0000950170-21-000946 | 10-Q | XBRL Viewer

Restricted cash - non-current assets

$ 256,146

$ 191,859

^[1]

$ 291,388

$ 188,425

917

^[1]

917

Total

$ 257,063

$ 192,776

$ 292,305

$ 189,342

[1]	The condensed balance sheet as of December 31, 2020 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.

Fair Value Measurements and Investments

6 Months Ended

Jun. 30, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements and Investments

4. Fair Value Measurements and Investments

In accordance with Accounting Standards Codification (“ASC”) 820-10, Fair Value Measurements and Disclosures, the Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:



Level I: Inputs which include quoted prices in active markets for identical assets and liabilities.



Level II: Inputs other than Level I that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.



Level III: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

The carrying amounts of the Company’s financial instruments, including restricted cash, accounts receivable, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities. The Company’s financial instruments consist of Level I assets which consist primarily of highly liquid money market funds, some of which are included in restricted cash; and U.S. government bonds that are included in long-term and short-term investments.

The following tables set forth the fair value of the Company’s investments subject to fair value measurements on a recurring basis and the level of inputs used in such measurements:


		June 30, 2021
	Valuation Hierarchy	Amortized Cost		Allowance for Credit Losses		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Aggregate Fair Value
		(in thousands)
Assets
Money market funds	Level I	$	235,581	$	—	$	—	$	—	$	235,581
Restricted cash (money market funds)	Level I		917		—		—		—		917
U.S. Government bonds - short term	Level I		10,030		—		1		—		10,031
U.S. Government bonds - long term	Level I		99,900		—		14		—		99,914
Total		$	346,428	$	—	$	15	$	—	$	346,443


		December 31, 2020
	Valuation Hierarchy	Amortized Cost		Allowance for Credit Losses		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Aggregate Fair Value
		(in thousands)
Assets
Money market funds	Level I	$	131,121	$	—	$	—	$	—	$	131,121
Restricted cash (money market funds)	Level I		917		—		—		—		917
U.S. Government bonds - short term	Level I		124,254		—		6		—		124,260
Total securities		$	256,292	$	—	$	6	$	—	$	256,298

All long term investments consist of U.S. government bonds with contractual maturities of eighteen months, and no other securities have contractual maturities of greater than twelve months.

Schedule of Investments Subject to Fair Value Measurements on a Recurring Basis

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

+ References + Details

Fair Value Measurements and Investments (Tables)

6 Months Ended

Jun. 30, 2021

Fair Value Disclosures [Abstract]

The following tables set forth the fair value of the Company’s investments subject to fair value measurements on a recurring basis and the level of inputs used in such measurements:


		June 30, 2021
	Valuation Hierarchy	Amortized Cost		Allowance for Credit Losses		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Aggregate Fair Value
		(in thousands)
Assets
Money market funds	Level I	$	235,581	$	—	$	—	$	—	$	235,581
Restricted cash (money market funds)	Level I		917		—		—		—		917
U.S. Government bonds - short term	Level I		10,030		—		1		—		10,031
U.S. Government bonds - long term	Level I		99,900		—		14		—		99,914
Total		$	346,428	$	—	$	15	$	—	$	346,443


		December 31, 2020
	Valuation Hierarchy	Amortized Cost		Allowance for Credit Losses		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Aggregate Fair Value
		(in thousands)
Assets
Money market funds	Level I	$	131,121	$	—	$	—	$	—	$	131,121
Restricted cash (money market funds)	Level I		917		—		—		—		917
U.S. Government bonds - short term	Level I		124,254		—		6		—		124,260
Total securities		$	256,292	$	—	$	6	$	—	$	256,298

Research and Collaboration Agreements - ImmunoGen, Inc - Additional Information (Details)	1 Months Ended	3 Months Ended			6 Months Ended
	Jan. 31, 2014 USD ($) Target	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Feb. 29, 2020 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research And Development Expense		$ 26,100,000	$ 24,066,000		$ 48,472,000	$ 66,880,000
Collaborative Arrangement \| Immuno Gen Inc
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront cash payment	$ 0
Number of research targets selected \| Target	2
Milestone payments payable							$ 3,000,000.0
Research And Development Expense				$ 3,000,000.0

CONDENSED BALANCE SHEETS - USD ($)
$ in Thousands

Jun. 30, 2021

Dec. 31, 2020

Current assets:

Prepaid expenses and other current assets

$ 256,146

$ 191,859

^[1]

Short-term investments

10,031

124,260

^[1]

Accounts receivable

931

798

^[1]

3,897

7,096

^[1]

Total current assets

271,005

324,013

^[1]

Long-term Investments

99,914

Property and equipment, net

6,699

6,950

^[1]

Intangible assets, net

1,094

1,167

^[1]

Goodwill

949

^[1]

Operating lease right-of-use asset

917

^[1]

20,961

22,495

^[1]

Other assets

901

2,172

^[1]

Total assets

402,440

358,663

^[1]

Current liabilities:

Accounts payable

1,755

2,996

^[1]

Accrued liabilities

19,253

23,059

^[1]

Deferred revenue, current portion

72,369

74,869

^[1]

Total current liabilities

93,377

100,924

^[1]

Deferred revenue, net of current portion

158,189

186,261

^[1]

Operating lease liabilities - long term

19,921

21,675

^[1]

Total liabilities

271,487

308,860

^[1]

Commitments and contingencies (Note 11)

Stockholders' equity:

Common stock, $0.00001 par value; 150,000,000 shares authorized and 65,157,003 and 48,251,819 shares issued and outstanding at June 30, 2021 and December 31, 2020, respectively

^[1]

Additional paid-in capital

615,849

499,964

^[1]

Accumulated other comprehensive income (loss)

(47)

^[1]

Accumulated deficit

(484,912)

(450,115)

^[1]

Total stockholders' equity

130,953

49,803

^[1]

Total liabilities and stockholders' equity

402,440

358,663

^[1]

Convertible Preferred Stock

Stockholders' equity:

Convertible preferred stock, $0.00001 par value; 10,000,000 shares authorized and no shares issued and outstanding at June 30, 2021 and December 31, 2020.

[1]	The condensed balance sheet as of December 31, 2020 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.

Research and Collaboration Agreements - Summary of Contract Liabilities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2021 USD ($)
Revenue From Contract With Customer [Abstract]
Balance at Beginning of Period	$ 261,130
Additions	0
Deductions	(30,572)
Balance at End of Period	$ 230,558

Research and Collaboration Agreements - Schedule of Revenue by Collaboration Partners (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	$ 16,288	$ 16,608	$ 32,259	$ 66,201
AbbVie
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	2,078	1,319	3,306	31,415
Amgen
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	1,874	3,678	4,456	5,373
Astellas
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	4,931	4,204	9,688	4,591
Bristol Myers Squibb
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	$ 7,405	$ 7,407	$ 14,809	$ 24,822

Schedule of Cash, Cash Equivalents, and Restricted Cash

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 22
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 32
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 22
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 220
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

Basis of Presentation and Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2021

Accounting Policies [Abstract]

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the condensed balance sheets that sum to the total of the amounts shown in the condensed statements of cash flows.


	June 30, 2021		December 31, 2020		June 30, 2020		December 31, 2019
	(in thousands)
Cash and cash equivalents	$	256,146	$	191,859	$	291,388	$	188,425
Restricted cash - non-current assets		917		917		917		917
Total	$	257,063	$	192,776	$	292,305	$	189,342

STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($)
$ in Thousands

Total

Common Stock

Additional Paid-in Capital

Accumulated Other Comprehensive Income/(Loss)

Accumulated Deficit

Beginning balance at Dec. 31, 2019

$ 51,113

$ 1

$ 468,285

$ 57

$ (417,230)

Beginning balance, shares at Dec. 31, 2019

45,523,088

2,157

395,528

4,013

279

Ending balance at Mar. 31, 2020

12,205

69,767

$ 1

474,455

336

(405,025)

Ending balance, shares at Mar. 31, 2020

45,918,616

Beginning balance at Dec. 31, 2019

51,113

$ 1

468,285

(417,230)

Beginning balance, shares at Dec. 31, 2019

45,523,088

(41)

Ending balance at Jun. 30, 2020

(3,474)

58,829

$ 1

479,516

(420,704)

Ending balance, shares at Jun. 30, 2020

46,190,070

Beginning balance at Mar. 31, 2020

69,767

$ 1

474,455

336

(405,025)

Beginning balance, shares at Mar. 31, 2020

45,918,616

1,179

Issuance of common stock under the ESPP

199,139

369

Issuance of common stock under the ESPP, shares

72,315

3,513

(320)

Ending balance at Jun. 30, 2020

(15,679)

58,829

$ 1

479,516

(420,704)

Ending balance, shares at Jun. 30, 2020

46,190,070

Beginning balance at Dec. 31, 2020

49,803

^[1]

$ 1

499,964

(47)

(450,115)

Beginning balance, shares at Dec. 31, 2020

48,251,819

Issuance of common stock in follow-on offering, net of issuance costs

107,712

Issuance of common stock in follow-on offering, net of issuance costs, shares

16,428,571

1,023

322,507

3,034

Ending balance at Mar. 31, 2021

(15,554)

146,022

$ 1

611,733

(43)

(465,669)

Ending balance, shares at Mar. 31, 2021

65,002,897

Beginning balance at Dec. 31, 2020

$ 49,803

^[1]

$ 1

499,964

(47)

(450,115)

Beginning balance, shares at Dec. 31, 2020

48,251,819

391,478

$ 62

Ending balance at Jun. 30, 2021

(34,797)

130,953

$ 1

615,849

(484,912)

Ending balance, shares at Jun. 30, 2021

65,157,003

Beginning balance at Mar. 31, 2021

146,022

$ 1

611,733

(43)

(465,669)

Beginning balance, shares at Mar. 31, 2021

65,002,897

173

Issuance of common stock under the ESPP

68,971

518

Issuance of common stock under the ESPP, shares

85,135

3,425

Ending balance at Jun. 30, 2021

(19,243)

$ 130,953

$ 1

$ 615,849

$ 15

$ (484,912)

Ending balance, shares at Jun. 30, 2021

65,157,003

[1]	The condensed balance sheet as of December 31, 2020 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.

Common Stock - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended	6 Months Ended
	Feb. 28, 2021	Jan. 31, 2021	Mar. 31, 2021	Jun. 30, 2021
Class Of Stock [Line Items]
Common stock, value of shares issued in connection with agreement				$ 107,712
Underwritten Public Offering
Class Of Stock [Line Items]
Common stock, value of shares issued in connection with agreement		$ 93,600
Underwriters
Class Of Stock [Line Items]
Common stock, value of shares issued in connection with agreement	$ 14,100
Common Stock
Class Of Stock [Line Items]
Issuance of common stock in follow-on offering, net of issuance costs, shares			16,428,571
Common Stock \| Underwritten Public Offering
Class Of Stock [Line Items]
Issuance of common stock in follow-on offering, net of issuance costs, shares		14,285,714
Common stock price, per share		$ 7.00
Underwriting discounts and commissions and offering expenses	$ 900	$ 6,400
Common Stock \| Underwriters
Class Of Stock [Line Items]
Issuance of common stock in follow-on offering, net of issuance costs, shares		2,142,857
Period granted to underwriters to purchase additional shares		30 days

CONDENSED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2021	Dec. 31, 2020
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	65,157,003	48,251,819
Common stock, shares outstanding	65,157,003	48,251,819
Convertible Preferred Stock
Convertible Preferred stock, par value	$ 0.00001	$ 0.00001
Convertible Preferred stock, shares authorized	10,000,000	10,000,000
Convertible Preferred stock, shares issued	0	0
Convertible Preferred stock, shares outstanding	0	0

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2021	Jul. 31, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Trading Symbol	CTMX
Entity Registrant Name	CytomX Therapeutics, Inc.
Entity Central Index Key	0001501989
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity File Number	001-37587
Entity Tax Identification Number	27-3521219
Entity Address, Address Line One	151 Oyster Point Blvd.
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	650
Local Phone Number	515-3185
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, $0.00001 par value per share
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false
Entity Common Stock, Shares Outstanding		65,157,003

License Agreements

6 Months Ended

Jun. 30, 2021

Research And Development [Abstract]

License Agreements

7. License Agreements

UCSB

The Company has an exclusive, worldwide license agreement with UCSB (the “UCSB Agreement”), relating to the use of certain patents and technology relating to its core technology, including its therapeutic antibodies, and to certain patent rights the Company co-owns with UCSB covering Probody antibodies and other pro-proteins.

In February 2020, the Company recorded $0.8 million of sublicense fees triggered by the $10.0 million milestone payment from Bristol Myers Squibb’s dosing of the first patient in the Part 2 cohort expansion portion of its ongoing BMS-986249 clinical study for the CTLA-4 program. In March 2020, the Company incurred additional sublicense fees of $6.0 million related to the $80.0 million upfront fee received pursuant to the Astellas Agreement entered into in March 2020, and $1.4 million related to the $40.0 million milestone payment from AbbVie for satisfying the CD71 dose escalation success criteria under the CD71 Agreement in March 2020.

The Company incurred no sublicense expenses for the three months ended June 30, 2021 and 2020, and $0.9 million and $9.1 million for the six months ended June 30, 2021 and 2020, respectively, under the provisions of the UCSB Agreement. As of June 30, 2021 and December 31, 2020, there was no outstanding sublicense fee payable to UCSB.

Fair Value Measurements and Investments - Schedule of Investments Subject to Fair Value Measurements on a Recurring Basis (Details) - USD ($)
$ in Thousands

Jun. 30, 2021

Dec. 31, 2020

Jun. 30, 2020

Dec. 31, 2019

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]

$ 256,146

$ 191,859

^[1]

$ 291,388

$ 188,425

Level I

Amortized Cost

346,428

256,292

Allowance for Credit Losses

Gross Unrealized Holding Gains

Gross Unrealized Holding Losses

Aggregate Fair Value

346,443

256,298

Level I | Money market funds

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]

Level I | Restricted cash (money market funds)

235,581

131,121

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]

Level I | U.S. Government bonds - Short Term

917

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]

Investments, Amortized Cost

10,030

124,254

Investments, Allowance for Credit Losses

Investments, Gross Unrealized Holding Gains

Investments, Gross Unrealized Holding Losses

Investments, Aggregate Fair Value

10,031

$ 124,260

Level I | U.S. Government bonds - Long Term

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]

Investments, Amortized Cost

99,900

Investments, Allowance for Credit Losses

Investments, Gross Unrealized Holding Gains

Investments, Gross Unrealized Holding Losses

Investments, Aggregate Fair Value

$ 99,914

[1]	The condensed balance sheet as of December 31, 2020 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.

Leases

6 Months Ended

Jun. 30, 2021

Leases [Abstract]

Leases

10. Leases

Operating Lease

On December 10, 2015, the Company entered into a lease (the “2016 Lease”) with HCP Oyster Point III LLC (the “Landlord”) to lease approximately 76,000 rentable square feet of office and laboratory space located in South San Francisco, California for the Company’s new corporate headquarters.

The term of the Lease commenced on October 1, 2016. The 2016 Lease has an initial term of ten years from the commencement date, and the Company has an option to extend the initial term for an additional five years at the then fair rental value as determined pursuant to the 2016 Lease.

The Lease provided for annual base rent of approximately $3.1 million in the first year of the lease term. The annual base rent for the second twelve months was approximately $4.3 million, which increases on an annual basis beginning from the 25th month to approximately $5.5 million for the tenth year of the lease. The Company utilized the full amount of the one-time improvement allowance of $12.6 million, of which $2.3 million is recoverable by the landlord through increased rent which continues through the expiration of the initial lease term.

In addition, the Company obtained a standby letter of credit (the “Letter of Credit”) in an amount of approximately $0.9 million, which may be drawn by the Landlord to be applied for certain purposes upon the Company’s breach of any provisions under the 2016 Lease. The Company has recorded the $0.9 million Letter of Credit as non-current restricted cash on its balance sheet as of June 30, 2021 and December 31, 2020, respectively.

Rent expense is recognized on a straight-line basis over the term of the lease and accordingly the Company records the difference between cash rent payments and the recognition of rent expense against the operating lease ROU asset. Rent expense for each of the three months ended June 30, 2021 and 2020 was $1.3 million. Rent expense for each of the six months ended June 30, 2021 and 2020 was $2.5 million.

Supplemental information related to leases are as follows:


	Three Months Ended				Six Months Ended
	June 30, 2021		June 30, 2020		June 30, 2021		June 30, 2020
	(in thousands)				(in thousands)
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$	1,273	$	1,239	$	2,547	$	2,478


	June 30, 2021			December 31, 2020
	(in thousands)
Supplemental balance sheet information related to leases:
Operating lease right-of-use assets	$	20,961		$	22,495
Current operating lease liabilities		3,402			3,195
Non-current operating lease liabilities		19,921			21,675
Total operating lease liabilities	$	23,323		$	24,870
Weighted-average remaining lease term (in years)
Operating lease		5.25			5.75
Weighted-average discount rate
Operating lease		8.25	%		8.25	%


	June 30, 2021
	(in thousands)
Maturity of operating lease liabilities
2021	$	2,582
2022		5,273
2023		5,420
2024		5,572
2025 and beyond		10,117
Total lease payments		28,964
Less imputed interest		(5,641	)
Present value of lease liabilities	$	23,323

Leases (Tables)

6 Months Ended

Jun. 30, 2021

Leases [Abstract]

Summary of Supplemental Information Related to Leases

Supplemental information related to leases are as follows:


	Three Months Ended				Six Months Ended
	June 30, 2021		June 30, 2020		June 30, 2021		June 30, 2020
	(in thousands)				(in thousands)
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$	1,273	$	1,239	$	2,547	$	2,478


	June 30, 2021			December 31, 2020
	(in thousands)
Supplemental balance sheet information related to leases:
Operating lease right-of-use assets	$	20,961		$	22,495
Current operating lease liabilities		3,402			3,195
Non-current operating lease liabilities		19,921			21,675
Total operating lease liabilities	$	23,323		$	24,870
Weighted-average remaining lease term (in years)
Operating lease		5.25			5.75
Weighted-average discount rate
Operating lease		8.25	%		8.25	%

Schedule of Maturity of Operating Lease Liabilities


	June 30, 2021
	(in thousands)
Maturity of operating lease liabilities
2021	$	2,582
2022		5,273
2023		5,420
2024		5,572
2025 and beyond		10,117
Total lease payments		28,964
Less imputed interest		(5,641	)
Present value of lease liabilities	$	23,323

Basis of Presentation and Summary of Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2021

Accounting Policies [Abstract]

Basis of Presentation

The accompanying interim condensed financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting.

Unaudited Interim Financial Information

The accompanying interim condensed financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented.

The condensed balance sheet data, as of December 31, 2020, was derived from audited financial statements, but does not include all disclosures required by U.S. GAAP. The condensed results of operations for the three and six months ended June 30, 2021 are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period. The accompanying condensed financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 filed with the SEC.

Use of Estimates

The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates.

Cash and Cash Equivalents

The Company considers all highly liquid investments purchased with original maturities of three months or less at the date of purchase to be cash equivalents.

Restricted Cash

Restricted cash represents a standby letter of credit issued pursuant to an office lease entered in December 2015.


	June 30, 2021		December 31, 2020		June 30, 2020		December 31, 2019
	(in thousands)
Cash and cash equivalents	$	256,146	$	191,859	$	291,388	$	188,425
Restricted cash - non-current assets		917		917		917		917
Total	$	257,063	$	192,776	$	292,305	$	189,342

Investments

All investments have been classified as available-for-sale (“AFS”) and are carried at fair value as determined based upon quoted market prices or pricing models for similar securities at period end. Investments that are not required for use in current operations and that mature in more than 12 months are classified as long-term investments in the accompanying condensed balance sheets. The amortized cost of securities is adjusted for amortization of premiums and accretion of discounts to maturity. Dividend and interest income are recognized when earned. Realized gains and losses are included in earnings and are derived using the specific identification method for determining the cost of securities sold.

The Company assesses impairment of its AFS debt securities investments at each reporting period. Unrealized gains resulting from the excess of the fair value over the amortized cost basis of an investment are reported as a component of accumulated other comprehensive income (loss), net of tax. Unrealized losses or impairments resulting from the fair value of the AFS debt security being below the amortized cost basis are evaluated, using the discounted cash flow model, for identification of credit losses and non-credit related losses. Any credit losses are charged to earnings against the allowance for credit losses of the security, limited to the difference between the fair value and the amortized cost basis of the security. Any difference between the fair value of the security and the amortized cost basis, less the allowance for credit losses, are reported in other comprehensive income (loss). Expected cash inflows due to improvements in credit are recognized through a reversal of the allowance for credit losses subject to the total allowance previously recognized.

In the event of impairment of any security, if management (i) has the intent to sell such security or (ii) will more-likely-than-not be required to sell such security before recovery of its amortized cost basis, such AFS debt security’s amortized cost basis will be written down to its fair value through earnings along with any existing allowance for credit losses.

Comprehensive Income (Loss)

Comprehensive income (loss) represents all changes in stockholders’ equity except those resulting from distributions to stockholders. The Company’s non-credit related unrealized gains and losses on investments during the period represents the component of other comprehensive income (loss) that is excluded from the reported net loss.

Revenue Recognition

The Company’s revenues are primarily derived through its license, research, development and commercialization agreements. The terms of these types of agreements may include (i) licenses for the Company’s technology or programs, (ii) research and development services, and (iii) services or obligations in connection with participation in research or steering committees. Payments to the Company under these arrangements typically include one or more of the following: nonrefundable upfront and license fees, research funding, milestone and other contingent payments to the Company for the achievement of defined collaboration objectives and certain preclinical, clinical, regulatory and sales-based events, as well as royalties on sales of any commercialized products.

The Company assesses whether the promises in its arrangements with customers are distinct performance obligations that should be accounted for separately. Judgment is required to determine whether the license to the Company’s intellectual property is distinct from the research and development services or participation on steering committees.

The Company’s collaboration and license agreements may include contingent payments related to specified research, development and regulatory milestones. Such milestone payments are typically payable under the collaborations when the collaboration partner claims or selects a target, or initiates or advances a covered product candidate in preclinical or clinical development, upon submission for marketing approval of a covered product with regulatory authorities, or upon receipt of actual marketing approvals of a covered product or for additional indications. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At each reporting date, the Company re-evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price by using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price in such period of determination.

The Company’s collaboration and license agreements may also include contingent payments related to sales-based milestones. Sales-based milestones are typically payable when annual sales of a covered product reach specified levels. Sales-based milestones are recognized at the later of when the associated performance obligation has been satisfied or when the sales occur. Unlike other contingency payments, such as regulatory milestones, sales-based milestones are not included in the transaction price based on estimates at the inception of the contract; instead, they are included when the sales or usage occur.

The transaction price in each arrangement is allocated to the identified performance obligations based on the relative standalone selling price (“SSP”) of each distinct performance obligation, which requires judgment. In instances where SSP is not directly observable, such as when a license or service is not sold separately, SSP is determined using information that may include market conditions and other observable inputs. Due to the early stage of the Company’s licensed technology, the license of such technology is typically combined with research and development services and steering committee participation as one performance obligation. In the event that the Company receives non-cash consideration such as consideration in the form of a research license and research support services from the counterparty, the transaction price of a non-monetary exchange that has commercial substance is estimated based on the fair value of the non-cash consideration received, which may be determined through a valuation analysis.

In certain cases, the Company’s performance creates an asset that does not have an alternative use to the customer and the Company has an enforceable right to payment at all times for performance completed to date. In these cases, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition.

AbbVie Ireland Unlimited Company (“AbbVie”), one of the Company’s collaboration partners, entered into a license agreement with Seagen Inc, formerly Seattle Genetics, Inc. (“SGEN”) to license certain intellectual property rights. As part of the Company’s collaboration agreement with AbbVie, the Company is required to pay SGEN sublicense fees for certain milestone achievements and an annual maintenance fee. These sublicense fees are treated as reductions to the transaction price and combined with the performance obligation to which they relate.

Contract Balances

Customer payments are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until the Company satisfies its performance obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional.

Research and Development Expenses

The Company records accrued liabilities for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical and clinical studies, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced, and includes these costs in accrued liabilities in the balance sheets and within research and development expense in the statements of operations. These costs are a significant component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers under the service agreements. The Company makes significant judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations.

Research and development expenses include costs directly attributable to the conduct of research and development programs, including the cost of salaries, payroll taxes, employee benefits, materials, supplies, depreciation on and maintenance of research equipment, the cost of services provided by outside contractors, and the allocated portions of facility costs, such as rent, utilities, insurance, repairs and maintenance, depreciation, and general support services. All costs associated with research and development are expensed as incurred.

Stock-based Compensation

The Company recognizes compensation costs related to stock options granted to employees based on the estimated fair value of the awards on the date of grant. The Company records forfeitures as they are incurred. The Company estimates the grant date fair value, and the resulting stock-based compensation expense, using the Black-Scholes option-pricing model. The grant date fair value of stock-based awards is expensed on a straight-line basis over the period during which the employee is required to provide service in exchange for the award (generally the vesting period).

The Company estimates the fair value of its stock-based awards using the Black-Scholes option-pricing model, which requires the input of assumptions. The assumptions are as follows:



Expected term. The expected term of stock options represents the period that the stock options are expected to remain outstanding and is based on vesting terms, exercise term and contractual lives of the options. The expected term of the ESPP shares is equal to the six-month look-back period.



Expected volatility. The expected stock price volatility for the Company’s stock options is based on the historical stock price volatility over the period which is commensurate with the estimated expected term of the stock awards. Volatility for ESPP shares is equal to the Company’s historical volatility over a six-month offering period.



Risk-free interest rate. The risk-free interest rate is based on the U.S. Treasury yield with a maturity equal to the expected term of the stock options in effect at the time of grant.



Dividend yield. The expected dividend is assumed to be zero as the Company has never paid dividends and has no current plan to pay any dividends on its common stock.

Leases

The Company determines if an arrangement is or contains a lease at inception. Operating leases are recorded as operating lease right-of-use (“ROU”) assets and operating lease liabilities in the Company’s balance sheet. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company uses an implicit rate when readily available, or its incremental borrowing rate based on the information available at lease commencement date in determining the present value of lease payments. The operating lease ROU assets also include any lease prepayments made and reduced by lease incentives. The Company’s lease terms may include options to extend the lease when it is reasonably certain that such option will be exercised. Lease expenses are recognized on a straight-line basis over the lease term. The Company elected the short-term lease recognition exemption. The Company’s operating lease arrangement includes lease and non-lease components which are generally accounted for separately.

Adopted Accounting Pronouncements

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. The amendments in this ASU simplify the accounting for income taxes by removing certain exceptions to the general principles of ASC 740 in order to reduce cost and complexity of its application. The ASU removes the exception related to the incremental approach for intra-period tax allocation as well as two exceptions related to accounting for outside basis differences of equity method investments and foreign subsidiaries. The ASU also amends the scope of ASC 740 related to a franchise tax (or similar tax) that is partially based on income; clarifies when a step-up in the tax basis of goodwill should be considered part of the business combination in which the book goodwill was originally recognized and when it should be considered a separate transaction; specifies that an entity is not required to allocate income tax expense to a legal entity that is both not subject to tax and disregarded by the taxing authority; and clarifies that all tax effects, both deferred and current, should be accounted for in the interim period that includes the enactment date. The Company adopted this ASU on January 1, 2021, and there was no material impact on the financial statements upon adoption of this ASU.

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of Activities Under Company's Stock Option Plans

Activities under the Company’s stock option plans for the six months ended June 30, 2021 were as follows:


	Options Outstanding
	Number of Options			Weighted- Average Exercise Price Per Share
Balances at December 31, 2020		10,929,530		$	10.77
Options granted		3,633,597			7.80
Options exercised		(391,478	)		3.06
Option forfeited/expired		(2,155,707	)		11.20
Balances at June 30, 2021		12,015,942		$	10.05
Options exercisable at June 30, 2021		5,735,023		$	11.92

Total Stock-based Compensation Recognized

Total stock-based compensation recorded related to options granted to employees and non-employees and employee stock purchase plan was as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2021		2020		2021		2020
	(in thousands)
Stock-based compensation expense:
Research and development	$	1,548	$	1,663	$	2,885	$	3,582
General and administrative		1,877		1,850		3,574		3,944
Total stock-based compensation expense	$	3,425	$	3,513	$	6,459	$	7,526

CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Revenues	$ 16,288	$ 16,608	$ 32,259	$ 66,201
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 26,100	$ 24,066	$ 48,472	$ 66,880
General and administrative	9,393	8,680	18,619	18,252
Total operating expenses	35,493	32,746	67,091	85,132
Loss from operations	(19,205)	(16,138)	(34,832)	(18,931)
Interest income	44	454	112	1,530
Other income (expense), net	(82)	5	(77)	16
Loss before income taxes	(19,243)	(15,679)	(34,797)	(17,385)
Benefit from income taxes				(13,911)
Net loss	$ (19,243)	$ (15,679)	$ (34,797)	$ (3,474)
Net loss per share, basic and diluted	$ (0.30)	$ (0.34)	$ (0.55)	$ (0.08)
Shares used to compute net loss per share, basic and diluted	65,055,998	46,057,063	63,023,349	45,890,510
Other comprehensive income (loss):
Unrealized gain (loss) on investments, net of tax	$ 58	$ (320)	$ 62	$ (41)
Comprehensive loss	$ (19,185)	$ (15,999)	$ (34,735)	$ (3,515)

Description of the Business

6 Months Ended

Jun. 30, 2021

Disclosure Text Block [Abstract]

Description of the Business

1. Description of the Business

CytomX Therapeutics, Inc. (the “Company”) is a clinical-stage, oncology-focused biopharmaceutical company with a vision of transforming lives with safer, more effective therapies. The Company aims to build a commercial enterprise to maximize its impact on the treatment of cancer. The Company is advancing potential first-in-class and best-in-class antibody-based therapeutics created using its Probody® therapeutic technology platform that could meaningfully improve outcomes for cancer patients. Its proprietary and unique Probody technology platform is designed to enable “conditional activation” of antibody-based drugs in the tumor microenvironment while minimizing drug activity in healthy tissues and in circulation. The Company is located in South San Francisco, California and was incorporated in the state of Delaware in September 2010.

Commitments and Contingencies - Additional Information (Details) - Patent Infringement Lawsuit - USD ($)		6 Months Ended
	Mar. 04, 2020	Jun. 30, 2021
Loss Contingencies [Line Items]
Lawsuit filed date	March 4, 2020
Name of plaintiff		Vytacera Bio, LLC
Loss contingency, answer, affirmative defenses and counterclaims filing date	May 26, 2020
Loss contingency, answer and counterclaims by plaintiff filing date	Jun. 05, 2020
Loss contingency claim amount		$ 0

License Agreements - Additional Information (Details) - USD ($)

1 Months Ended

3 Months Ended

6 Months Ended

Mar. 23, 2020

Mar. 31, 2020

Feb. 29, 2020

May 31, 2018

Jul. 31, 2017

Apr. 30, 2016

Jun. 30, 2021

Jun. 30, 2020

Jun. 30, 2021

Jun. 30, 2020

Dec. 31, 2020

Accrued Liabilities

$ 19,253,000

$ 23,059,000

^[1]

UCSB

Bristol Myers Squibb Company | Collaboration and License Agreement

Sublicense fees

$ 0

900,000

$ 9,100,000

Accrued Liabilities

$ 0

Milestone payment receivable

Sublicense fees

$ 800,000

$ 10,000,000.0

Astellas Pharma Inc. | Collaboration and License Agreement

Additional sublicense fees

$ 6,000,000.0

Upfront payment received

$ 80,000,000.0

80,000,000.0

AbbVie Ireland Unlimited Company | CD71 Agreement

Additional sublicense fees

1,400,000

Upfront payment received

$ 20,000,000.0

Milestone payment received

$ 40,000,000.0

$ 21,000,000.0

$ 14,000,000.0

[1]	The condensed balance sheet as of December 31, 2020 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.

Research and Collaboration Agreements

6 Months Ended

Jun. 30, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Research and Collaboration Agreements

6. Research and Collaboration Agreements

The following table summarizes the revenue by collaboration partners:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2021		2020		2021		2020
	(in thousands)				(in thousands)
AbbVie	$	2,078	$	1,319	$	3,306	$	31,415
Amgen		1,874		3,678		4,456		5,373
Astellas		4,931		4,204		9,688		4,591
Bristol Myers Squibb		7,405		7,407		14,809		24,822
Total Revenue	$	16,288	$	16,608	$	32,259	$	66,201

AbbVie Ireland Unlimited Company

In April 2016, the Company and AbbVie entered into two agreements, a CD71 Co-Development and Licensing Agreement (the “CD71 Agreement”) and a Discovery Collaboration and Licensing Agreement (as amended and restated in June 2019, the “Discovery Agreement” and together with the CD71 Agreement the “AbbVie Agreements”). Under the terms of the CD71 Agreement, the Company and AbbVie will co-develop a conditionally activated antibody-drug conjugate (“ADC") against CD71, with the Company responsible for preclinical and early clinical development. AbbVie will be responsible for later development and commercialization, with global late-stage development costs shared between the two companies. The Company will assume 35% of the net profits or net losses related to later development and commercialization unless it opts-out. If the Company opts-out from participation of co-development of the CD71 conditionally activated ADC, which includes CX-2029, AbbVie will have sole right and responsibility for the further development, manufacturing and commercialization of such CD71 conditionally activated ADC.

Under the CD71 Agreement, the Company received an upfront payment of $20.0 million in April 2016, and was eligible to initially receive up to $470.0 million in development, regulatory and commercial milestone payments, a 35% profit split on U.S. sales, and royalties on

ex-U.S. sales at percentages in the high teens to low twenties if the Company participates in the co-development of the CD71 conditionally activated ADC subject to a reversion to a royalty on U.S. sales, and reduction in royalties on ex-U.S. sales, if the Company opts-out from the co-development of the CD71 conditionally activated ADC. The Company’s share of later stage co-development costs for each CD71 conditionally activated ADC is capped, provided that AbbVie may offset the Company’s co-development cost above the capped amounts from future payments such as milestone payments and royalties. In July 2017, the Company received a milestone payment of $14.0 million (net of payment of an associated sublicense fee of $1.0 million to SGEN under the Seattle Genetics Agreement) from AbbVie for achieving certain milestones required to be met to begin GLP toxicology studies under the CD71 Agreement. In May 2018, the United States Food and Drug Administration (“FDA”) cleared the IND application for CX-2029. As a result, the Company achieved the IND success criteria under the CD71 Agreement and received a $21.0 million milestone payment (net of the payment of an associated sublicense fee of $4.0 million to SGEN). In March 2020, the Company earned a $40.0 million milestone payment for satisfying the CD71 dose escalation success criteria under the CD71 Agreement.

Under the terms of the Discovery Agreement, AbbVie receives exclusive worldwide rights to develop and commercialize conditionally activated ADCs against up to two targets, one of which was selected in March 2017. The Company shall perform research services to discover the Probody therapeutics and create conditionally activated ADCs for the nominated collaboration targets. From that point, AbbVie shall have sole right and responsibility for development and commercialization of products comprising or containing such conditionally activated ADCs (“Discovery Licensed Products”).

Under the Discovery Agreement, the Company received an upfront payment of $10.0 million in April 2016 and subsequently earned an additional $10.0 million milestone payment triggered by selection of the second target by AbbVie in June 2019. The Company is also eligible to receive up to $265.0 million for each target, in development, regulatory and commercial milestone payments and royalties at percentages in the high single to low teens from commercial sales of any resulting conditionally activated ADCs. The second target was selected under the Discovery Agreement that allows AbbVie to select a target for developing a conditionally activated ADC or a Probody.

The $40.0 million milestone payment earned in March 2020 for satisfying the CD71 dose escalation success criteria under the CD71 Agreement was included as part of the transaction price as it was unconstrained during the first quarter of 2020 and $26.6 million was recognized as revenue related to this milestone reflecting the percentage completed to-date on the project as of March 2020. The remainder is being recognized as revenues over the remaining estimated research service period through March 2023.

The Company determined that the remaining potential milestone payments of both agreements, if recognized, are probable of significant revenue reversal as their achievement is highly dependent on factors outside the Company’s control. Therefore, these payments continue to be fully constrained and are not included in the transaction price as of June 30, 2021.

The Company recognized revenue of $2.1 million and $1.3 million for the three months ended June 30, 2021 and 2020, respectively, and $3.3 million and $31.4 million for the six months ended June 30, 2021 and 2020, respectively, related to the AbbVie Agreements. As of June 30, 2021 and December 31, 2020, deferred revenue related to the CD71 Agreement performance obligation was $23.3 million and $25.2 million, respectively, and deferred revenue related to the Discovery Agreement performance obligation was $6.6 million and $8.0 million, respectively. No amounts were due from AbbVie as of both June 30, 2021 and December 31, 2020.

Amgen, Inc.

On September 29, 2017, the Company and Amgen, Inc. (“Amgen”) entered into a Collaboration and License Agreement (the “Amgen Agreement”). Pursuant to the Amgen Agreement, the Company received an upfront payment of $40.0 million in October 2017. Concurrent with the entry into the Amgen Agreement, the Company and Amgen entered into a Share Purchase Agreement (the “Purchase Agreement”) pursuant to which Amgen purchased 1,156,069 shares of the Company’s common stock at a price of $17.30 per share (calculated based on a 20-day volume-weighted average price), for total proceeds of $20.0 million, which the Company received on October 6, 2017, the closing date of the transaction. The Company estimated a premium on the stock sold to Amgen of $0.5 million, which takes into account a discount due to the lack of marketability resulting from the six-month lockup period.

Under the terms of the Amgen Agreement, the Company and Amgen will co-develop a conditionally activated T-cell engaging bispecific therapeutic targeting epidermal growth factor receptor (the “EGFR Products”). The Company is responsible for early-stage development of EGFR Products and all related costs up to certain pre-set costs and certain limits based on clinical trial size. Amgen will be responsible for late-stage development, commercialization, and all related costs of EGFR Products. Following early-stage development, the Company will have the right to elect to participate financially in the global co-development of EGFR Products with Amgen, during which the Company would bear certain of the worldwide development costs for EGFR Products and Amgen would bear the rest of such costs (the “EGFR Co-Development Option”). If the Company exercises its EGFR Co-Development Option, the Company will share in somewhat less than 50% of the profit and losses from sales of such EGFR Products in the U.S., subject to certain caps, offsets, and deferrals. If the Company chooses not to exercise its EGFR Co-Development Option, the Company will not bear any costs of later stage development. The Company is eligible to

receive up to $455.0 million in development, regulatory, and commercial milestone payments for EGFR Products, and royalties in the low-double-digit to mid-teen percentage of worldwide commercial sales, provided that if the Company exercises its EGFR Co-Development option, it shall receive a profit and loss split of sales in the United States and royalties in the low-double-digit to mid-teen percentage of commercial sales outside of the United States.

Amgen also has the right to select a total of up to three targets, including the two additional targets discussed below. The Company and Amgen collaborate in the research and development of conditionally activated T-cell engaging bispecifics products directed against such targets. Amgen has selected one such target (the “Amgen Other Product”). If Amgen exercises its option within a specified period of time, it can select two such additional targets (the “Amgen Option Products” and, together with the Amgen Other Product, the “Amgen Products”). Except with respect to preclinical activities to be conducted by CytomX, Amgen will be responsible, at its expense, for the development, manufacture, and commercialization of all Amgen Products. If Amgen exercises all of its options and advances all three of the Amgen Products, CytomX was initially eligible to receive up to $950.0 million in upfront, development, regulatory, and commercial milestones and tiered high single-digit to low-teen percentage royalties. The Company concluded that, at the inception of the agreement, Amgen’s option to select the two additional targets is not a material right and does not represent a performance obligation of the agreement.

At the initiation of the collaboration, CytomX had the option to select, from programs specified in the Amgen Agreement, an existing preclinical stage T-cell engaging bispecific product from the Amgen preclinical pipeline. In March 2018, CytomX selected the program. CytomX is responsible, at its expense, for converting this program to a conditionally activated T-cell engaging bispecific product, and thereafter, will be responsible for development, manufacturing, and commercialization of the product (“CytomX Product”). Amgen is eligible to receive up to $203.0 million in development, regulatory, and commercial milestone payments for the CytomX Product, and tiered mid-single digit to low double-digit percentage royalties.

The Company recognized revenue of $1.9 million and $3.7 million for the three months ended June 30, 2021 and 2020, respectively, and $4.5 million and $5.4 million for the six months ended June 30, 2021 and 2020, respectively, related to the Amgen Agreement. As of June 30, 2021 and December 31, 2020, deferred revenue related to the EGFR Products performance obligation was $25.7 million and $29.8 million, respectively. As of June 30, 2021 and December 31, 2020, deferred revenue related to the Amgen Other Products performance obligation was $1.8 million and $2.2 million, respectively. No amounts were due from Amgen as of both June 30, 2021 and December 31, 2020.

Astellas Pharma Inc.

The Company and Astellas Pharma, Inc. (“Astellas”) entered into a Collaboration and License Agreement (the “Astellas Agreement”) on March 23, 2020, the effective date, to collaborate on preclinical research activities to discover and develop certain antibody compounds for the treatment of cancer using the Company’s Probody therapeutic technology.

Under the terms of the Astellas Agreement, the Company granted Astellas an exclusive worldwide right to develop and commercialize Probody therapeutics for up to four collaboration targets, including one initial target and three additional targets (“Additional Targets”). In addition, Astellas has the right to expand the number of Additional Targets from three up to five (the “Expansion Option”) before the third anniversary of the effective date. Furthermore, for a specified number of targets, at a pre-specified time prior to the initiation of the first pivotal study of a product against such target, the Company may elect to participate in certain development costs and share in the profits generated in the United States with respect to such product (“Cost Share Option”). The Cost Share Option, if exercised, will also provide the option for the Company to co-commercialize such product in the United States. The Company does not consider the Cost Share Option as a performance obligation at the inception of the agreement as the participation is at the Company’s discretion.

Pursuant to the Astellas Agreement, the consideration from Astellas is comprised of an upfront fee of $80.0 million and contingent payments for development, regulatory and sales milestones of up to an aggregate of approximately $1.6 billion. If Astellas exercises its Expansion Option for the two Additional Targets, the Company would be eligible to receive additional upfront and milestone payments aggregating to approximately $0.9 billion. The Company is also entitled to tiered royalties from high-single digit to mid-teen percentage royalties from potential future sales. Astellas is responsible for all preclinical research costs incurred by either party as set forth in the preclinical research plan and the Company will receive research and development service fees based on a prescribed FTE rate.

The Company recognized revenue of $4.9 million and $4.2 million for the three months ended June 30, 2021 and 2020, respectively; and $9.7 million and $4.6 million for the six months ended June 30, 2021 and 2020, respectively. Those revenues also included the research and development service revenue of $0.9 million and $0.2 million for the three months ended June 30, 2021 and 2020, respectively, and $1.7 million and $0.2 million for the six months ended June 30, 2021 and 2020, respectively. As of June 30, 2021 and December 31, 2020, deferred revenue relating to the Astellas Agreement was $59.6 million and $67.6 million, respectively. The amount due from Astellas under the Astellas Agreement was $0.9 million and $0.8 million as of June 30, 2021 and December 31, 2020, respectively.

Bristol Myers Squibb Company

On May 23, 2014, the Company and Bristol Myers Squibb Company (“Bristol Myers Squibb”) entered into a Collaboration and License Agreement (the “BMS Agreement”) to discover and develop compounds for use in human therapeutics aimed at multiple immuno-oncology targets using the Company’s Probody therapeutic technology. The effective date of the BMS Agreement was July 7, 2014.

Under the terms of the BMS Agreement, the Company granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize Probody therapeutics for up to four oncology targets. Bristol Myers Squibb had additional rights to substitute up to two collaboration targets within three years of the effective date of the BMS Agreement. These rights expired in May 2017. Each collaboration target had a two-year research term and the two additional targets had to be nominated by Bristol Myers Squibb within five years of the effective date of the BMS Agreement. The research term for each collaboration target could be extended in one year increments up to three times.

Pursuant to the BMS Agreement, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $50.0 million, and the Company was initially entitled to receive contingent payments of up to $25.0 million for additional targets and up to an aggregate of $1,192.0 million for development, regulatory and sales milestones. In addition, the Company was entitled to royalty payments in the mid-single digits to low double-digit percentages from potential future sales. The Company also received research and development service fees based on a prescribed FTE rate that was capped.

On March 17, 2017, the Company and Bristol Myers Squibb entered into Amendment Number 1 to Extend Collaboration and License Agreement (“Amendment 1”). Amendment 1 granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize Probody therapeutics for up to eight additional targets. The effective date of Amendment 1 was April 25, 2017 (“Amendment Effective Date”). Under the terms of Amendment 1, the Company continued to have obligations to Bristol Myers Squibb to discover and conduct preclinical development of Probody therapeutics against any targets they chose to select during the research period under the terms of Amendment 1.

Pursuant to Amendment 1, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $200.0 million and the Company was initially eligible to receive contingent payments for development, regulatory and sales milestones of up to an aggregate of $3,586.0 million for the eight targets. The Company was also entitled to tiered mid-single to low double-digit percentage royalties from potential future sales. Amendment 1 did not change the term of the Bristol Myers Squibb’s royalty obligation under the BMS Agreement. Bristol Myers Squibb’s royalty obligation continues on a licensed-product by licensed-product basis until the later of (i) the expiration of the last claim of the licensed patents covering the licensed products in the country, (ii) the twelfth anniversary of the first commercial sale of a licensed product in a country, or (iii) the expiration of any applicable regulatory, pediatric, orphan drug or data exclusivity with respect to such product.

The initial transaction price for the BMS Agreement and Amendment 1, collectively, was $272.8 million consisting of the upfront fees of $250.0 million, research and development service fees of $10.8 million and milestone payments received to date of $12.0 million. The Company determined that the remaining potential milestone payments were probable of significant revenue reversal as their achievement was highly dependent on factors outside the Company’s control. Therefore, these payments were fully constrained and were not included in the transaction price upon the adoption of ASC 606 on January 1, 2018. The BMS Agreement represents an obligation to continuously make the Probody therapeutic technology platform available to Bristol Myers Squibb. Therefore, the initial transaction price is recognized over the estimated research service period, which ends on April 25, 2025.

In February 2020, Bristol Myers Squibb dosed the first patient in the Part 2 cohort expansion portion of its ongoing BMS-986249 clinical study for the CTLA-4 program, which triggered a $10.0 million milestone payment to the Company pursuant to the terms of the BMS Agreement. The $10.0 million milestone payment was recognized as revenue in the first quarter of 2020.

In February 2021, the Company and Bristol Myers Squibb entered into Amendment Number 2 to amend the Collaboration and License Agreement (“Amendment 2”), as amended by Amendment 1. Subsequent to Amendment 2, Bristol Myers Squibb has the exclusive worldwide rights to develop and commercialize Probody therapeutics for up to five oncology targets. Under the terms of Amendment 2, the period for target selection has been extended and the Company will continue to collaborate with Bristol Myers Squibb to discover and conduct preclinical development of Probody therapeutics against targets selected by Bristol Myers Squibb over the estimated research period, which ends in April 2025. Pursuant to Amendment 2, the Company is eligible to receive contingent payments for development, regulatory and sales milestones of up to an aggregate of $1,779.0 million. It is also entitled to tiered mid-single to low double-digit percentage of royalties from potential future sales. In addition, the Company will no longer be entitled to receive the research and development service fee as part of the arrangement.

The Company reevaluated the remaining potential milestone payments and determined that, if recognized, significant revenue reversal was still probable as the achievement of such milestones was highly dependent on factors outside the Company’s control. As a result, these payments were fully constrained and were not included in the transaction price on June 30, 2021.

The Company recognized revenue of $7.4 million and $7.4 million for the three months ended June 30, 2021 and 2020, respectively and $14.8 million and $24.8 million for the six months ended June 30, 2021 and 2020, respectively. As of June 30, 2021 and December 31, 2020, deferred revenue relating to the BMS Agreement was $113.6 million and $128.3 million, respectively. No amounts were due from Bristol Myers Squibb as of June 30, 2021 and December 31, 2020.

ImmunoGen, Inc.

In January 2014, the Company and ImmunoGen, Inc. (“ImmunoGen”) entered into the Research Collaboration Agreement (the “ImmunoGen Research Agreement”). The ImmunoGen Research Agreement provided the Company with the right to use ImmunoGen’s Antibody Drug Conjugate (“ADC”) technology in combination with the Company’s Probody therapeutic technology to create a conditionally activated ADC directed at one specified target under a research license, and to subsequently obtain an exclusive, worldwide development and commercialization license to use ImmunoGen’s ADC technology to develop and commercialize such conditionally activated ADCs. The Company made no upfront cash payment in connection with the execution of the agreement. Instead, the Company provided ImmunoGen with the rights to CytomX’s Probody therapeutic technology to create conditionally activated ADCs directed at two targets under the ImmunoGen Research Agreement and to subsequently obtain exclusive, worldwide development and commercialization licenses to develop and commercialize such conditionally activated ADCs. In February 2016, the Company exercised its option to obtain a development and commercialization license for praluzatamab ravtansine (CX-2009) pursuant to the terms of the ImmunoGen Research Agreement (the “CX-2009 License”).

In December 2019, the parties entered into a license agreement (the “ImmunoGen 2019 License”) pursuant to which the ImmunoGen Research Agreement (the ”ImmunoGen 2017 License”) for a target in December 2017, was terminated and ImmunoGen granted a license for all of ImmunoGen’s rights under the ImmunoGen 2017 License to the Company.

In February 2020, the Company dosed the first patient in the praluzatamab ravtansine Phase 2 clinical trial and triggered a $3.0 million milestone payment to ImmunoGen pursuant to the CX-2009 License which continued to remain in effect following the termination of the ImmunoGen 2017 License in December 2019. The Company recorded a $3.0 million charge to research and development expense for the first quarter of 2020, in connection with this milestone payment to ImmunoGen.

Contract Liabilities

The following table presents changes in the Company’s total contract liabilities during the six months ended June 30, 2021:



	Balance at Beginning of Period		Additions		Deductions			Balance at End of Period
	(in thousands)
Contract liabilities:
Deferred revenue	$	261,130	$	—	$	(30,572	)	$	230,558

The Company expects that the $230.6 million of deferred revenue related to the following contracts as of June 30, 2021 will be recognized as revenue as set forth below. However, the timing of revenue recognition could differ from the estimates depending on facts and circumstances impacting the various contracts, including progress of research and development, resources assigned to the contracts by the Company or its collaboration partners, or other factors outside of the Company’s control.



The $23.3 million of deferred revenue related to the CD71 Agreement with AbbVie is expected to be recognized based on actual FTE effort and program progress until approximately March 2023.



The $0.6 million of deferred revenue related to the first target under the Discovery Agreement with AbbVie is expected to be recognized ratably until approximately April 2022.



The $6.0 million of deferred revenue related to the second target under the Discovery Agreement with AbbVie is expected to be recognized ratably until approximately June 2024.



The $25.7 million of deferred revenue related to the Amgen EGFR Products is expected to be recognized based on actual FTE effort and program progress until approximately September 2024.



The $1.8 million of deferred revenue related to the Amgen Other Products is expected to be recognized ratably until approximately September 2023.



The $59.6 million of deferred revenue related to the Astellas Agreement is expected to be recognized ratably until approximately March 2025.



The $113.6 million of deferred revenue related to the BMS Agreement is expected to be recognized ratably until approximately April 2025.

Basis of Presentation and Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2021

Accounting Policies [Abstract]

Basis of Presentation and Summary of Significant Accounting Policies

2. Basis of Presentation and Summary of Significant Accounting Policies

Basis of Presentation

Unaudited Interim Financial Information

Use of Estimates

Cash and Cash Equivalents

The Company considers all highly liquid investments purchased with original maturities of three months or less at the date of purchase to be cash equivalents.

Restricted Cash

Restricted cash represents a standby letter of credit issued pursuant to an office lease entered in December 2015.


	June 30, 2021		December 31, 2020		June 30, 2020		December 31, 2019
	(in thousands)
Cash and cash equivalents	$	256,146	$	191,859	$	291,388	$	188,425
Restricted cash - non-current assets		917		917		917		917
Total	$	257,063	$	192,776	$	292,305	$	189,342

Investments

Comprehensive Income (Loss)

Revenue Recognition

Contract Balances

Research and Development Expenses

Stock-based Compensation

The Company estimates the fair value of its stock-based awards using the Black-Scholes option-pricing model, which requires the input of assumptions. The assumptions are as follows:



Risk-free interest rate. The risk-free interest rate is based on the U.S. Treasury yield with a maturity equal to the expected term of the stock options in effect at the time of grant.



Dividend yield. The expected dividend is assumed to be zero as the Company has never paid dividends and has no current plan to pay any dividends on its common stock.

Leases

Adopted Accounting Pronouncements

Stock-Based Compensation

6 Months Ended

Jun. 30, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation

9. Stock-Based Compensation

Stock Options

Activities under the Company’s stock option plans for the six months ended June 30, 2021 were as follows:


	Options Outstanding
	Number of Options			Weighted- Average Exercise Price Per Share
Balances at December 31, 2020		10,929,530		$	10.77
Options granted		3,633,597			7.80
Options exercised		(391,478	)		3.06
Option forfeited/expired		(2,155,707	)		11.20
Balances at June 30, 2021		12,015,942		$	10.05
Options exercisable at June 30, 2021		5,735,023		$	11.92

Stock-based Compensation

Total stock-based compensation recorded related to options granted to employees and non-employees and employee stock purchase plan was as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2021		2020		2021		2020
	(in thousands)
Stock-based compensation expense:
Research and development	$	1,548	$	1,663	$	2,885	$	3,582
General and administrative		1,877		1,850		3,574		3,944
Total stock-based compensation expense	$	3,425	$	3,513	$	6,459	$	7,526

Net Loss Per Share

6 Months Ended

Jun. 30, 2021

Earnings Per Share [Abstract]

Net Loss Per Share

3. Net Loss Per Share

Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period. Diluted net loss per share is calculated using the weighted-average number of common shares outstanding, plus potential dilutive common stock during the period. Diluted net loss per share is the same as basic net loss per share since the effect of the potentially dilutive securities is anti-dilutive.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2021		2020		2021		2020
Options and ESPP to purchase common stock		12,117,149		11,745,760		11,837,707		11,339,658

Research and Collaboration Agreements - Contract Liabilities - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 230,558	$ 261,130
AbbVie Ireland Unlimited Company \| CD71 Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 23,300	$ 25,200
Deferred revenue recognition maturity month and year	2023-03
AbbVie Ireland Unlimited Company \| First Target under Discovery Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 600
Deferred revenue recognition maturity month and year	2022-04
AbbVie Ireland Unlimited Company \| Second Target under Discovery Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 6,000
Deferred revenue recognition maturity month and year	2024-06
Amgen Inc \| EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 25,700
Deferred revenue recognition maturity month and year	2024-09
Amgen Inc \| Amgen Other Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 1,800
Deferred revenue recognition maturity month and year	2023-09
Bristol Myers Squibb Company
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 113,600
Deferred revenue recognition maturity month and year	2025-04
Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 59,600
Deferred revenue recognition maturity month and year	2025-03

Income Taxes - Additional Information (Details)	Mar. 27, 2020
Income Tax Disclosure [Abstract]
Net operating loss carryback	5 years
Percentage of taxable income from net operating losses for suspension of annual deduction limitation	80.00%

CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net loss	$ (34,797)	$ (3,474)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Amortization of intangible assets	73	72
Depreciation and amortization	1,278	1,187
Amortization of premium (accretion of discounts) on investments	281	(314)
Stock-based compensation expense	6,459	7,526
Non-cash lease expense	1,534	1,415
Changes in operating assets and liabilities
Accounts receivable	(133)	(193)
Prepaid expenses and other current assets	3,199	(12,782)
Other assets	1,271	636
Accounts payable	(1,173)	579
Accrued liabilities and other long-term liabilities	(5,559)	(11,302)
Deferred revenue	(30,572)	64,014
Net cash (used in) provided by operating activities	(58,139)	47,364
Cash flows from investing activities:
Purchases of property and equipment	(1,096)	(1,086)
Purchases of investments	99,898	44,707
Maturities of investments	113,994	97,687
Net cash provided by investing activities	13,000	51,894
Cash flows from financing activities:
Proceeds from issuance of common stock, net of issuance costs	107,712
Proceeds from employee stock purchase plan and exercise of stock options	1,714	3,705
Net cash provided by financing activities	109,426	3,705
Net increase in cash, cash equivalents and restricted cash	64,287	102,963
Cash, cash equivalents and restricted cash, beginning of period	192,776	189,342
Cash, cash equivalents and restricted cash, end of period	257,063	292,305
Supplemental disclosures of noncash investing items:
Purchases of property and equipment in accounts payable and accrued liabilities	$ 54	$ 618

Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details) - ASU 2019-12	Jun. 30, 2021
Summary Of Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2021
Change in accounting principle, accounting standards update, adopted [true false]	false
Change in accounting principle, accounting standards update, immaterial effect [true false]	true

Indicates (true false) whether accounting standards update was adopted.

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Organization Consolidation And Presentation Of Financial Statements [Abstract]

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+ Details

Research and Collaboration Agreements (Tables)

6 Months Ended

Jun. 30, 2021

Schedule of Revenue by Collaboration Partners

The following table summarizes the revenue by collaboration partners:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2021		2020		2021		2020
	(in thousands)				(in thousands)
AbbVie	$	2,078	$	1,319	$	3,306	$	31,415
Amgen		1,874		3,678		4,456		5,373
Astellas		4,931		4,204		9,688		4,591
Bristol Myers Squibb		7,405		7,407		14,809		24,822
Total Revenue	$	16,288	$	16,608	$	32,259	$	66,201

Summary of Contract Liabilities

The following table presents changes in the Company’s total contract liabilities during the six months ended June 30, 2021:



	Balance at Beginning of Period		Additions		Deductions			Balance at End of Period
	(in thousands)
Contract liabilities:
Deferred revenue	$	261,130	$	—	$	(30,572	)	$	230,558

Stock-Based Compensation - Total Stock-based Compensation Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock-based compensation expense:
Stock-based compensation expense	$ 3,425	$ 3,513	$ 6,459	$ 7,526
Research and development
Stock-based compensation expense:
Stock-based compensation expense	1,548	1,663	2,885	3,582
General and administrative
Stock-based compensation expense:
Stock-based compensation expense	$ 1,877	$ 1,850	$ 3,574	$ 3,944

Leases - Additional Information (Details)
$ in Thousands

3 Months Ended

6 Months Ended

Dec. 10, 2015

USD ($)

ft²

Jun. 30, 2021

USD ($)

Jun. 30, 2020

USD ($)

Jun. 30, 2021

USD ($)

Jun. 30, 2020

USD ($)

Dec. 31, 2020

USD ($)

Dec. 31, 2019

USD ($)

$ 917

^[1]

$ 917

Rent expense

1,300

$ 1,300

2,500

$ 2,500

Letter of Credit

Letter of credit outstanding, amount

900

$ 900

New Lease Agreement

Area of rentable office and laboratory space | ft²

76,000

Lease term description

Initial lease term

10 years

Extended lease term

5 years

Maximum one-time improvement allowance

$ 12,600

Improvement allowance from recoverable rent

2,300

New Lease Agreement | First year of lease term

New Lease Agreement | Second twelve months of lease term

Annual lease rent

3,100

New Lease Agreement | Tenth year of lease term

Annual lease rent

4,300

Annual lease rent

$ 5,500

[1]	The condensed balance sheet as of December 31, 2020 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.

Income Tax Expense

6 Months Ended

Jun. 30, 2021

Income Tax Disclosure [Abstract]

Income Taxes

12. Income Taxes

The Company records the effect of an enacted change in a tax law in the period that includes the enactment date in accordance with ASC 740. On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) was enacted in response to the COVID-19 pandemic. The tax relief measures under the CARES Act for businesses include a five-year net operating loss carryback, suspension of annual deduction limitation of 80% of taxable income from net operating losses generated in a tax year beginning after December 31, 2017, changes in the deductibility of interest, acceleration of alternative minimum tax credit refunds, payroll tax relief, and a technical correction to allow accelerated deductions for qualified improvement property.

The income tax benefit for the six months ended June 30, 2020 was generated as a result of the recognition of net operating loss carryback under the CARES Act which generated a refund of income taxes paid for 2018. The Company maintains a full valuation allowance against its net deferred tax assets due to the Company’s history of losses as of June 30, 2021 and December 31, 2020.