214	0	0	214	0
Net loss	(50,148)	0	0	0	(50,148)
Ending Balance at Sep. 30, 2019	135,956	$ 10	782,549	(53)	(646,550)
Ending Balance, Shares at Sep. 30, 2019		98,367,184
Beginning Balance at Jun. 30, 2019	151,269	$ 10	782,312	(84)	(630,969)
Beginning Balance, Shares at Jun. 30, 2019		98,307,859
Stock-based compensation expense	277	$ 0	277	0	0
Vesting of restricted stock units (RSUs)	0	$ 0	0	0	0
Vesting of restricted stock units (RSUs), Shares		90,310
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options	(40)	$ 0	(40)	0	0
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options, Shares		(30,985)
Other comprehensive income (loss), net	31	$ 0	0	31	0
Net loss	(15,581)	0	0	0	(15,581)
Ending Balance at Sep. 30, 2019	135,956	$ 10	782,549	(53)	(646,550)
Ending Balance, Shares at Sep. 30, 2019		98,367,184
Beginning Balance at Dec. 31, 2019	$ 120,679	$ 10	782,965	(105)	(662,191)
Beginning Balance, Shares at Dec. 31, 2019	98,460,404	98,460,404
Issuance of common stock, net	$ 86,302	$ 1	86,301	0	0
Issuance of common stock, net, Shares		8,521,500
Stock-based compensation expense	1,472	$ 0	1,472	0	0
Exercise of stock options	917	$ 0	917	0	0
Exercise of stock options, Shares		1,142,273
Vesting of restricted stock units (RSUs)	0	$ 0	0	0	0
Vesting of restricted stock units (RSUs), Shares		642,236
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options	$ (485)	$ 0	(485)	0	0
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options, Shares		(173,830)
Repurchase of common stock, Shares	0
Other comprehensive income (loss), net	$ (12)	$ 0	0	(12)	0
Net loss	(60,251)	0	0	0	(60,251)
Ending Balance at Sep. 30, 2020	$ 148,622	$ 11	871,170	(117)	(722,442)
Ending Balance, Shares at Sep. 30, 2020	108,592,583	108,592,583
Beginning Balance at Jun. 30, 2020	$ 169,653	$ 11	870,408	(100)	(700,666)
Beginning Balance, Shares at Jun. 30, 2020		107,764,158
Issuance of common stock, net	19	$ 0	19	0	0
Stock-based compensation expense	711	0	711	0	0
Exercise of stock options	353	$ 0	353	0	0
Exercise of stock options, Shares		883,256
Vesting of restricted stock units (RSUs)	0	$ 0	0	0	0
Vesting of restricted stock units (RSUs), Shares		83,260
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options	(321)	$ 0	(321)	0	0
Employee payroll taxes withheld related to vesting of RSUs and exercise of stock options, Shares		(138,091)
Other comprehensive income (loss), net	(17)	$ 0	0	(17)	0
Net loss	(21,776)	0	0	0	(21,776)
Ending Balance at Sep. 30, 2020	$ 148,622	$ 11	$ 871,170	$ (117)	$ (722,442)
Ending Balance, Shares at Sep. 30, 2020	108,592,583	108,592,583

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Statement Of Stockholders Equity [Abstract]
Offering costs	$ 4,373	$ 4,373

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities:
Net loss	$ (60,251)	$ (50,148)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	6,864	6,803
Non-cash lease expense related to operating lease right-of-use assets	2,290	1,925
Stock-based compensation expense	1,472	2,150
Amortization of net premiums and discounts on marketable debt securities	425	(11)
Loss on sales of marketable debt securities	2	5
Non-cash interest items, net	(288)	173
Loss on impairment of fixed assets	0	869
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(2,291)	9,176
Other assets	116	(2,961)
Accounts payable	4,253	342
Accrued expenses and other liabilities	1,574	(11,622)
Due to related parties	1,091	(839)
Operating lease liabilities	(2,654)	(2,339)
Net cash used in operating activities	(47,397)	(46,477)
Investing activities:
Purchases of property, plant and equipment	(2,238)	(3,502)
Purchase of Viracta common stock	0	(3)
Purchases of marketable debt securities, available-for-sale	(85,581)	(76,831)
Maturities of marketable debt securities	54,080	87,100
Sales of marketable debt securities	6,582	2,529
Net cash (used in) provided by investing activities	(27,157)	9,293
Financing activities:
Proceeds from equity offering, net of issuance costs paid	86,302	0
Proceeds from exercises of stock options	917	4,070
Proceeds from exercises of warrants	0	35,151
Repurchase of common stock	0	(501)
Net share settlement for restricted stock unit vesting	(485)	(66)
Net cash provided by financing activities	86,734	38,654
Net increase in cash, cash equivalents, and restricted cash	12,180	1,470
Cash, cash equivalents, and restricted cash, beginning of period	15,687	17,000
Cash, cash equivalents, and restricted cash, end of period	27,867	18,470
Reconciliation of cash, cash equivalents, and restricted cash at end of period:
Cash and cash equivalents	27,688	18,291
Restricted cash	179	179
Cash, cash equivalents, and restricted cash, end of period	27,867	18,470
Supplemental disclosure of cash flow information:
Interest	19	8
Income taxes	6	3
Supplemental disclosure of non-cash activities:
Property and equipment purchases included in accounts payable, accrued expenses and due to related parties	339	188
Cashless exercise of stock options	1,233	29
Right-of-use assets obtained in exchange for operating lease liabilities	5,164	800
Conversion of Viracta convertible notes and accrued interest into investment in equity securities of Viracta (Note 4)	0	751
Unrealized (losses) gains on marketable debt securities	$ (12)	$ 271

Description of Business

Description of Business	9 Months Ended
	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business	1. Description of Business Organization NantKwest, Inc., or NantKwest, was incorporated in Illinois on October 7, 2002 under the name ZelleRx Corporation. On January 22, 2010, the company changed its name to Conkwest, Inc., and on July 10, 2015, the company changed its name to NantKwest, Inc. In March 2014, the company redomesticated from the State of Illinois to the State of Delaware and the Illinois company ceased to exist. We are a pioneering clinical-stage immunotherapy biotechnology company headquartered in San Diego, California with certain operations in Culver City and El Segundo, California and Woburn, Massachusetts. In these notes, the terms “we,” “our,” “the company” and “us” refer to NantKwest. We are focused on harnessing the power of the innate immune system by using our natural killer cells, or NK cells, to treat cancer and viral infectious diseases. A critical aspect of our strategy is to invest significantly in innovating new therapeutic candidates, based upon our proprietary activated NK, or aNK, cell platform, and conducting clinical testing and scale manufacturing of our most promising biologic product candidates. We hold the exclusive right to commercialize aNK cells, a commercially viable NK cell line, and a wide range of genetically modified derivatives capable of killing cancer and virally infected cells. We own corresponding United States, or U.S., and foreign composition and methods-of-use patents and applications covering the cells, improvements, methods of expansion and manufacture and use of aNK cells and their improvements as therapeutics to treat a spectrum of clinical conditions. We also license exclusive commercial rights to a high-affinity CD16 receptor expressing enhancement of our aNK cell platform, covered in a portfolio of U.S. and foreign composition and methods-of-use patents and applications covering both the clinical use as a therapeutic to treat cancers in combination with antibody products, as well as the non-clinical use in laboratory testing of monoclonal antibodies. We have non-exclusively licensed or sub-licensed our high-affinity CD16 bearing aNK cell platform and corresponding intellectual property to numerous pharmaceutical and biotechnology companies for such non-clinical uses. Liquidity On June 29, 2020, the company closed an underwritten public offering of an aggregate of 8,521,500 shares of common stock, which included 4,811,500 shares issued to the public at a price of $9.50 per share (which includes 1,111,500 shares sold to the public upon full exercise of the underwriters’ option to purchase additional shares at a public offering price of $9.50 per share), less underwriting discounts and commissions, and 3,710,000 shares issued to our Chairman and principal stockholder, Dr. Patrick Soon-Shiong, at a price of $12.12 per share, less underwriting discounts and commissions. All of the shares were offered by the company. Including the underwriters’ option exercise, the aggregate gross proceeds from the offering were approximately $90.7 million, before deducting underwriting discounts, commissions and other offering expenses of approximately $4.4 million. As of September 30, 2020, the company had an accumulated deficit of $722.4 million. We also had negative cash flow from operations of $47.4 million during the nine months ended September 30, 2020. The company will likely need additional capital to further fund development of, and seek regulatory approvals for, our product candidates, and to begin to commercialize any approved products. We are currently focused primarily on the development of immunotherapeutic treatments for cancers and debilitating viral infections using targeted cancer and viral killing cell lines, and we believe such activities will result in the company’s continued incurrence of significant research and development and other expenses related to those programs. If the clinical trials for any of the company’s product candidates fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of our product candidates, if approved, fail to achieve market acceptance, we may never become profitable. Even if the company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. We intend to cover our future operating expenses through cash and cash equivalents and marketable debt securities on hand and through a combination of equity offerings, debt financings, government or other third-party funding, marketing and distribution arrangements and other collaborations, strategic alliances, and licensing arrangements. Additional financing may not be available to us when needed and, if available, financing may not be obtained on terms favorable to the company or its stockholders. While we expect our existing cash, and cash equivalents and marketable debt securities will enable us to fund operations and capital expenditure requirements for at least the next 12 months, we anticipate that we will need additional funds to reach commercialization. Failure to obtain adequate financing when needed may require us to delay, reduce, limit, or terminate some or all of our development programs or future commercialization efforts or grant rights to develop and market product candidates that we might otherwise prefer to develop and market ourselves, which could adversely affect our ability to operate as a going concern. If we raise additional funds from the issuance of equity securities, substantial dilution to existing stockholders may result. If we raise additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations , as well as covenants and specific financial ratios that may restrict our ability to operate our business.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies There have been no material changes in our significant accounting policies other than the adoption of accounting pronouncements described below under Application of New or Revised Accounting Standards – Adopted Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP and pursuant to the rules and regulations of the Securities and Exchange Commission. The unaudited condensed consolidated financial statements reflect all adjustments which are, in the opinion of management, necessary for a fair presentation of our financial position and results of operations. The unaudited condensed consolidated financial statements do not include all information and notes required by U.S. GAAP for annual reports. Accordingly, these financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the fiscal year ended December 31, 2019 included in our Annual Report on Form 10‑K. Interim operating results are not necessarily indicative of operating results for the full year. The condensed consolidated financial statements have been prepared assuming the company will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or amounts and classification of liabilities that may result from the outcome of the uncertainty discussed in the Liquidity section of Note 1. We believe our existing cash, cash equivalents, and investments in marketable debt securities, will be sufficient to fund operations through at least the next 12 months following the issuance date of the financial statements. We may also seek to sell additional equity, through one or more follow-on public offerings, or in separate financings, or obtain a credit facility. However, we may not be able to secure such financing in a timely manner or on favorable terms. Without additional funds, we may choose to delay or reduce our operating or investment expenditures. Further, because of the risk and uncertainties associated with the commercialization of the company’s product candidates in development, we may need additional funds to meet our needs sooner than planned. Principles of Consolidation and Equity Investments The condensed consolidated financial statements include the accounts of NantKwest and its wholly owned subsidiaries. All intercompany amounts have been eliminated. We apply the variable interest model under Accounting Standards Codification, or ASC, Topic 810, Consolidation For entities we hold as an equity investment that are not consolidated under the VIE model, we consider whether our investment constitutes ownership of a majority of the voting interests in the entity and therefore should be considered for consolidation under the voting interest model. Unconsolidated equity investments in the common stock or in-substance common stock of an entity under which we are able to exercise significant influence, but not control, are accounted for using the equity method. Our ability to exercise significant influence is generally indicated by ownership of 20 to 50 percent interest in the voting securities of the entity. All other unconsolidated equity investments on which we are not able to exercise significant influence will be subsequently measured at fair value with unrealized holding gains and losses included in other income, net , on the condensed consolidated statements of operations. In the instance the equity investment does not have a readily determinable fair value and does not qualify for the practical expedient to estimate fair value in accordance with ASC 820, Fair Value Measurement , or ASC 820, we will apply the measurement alternative under ASC 321, Investments—Equity Securities , or ASC 321 , pursuant to which we will measure the investment at its cost less impairment, adjusted for observable price changes in an orderly market for an identical or similar investment of the same issuer. We own non-marketable equity securities that are accounted for using the measurement alternative under ASC 321 because the preferred stock held by us is not considered in-substance common stock and such preferred stock does not have a readily determinable fair value. All investments are reviewed on a regular basis for possible impairment. If an investment's fair value is determined to be less than its net carrying value, the investment is written down to its fair value. Such an evaluation is judgmental and dependent on specific facts and circumstances. Factors considered in determining whether an impairment indicator is present include: the investees’ earnings performance and clinical trial performance, change in the investees’ industry and geographic area in which it operates, offers to purchase or sell the security for a price less than the cost of the investment, issues that raise concerns about the investee's ability to continue as a going concern, and any other information that we may be aware of related to the investment. Factors considered in determining whether an observable price change has occurred include: the price at which the investee issues equity instruments similar to those of our investment and the rights and preferences of those equity instruments compared to ours. Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, we evaluate our estimates, including those related to valuation of equity-based awards, deferred income taxes and related valuation allowances, preclinical and clinical trial accruals, impairment assessments, the measurement of right-of-use assets and lease liabilities, useful lives of long-lived assets, loss contingencies, and fair value measurements. We base our estimates on historical experience and on various other market-specific and relevant assumptions that we believe to be reasonable under the circumstances. Estimates are assessed each period and updated to reflect current information, such as the economic considerations related to the impact that the ongoing coronavirus pandemic could have on our significant accounting estimates. Actual results could differ from those estimates. Risks and Uncertainties In March 2020, the World Health Organization declared the novel strain of coronavirus disease (SARS‑CoV‑2) outbreak a pandemic. To date, our operations have not been significantly impacted by the pandemic. However, we cannot at this time predict the specific extent, duration, or full impact that this pandemic may have on our financial condition and results of operations, including ongoing and planned clinical trials. More specifically, the pandemic may result in prolonged impacts that we cannot predict at this time and we expect that such uncertainties will continue to exist until such time a vaccine is broadly available and in use. The impact of the pandemic on the financial performance of the company will depend on future developments, including the duration and spread of the outbreak and related governmental advisories and restrictions. These developments and the impact of the ongoing pandemic on the financial markets and the overall economy are highly uncertain. If the financial markets and/or the overall economy are impacted for an extended period, our results may be adversely affected. Contingencies We record accruals for loss contingencies to the extent that we conclude it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. We evaluate, on a quarterly basis, developments in legal proceedings and other matters that could cause a change in the potential amount of the liability recorded or of the range of potential losses disclosed. Moreover, we record gain contingencies only when they are realizable, and the amount is known. Additionally, we record our rights to insurance recoveries, limited to the extent of incurred or probable losses, as a receivable when such recoveries have been agreed to with our third-party insurers and when receipt is deemed probable. This includes instances when our third-party insurers have agreed to pay, on our behalf, certain legal defense costs and settlement amounts directly to applicable law firms and a settlement fund. Concentration of Credit Risk and Other Risks and Uncertainties Financial instruments that potentially subject us to concentrations of risk consist principally of cash and cash equivalents and marketable debt securities. Our cash and cash equivalents are held by one major financial institution in the U.S. and one in Korea. Product candidates developed by us will require approvals or clearances from the U.S. Food and Drug Administration , or FDA , or international regulatory agencies prior to commercial sales. There can be no assurance that any of our product candidates will receive any of the required approval s or clearance s . If we w ere to be denied approval or clearance or any such approval or clearance w as to be delayed, it would have a material adverse impact on us . Basic and Diluted Net Loss per Share of Common Stock Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted loss per share is computed similarly to basic loss per share except that the denominator is increased to include the number of additional shares that would have been outstanding if the potential common shares had been issued and if the additional common shares were dilutive. For all periods presented, potentially dilutive securities are excluded from the computation of fully diluted loss per share as their effect is anti-dilutive. The following table details those securities that have been excluded from the computation of potentially dilutive securities: As of September 30, 2020 2019 Outstanding options 3,648,010 4,506,950 Outstanding RSUs 480,292 1,273,278 Total 4,128,302 5,780,228 Amounts in the table above reflect the common stock equivalents of the noted instruments. Collaboration Arrangements We analyze our collaboration arrangements to assess whether they are within the scope of ASC Topic 808, Collaborative Arrangements, Revenue from Contracts with Customers Our collaboration arrangements require us to acquire certain equipment for exclusive use in the joint operating activities. These equipment purchases do not have an alternative use and are therefore expensed as incurred within research and development expenses. Our collaboration arrangements are further discussed within Note 7, Collaboration and License Agreements Recent Accounting Pronouncements Application of New or Revised Accounting Standards – Adopted In November 2018, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2018-18, Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606 Collaboration and License Agreements In December 2019, the FASB issued A SU 2019 ‑ 12, Simplifying the Accounting for Income Taxes , or ASU 2019 ‑12 . The amendments in ASU 2019 ‑ 12 include remov ing the exception to the incremental approach for intraperiod tax allocation when there is a loss from continuing operations and income or a gai n from other items (e.g., discontinued operations or other comprehensive income) , and the exception to the general methodology for calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year . ASU 2019 ‑ 12 also amends other aspects of accounting for income taxes to help simplify and promote consistent application of U.S. GAAP . The guidance is effective for interim and annual periods beginning after December 15, 2020, with early adoption permitted. We early adopted ASU 2019 ‑ 12 effective January 1, 2020, and it did not have a material impact on our consolidated financial statements . Although our adoption of ASU 2019 ‑12 did not have a material impact on our consolidated financial statements during the three and nine months ended September 30, 2020 , it may have a material impact on our consolidated financial statements in future periods due to the removal of the exceptions discussed above. The amendment s related to intraperiod tax allocation were a pplied prospectively, and the amendment related to calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year will be applied prospectively. Application of New or Revised Accounting Standards – Not Yet Adopted In June 2016, the FASB issued ASU 2016‑13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Other recent authoritative guidance issued by the FASB (including technical corrections to the ASC), the American Institute of Certified Public Accountants, and the Securities and Exchange Commission during the three months ended September 30, 2020 did not, or are not expected to, have a material effect on our consolidated financial statements.

Financial Statement Details

Financial Statement Details	9 Months Ended
	Sep. 30, 2020
Financial Statement Details [Abstract]
Financial Statement Details	3. Financial Statement Details Prepaid expenses and other current assets As of September 30, 2020 and December 31, 2019, prepaid expenses and other current assets were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Prepaid preclinical and clinical trial services - with related party (Note 9) $ 3,262 $ 1,021 Insurance premium financing asset 2,262 757 Prepaid services 825 440 Prepaid insurance 657 372 Interest receivable - marketable debt securities 510 222 Prepaid rent 422 392 Prepaid supplies - with related party (Note 9) 306 467 Prepaid license fees 216 78 Prepaid equipment maintenance 165 251 Laboratory equipment deposit 162 — Due from related parties 100 47 Insurance claim receivables — 34 Other 90 24 $ 8,977 $ 4,105 Property, p lant and e quipment, n et As of September 30, 2020 and December 31, 2019, property, plant and equipment, net, was made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Leasehold improvements $ 33,665 $ 33,406 Buildings 22,690 22,690 Equipment 22,738 21,434 Software 1,190 1,195 Furniture & fixtures 415 383 80,698 79,108 Accumulated depreciation (24,834 ) (18,607 ) $ 55,864 $ 60,501 Depreciation expense related to property, plant and equipment was $2.4 million and $2.2 million for the three months ended September 30, 2020 and 2019, respectively, and $6.9 million and $6.2 million for the nine months ended September 30, 2020 and 2019, respectively. Other assets As of September 30, 2020 and December 31, 2019, other assets were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Prepaid preclinical and clinical trial services - with related party (Note 9) $ 1,570 $ 4,075 Restricted cash 179 179 Prepaid software license fees 118 — Security deposit 113 113 Other 49 19 $ 2,029 $ 4,386 Restricted cash is comprised of a certificate of deposit that serves as collateral for a letter of credit required by our landlord as a security deposit related to our facility in San Diego, California. Accrued expenses As of September 30, 2020 and December 31, 2019, accrued expenses were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Accrued bonus $ 1,838 $ 2,002 Accrued compensation 1,113 1,064 Accrued professional and service fees 829 975 Accrued laboratory equipment, supplies and related services 635 640 Accrued preclinical and clinical trial costs 627 281 Accrued franchise and sales/use taxes 217 200 Accrued construction costs 164 — Other 74 181 $ 5,497 $ 5,343 Other c urrent l iabilities As of September 30, 2020 and December 31, 2019, other current liabilities were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Financing obligation - current portion $ 2,262 $ 757 Other 37 18 $ 2,299 $ 775 Investment income, net Net investment income is as follows for the three and nine months ended September 30, 2020 and 2019 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 (Unaudited) (Unaudited) Interest income $ 449 $ 424 $ 795 $ 1,325 Investment (amortization expense) accretion income, net (381 ) 13 (474 ) 15 Net realized losses on investments (2 ) (4 ) (2 ) (4 ) $ 66 $ 433 $ 319 $ 1,336 Interest income includes interest from marketable debt securities, notes receivable, other assets, and interest from bank deposits. We did not recognize an impairment loss on any investments during the three and nine months ended September 30, 2020 and 2019.

Viracta Investment

Viracta Investment	9 Months Ended
	Sep. 30, 2020
Investments All Other Investments [Abstract]
Viracta Investment	4. Viracta Investment In March 2017, we participated in a Series B convertible preferred stock financing and invested $8.5 million in Viracta Therapeutics, Inc., or Viracta, a clinical stage drug development company. In May 2017, we executed an exclusive worldwide license with Viracta to develop and commercialize Viracta’s proprietary histone deacetylase inhibitor drug candidate for use in combination with natural killer cell therapy and possibly additional therapies. At September 30, 2020, our investment in Viracta totaled $9.3 million. Our investment in Viracta is reflected in equity investment on the condensed consolidated balance sheets. In June 2018, Viracta executed a 2018 Note and Warrant Purchase Agreement with existing and new investors, including us. The initial closing under the Purchase Agreement occurred in June 2018, at which point we purchased a convertible note for $0.4 million, which under certain circumstances was convertible into preferred stock of Viracta, and a warrant to purchase Viracta’s common shares. The convertible note accrued interest at 8% and had a one-year one-year Based on the level of equity investment at risk, Viracta is not a VIE and therefore is not consolidated under the VIE model. In addition, we do not hold a controlling financial interest in Viracta and therefore we do not consolidate Viracta under the voting interest model. As the preferred stock is not considered in-substance common stock, the investment is not within the scope of accounting for the investment under the equity method. As the preferred stock does not have a readily determinable fair value and does not qualify for the practical expedient to estimate fair value in accordance with ASC 820, we have elected to apply the measurement alternative under ASC 321, pursuant to which we measure our investment in Viracta at cost, less impairment, adjusted for observable price changes in an orderly market for an identical or similar investment of the same issuer. As of September 30, 2020, our qualitative impairment assessment did not indicate there were events or changes in circumstances that may have had a significant adverse effect on the fair value of the investment. We have not recorded any impairments as of September 30, 2020, or on a cumulative basis. Further, we have not identified any downward or upward adjustments due to observable price changes in the investment as of September 30, 2020, or on a cumulative basis.

Financial Instruments Investmen

Financial Instruments Investments in Debt Securities	9 Months Ended
	Sep. 30, 2020
Cash Equivalents And Marketable Securities [Abstract]
Financial Instruments Investments in Marketable Debt Securities	5. Financial Instruments – Investments in Marketable Debt Securities At September 30, 2020, our investments in available-for-sale debt securities, excluding $10.6 million of corporate debt securities and commercial paper included in cash and cash equivalents, are detailed below (in thousands): September 30, 2020 (Unaudited) Amortized Cost Unrealized Gains Unrealized Losses Fair Value Current: Corporate debt securities $ 57,367 $ 3 $ (16 ) $ 57,354 Commercial paper 3,998 1 — 3,999 Current portion 61,365 4 (16 ) 61,353 Noncurrent: Corporate debt securities 769 — — 769 Noncurrent portion 769 — — 769 Total $ 62,134 $ 4 $ (16 ) $ 62,122 At September 30, 2020, the weighted-average remaining contractual life of our available-for-sale securities was approximately 0.5 years. At December 31, 2019, our investments in available-for-sale debt securities are detailed below (in thousands): December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Current: Corporate debt securities $ 32,382 $ 10 $ (3 ) $ 32,389 Foreign government bonds 1,007 — — 1,007 Government sponsored securities 2,752 — (4 ) 2,748 Current portion 36,141 10 (7 ) 36,144 Noncurrent: Corporate debt securities 1,501 — (4 ) 1,497 Noncurrent portion 1,501 — (4 ) 1,497 Total $ 37,642 $ 10 $ (11 ) $ 37,641 Accumulated unrealized losses on debt securities classified as available-for-sale that have been in a continuous loss position for less than 12 months and for more than 12 months September 30, 2020 (Unaudited) Less than 12 months More than 12 months Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Corporate debt securities $ 33,238 $ (16 ) $ — $ — Total $ 33,238 $ (16 ) $ — $ — December 31, 2019 Less than 12 months More than 12 months Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Corporate debt securities $ 11,021 $ (3 ) $ 1,497 $ (4 ) Government sponsored securities — — 2,748 (4 ) Total $ 11,021 $ (3 ) $ 4,245 $ (8 ) We evaluated our securities for other-than-temporary impairment and concluded that the decline in value was primarily caused by current economic and market conditions. We do not intend to sell the investments and it is not more likely than not that we will be required to sell the investments before recovery of their amortized cost bases. Therefore, we did not recognize any other-than-temporary impairment loss during the nine months ended September 30, 2020 . Realized gains and losses on sales of available-for-sale debt securities during the three and nine months ended September 30, 2020 and 2019 were immaterial.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	6. Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, based on our principal or, in absence of a principal, most advantageous market for the specific asset or liability. We use a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis, as well as assets and liabilities measured at fair value on a non-recurring basis, in periods subsequent to their initial measurement. The hierarchy requires us to use observable inputs when available, and to minimize the use of unobservable inputs, when determining fair value. The three tiers are defined as follows: • Level 1— Observable inputs that reflect quoted market prices (unadjusted) for identical assets or liabilities in active markets at the measurement date. Since valuations are based on quoted prices that are readily and regularly available in an active market, valuation of these products does not entail a significant degree of judgment. Our Level 1 assets consist of bank deposits and money market funds. • Level 2— Observable inputs other than quoted prices in active markets that are observable either directly or indirectly in the marketplace for identical or similar assets and liabilities. Our Level 2 assets consist of corporate debt securities including commercial paper, government sponsored securities and corporate bonds, as well as foreign municipal securities. • Level 3— Valuations based on inputs that are unobservable and significant to the overall fair value measurement. During the periods presented, no transfers were made into or out of the Level 1, 2 or 3 categories. We will continue to review the fair value inputs on quarterly basis. We utilize a third-party pricing service to assist in obtaining fair value pricing for our investments in marketable debt securities. Inputs are documented in accordance with the fair value disclosure hierarchy. Recurring Valuations Financial assets and liabilities measured at fair value on a recurring basis are summarized below at September 30, 2020 and December 31, 2019 (in thousands): Fair Value Measurements at September 30, 2020 (Unaudited) Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents $ 27,688 $ 17,100 $ 10,588 $ — Corporate debt securities 57,354 — 57,354 — Commercial paper 3,999 — 3,999 — Noncurrent: Corporate debt securities 769 — 769 — Total assets measured at fair value $ 89,810 $ 17,100 $ 72,710 $ — Fair Value Measurements at December 31, 2019 Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents $ 15,508 $ 15,508 $ — $ — Corporate debt securities 32,389 — 32,389 — Foreign government bonds 1,007 — 1,007 — Government sponsored securities 2,748 — 2,748 — Noncurrent: Corporate debt securities 1,497 — 1,497 — Total assets measured at fair value $ 53,149 $ 15,508 $ 37,641 $ — Non-recurring Valuations Non-financial assets and liabilities are recognized at fair value subsequent to initial recognition when they are deemed to be other-than-temporarily impaired. There were no material non-financial assets and liabilities deemed to be other-than-temporarily impaired and measured at fair value on a non-recurring basis for the three months ended September 30, 2020.

Collaboration and License Agree

Collaboration and License Agreements	9 Months Ended
	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaboration and License Agreements	7. Collaboration and License Agreements Collaborative Arrangements A collaborative arrangement is a contractual arrangement that involves a joint operating activity. These arrangements involve two or more parties who are (i) active participants in the activity, and (ii) exposed to significant risks and rewards dependent on the commercial success of the activity. We have entered into the following collaborative arrangements with ImmunityBio, Inc., ImmunityBio, and/or its subsidiaries as described below. ImmunityBio is a related party, as it is an affiliate of NantWorks (Note 9). Joint COVID‑19 Collaboration Development Agreement On August 21, 2020, we entered into a definitive agreement (the “Collaboration Agreement”) with ImmunityBio to pursue collaborative joint development, manufacturing and marketing of certain COVID‑19 therapeutics and vaccines. The terms of the Collaboration Agreement supersede and replace the terms of the binding term sheet executed on May 22, 2020, as previously disclosed. Through their efforts, the parties agreed to jointly develop ceNK, haNK, mesenchymal stem cells (MSC), adenovirus constructs (hAd5), and N‑803, a novel IL‑15 cytokine superagonist, for the prevention and treatment of SARS‑CoV‑2 viral infections and associated conditions in humans, including without limitation, COVID‑19. Pursuant to the Collaboration Agreement, we have contributed our ceNK, haNK, and MSC product candidates and certain of our manufacturing capabilities, and ImmunityBio has contributed their hAd5 and N‑803 product candidates. hAd5 has been developed as a vaccine, and ceNK, haNK, MSC and N‑803 have each been developed as therapeutics for treating COVID‑19 at various stages of infection. From and after the effective date of the Collaboration Agreement, the parties will share equally in all costs relating to developing and manufacturing of the product candidates globally with the exception of certain laboratory equipment purchases that will be borne solely by us. With the exception of N‑803, we will be primarily responsible for the manufacture of each product. Each party will be responsible for the regulatory affairs and the commercialization relating to its contributed products. The global net profits from the collaboration products will be shared 60%/40% in favor of the party contributing the product on which the sales are based except if the parties mutually agree because of certain circumstances. All net profits from sales of combined collaboration products will be shared equally. This collaboration is supervised by a joint steering committee, which is comprised of an equal number of representatives from both parties. The term of the agreement will be five years and it is renewable for an additional five year period upon mutual agreement. Each party will also have a right to terminate in the event of material breach, bankruptcy, or insolvency. At September 30, 2020, joint research activity under the Collaboration Agreement totaled $3.5 million, which has been included in research and development expense on the condensed consolidated statements of operations. Expenses incurred during the third quarter of 2020 were primarily related to the acquisition of $3.2 million of equipment to be utilized in the manufacture of the hAd5 COVID‑19 vaccine candidate, and other net program related costs of $0.3 million after applying the eligible cost sharing under the Collaboration Agreement. Certain equipment purchases made by us during the third quarter of 2020, which are necessary for us to fulfil our manufacturing obligations related to the COVID‑19 program, were borne solely by us. These equipment purchases do not have an alternative use and were therefore expensed as incurred within research and development expenses. Prior to the effective date of the Collaboration Agreement, COVID‑19 related program costs incurred by us and ImmunityBio, including expenditures related to property, plant and equipment, were the responsibility of each party and not subject to the equal cost sharing. At September 30, 2020, we owed ImmunityBio $0.1 million for net costs incurred under the Collaboration Agreement, which has been included in due to related parties on the condensed consolidated balance sheets. Cost Sharing Agreement In January 2020, but effective on October 1, 2019, we entered into a Cost Allocation Agreement with ImmunityBio and its subsidiaries to co-sponsor and conduct certain combination clinical trials (each a Joint Study) pursuant to clinical trial protocols wherein at least one investigational agent is a proprietary therapeutic drug candidate owned or controlled by NantKwest and at least one other investigational agent is a proprietary therapeutic drug candidate owned or controlled by ImmunityBio. Prior to initiating any activities for a Joint Study the parties agreed to enter into written work orders describing, amongst other things, development and management responsibilities, allocation of Joint Study costs and expenses, regulatory responsibilities, and any other matters relating to the Joint Study. Under the Cost Allocation Agreement, each of ImmunityBio and the company will receive exclusive rights to any new intellectual property developed that relates solely to its respective study drug, and the parties will have joint co-equal rights in any other intellectual property. The Cost Allocation Agreement expires on June 22, 2022 with the option to renew for additional successive one-year We and ImmunityBio are splitting certain costs related to these joint studies equally in accordance with the terms of the Cost Allocation Agreement and related work orders. Shared Joint Study costs include cost related to conducting the Joint Study development activities, such as personnel related costs, as well as all costs associated with regulatory matters. Costs and expenses incurred in connection with the development, manufacturing, supply, delivery, and pre-patient administration dosing mechanism of each party’s study drug, are excluded from the shared Joint Study costs. In January 2020, but effective on October 1, 2019, we executed Work Order Number One with ImmunityBio, pursuant to the Cost Allocation Agreement. Under Work Order Number One, the parties are conducting a clinical trial pursuant to the protocol titled QUILT 3.063: A phase 2 study of combination therapy with an IL‑15 superagonist (N‑803), off-the-shelf CD16‑targeted natural killer cells (haNK), and avelumab without cytotoxic chemotherapy in subjects with Merkel Cell Carcinoma (MCC) that has progressed on or after treatment with a checkpoint inhibitor In July 2020, but effective on June 22, 2020, we executed Work Order Number Two with ImmunityBio, pursuant to the Cost Allocation Agreement. Under Work Order Number Two, the parties are conducting a clinical trial pursuant to the protocol titled QUILT 88: Open-label, randomized, comparative phase 2 study of combination immunotherapy with standard-of-care chemotherapy versus standard-of-care chemotherapy for first and second line treatment of locally or advanced metastatic pancreatic cancer During the three and nine months ended September 30, 2020, we incurred net costs of $0.3 million and $0.5 million, respectively, after applying the eligible costs sharing under the Cost Allocation Agreement, which have been recognized in research and development expense on the condensed consolidated statements of operations. At September 30, 2020, our balance owed to ImmunityBio related to the Cost Allocation Agreement was not material. Exclusive Co-Development Agreement In August 2016, we entered into an exclusive Co‑Development Agreement, or the Co‑Development Agreement, with Altor BioScience, LLC, or Altor. Altor is a related party, as it is a wholly owned subsidiary of ImmunityBio (Note 9). Under the Co‑Development Agreement, the parties agreed to exclusively collaborate on the development of certain therapeutic applications combining our proprietary NK cells with Altor's N‑801 and/or N‑803 products with respect to certain technologies and intellectual property rights as may be agreed between the parties for the purpose of jointly developing therapeutic applications of certain effector cell lines. We are the lead developer for each product developed by the parties pursuant to the Co‑Development Agreement unless otherwise agreed to under a given project plan. Under the terms of the Co‑Development Agreement, both parties granted a co-exclusive, royalty free, fully paid-up, worldwide license, with the right to sublicense (only to a third-party contractor assisting with research and development activities under this Co‑Development Agreement and subject to prior consent, not to be unreasonably withheld), under the intellectual property, or IP, including the parties interest in the joint IP, solely to conduct any development activities agreed to by the steering committee as set forth in any development plan. Unless otherwise mutually agreed by the parties in the development plan for a project, we are responsible for all costs and expenses incurred by either party related to conducting clinical trials and other activities under each development program, including costs associated with patient enrollment, materials and supplies, third-party staffing and regulatory filings. Altor supplies free of charge, sufficient amounts of Altor products for all pre-clinical requirements and certain clinical requirements for up to 400 patients in phase I and/or phase II clinical trials, as required under the development plan for a project per the Co‑Development Agreement. Each company owns an undivided interest in and to all rights, title and interest in and to the joint product rights. The Co‑Development Agreement expires upon the fifth anniversary of the effective date. We have dosed patients with N‑803, an IL‑15 superagonist, in several phase Ib/II trials. No charges for supplies by Altor were incurred in association with the above trials during the three and nine months ended September 30, 2020 and 2019.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies Contingencies We record accruals for loss contingencies to the extent that we conclude it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. We evaluate, on a quarterly basis, developments in legal proceedings and other matters that could cause a change in the potential amount of the liability recorded or of the range of potential losses disclosed. Moreover, we record gain contingencies only when they are realizable, and the amount is known. Additionally, we record our rights to insurance recoveries, limited to the extent of incurred or probable losses, as a receivable when such recoveries have been agreed to with our third-party insurers and when receipt is deemed probable. This includes instances where our third-party insurers have agreed to pay, on our behalf, certain legal defense costs and settlement amounts directly to applicable law firms and a settlement fund. Securities Litigation In March 2016, a putative securities class action complaint captioned Sudunagunta v. NantKwest, Inc., et al. Under the terms of the settlement, we paid $12.0 million to the plaintiffs as full and complete settlement of the litigation. We were responsible for $1.2 million of the settlement amount, which was recognized in selling, general and administrative expense during 2018, while the remaining $10.8 million was fully funded by our insurance carriers under our directors’ and officers’ insurance policy. We and the insurance carriers paid the settlement amount into a settlement fund in January 2019. Subsequent to receiving final approval of the settlement on May 31, 2019, the aforementioned settlement accrual, associated insurance claim receivable and restricted cash were released and are no longer reflected on the accompanying condensed consolidated balance sheets. Stipulation of Settlement In early April 2019, following board approval, we entered into a settlement agreement, or the Stipulation of Settlement, with three stockholders of the company, each of whom had submitted a stockholder demand for the board to take action to remedy purported harm to the company resulting from certain alleged wrongful conduct concerning, among other things, disclosures about Dr. Soon-Shiong’s compensation and a related-party lease agreement. The Stipulation of Settlement called for us to adopt certain governance changes, and for the three stockholders to file a stockholder derivative action in the Superior Court of the State of California, County of San Diego, followed by an application for court approval of the Stipulation of Settlement. On May 31, 2019, the court entered an order preliminarily approving the Stipulation of Settlement and scheduling the final settlement hearing for August 9, 2019. Pursuant to the Stipulation of Settlement, we have provided stockholders with notice of the settlement and the final settlement hearing. Under the terms of the Stipulation of Settlement, which received final approval by the court on August 9, 2019, we paid an attorney’s fee of $0.5 million to the plaintiffs as part of the settlement. Of that amount, we were responsible for half, which was recognized in selling, general and administrative expense on the condensed consolidated statements of operations during the first quarter of 2019, while the other half was funded by our insurance carrier. We and the insurance carrier paid the settlement amount into a settlement fund in June 2019. Subsequent to receiving final approval of the settlement on August 9, 2019, the aforementioned settlement accrual, associated insurance claim receivable and restricted cash were released and are no longer reflected on the accompanying condensed consolidated balance sheets. Insurance Recoveries We have reflected our right to insurance recoveries, limited to the extent of incurred or probable losses, as a receivable when such recoveries have been agreed to with our third-party insurers and receipt is deemed probable. This includes instances where our third-party insurers have agreed to pay, on our behalf, certain legal defense costs and settlement amounts directly to applicable law firms and a settlement fund. The amount of such receivable recorded at December 31, 2019 was $34,000, which is included in prepaid expenses and other current assets on our consolidated balance sheets. There were no such receivables recorded at September 30, 2020. Contractual Obligations - Leases Substantially all of our operating lease right-of-use assets and operating lease liabilities relate to facilities leases. We lease: (i) a research facility and office space in San Diego, California; (ii) a research and manufacturing space in Culver City, California, from a related party; (iii) research and manufacturing facilities in El Segundo, California, also from related parties; (iv) a research facility in Torrance, California; and (v) a research facility in Woburn, Massachusetts. See Note 9 – Related Party Agreements For the three months ended September 30, 2020 and 2019, $1.7 million and $1.3 million, respectively, including variable lease costs of $0.4 million and $0.3 million, respectively, was recorded in operating expenses on the condensed consolidated statements of operations. For the nine months ended September 30, 2020 and 2019, $4.3 million and $3.8 million, respectively, including variable lease costs of $1.1 million and $0.9 million, respectively, was recorded in operating expenses on the condensed consolidated statements of operations. The weighted-average remaining lease term as of September 30, 2020 and December 31, 2019 was 3.4 years and 4.5 years, respectively. The weighted-average discount rate as of September 30, 2020 and December 31, 2019 was 9%. For the three months ended September 30, 2020 and 2019, cash outflows from operating leases, excluding variable lease costs, was $1.1 million and $1.0 million, respectively. For the nine months ended September 30, 2020 and 2019, cash outflows from operating leases, excluding variable lease costs, was $3.2 million and $3.3 million, respectively. Future minimum lease payments at September 30, 2020 are presented in the following table (in thousands). Common area maintenance costs and taxes are not included in these payments. Years ending December 31: Operating Leases (a) 2020 (excluding the nine months ended September 30, 2020) $ 1,625 2021 6,563 2022 5,607 2023 2,545 2024 1,083 Thereafter 1,729 Total future minimum lease payments 19,152 Less: Interest 2,551 Present value of operating lease liabilities $ 16,601 (a) Operating lease payments include $3.9 million related to options to extend lease terms that are reasonably certain of being exercised. In September 2020, we entered into a sublease agreement with Altor Bioscience Manufacturing Company, LLC, a related party (Note 9), whereby we leased approximately 6,901 square feet in El Segundo, California, including laboratory space and related furniture, fixtures and equipment. The agreement also includes certain non-lease components related primarily to the right to use certain common areas within the building and the related furniture and fixtures. This facility will be used to manufacture and produce clinical products for our oncology product candidate trials. The lease runs from August 2020 through July 2022, and includes an option to extend the lease for an additional one year term through July 2023. The monthly fixed charge related to the agreement is $0.2 million, a portion of which will be subject to annual increases of 3% beginning in November 2020 In August 2018, NantBio, Inc., or NantBio, a related party (Note 9), assigned an agreement to us for the use of a third-party research facility, which provides us with the exclusive right to use and access to a portion of the third party’s laboratory and vivarium premises. In conjunction with the assignment, we reimbursed NantBio for upfront payments which it had made to the third party of $0.9 million, and paid $0.5 million directly to the third party for an aggregate value of $1.4 million. The assigned agreement is for a term of ten years In September 2016, we entered into a lease agreement with 605 Doug St, LLC, a related party (Note 9), for approximately 24,250 square feet in El Segundo, California, which has been converted to a research and development laboratory and a current good manufacturing practice, or cGMP, manufacturing facility. The lease runs from July 2016 through July 2023. We have the option to extend the lease for an additional three year July 2017 In March 2016, we entered into a lease agreement for an approximately 7,893 square foot facility in Woburn, Massachusetts, for a research and development laboratory, related office and other related uses. The initial lease term ran for 48 months from April 29, 2016 through May 31, 2020. In June 2016, the lease was amended to add 260 square feet, for a total of 8,153 square feet. Base rent for the initial term of the lease was $19,000 per month with a $1 per square foot annual increase on each anniversary date. In August 2019, we exercised our right pursuant to the lease agreement to extend the term of the lease for an additional two years through May 31, 2022. Consequently, during the third quarter of 2019 we recognized an increase of $0.6 million in both operating lease right-of-use assets and operating lease liabilities on the condensed consolidated balance sheets. Base rent for the extended term of the lease is $25,800 per month with an annual increase of 3% on June 1, 2021. In November 2015, we entered into a facility license agreement with NantWorks LLC, or NantWorks, a related party (Note 9), for approximately 9,500 square feet of office space in Culver City, California, which has been converted to a research and development laboratory and a cGMP manufacturing facility. The initial license was effective in May 2015 and extends through December 2020. Base monthly rent for the initial lease term is $47,000, with annual increases of 3% beginning in January 2017 In June 2015, we entered into a lease agreement for an approximately 44,700 square foot facility in San Diego, California, for a research and development laboratory, related office and other related uses. The term of the lease extends for seven years Commitments We did not enter into any significant contracts during the nine months ended September 30, 2020, other than those disclosed in these unaudited condensed consolidated financial statements.

Related Party Agreements

Related Party Agreements	9 Months Ended
	Sep. 30, 2020
Related Party Transactions [Abstract]
Related Party Agreements	9. Related Party Agreements Our Chairman founded and has a controlling interest in NantWorks, which is a collection of multiple companies in the healthcare and technology space. As described below, we have entered into arrangements with NantWorks, and certain affiliates of NantWorks, to facilitate the development of new genetically modified NK cells for our product pipeline. Affiliates of NantWorks are also affiliates of the company due to the common control by and/or common ownership interest of our Chairman. NantWorks Under the NantWorks shared services agreement executed in November 2015, but effective August 2015, NantWorks provides corporate, general and administrative, manufacturing strategy, research and development, regulatory and clinical trial strategy, and other support services. We are charged for the services at cost plus reasonable allocations for indirect costs that relate to the employees providing the services. For the three months ended September 30, 2020 and 2019, we recorded selling, general and administrative expense under this arrangement of $0.5 million and $0.5 million, respectively. For the nine months ended September 30, 2020 and 2019, we recorded selling, general and administrative expense under this arrangement of $1.8 million and $1.7 million, respectively. For the three months ended September 30, 2020 and 2019, we recorded research and development expense under this arrangement of $0.3 million and $0.4 million, respectively. For the nine months ended September 30, 2020 and 2019, we recorded research and development expense under this arrangement of $1.3 million and $1.0 million, respectively. These amounts exclude certain general and administrative expenses provided by third party vendors directly for our benefit, which have been reimbursed to NantWorks based on those vendors’ invoiced amounts without markup by NantWorks. In June 2016, we amended the existing shared services agreement with NantWorks whereby we can provide support services to NantWorks and/or any of its affiliates. For the three months ended September 30, 2020 and 2019, we recorded selling, general and administrative expense reimbursements of $0.4 million and $0.2 million, respectively. For the nine months ended September 30, 2020 and 2019, we recorded selling, general and administrative expense reimbursements of $1.1 million and $0.6 million, respectively. For the three months ended September 30, 2020 and 2019, we recorded research and development expense reimbursements of $0.4 million and $0.6 million, respectively. For the nine months ended September 30, 2020 and 2019, we recorded research and development expense reimbursements of $1.2 million and $1.7 million, respectively. We owed NantWorks a net amount of $0.7 million and $0.4 million for all agreements between the two affiliates at September 30, 2020 and December 31, 2019, respectively, which is included in due to related parties on the condensed consolidated balance sheets. In November 2015, we entered into a facility license agreement with NantWorks, which became effective May 2015, for approximately 9,500 square feet in Culver City, California, which has been converted to a research and development laboratory and a cGMP manufacturing facility. In September 2020, we amended this agreement to extend the term of this lease through December 31, 2021, as further described in Note 8 – Commitments and Contingencies Immuno-Oncology Clinic, Inc. Beginning in 2017, we entered into multiple agreements with Immuno-Oncology Clinic, Inc., or the Clinic (dba Chan Soon-Shiong Institutes for Medicine, in El Segundo, California), to conduct clinical trials related to certain of our product candidates. The Clinic is a related party as it is owned by one officer of NantKwest and NantWorks manages the administrative operations of the Clinic. Prior to June 30, 2019, one of the company’s officers was an investigator or sub-investigator for all of the company’s trials conducted at the Clinic. In July 2019, we entered into a new agreement with the Clinic (the Clinic Agreement), which became effective on July 1, 2019. The Clinic Agreement, as amended on March 31, 2020, covers clinical trial and research related activities on a non-exclusive basis relating to our existing clinical trials, commenced prior to July 1, 2019, and prospective clinical trials and research projects. The Clinic Agreement also specifies certain services and related costs that are excluded from the Clinic Agreement. Prior to commencing any work under the Clinic Agreement, the parties have agreed to execute written work orders setting forth the terms and conditions related to specific services to be performed, including financial terms. For clinical trials that commenced prior to July 1, 2019, fees incurred for services performed after July 1, 2019 are covered under the Clinic Agreement and applied towards the below-mentioned prepayments. The Clinic Agreement allows for an automatic renewal and additional extensions beyond the initial one year term. In consideration of the services to be performed under the Clinic Agreement, as amended on March 31, 2020, we agreed to make payments of up to $7.5 million to the Clinic, of which $3.75 million and $1.875 million were paid in July 2019 and October 2019, respectively. As amended, a conditional payment of $1.875 million shall be due and payable at such time, if any, that the payments made in July 2019 and October 2019 have been earned by the Clinic through performance of services. On a quarterly basis our prepayment is increased by an interest credit computed in accordance with terms specified in the Clinic Agreement. To the extent any portion of the prepayments remain unearned by the Clinic on the third anniversary of the Clinic Agreement, we may elect at our sole discretion either to (i) not extend the term of the Clinic Agreement and have the Clinic reimburse us for the total amount of any remaining unused portion of the prepayments, or (ii) extend the term of the Clinic Agreement for up to three additional one year periods, at which time the Clinic will reimburse us for the total amount of any remaining unused portion of the prepayments plus interest if reimbursement is not made within 60 days of expiration. The Clinic may terminate this agreement upon each anniversary date upon sixty (60) days prior written notice and reimbursement in full to us of any outstanding unearned balance of the prepayments, provided that any such termination by the Clinic will not apply with respect to any work orders still in effect at the time of such termination. In July 2019, we executed a clinical trial work order under the Clinic Agreement for an open-label, phase I study of PD‑L1.t‑haNK for infusion in subjects with locally advanced or metastatic solid cancers. In July 2020, but effective June 22, 2020, we and ImmunityBio executed a clinical trial work order under our existing master agreement with the Clinic for an open-label, randomized, comparative phase II study of ImmunityBio’s proprietary IL‑15 superagonist (N‑803) and Aldoxorubicin Hydrochloride (Aldoxorubicin) and our PD‑L1.t‑haNK with standard-of-care chemotherapy versus standard-of-care chemotherapy for first and second line treatment of locally or advanced metastatic pancreatic cancer. During the three months ended September 30, 2020 and 2019, $0.1 million and $0.3 million, respectively, has been recognized in research and development expense on the condensed consolidated statements of operations related to clinical trial and research related activities conducted for us by the Clinic. During the nine months ended September 30, 2020 and 2019, $0.3 million and $0.9 million, respectively, has been recognized in research and development expense on the condensed consolidated statements of operations related to clinical trial and research related activities conducted for us by the Clinic. At September 30, 2020 and December 31, 2019, we owed the Clinic $0.2 million and $0.1 million, respectively, for services excluded from the Clinic Agreement, which are included in due to related parties on the condensed consolidated balance sheets. At September 30, 2020 and December 31, 2019, we had prepaid balances related to the Clinic Agreement of $4.8 million and $5.1 million, respectively, which are included in prepaid expenses and other currents assets, and other assets, on the condensed consolidated balance sheets. We anticipate that the remaining prepayment amount as of September 30, 2020 will be utilized in future periods as the Clinic provides additional services pursuant to the Clinic Agreement. ImmunityBio ImmunityBio, Inc., or ImmunityBio, is a related party, as it is an affiliate of NantWorks. On August 21, 2020, we entered into a Collaboration Agreement with ImmunityBio as further described in Note 7 – Collaboration and License Agreements In January 2020, we entered into a Cost Allocation Agreement with ImmunityBio which (together with related work orders) is described further in Note 7 – Collaboration and License Agreements In August 2016, we entered into an exclusive Co‑Development Agreement with Altor as described in Note 7 – Collaboration and License Agreements In June 2015, we entered into a supply agreement with ImmunityBio pursuant to which we have the right to purchase ImmunityBio’s proprietary bioreactors, made according to specifications mutually agreed to with ImmunityBio. We also have the right to purchase reagents and consumables associated with such equipment from ImmunityBio. When an upfront payment is made, it is included in prepaid expenses on the condensed consolidated balance sheets until the product is received. The agreement has an initial term of five years one-year At September 30, 2020 and December 31, 2019, we had $3.2 million and $1.8 million, respectively, in capitalized equipment purchased from ImmunityBio, which is included in property, plant and equipment, net, on the condensed consolidated balance sheets. During the three months ended September 30, 2020 and 2019, we recorded research and development expense associated with reagents and consumables purchased from ImmunityBio of $0.2 million and $12,900, respectively, on the condensed consolidated statements of operations. During the nine months ended September 30, 2020 and 2019, we recorded research and development expense associated with reagents and consumables purchased from ImmunityBio of $0.3 million and $0.1 million, respectively, on the condensed consolidated statements of operations. At September 30, 2020 and December 31, 2019 we had $0.1 million and $0.5 million, respectively, included in prepaid expenses and other current assets on the condensed consolidated balance sheets related to consumables purchased from ImmunityBio. Altor Bioscience Manufacturing Company, LLC Sublease Agreement In September 2020, we entered into a sublease agreement with Altor Bioscience Manufacturing Company, LLC, a related party, whereby we leased approximately 6,901 square feet in El Segundo, California, including laboratory space and related furniture, fixtures and equipment. The agreement also includes certain non-lease components related primarily to the right to use certain common areas within the building and the related furniture and fixtures. This facility will be used to manufacture and produce clinical products for our oncology product candidate trials. The lease runs from August 2020 through July 2022, and includes an option to extend the lease for an additional one year term through July 2023. The monthly fixed charge related to the agreement is $0.2 million, a portion of which will be subject to annual increases of 3% beginning in November 2020. In addition, under the agreement, we are required to pay our share of estimated property taxes and operating expenses, both of which are variable lease expenses. Lease expense for this facility is recorded in research and development expense on the condensed consolidated statements of operations and was $0.4 million during the three months ended September 30, 2020. At September 30, 2020, we owed $0.4 million under this agreement related to fixed and variable lease costs covering the period from August 1, 2020 through September 30, 2020. 605 Doug St. LLC In September 2016, we entered into a lease agreement with 605 Doug St, LLC, an entity owned by our Chairman, for approximately 24,250 square feet in El Segundo, California, which has been converted to a research and development laboratory and a cGMP manufacturing facility. The lease runs from July 2016 through July 2023. We have the option to extend the lease for an additional three-year term through July 2026. The monthly rent is $0.1 million with annual increases of 3% beginning in July 2017 NantBio In March 2016, NantBio and the National Cancer Institute entered into a cooperative research and development agreement. The initial five year agreement covers NantBio and its affiliates, including us. Under the agreement, the parties are collaborating on the preclinical and clinical development of proprietary recombinant natural killer cells and monoclonal antibodies in monotherapy and in combination immunotherapies. We benefited from the preclinical and clinical research conducted during the first four years under this agreement. In each of the contractual years under the agreement we paid $0.6 million to the National Cancer Institute as a prepayment for services under the agreement. We recognize research and development expense related to this agreement ratably over a 12‑month period for each funding year and recorded $0.2 million and $0.5 million of expense associated with the agreement in each of the three and nine months ended September 30, 2020 and 2019, respectively. As of September 30, 2020 and December 31, 2019, we had a balance of $0.3 million and $0.1 million, respectively, included in prepaid expenses and other current assets related to this agreement, on the condensed consolidated balance sheets.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Stockholders' Equity	10. Stockholders’ Equity Equity Offering – On June 29, 2020, the company closed an underwritten public offering of an aggregate of 8,521,500 shares of common stock, which included 4,811,500 shares issued to the public at a price of $9.50 per share (which includes 1,111,500 shares sold to the public upon full exercise of the underwriters’ option to purchase additional shares at a public offering price of $9.50 per share), less underwriting discounts and commissions, and 3,710,000 shares issued to our Chairman and principal stockholder, Dr. Patrick Soon-Shiong, at a price of $12.12 per share, less underwriting discounts and commissions. All of the shares were offered by the company. Including the underwriters’ option exercise, the aggregate gross proceeds from the offering were approximately $90.7 million, before deducting underwriting discounts, commissions and other offering expenses of approximately $4.4 million. Stock Repurchase – In November 2015, the board of directors approved a share repurchase program, or the 2015 Share Repurchase Program, allowing the CEO or CFO, on behalf of the company, to repurchase from time to time, in the open market or in privately negotiated transactions, up to $50.0 million of our outstanding shares of common stock, exclusive of any commissions, markups or expenses. The timing and amounts of any purchases were and will continue to be based on market conditions and other factors, including price, regulatory requirements and other corporate considerations. The 2015 Share Repurchase Program does not require the purchase of any minimum number of shares and may be suspended, modified, or discontinued at any time without prior notice. We have financed, and expect to continue to finance, the purchases with existing cash balances. At September 30, 2020, $18.3 million remained authorized for repurchase under the 2015 Share Repurchase Program. No shares were repurchased during the nine months ended September 30, 2020. During the nine months ended September 30, 2019, we repurchased 473,586 shares of our common stock at prices ranging between $0.95 per share and $1.09 per share for a total cost of $0.5 million. In addition, we paid $14,200 of broker commissions on these repurchases. The shares are formally retired through board approval upon repurchase. In July 2015, the company's board of directors adopted and the company’s stockholders approved the 2015 Equity Incentive Plan, or the 2015 Plan. The 2015 Plan is the only equity plan of the company available for grant of equity awards to employees, directors and consultants of the company. In April 2019, the company’s board of directors adopted, and in June 2019 the company’s stockholders approved, a first amendment to the 2015 Plan to reserve a further 3,000,000 shares of common stock for issuance pursuant to the 2015 Plan. In March 2020, the company’s board of directors adopted, and in June 2020 the company’s stockholders approved, a second amendment to the 2015 Plan to reserve a further 3,000,000 shares of common stock for issuance pursuant to the 2015 Plan. As of September 30, 2020, a total of approximately 10.2 million shares of common stock were reserved for issuance pursuant to the 2015 Plan and a total of approximately 7.2 million shares were available for future grant.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	11. Stock-Based Compensation The following table presents all stock-based compensation as included on the condensed consolidated statements of operations (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 (Unaudited) (Unaudited) Stock-based compensation expense: Employee stock options $ 545 $ 103 $ 842 $ 1,204 Employee RSUs 143 79 516 642 Non-employee RSUs 23 95 114 304 $ 711 $ 277 $ 1,472 $ 2,150 Stock-based compensation expense in operating expenses: Research and development $ 76 $ 98 $ 149 $ 359 Selling, general and administrative 635 179 1,323 1,791 $ 711 $ 277 $ 1,472 $ 2,150 Stock Options The following table summarizes stock option activity under all equity incentive plans for the nine months ended September 30, 2020: Number of Shares Weighted- Average Exercise Price Aggregate Intrinsic Value (in thousands) Weighted- Average Remaining Contractual Life (in years) Outstanding at December 31, 2019 4,506,950 $ 9.37 $ 5,710 5.8 Options granted 400,000 $ 6.21 Options exercised (1,142,273 ) $ 1.88 Options forfeited (116,667 ) $ 3.07 Outstanding at September 30, 2020 3,648,010 $ 11.57 $ 9,374 5.7 Vested and Exercisable at September 30, 2020 2,960,508 $ 13.12 $ 7,973 4.9 Unrecognized compensation cost related to unvested stock options at September 30, 2020 was $1.9 million, which is expected to be recognized over a weighted-average period of 1.1 years. During the three and nine months ended September 30, 2020, we recognized proceeds of $0.4 million and $0.9 million, respectively, from exercises of stock options. The aggregate intrinsic value of stock options exercised during the three and nine months ended September 30, 2020, was $8.7 million and $10.6 million, respectively. During the nine months ended September 30, 2019, we recognized proceeds of $4.1 million from exercises of stock options by our Chairman during March 2019. The company uses a Black-Scholes option-pricing model to determine the fair value of stock-based compensation under U.S. GAAP. The assumptions used for employee stock options granted during the periods presented in these condensed consolidated financial statements are presented in the table below for the nine months ended September 30, 2020 (Unaudited): Expected term (in years) 5.5 Risk-free interest rate 0.4 % Expected volatility 96.8 % Dividend yield 0.0 % Weighted-average grant date fair value $ 4.64 The expected term was estimated using the average of the contractual term and the weighted-average vesting term of the options. The risk-free interest rate assumption was based on the U.S. Treasury’s rates for U.S. Treasury zero-coupon bonds with maturities similar to those of the expected term of the award s being valued. E xpected volatility was estimated based on the historical volatility of our c ommon stock. The assumed dividend yield was based on the company’s expectation of not paying divide nds for the foreseeable future. Restricted Stock Units The following table summarizes the restricted stock units, or RSUs, activity under the 2015 Plan for the nine months ended September 30, 2020: Number of Shares Weighted- Average Grant Date Fair Value Unvested balance at December 31, 2019 1,139,428 $ 2.23 Granted 33,500 $ 6.43 Vested (642,236 ) $ 2.04 Forfeited (50,400 ) $ 4.77 Unvested balance at September 30, 2020 480,292 $ 2.52 As of September 30, 2020, there was $0.8 million of unrecognized stock-based compensation expense related to RSUs that is expected to be recognized over a weighted-average period of 2.0 years. Of that amount, $0.8 million of unrecognized expense is related to employee grants with a remaining weighted-average period of 2.0 years and $14,700 of unrecognized expense is related to non-employee grants with a remaining weighted-average period of 0.5 years. Warrants During the nine months ended September 30, 2019, we recognized proceeds of $35.2 million upon the exercise of warrants by our Chairman during March 2019. As of December 31, 2019 there were no warrants outstanding, and there were no warrants issued during the nine months ended September 30, 2020.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes The difference between the federal statutory tax rate of 21% and our 0% tax rate is due to losses in jurisdictions from which we cannot benefit. Prior to the adoption of ASU 2019‑12 in the first quarter of 2020, as described in Note 2, intraperiod tax allocation rules required us to allocate the provision for income taxes between continuing operations and other categories of earnings, such as other comprehensive income. In periods in which we had a year-to-date pre-tax loss from continuing operations and pre-tax income in other categories of earnings, such as other comprehensive income, we had to allocate the tax provision to the other categories of earnings. We then recorded a related tax benefit in continuing operations. However, with the adoption of ASU 2019‑12, we are no longer required to allocate the tax provision to the other categories of earnings and related benefit to continuing operations under these circumstances. We recorded unrealized gains on marketable debt securities in other comprehensive income during the three and nine months ended September 30, 2019. As a result, we recorded a tax expense of $0 for the three months ended September 30, 2019 and a tax benefit of $34,000 for the nine months ended September 30, 2019 on the condensed consolidated statements of operations. We also recorded a reduction to other comprehensive income of $0 for the three months ended September 30, 2019, and a reduction of $0.1 million for the nine months ended September 30, 2019 on the condensed consolidated balance sheets. We are operating in Korea. During the three and nine months ended September 30, 2020 and 2019, there was no tax expense or benefit related to Korea. We currently file federal and state income tax returns in the U.S. and file Korean statutory tax returns. Income tax expense consists of U.S. federal, state, and Korean income taxes. To date, we have not been required to pay U.S. federal and state income taxes because of current and accumulated net operating losses. On March 27, 2020, the U . S . enacted the Coronavirus Aid, Relief and Economic Security Act , or the C ARES Act. The C ARES Act is an emergency economic stimulus package that includes spending and tax breaks to strengthen the U . S . economy and fund a nationwide effort to curtail the effect of the coronavirus pandemic . While the CARES Act provides sweeping tax changes in response to the pandemic , some of the more significant provisions which are expected to impact our financial statements i nclud e removal of certain limitations on utilization of net operating losses, increasing the loss carryback period for certain losses to five years, and increasing the ability to deduct interest expense, as well as amending certain provisions of the previously enacted Tax Cuts and Jobs Act. Consistent with previous years, we expect to continue to generate net losses in the foreseeable future. We currently have significant federal and state deferred tax assets attributed to prior net operating losses and research and experimentation tax credits. These deferred taxes are fully reserved. As we have never generated taxable income, the CARES Act feature allowing net operating losses originating in 2018, 2019 or 2020 to be carried back five years is not expected to have a significant impact. Management does not expect any other provisions of the CARES Act to have a material impact on our financial position, results of operations or cash flows d uring 2020.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Liquidity	Liquidity On June 29, 2020, the company closed an underwritten public offering of an aggregate of 8,521,500 shares of common stock, which included 4,811,500 shares issued to the public at a price of $9.50 per share (which includes 1,111,500 shares sold to the public upon full exercise of the underwriters’ option to purchase additional shares at a public offering price of $9.50 per share), less underwriting discounts and commissions, and 3,710,000 shares issued to our Chairman and principal stockholder, Dr. Patrick Soon-Shiong, at a price of $12.12 per share, less underwriting discounts and commissions. All of the shares were offered by the company. Including the underwriters’ option exercise, the aggregate gross proceeds from the offering were approximately $90.7 million, before deducting underwriting discounts, commissions and other offering expenses of approximately $4.4 million. As of September 30, 2020, the company had an accumulated deficit of $722.4 million. We also had negative cash flow from operations of $47.4 million during the nine months ended September 30, 2020. The company will likely need additional capital to further fund development of, and seek regulatory approvals for, our product candidates, and to begin to commercialize any approved products. We are currently focused primarily on the development of immunotherapeutic treatments for cancers and debilitating viral infections using targeted cancer and viral killing cell lines, and we believe such activities will result in the company’s continued incurrence of significant research and development and other expenses related to those programs. If the clinical trials for any of the company’s product candidates fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of our product candidates, if approved, fail to achieve market acceptance, we may never become profitable. Even if the company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. We intend to cover our future operating expenses through cash and cash equivalents and marketable debt securities on hand and through a combination of equity offerings, debt financings, government or other third-party funding, marketing and distribution arrangements and other collaborations, strategic alliances, and licensing arrangements. Additional financing may not be available to us when needed and, if available, financing may not be obtained on terms favorable to the company or its stockholders. While we expect our existing cash, and cash equivalents and marketable debt securities will enable us to fund operations and capital expenditure requirements for at least the next 12 months, we anticipate that we will need additional funds to reach commercialization. Failure to obtain adequate financing when needed may require us to delay, reduce, limit, or terminate some or all of our development programs or future commercialization efforts or grant rights to develop and market product candidates that we might otherwise prefer to develop and market ourselves, which could adversely affect our ability to operate as a going concern. If we raise additional funds from the issuance of equity securities, substantial dilution to existing stockholders may result. If we raise additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations , as well as covenants and specific financial ratios that may restrict our ability to operate our business.
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP and pursuant to the rules and regulations of the Securities and Exchange Commission. The unaudited condensed consolidated financial statements reflect all adjustments which are, in the opinion of management, necessary for a fair presentation of our financial position and results of operations. The unaudited condensed consolidated financial statements do not include all information and notes required by U.S. GAAP for annual reports. Accordingly, these financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the fiscal year ended December 31, 2019 included in our Annual Report on Form 10‑K. Interim operating results are not necessarily indicative of operating results for the full year. The condensed consolidated financial statements have been prepared assuming the company will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or amounts and classification of liabilities that may result from the outcome of the uncertainty discussed in the Liquidity section of Note 1. We believe our existing cash, cash equivalents, and investments in marketable debt securities, will be sufficient to fund operations through at least the next 12 months following the issuance date of the financial statements. We may also seek to sell additional equity, through one or more follow-on public offerings, or in separate financings, or obtain a credit facility. However, we may not be able to secure such financing in a timely manner or on favorable terms. Without additional funds, we may choose to delay or reduce our operating or investment expenditures. Further, because of the risk and uncertainties associated with the commercialization of the company’s product candidates in development, we may need additional funds to meet our needs sooner than planned.
Principles of Consolidation and Equity Investments	Principles of Consolidation and Equity Investments The condensed consolidated financial statements include the accounts of NantKwest and its wholly owned subsidiaries. All intercompany amounts have been eliminated. We apply the variable interest model under Accounting Standards Codification, or ASC, Topic 810, Consolidation For entities we hold as an equity investment that are not consolidated under the VIE model, we consider whether our investment constitutes ownership of a majority of the voting interests in the entity and therefore should be considered for consolidation under the voting interest model. Unconsolidated equity investments in the common stock or in-substance common stock of an entity under which we are able to exercise significant influence, but not control, are accounted for using the equity method. Our ability to exercise significant influence is generally indicated by ownership of 20 to 50 percent interest in the voting securities of the entity. All other unconsolidated equity investments on which we are not able to exercise significant influence will be subsequently measured at fair value with unrealized holding gains and losses included in other income, net , on the condensed consolidated statements of operations. In the instance the equity investment does not have a readily determinable fair value and does not qualify for the practical expedient to estimate fair value in accordance with ASC 820, Fair Value Measurement , or ASC 820, we will apply the measurement alternative under ASC 321, Investments—Equity Securities , or ASC 321 , pursuant to which we will measure the investment at its cost less impairment, adjusted for observable price changes in an orderly market for an identical or similar investment of the same issuer. We own non-marketable equity securities that are accounted for using the measurement alternative under ASC 321 because the preferred stock held by us is not considered in-substance common stock and such preferred stock does not have a readily determinable fair value. All investments are reviewed on a regular basis for possible impairment. If an investment's fair value is determined to be less than its net carrying value, the investment is written down to its fair value. Such an evaluation is judgmental and dependent on specific facts and circumstances. Factors considered in determining whether an impairment indicator is present include: the investees’ earnings performance and clinical trial performance, change in the investees’ industry and geographic area in which it operates, offers to purchase or sell the security for a price less than the cost of the investment, issues that raise concerns about the investee's ability to continue as a going concern, and any other information that we may be aware of related to the investment. Factors considered in determining whether an observable price change has occurred include: the price at which the investee issues equity instruments similar to those of our investment and the rights and preferences of those equity instruments compared to ours.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, we evaluate our estimates, including those related to valuation of equity-based awards, deferred income taxes and related valuation allowances, preclinical and clinical trial accruals, impairment assessments, the measurement of right-of-use assets and lease liabilities, useful lives of long-lived assets, loss contingencies, and fair value measurements. We base our estimates on historical experience and on various other market-specific and relevant assumptions that we believe to be reasonable under the circumstances. Estimates are assessed each period and updated to reflect current information, such as the economic considerations related to the impact that the ongoing coronavirus pandemic could have on our significant accounting estimates. Actual results could differ from those estimates.
Risks and Uncertainties	Risks and Uncertainties In March 2020, the World Health Organization declared the novel strain of coronavirus disease (SARS‑CoV‑2) outbreak a pandemic. To date, our operations have not been significantly impacted by the pandemic. However, we cannot at this time predict the specific extent, duration, or full impact that this pandemic may have on our financial condition and results of operations, including ongoing and planned clinical trials. More specifically, the pandemic may result in prolonged impacts that we cannot predict at this time and we expect that such uncertainties will continue to exist until such time a vaccine is broadly available and in use. The impact of the pandemic on the financial performance of the company will depend on future developments, including the duration and spread of the outbreak and related governmental advisories and restrictions. These developments and the impact of the ongoing pandemic on the financial markets and the overall economy are highly uncertain. If the financial markets and/or the overall economy are impacted for an extended period, our results may be adversely affected.
Contingencies	Contingencies We record accruals for loss contingencies to the extent that we conclude it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. We evaluate, on a quarterly basis, developments in legal proceedings and other matters that could cause a change in the potential amount of the liability recorded or of the range of potential losses disclosed. Moreover, we record gain contingencies only when they are realizable, and the amount is known. Additionally, we record our rights to insurance recoveries, limited to the extent of incurred or probable losses, as a receivable when such recoveries have been agreed to with our third-party insurers and when receipt is deemed probable. This includes instances when our third-party insurers have agreed to pay, on our behalf, certain legal defense costs and settlement amounts directly to applicable law firms and a settlement fund.
Concentration of Credit Risk and Other Risks and Uncertainties	Concentration of Credit Risk and Other Risks and Uncertainties Financial instruments that potentially subject us to concentrations of risk consist principally of cash and cash equivalents and marketable debt securities. Our cash and cash equivalents are held by one major financial institution in the U.S. and one in Korea. Product candidates developed by us will require approvals or clearances from the U.S. Food and Drug Administration , or FDA , or international regulatory agencies prior to commercial sales. There can be no assurance that any of our product candidates will receive any of the required approval s or clearance s . If we w ere to be denied approval or clearance or any such approval or clearance w as to be delayed, it would have a material adverse impact on us .
Basic and Diluted Net Loss Per Share of Common Stock	Basic and Diluted Net Loss per Share of Common Stock Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted loss per share is computed similarly to basic loss per share except that the denominator is increased to include the number of additional shares that would have been outstanding if the potential common shares had been issued and if the additional common shares were dilutive. For all periods presented, potentially dilutive securities are excluded from the computation of fully diluted loss per share as their effect is anti-dilutive. The following table details those securities that have been excluded from the computation of potentially dilutive securities: As of September 30, 2020 2019 Outstanding options 3,648,010 4,506,950 Outstanding RSUs 480,292 1,273,278 Total 4,128,302 5,780,228 Amounts in the table above reflect the common stock equivalents of the noted instruments.
Collaboration Arrangements	Collaboration Arrangements We analyze our collaboration arrangements to assess whether they are within the scope of ASC Topic 808, Collaborative Arrangements, Revenue from Contracts with Customers Our collaboration arrangements require us to acquire certain equipment for exclusive use in the joint operating activities. These equipment purchases do not have an alternative use and are therefore expensed as incurred within research and development expenses. Our collaboration arrangements are further discussed within Note 7, Collaboration and License Agreements
Recent Accounting Pronouncements	Recent Accounting Pronouncements Application of New or Revised Accounting Standards – Adopted In November 2018, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2018-18, Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606 Collaboration and License Agreements In December 2019, the FASB issued A SU 2019 ‑ 12, Simplifying the Accounting for Income Taxes , or ASU 2019 ‑12 . The amendments in ASU 2019 ‑ 12 include remov ing the exception to the incremental approach for intraperiod tax allocation when there is a loss from continuing operations and income or a gai n from other items (e.g., discontinued operations or other comprehensive income) , and the exception to the general methodology for calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year . ASU 2019 ‑ 12 also amends other aspects of accounting for income taxes to help simplify and promote consistent application of U.S. GAAP . The guidance is effective for interim and annual periods beginning after December 15, 2020, with early adoption permitted. We early adopted ASU 2019 ‑ 12 effective January 1, 2020, and it did not have a material impact on our consolidated financial statements . Although our adoption of ASU 2019 ‑12 did not have a material impact on our consolidated financial statements during the three and nine months ended September 30, 2020 , it may have a material impact on our consolidated financial statements in future periods due to the removal of the exceptions discussed above. The amendment s related to intraperiod tax allocation were a pplied prospectively, and the amendment related to calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year will be applied prospectively. Application of New or Revised Accounting Standards – Not Yet Adopted In June 2016, the FASB issued ASU 2016‑13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Other recent authoritative guidance issued by the FASB (including technical corrections to the ASC), the American Institute of Certified Public Accountants, and the Securities and Exchange Commission during the three months ended September 30, 2020 did not, or are not expected to, have a material effect on our consolidated financial statements.
Investment in Viracta	Based on the level of equity investment at risk, Viracta is not a VIE and therefore is not consolidated under the VIE model. In addition, we do not hold a controlling financial interest in Viracta and therefore we do not consolidate Viracta under the voting interest model. As the preferred stock is not considered in-substance common stock, the investment is not within the scope of accounting for the investment under the equity method. As the preferred stock does not have a readily determinable fair value and does not qualify for the practical expedient to estimate fair value in accordance with ASC 820, we have elected to apply the measurement alternative under ASC 321, pursuant to which we measure our investment in Viracta at cost, less impairment, adjusted for observable price changes in an orderly market for an identical or similar investment of the same issuer.
Fair Value Measurements	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, based on our principal or, in absence of a principal, most advantageous market for the specific asset or liability. We use a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis, as well as assets and liabilities measured at fair value on a non-recurring basis, in periods subsequent to their initial measurement. The hierarchy requires us to use observable inputs when available, and to minimize the use of unobservable inputs, when determining fair value. The three tiers are defined as follows: • Level 1— Observable inputs that reflect quoted market prices (unadjusted) for identical assets or liabilities in active markets at the measurement date. Since valuations are based on quoted prices that are readily and regularly available in an active market, valuation of these products does not entail a significant degree of judgment. Our Level 1 assets consist of bank deposits and money market funds. • Level 2— Observable inputs other than quoted prices in active markets that are observable either directly or indirectly in the marketplace for identical or similar assets and liabilities. Our Level 2 assets consist of corporate debt securities including commercial paper, government sponsored securities and corporate bonds, as well as foreign municipal securities. • Level 3— Valuations based on inputs that are unobservable and significant to the overall fair value measurement. During the periods presented, no transfers were made into or out of the Level 1, 2 or 3 categories. We will continue to review the fair value inputs on quarterly basis. We utilize a third-party pricing service to assist in obtaining fair value pricing for our investments in marketable debt securities. Inputs are documented in accordance with the fair value disclosure hierarchy.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Securities Excluded from the Computation of Potentially Dilutive Securities	The following table details those securities that have been excluded from the computation of potentially dilutive securities: As of September 30, 2020 2019 Outstanding options 3,648,010 4,506,950 Outstanding RSUs 480,292 1,273,278 Total 4,128,302 5,780,228 Amounts in the table above reflect the common stock equivalents of the noted instruments.

Financial Statement Details (Ta

Financial Statement Details (Tables)	9 Months Ended
	Sep. 30, 2020
Financial Statement Details [Abstract]
Prepaid Expenses and Other Current Assets	As of September 30, 2020 and December 31, 2019, prepaid expenses and other current assets were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Prepaid preclinical and clinical trial services - with related party (Note 9) $ 3,262 $ 1,021 Insurance premium financing asset 2,262 757 Prepaid services 825 440 Prepaid insurance 657 372 Interest receivable - marketable debt securities 510 222 Prepaid rent 422 392 Prepaid supplies - with related party (Note 9) 306 467 Prepaid license fees 216 78 Prepaid equipment maintenance 165 251 Laboratory equipment deposit 162 — Due from related parties 100 47 Insurance claim receivables — 34 Other 90 24 $ 8,977 $ 4,105
Property, Plant and Equipment, Net	As of September 30, 2020 and December 31, 2019, property, plant and equipment, net, was made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Leasehold improvements $ 33,665 $ 33,406 Buildings 22,690 22,690 Equipment 22,738 21,434 Software 1,190 1,195 Furniture & fixtures 415 383 80,698 79,108 Accumulated depreciation (24,834 ) (18,607 ) $ 55,864 $ 60,501
Other Assets	As of September 30, 2020 and December 31, 2019, other assets were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Prepaid preclinical and clinical trial services - with related party (Note 9) $ 1,570 $ 4,075 Restricted cash 179 179 Prepaid software license fees 118 — Security deposit 113 113 Other 49 19 $ 2,029 $ 4,386
Accrued Expenses	As of September 30, 2020 and December 31, 2019, accrued expenses were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Accrued bonus $ 1,838 $ 2,002 Accrued compensation 1,113 1,064 Accrued professional and service fees 829 975 Accrued laboratory equipment, supplies and related services 635 640 Accrued preclinical and clinical trial costs 627 281 Accrued franchise and sales/use taxes 217 200 Accrued construction costs 164 — Other 74 181 $ 5,497 $ 5,343
Other Current Liabilities	As of September 30, 2020 and December 31, 2019, other current liabilities were made up of (in thousands): September 30, 2020 December 31, 2019 (Unaudited) Financing obligation - current portion $ 2,262 $ 757 Other 37 18 $ 2,299 $ 775
Investment Income, Net	Net investment income is as follows for the three and nine months ended September 30, 2020 and 2019 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 (Unaudited) (Unaudited) Interest income $ 449 $ 424 $ 795 $ 1,325 Investment (amortization expense) accretion income, net (381 ) 13 (474 ) 15 Net realized losses on investments (2 ) (4 ) (2 ) (4 ) $ 66 $ 433 $ 319 $ 1,336

Financial Instruments Investm_2

Financial Instruments Investments in Marketable Debt Securities (Tables)	9 Months Ended
	Sep. 30, 2020
Cash Equivalents And Marketable Securities [Abstract]
Schedule of Investments in available-for-sale Debt Securities	At September 30, 2020, our investments in available-for-sale debt securities, excluding $10.6 million of corporate debt securities and commercial paper included in cash and cash equivalents, are detailed below (in thousands): September 30, 2020 (Unaudited) Amortized Cost Unrealized Gains Unrealized Losses Fair Value Current: Corporate debt securities $ 57,367 $ 3 $ (16 ) $ 57,354 Commercial paper 3,998 1 — 3,999 Current portion 61,365 4 (16 ) 61,353 Noncurrent: Corporate debt securities 769 — — 769 Noncurrent portion 769 — — 769 Total $ 62,134 $ 4 $ (16 ) $ 62,122 At December 31, 2019, our investments in available-for-sale debt securities are detailed below (in thousands): December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Current: Corporate debt securities $ 32,382 $ 10 $ (3 ) $ 32,389 Foreign government bonds 1,007 — — 1,007 Government sponsored securities 2,752 — (4 ) 2,748 Current portion 36,141 10 (7 ) 36,144 Noncurrent: Corporate debt securities 1,501 — (4 ) 1,497 Noncurrent portion 1,501 — (4 ) 1,497 Total $ 37,642 $ 10 $ (11 ) $ 37,641
Accumulated Unrealized Losses on Debt Securities Classified as Available-for-Sale in Continuous Loss Position	Accumulated unrealized losses on debt securities classified as available-for-sale that have been in a continuous loss position for less than 12 months and for more than 12 months September 30, 2020 (Unaudited) Less than 12 months More than 12 months Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Corporate debt securities $ 33,238 $ (16 ) $ — $ — Total $ 33,238 $ (16 ) $ — $ — December 31, 2019 Less than 12 months More than 12 months Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Corporate debt securities $ 11,021 $ (3 ) $ 1,497 $ (4 ) Government sponsored securities — — 2,748 (4 ) Total $ 11,021 $ (3 ) $ 4,245 $ (8 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	Financial assets and liabilities measured at fair value on a recurring basis are summarized below at September 30, 2020 and December 31, 2019 (in thousands): Fair Value Measurements at September 30, 2020 (Unaudited) Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents $ 27,688 $ 17,100 $ 10,588 $ — Corporate debt securities 57,354 — 57,354 — Commercial paper 3,999 — 3,999 — Noncurrent: Corporate debt securities 769 — 769 — Total assets measured at fair value $ 89,810 $ 17,100 $ 72,710 $ — Fair Value Measurements at December 31, 2019 Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents $ 15,508 $ 15,508 $ — $ — Corporate debt securities 32,389 — 32,389 — Foreign government bonds 1,007 — 1,007 — Government sponsored securities 2,748 — 2,748 — Noncurrent: Corporate debt securities 1,497 — 1,497 — Total assets measured at fair value $ 53,149 $ 15,508 $ 37,641 $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Summary of Future Minimum Lease Payments	Future minimum lease payments at September 30, 2020 are presented in the following table (in thousands). Common area maintenance costs and taxes are not included in these payments. Years ending December 31: Operating Leases (a) 2020 (excluding the nine months ended September 30, 2020) $ 1,625 2021 6,563 2022 5,607 2023 2,545 2024 1,083 Thereafter 1,729 Total future minimum lease payments 19,152 Less: Interest 2,551 Present value of operating lease liabilities $ 16,601 (a) Operating lease payments include $3.9 million related to options to extend lease terms that are reasonably certain of being exercised.

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation Expenses Included on Operations Statement	The following table presents all stock-based compensation as included on the condensed consolidated statements of operations (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 (Unaudited) (Unaudited) Stock-based compensation expense: Employee stock options $ 545 $ 103 $ 842 $ 1,204 Employee RSUs 143 79 516 642 Non-employee RSUs 23 95 114 304 $ 711 $ 277 $ 1,472 $ 2,150 Stock-based compensation expense in operating expenses: Research and development $ 76 $ 98 $ 149 $ 359 Selling, general and administrative 635 179 1,323 1,791 $ 711 $ 277 $ 1,472 $ 2,150
Summarizes Stock Option Activity Under Equity Intensive Plan	The following table summarizes stock option activity under all equity incentive plans for the nine months ended September 30, 2020: Number of Shares Weighted- Average Exercise Price Aggregate Intrinsic Value (in thousands) Weighted- Average Remaining Contractual Life (in years) Outstanding at December 31, 2019 4,506,950 $ 9.37 $ 5,710 5.8 Options granted 400,000 $ 6.21 Options exercised (1,142,273 ) $ 1.88 Options forfeited (116,667 ) $ 3.07 Outstanding at September 30, 2020 3,648,010 $ 11.57 $ 9,374 5.7 Vested and Exercisable at September 30, 2020 2,960,508 $ 13.12 $ 7,973 4.9
Weighted Average of Fair Value of Options Under Black-Scholes Option-Pricing Model	The company uses a Black-Scholes option-pricing model to determine the fair value of stock-based compensation under U.S. GAAP. The assumptions used for employee stock options granted during the periods presented in these condensed consolidated financial statements are presented in the table below for the nine months ended September 30, 2020 (Unaudited): Expected term (in years) 5.5 Risk-free interest rate 0.4 % Expected volatility 96.8 % Dividend yield 0.0 % Weighted-average grant date fair value $ 4.64
Restricted Stock Units (RSUs) Activity	The following table summarizes the restricted stock units, or RSUs, activity under the 2015 Plan for the nine months ended September 30, 2020: Number of Shares Weighted- Average Grant Date Fair Value Unvested balance at December 31, 2019 1,139,428 $ 2.23 Granted 33,500 $ 6.43 Vested (642,236 ) $ 2.04 Forfeited (50,400 ) $ 4.77 Unvested balance at September 30, 2020 480,292 $ 2.52

Description of Business - Addit

Description of Business - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Jun. 29, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Proceeds from equity offering, net of issuance costs paid		$ 86,302	$ 0
Accumulated deficit		(722,442)		$ (662,191)
Net cash used in operating activities		$ (47,397)	$ (46,477)
Underwritten Public Offering
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Shares issued	8,521,500
Proceeds from equity offering, net of issuance costs paid	$ 90,700
Underwriting discounts, commissions and other offering expenses	$ 4,400
Underwritten Public Offering | Public
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Shares issued	4,811,500
Share price	$ 9.50
Underwritten Public Offering | Shares Sold to Public upon full Exercise of Underwriters Option to Purchase Additional Shares
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Share price	$ 9.50
Shares sold to public upon full exercise of underwriters’ option to purchase additional shares	1,111,500
Underwritten Public Offering | Dr. Patrick Soon-Shiong
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Shares issued	3,710,000
Share price	$ 12.12

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) - VIE	Sep. 30, 2020
Minimum
Accounting Policies [Line Items]
Percentage of ownership interest	20.00%
Maximum
Accounting Policies [Line Items]
Percentage of ownership interest	50.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Securities Excluded from the Computation of Potentially Dilutive Securities (Detail) - shares	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	4,128,302	5,780,228
Employee Stock Option
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	3,648,010	4,506,950
Outstanding RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	480,292	1,273,278

Financial Statement Details - P

Financial Statement Details - Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial Statement Details [Abstract]
Prepaid preclinical and clinical trial services - with related party (Note 9)	$ 3,262	$ 1,021
Insurance premium financing asset	2,262	757
Prepaid services	825	440
Prepaid insurance	657	372
Interest receivable - marketable debt securities	510	222
Prepaid rent	422	392
Prepaid supplies - with related party (Note 9)	306	467
Prepaid license fees	216	78
Prepaid equipment maintenance	165	251
Laboratory equipment deposit	162	0
Due from related parties	100	47
Insurance claim receivables	0	34
Other	90	24
Total prepaid expenses and other current assets	$ 8,977	$ 4,105

Financial Statement Details -_2

Financial Statement Details - Property, Plant and Equipment, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 80,698	$ 79,108
Accumulated depreciation	(24,834)	(18,607)
Property, plant and equipment, net	55,864	60,501
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	33,665	33,406
Buildings
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	22,690	22,690
Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	22,738	21,434
Software
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	1,190	1,195
Furniture And Fixtures
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 415	$ 383

Financial Statement Details - A

Financial Statement Details - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financial Statement Details [Abstract]
Depreciation expense related to property, plant and equipment	$ 2,400,000	$ 2,200,000	$ 6,900,000	$ 6,200,000
Impairment loss on recognized investments	$ 0	$ 0	$ 0	$ 0

Financial Statement Details - O

Financial Statement Details - Other Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial Statement Details [Abstract]
Prepaid preclinical and clinical trial services - with related party (Note 9)	$ 1,570	$ 4,075
Restricted cash	179	179
Prepaid software license fees	118	0
Security deposit	113	113
Other	49	19
Other Assets Noncurrent	$ 2,029	$ 4,386

Financial Statement Details -_3

Financial Statement Details - Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial Statement Details [Abstract]
Accrued bonus	$ 1,838	$ 2,002
Accrued compensation	1,113	1,064
Accrued professional and service fees	829	975
Accrued laboratory equipment, supplies and related services	635	640
Accrued preclinical and clinical trial costs	627	281
Accrued franchise and sales/use taxes	217	200
Accrued construction costs	164	0
Other	74	181
Accrued Liabilities Current	$ 5,497	$ 5,343

Financial Statement Details -_4

Financial Statement Details - Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial Statement Details [Abstract]
Financing obligation - current portion	$ 2,262	$ 757
Other	37	18
Other current liabilities	$ 2,299	$ 775

Financial Statement Details - I

Financial Statement Details - Investment Income, Net (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financial Statement Details [Abstract]
Interest income	$ 449	$ 424	$ 795	$ 1,325
Investment (amortization expense) accretion income, net	(381)	13	(474)	15
Net realized losses on investments	(2)	(4)	(2)	(4)
Investment income, net	$ 66	$ 433	$ 319	$ 1,336

Viracta Investment - Additional

Viracta Investment - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2020	Dec. 31, 2019	May 31, 2019	Jan. 31, 2019	Mar. 31, 2017
Schedule Of Investments [Line Items]
Equity securities			$ 9,253	$ 9,253			$ 8,500
2018 Note and Warrant Purchase Agreement
Schedule Of Investments [Line Items]
Equity securities				$ 9,300
Purchase of convertible note	$ 400	$ 400
Convertible note accrued interest rate	8.00%	8.00%
Debt instrument maturity date	1 year	1 year
2018 Note and Warrant Purchase Agreement | Common Stock
Schedule Of Investments [Line Items]
Warrants exercised to acquire shares					253,120
Series B Preferred Stock | 2018 Note and Warrant Purchase Agreement
Schedule Of Investments [Line Items]
Preferred stock value						$ 800

Financial Instruments Investm_3

Financial Instruments Investments in Marketable Debt Securities - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Investments in available-for-sale debt securities, excluding corporate debt securities and commercial paper included in cash and cash equivalents	$ 61,353	$ 36,144
Available-for-sale, weighted-average remaining contractual life	6 months
Maximum
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale securities, period of unrealized loss positions	12 months	12 months
Minimum
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale securities, period of unrealized loss positions	12 months	12 months
Cash and Cash Equivalents
Schedule Of Available For Sale Securities [Line Items]
Investments in available-for-sale debt securities, excluding corporate debt securities and commercial paper included in cash and cash equivalents	$ 10,600

Financial Instruments Investm_4

Financial Instruments Investments in Marketable Debt Securities - Schedule of Investments in available-for-sale Debt Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	$ 62,134	$ 37,642
Available-for-sale, Unrealized Gains	4	10
Available-for-sale, Unrealized Losses	(16)	(11)
Available-for-sale, Fair Value	62,122	37,641
Current Assets
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	61,365	36,141
Available-for-sale, Unrealized Gains	4	10
Available-for-sale, Unrealized Losses	(16)	(7)
Available-for-sale, Fair Value	61,353	36,144
Current Assets | Government Sponsored Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost		2,752
Available-for-sale, Unrealized Gains		0
Available-for-sale, Unrealized Losses		(4)
Available-for-sale, Fair Value		2,748
Current Assets | Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	57,367	32,382
Available-for-sale, Unrealized Gains	3	10
Available-for-sale, Unrealized Losses	(16)	(3)
Available-for-sale, Fair Value	57,354	32,389
Current Assets | Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	3,998
Available-for-sale, Unrealized Gains	1
Available-for-sale, Unrealized Losses	0
Available-for-sale, Fair Value	3,999
Current Assets | Foreign Government Bonds
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost		1,007
Available-for-sale, Unrealized Gains		0
Available-for-sale, Unrealized Losses		0
Available-for-sale, Fair Value		1,007
Noncurrent Assets
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	769	1,501
Available-for-sale, Unrealized Gains	0	0
Available-for-sale, Unrealized Losses	0	(4)
Available-for-sale, Fair Value	769	1,497
Noncurrent Assets | Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	769	1,501
Available-for-sale, Unrealized Gains	0	0
Available-for-sale, Unrealized Losses	0	(4)
Available-for-sale, Fair Value	$ 769	$ 1,497

Financial Instruments Investm_5

Financial Instruments Investments in Marketable Debt Securities - Accumulated Unrealized Losses on Debt Securities Classified as Available-for-Sale in Continuous Loss Position (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Investments, Less than 12 months, Estimated Fair Value	$ 33,238	$ 11,021
Available-for-Sale Investments, Less than 12 months, Gross Unrealized Losses	(16)	(3)
Available-for-Sale Investments, More than 12 months, Estimated Fair Value	0	4,245
Available-for-Sale Investments, More than 12 months, Gross Unrealized Losses	0	(8)
Government Sponsored Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Investments, Less than 12 months, Estimated Fair Value		0
Available-for-Sale Investments, Less than 12 months, Gross Unrealized Losses		0
Available-for-Sale Investments, More than 12 months, Estimated Fair Value		2,748
Available-for-Sale Investments, More than 12 months, Gross Unrealized Losses		(4)
Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Investments, Less than 12 months, Estimated Fair Value	33,238	11,021
Available-for-Sale Investments, Less than 12 months, Gross Unrealized Losses	(16)	(3)
Available-for-Sale Investments, More than 12 months, Estimated Fair Value	0	1,497
Available-for-Sale Investments, More than 12 months, Gross Unrealized Losses	$ 0	$ (4)

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	$ 89,810	$ 53,149
Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		1,007
Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		2,748
Current Assets | Cash and Cash Equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	27,688	15,508
Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	57,354	32,389
Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	3,999
Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	769	1,497
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	17,100	15,508
Level 1 | Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		0
Level 1 | Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		0
Level 1 | Current Assets | Cash and Cash Equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	17,100	15,508
Level 1 | Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 1 | Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0
Level 1 | Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	72,710	37,641
Level 2 | Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		1,007
Level 2 | Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		2,748
Level 2 | Current Assets | Cash and Cash Equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	10,588	0
Level 2 | Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	57,354	32,389
Level 2 | Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	3,999
Level 2 | Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	769	1,497
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		0
Level 3 | Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		0
Level 3 | Current Assets | Cash and Cash Equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0
Level 3 | Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	$ 0	$ 0

Collaboration and License Agr_2

Collaboration and License Agreements - Additional Information (Detail)	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2015	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)Patient	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)		$ 17,284,000	$ 12,052,000	$ 44,227,000	$ 37,781,000
Due to related parties		1,356,000		1,356,000		$ 486,000
ImmunityBio
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)		200,000	12,900	$ 300,000	100,000
Related party, agreement renewal term	1 year
Altor
Licensing Agreement [Line Items]
Maximum number of patients in phase 1 and 2 for clinical trials | Patient				400
Supplies and milestone charges for conducting clinical trials		0	$ 0	$ 0	$ 0
Joint COVID 19 Collaboration Development Agreement
Licensing Agreement [Line Items]
Term of agreement				5 years
Additional term of agreement renewable upon mutual agreement				5 years
Joint COVID 19 Collaboration Development Agreement | Sales
Licensing Agreement [Line Items]
Profit sharing percentage				60.00%
Joint COVID 19 Collaboration Development Agreement | ImmunityBio
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)		3,500,000		$ 3,500,000
Due to related parties		100,000		100,000
Joint COVID 19 Collaboration Development Agreement | ImmunityBio | Program Equipment Related Costs
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)		3,200,000		3,200,000
Joint COVID 19 Collaboration Development Agreement | ImmunityBio | Other Net Program Related Costs
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)		300,000		$ 300,000
Joint COVID 19 Collaboration Development Agreement | ImmunityBio | Sales
Licensing Agreement [Line Items]
Profit sharing percentage				40.00%
Clinical Trial Cost Allocation Agreement | ImmunityBio
Licensing Agreement [Line Items]
Research and development (including amounts with related parties)		$ 300,000		$ 500,000
Related party, agreement renewal term	1 year

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)

Jan. 01, 2022

Jun. 01, 2021USD ($)

Jan. 01, 2021USD ($)

Aug. 09, 2019USD ($)

Sep. 30, 2020USD ($)ft²

Aug. 31, 2019

Jan. 31, 2019USD ($)

Aug. 31, 2018USD ($)

Sep. 30, 2016USD ($)ft²

Jun. 30, 2016USD ($)ft²$ / ft²

Mar. 31, 2016ft²

Nov. 30, 2015USD ($)ft²

Jun. 30, 2015USD ($)ft²

Sep. 30, 2020USD ($)ft²

Sep. 30, 2019USD ($)

Sep. 30, 2020USD ($)ft²

Sep. 30, 2019USD ($)

Dec. 31, 2018USD ($)

Dec. 31, 2019USD ($)

Commitments And Contingencies [Line Items]

Litigation settlement amount

$ 12,000,000

Attorney's fee to plaintiffs

$ 500,000

Weighted average remaining lease term

3 years 4 months 24 days

3 years 4 months 24 days

3 years 4 months 24 days

4 years 6 months

Weighted average discount rate

9.00%

9.00%

9.00%

9.00%

Cash outflows from operating leases excluding variable lease cost

$ 1,100,000

$ 1,000,000

$ 3,200,000

$ 3,300,000

Right-of-use assets obtained in exchange for operating lease liabilities

$ 5,164,000

800,000

Woburn, Massachusetts

Commitments And Contingencies [Line Items]

Number of square foot of facility leased | ft²

8,153

7,893

Right-of-use assets obtained in exchange for operating lease liabilities

600,000

Base rent - monthly

$ 19,000

Initial term of lease arrangement

48 months

Lease commencement date

Apr. 29, 2016

Addition to number of square foot of facility leased | ft²

260

Annual increase of base rent | $ / ft²

1

Optional extended lease term

2 years

Lease agreement extended lease period

May 31, 2022

Period of agreement

In June 2016, the lease was amended to add 260 square feet, for a total of 8,153 square feet. Base rent for the initial term of the lease was $19,000 per month with a $1 per square foot annual increase on each anniversary date.

Woburn, Massachusetts | Forecast

Commitments And Contingencies [Line Items]

Base rent - monthly

$ 25,800

Percentage of annual increase of base rent

3.00%

Commitment; San Diego

Commitments And Contingencies [Line Items]

Number of square foot of facility leased | ft²

44,700

Base rent - monthly

$ 200,000

Percentage of annual increase of base rent

3.00%

Initial term of lease arrangement

7 years

NantBioScience

Commitments And Contingencies [Line Items]

Reimbursed upfront payment to third-party

$ 900,000

Related party transaction, amount paid to third-party

500,000

Related party transaction, aggregate value

$ 1,400,000

Initial term of agreement entered into with the related party by the entity

10 years

5 years

Related party agreement expiration date

2027-06

Doug St, LLC

Commitments And Contingencies [Line Items]

Period of agreement

The lease runs from July 2016 through July 2023. We have the option to extend the lease for an additional three year term through July 2026. The monthly rent is $0.1 million with annual increases of 3% beginning in July 2017.

Optional extended lease term

3 years

Base rent - monthly

$ 100,000

Percentage of annual increase of base rent

3.00%

Annual percentage increases to base rent commencement date

Jul. 31, 2017

NantWorks

Commitments And Contingencies [Line Items]

Number of square foot of facility leased | ft²

9,500

9,500

9,500

9,500

Base rent - monthly

$ 47,000

Percentage of annual increase of base rent

3.00%

Annual percentage increases to base rent commencement date

Jan. 1, 2021

Jan. 31, 2017

Lease agreement extended lease period

Dec. 31, 2021

Period of agreement

The initial license was effective in May 2015 and extends through December 2020. Base monthly rent for the initial lease term is $47,000, with annual increases of 3% beginning in January 2017

NantWorks | Amendment to Extend Lease Term

Commitments And Contingencies [Line Items]

Right-of-use assets obtained in exchange for operating lease liabilities

$ 1,200,000

NantWorks | Amendment to Extend Lease Term | Forecast

Commitments And Contingencies [Line Items]

Base rent - monthly

$ 54,500

Percentage of annual increase of base rent

3.00%

3.00%

Number of days prior to written notice to terminate lease

30 days

El Segundo California | Altor Bioscience Manufacturing Company, LLC

Commitments And Contingencies [Line Items]

Number of square foot of facility leased | ft²

6,901

6,901

6,901

Period of agreement

0

Optional extended lease term

1 year

Monthly fixed charge

$ 200,000

$ 200,000

Annual percentage increases to monthly fixed charge

3.00%

3.00%

Right-of-use assets obtained in exchange for operating lease liabilities

$ 4,000,000

Annual percentage increases to fixed charge commencement date

Nov. 30, 2020

El Segundo California | Doug St, LLC

Commitments And Contingencies [Line Items]

Number of square foot of facility leased | ft²

24,250

Prepaid Expenses and Other Current Assets

Commitments And Contingencies [Line Items]

Insurance claim receivable

$ 0

$ 0

$ 0

$ 34,000

Directors and Officers Insurance Policy

Commitments And Contingencies [Line Items]

Litigation settlement amount

$ 10,800,000

Selling, General and Administrative

Commitments And Contingencies [Line Items]

Litigation settlement amount

$ 1,200,000

Operating Expenses

Commitments And Contingencies [Line Items]

Operating lease expense

1,700,000

1,300,000

4,300,000

3,800,000

Variable lease costs

$ 400,000

$ 300,000

$ 1,100,000

$ 900,000

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Future Minimum Lease Payments (Detail) $ in Thousands	Sep. 30, 2020USD ($)
Commitments And Contingencies Disclosure [Abstract]
2020 (excluding the nine months ended September 30, 2020)	$ 1,625
2021	6,563
2022	5,607
2023	2,545
2024	1,083
Thereafter	1,729
Total future minimum lease payments	19,152
Less: Interest	2,551
Present value of operating lease liabilities	$ 16,601

Commitments and Contingencies_3

Commitments and Contingencies - Summary of Future Minimum Lease Payments (Parenthetical) (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)
Commitments And Contingencies Disclosure [Abstract]
Operating lease payments related to options to extend lease terms	$ 3.9

Related Party Agreements - Addi

Related Party Agreements - Additional Information (Detail)	1 Months Ended												2 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2020USD ($)ft²Officer	Apr. 30, 2020USD ($)	Oct. 31, 2019USD ($)	Jul. 31, 2019USD ($)	May 31, 2019USD ($)	Aug. 31, 2018USD ($)	Apr. 30, 2017USD ($)	Sep. 30, 2016USD ($)ft²	Apr. 30, 2016USD ($)	Mar. 31, 2016	Nov. 30, 2015USD ($)ft²	Jun. 30, 2015	Sep. 30, 2020USD ($)ft²Officer	Sep. 30, 2020USD ($)ft²Officer	Mar. 31, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)ft²Officer	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Related Party Transaction [Line Items]
Selling, general and administrative expense														$ 4,711,000		$ 4,025,000	$ 16,603,000	$ 13,949,000
Research and development														17,284,000		12,052,000	44,227,000	37,781,000
Due to related parties	$ 1,356,000												$ 1,356,000	1,356,000			1,356,000		$ 486,000
Due from related parties	$ 100,000												$ 100,000	$ 100,000			$ 100,000		47,000
NantWorks
Related Party Transaction [Line Items]
Number of square foot of facility leased | ft²	9,500										9,500		9,500	9,500			9,500
Lease agreement extended lease period	Dec. 31, 2021
Base rent - monthly											$ 47,000
Percentage of annual increase of base rent											3.00%
Annual percentage increases to base rent commencement date	Jan. 1, 2021										Jan. 31, 2017
NantWorks | Research and Development
Related Party Transaction [Line Items]
Lease expense														$ 200,000		100,000	$ 500,000	400,000
NantWorks | Shared Services Agreement
Related Party Transaction [Line Items]
Selling, general and administrative expense														500,000		500,000	1,800,000	1,700,000
Research and development														300,000		400,000	1,300,000	1,000,000
NantWorks | Shared Services Agreement | Reimbursements
Related Party Transaction [Line Items]
Selling, general and administrative expense														400,000		200,000	1,100,000	600,000
Research and development														400,000		600,000	1,200,000	1,700,000
Due to related parties	$ 700,000												$ 700,000	700,000			700,000		400,000
Immuno-Oncology Clinic, Inc. | California
Related Party Transaction [Line Items]
Research and development														100,000		300,000	300,000	900,000
Due to related parties	$ 200,000												$ 200,000	$ 200,000			$ 200,000		100,000
Number of officers | Officer	1												1	1			1
Initial term of agreement				1 year
Related party transaction installment payment			$ 1,875,000	$ 3,750,000
Related party transaction conditional payment	$ 1,875,000												$ 1,875,000	$ 1,875,000			$ 1,875,000
Prepayments remain unearned extension description																	To the extent any portion of the prepayments remain unearned by the Clinic on the third anniversary of the Clinic Agreement, we may elect at our sole discretion either to (i) not extend the term of the Clinic Agreement and have the Clinic reimburse us for the total amount of any remaining unused portion of the prepayments, or (ii) extend the term of the Clinic Agreement for up to three additional one year periods, at which time the Clinic will reimburse us for the total amount of any remaining unused portion of the prepayments plus interest if reimbursement is not made within 60 days of expiration.
Notice period to terminate new agreement																	60 days
Prepaid balance included in prepaid expenses and other current assets and other assets	4,800,000												4,800,000	4,800,000			$ 4,800,000		5,100,000
Immuno-Oncology Clinic, Inc. | California | Maximum
Related Party Transaction [Line Items]
Estimated cost for new agreement with clinic															$ 7,500,000
ImmunityBio
Related Party Transaction [Line Items]
Research and development														200,000		12,900	300,000	100,000
Initial term of agreement entered into with the related party by the entity												5 years
Related party, agreement renewal term												1 year
Related parties, capitalized equipment amount																	3,200,000		1,800,000
Prepaid expenses and other current assets	100,000												100,000	100,000			100,000		500,000
ImmunityBio | Joint COVID 19 Collaboration Development Agreement
Related Party Transaction [Line Items]
Research and development														3,500,000			3,500,000
Due to related parties	100,000												100,000	100,000			100,000
ImmunityBio | Joint COVID 19 Collaboration Development Agreement | Program Equipment Related Costs
Related Party Transaction [Line Items]
Research and development														3,200,000			3,200,000
ImmunityBio | Joint COVID 19 Collaboration Development Agreement | Other Net Program Related Costs
Related Party Transaction [Line Items]
Research and development														300,000			300,000
ImmunityBio | Clinical Trial Cost Allocation Agreement
Related Party Transaction [Line Items]
Research and development														300,000			500,000
Related party, agreement renewal term												1 year
ImmunityBio | Collaborative Arrangement | Prepaid Expenses and Other Current Assets
Related Party Transaction [Line Items]
Due from related parties	$ 0												$ 0	0			0
Altor
Related Party Transaction [Line Items]
Supplies and milestone charges for conducting clinical trials														$ 0		0	$ 0	0
Altor Bioscience Manufacturing Company, LLC | El Segundo California
Related Party Transaction [Line Items]
Number of square foot of facility leased | ft²	6,901												6,901	6,901			6,901
Monthly fixed charge	$ 200,000													$ 200,000
Annual percentage increases to monthly fixed charge	3.00%													3.00%
Fixed and variable lease costs													$ 400,000	$ 400,000			$ 400,000
Altor Bioscience Manufacturing Company, LLC | Research and Development | El Segundo California
Related Party Transaction [Line Items]
Lease expense														400,000			$ 400,000
Doug St, LLC
Related Party Transaction [Line Items]
Period of agreement																	The lease runs from July 2016 through July 2023.
Base rent - monthly								$ 100,000
Percentage of annual increase of base rent								3.00%
Annual percentage increases to base rent commencement date								Jul. 31, 2017
Due between parties	$ 0												$ 0	0			$ 0		0
Doug St, LLC | El Segundo California
Related Party Transaction [Line Items]
Number of square foot of facility leased | ft²								24,250
Doug St, LLC | Research and Development
Related Party Transaction [Line Items]
Lease expense														200,000		700,000	200,000	700,000
NantBioScience
Related Party Transaction [Line Items]
Research and development														$ 200,000		$ 500,000	$ 200,000	$ 500,000
Estimated cost for new agreement with clinic						$ 1,400,000
Initial term of agreement entered into with the related party by the entity						10 years				5 years
Research and development expense, ratable payment period																	12 months
Prepayment for services amount		$ 600,000			$ 600,000	$ 600,000	$ 600,000		$ 600,000
NantBioScience | Prepaid Expenses and Other Current Assets
Related Party Transaction [Line Items]
Research and development																	$ 300,000		$ 100,000

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	Jun. 29, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Nov. 30, 2015
Class Of Stock [Line Items]
Proceeds from equity offering, net of issuance costs paid					$ 86,302,000	$ 0
Total amount authorized for repurchase							$ 50,000,000
Repurchase of common stock, shares					0	473,586
Remaining authorized repurchase amount					$ 18,300,000
Repurchase of common stock excluding commissions, value						$ 500,000
Broker commissions on repurchases						$ 14,200
Employee Stock Option | 2015 Equity Incentive Plan
Class Of Stock [Line Items]
Additional common shares reserved for future issuance		3,000,000	3,000,000
Common stock reserved for issuance					10,200,000
Shares available for future grant					7,200,000
Maximum
Class Of Stock [Line Items]
Repurchase of common stock, price per share				$ 1.09		$ 1.09
Underwritten Public Offering
Class Of Stock [Line Items]
Shares issued	8,521,500
Proceeds from equity offering, net of issuance costs paid	$ 90,700,000
Underwriting discounts, commissions and other offering expenses	$ 4,400,000
Underwritten Public Offering | Public
Class Of Stock [Line Items]
Shares issued	4,811,500
Share price	$ 9.50
Underwritten Public Offering | Shares Sold to Public upon full Exercise of Underwriters Option to Purchase Additional Shares
Class Of Stock [Line Items]
Share price	$ 9.50
Shares sold to public upon full exercise of underwriters’ option to purchase additional shares	1,111,500
Underwritten Public Offering | Dr. Patrick Soon-Shiong
Class Of Stock [Line Items]
Shares issued	3,710,000
Share price	$ 12.12

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Based Compensation Expenses Related to Statement of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 711	$ 277	$ 1,472	$ 2,150
Employee Stock Option
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	545	103	842	1,204
Employee RSUs
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	143	79	516	642
Non-employee RSUs
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	23	95	114	304
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	76	98	149	359
Selling, General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 635	$ 179	$ 1,323	$ 1,791

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock Option Activity (Detail) - Employee Stock Option $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020USD ($)$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares
Number of Shares
Stock Options, Beginning Balance | shares	4,506,950
Stock Options, Options granted | shares	400,000
Stock Options, Options exercised | shares	(1,142,273)
Stock Options,Options forfeited | shares	(116,667)
Stock Options, Ending Balance | shares	3,648,010	4,506,950
Stock Options, Vested and Exercisable | shares	2,960,508
Weighted Average Exercise Price
Weighted Average Exercise Price, Outstanding Beginning balance | $ / shares	$ 9.37
Weighted Average Exercise Price, Options granted | $ / shares	6.21
Weighted Average Exercise Price, Options exercised | $ / shares	1.88
Weighted Average Exercise Price, Options forfeited | $ / shares	3.07
Weighted Average Exercise Price, Outstanding Ending balance | $ / shares	11.57	$ 9.37
Weighted Average Exercise Price, Vested and Exercisable | $ / shares	$ 13.12
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding, Beginning balance | $	$ 5,710
Aggregate Intrinsic Value, Outstanding, Ending balance | $	9,374	$ 5,710
Aggregate Intrinsic Value, Vested and Exercisable | $	$ 7,973
Weighted Average Remaining Contractual Life
Weighted Average Remaining Contractual Life, Outstanding	5 years 8 months 12 days	5 years 9 months 18 days
Weighted Average Remaining Contractual Life, Vested and Exercisable	4 years 10 months 24 days

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from stock options exercised	$ 400,000	$ 917,000	$ 4,070,000
Proceeds from exercises of warrants		0	$ 35,151,000
Number of warrants outstanding				0
Number of warrants issued			0
Chairman
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from stock options exercised			$ 4,100,000
Proceeds from exercises of warrants			$ 35,200,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to unvested stock options	1,900,000	$ 1,900,000
Weighted-average period for recognition		1 year 1 month 6 days
Aggregate intrinsic value of stock option exercised	8,700,000	$ 10,600,000
Outstanding RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period for recognition		2 years
Unrecognized compensation cost related to non-vested stock options	800,000	$ 800,000
Employee Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period for recognition		2 years
Unrecognized compensation cost related to non-vested stock options	800,000	$ 800,000
Non Employee Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period for recognition		6 months
Unrecognized compensation cost related to non-vested stock options	$ 14,700	$ 14,700

Stock-Based Compensation - Blac

Stock-Based Compensation - Black-Scholes Option-Pricing Model to Determine Fair Value of Assumptions Used for Employee Stock Options Granted (Detail) - Employee Stock Option - Employee Stock Option	9 Months Ended
	Sep. 30, 2020$ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 years 6 months
Risk-free interest rate	0.40%
Expected volatility	96.80%
Dividend yield	0.00%
Weighted-average grant date fair value	$ 4.64

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (RSUs) Activity (Detail) - Outstanding RSUs	9 Months Ended
	Sep. 30, 2020$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvested, Beginning balance | shares	1,139,428
Number of Shares, Granted | shares	33,500
Number of Shares, Vested | shares	(642,236)
Number of Shares, Forfeited | shares	(50,400)
Number of Shares, Unvested, Ending balance | shares	480,292
Weighted-Average Grant Date Fair Value, Unvested, beginning balance | $ / shares	$ 2.23
Weighted-Average Grant Date Fair Value, Granted | $ / shares	6.43
Weighted-Average Grant Date Fair Value, Vested | $ / shares	2.04
Weighted-Average Grant Date Fair Value, Forfeited | $ / shares	4.77
Weighted-Average Grant Date Fair Value, Unvested, ending balance | $ / shares	$ 2.52

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax [Line Items]
Federal statutory tax rate			21.00%
Company's effective tax rate			0.00%
Tax expense (benefit)		$ 0		$ (34,000)
Tax benefit in other comprehensive income		0		100,000
Korea
Income Tax [Line Items]
Tax benefit	$ 0	$ 0	$ 0	$ 0