0001564590-21-028411 | 10-Q | XBRL Viewer | ALX Oncology Holdings INC

Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2021

Common Stock Reserved for Future Issuance on Converted Basis

Common stock reserved for future issuance as of March 31, 2021 and December 31, 2020, consists of the following:

	March 31,		December 31,
	2021		2020
Stock options issued and outstanding		4,350,467		4,857,308
Stock options authorized for future issuance		4,572,020		2,835,443
Employee Stock Purchase Plan shares authorized for future issuance		798,445		400,000
Total		9,720,932		8,092,751

Net Loss Per Share Attributable to Common Stockholders - Summary of Outstanding Potentially Dilutive Securities Were Excluded from Computation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	4,352,067	24,649,235
Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share		21,369,774
Warrants to Purchase Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share		61,292
Common Stock Subject to Repurchase
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share		17,297
Estimated Common Stock Issuable Under the Employee Stock Purchase Plan
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	1,600
Options Issued and Outstanding
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	4,350,467	3,200,872

Balance Sheet Components (Tables)

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

Schedule of Components of Property and Equipment

The following table presents the components of property and equipment, net as of March 31, 2021 and December 31, 2020 (in thousands):

	March 31,			December 31,
	2021			2020
Computer hardware and software	$	63		$	63
Furniture and fixtures		9			9
Leasehold improvements		5			5
Property and equipment, gross		77			77
Less: accumulated depreciation and amortization		(30	)		(25	)
Total property and equipment, net	$	47		$	52

Components of Accrued Expenses and Other Current Liabilities

The following table presents the components of accrued expenses and other current liabilities as of March 31, 2021 and December 31, 2020 (in thousands):

	March 31,		December 31,
	2021		2020
Accrued clinical and nonclinical study costs	$	3,770	$	1,473
Accrued compensation and related expenses		1,802		1,974
Accrued contract manufacturing		383		2,123
Accrued professional fees		307		300
Accrued federal income tax		179		179
Operating lease liabilities, current		140		—
Other		103		151
Finance lease liabilities, current		95		—
Total accrued expenses and other current liabilities	$	6,779	$	6,200

Stockholders' Equity - Common Stock Reserved for Future Issuance on Converted Basis (Details) - shares	Mar. 31, 2021	Dec. 31, 2020
Class Of Stock [Line Items]
Common stock reserved for future issuance	9,720,932	8,092,751
Stock Options Issued and Outstanding
Class Of Stock [Line Items]
Common stock reserved for future issuance	4,350,467	4,857,308
Stock Options Authorized for Future Issuance
Class Of Stock [Line Items]
Common stock reserved for future issuance	4,572,020	2,835,443
Employee Stock Purchase Plan Shares Authorized for Future Issuance
Class Of Stock [Line Items]
Common stock reserved for future issuance	798,445	400,000

Net Loss Per Share Attributable to Common Stockholders

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

NET LOSS PER SHARE ATTRIBUTABLE TO COMMON STOCKHOLDERS

(11) NET LOSS PER SHARE ATTRIBUTABLE TO COMMON STOCKHOLDERS

The following table sets forth the computation of the basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share data):

	Three Months Ended March 31,
	2021			2020
Numerator:
Net loss	$	(14,185	)	$	(5,454	)
Less: cumulative preferred dividends allocated to preferred stockholders		—			(1,983	)
Net loss attributable to common stockholders	$	(14,185	)	$	(7,437	)
Denominator:
Weighted-average shares of common stock outstanding		40,055,435			3,143,159
Net loss per share attributable to common stockholders, basic and diluted	$	(0.35	)	$	(2.37	)

Since the Company was in a loss position for all periods presented, basic net loss per share is the same as diluted net loss per share for all periods presented as the inclusion of all potential common stock outstanding would have been anti-dilutive.

The following outstanding potentially dilutive securities were excluded from the computation of diluted net loss per share for the three months ended March 31, 2021 and 2020, because including them would have been anti-dilutive:

	March 31,
	2021		2020
Convertible preferred stock		—		21,369,774
Warrants to purchase convertible preferred stock		—		61,292
Common stock subject to repurchase		—		17,297
Options issued and outstanding		4,350,467		3,200,872
Estimated common stock issuable under the employee stock purchase plan		1,600		—
Total		4,352,067		24,649,235

Term Loan and Related Derivatives - Additional Information (Details) - USD ($)	Mar. 31, 2021	Mar. 31, 2020	Dec. 20, 2019
Debt Instrument [Line Items]
Fair value of warrant liability		$ 86,000
Compound Derivative Liability
Debt Instrument [Line Items]
Fair value of compound derivative liability	$ 51,000	$ 14,000
Series B Convertible Preferred Stock
Debt Instrument [Line Items]
Warrant liability converted into common stock	$ 400,000
Loan Agreement
Debt Instrument [Line Items]
Term loan, principal amount			$ 6,000,000

Stock-Based Compensation

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

STOCK-BASED COMPENSATION

(8) STOCK-BASED COMPENSATION

2020 Amended and Restated Equity Incentive Plan

On April 1, 2020, the board of directors approved a new equity incentive plan, or the 2020 Equity Incentive Plan, that replaced the 2015 Share Award Scheme.

In July 2020, the Company adopted the Amended and Restated 2020 Equity Incentive Plan, or the 2020 Plan. The 2020 Plan replaced the Company’s 2020 Equity Incentive Plan and a total of 7,874,862 shares were reserved under the 2020 Plan.

Unless the board of directors provides otherwise, beginning on January 1, 2021, and ending on (and inclusive of) January 1, 2030, the maximum number of shares available for issuance under the 2020 Plan automatically increases on the first day of each fiscal year by an amount equal to the least of:

•

4,000,000 shares;

•

four percent of the outstanding shares of the Company’s common stock on the last day of the immediately preceding fiscal year; or

•

such number of shares as the board of directors may determine no later than the last day of the immediately preceding fiscal year.

Accordingly, on January 1, 2021, the number of shares available under the 2020 Plan was increased by 1,593,781 shares.

Employee Stock Purchase Plan

In July 2020, the Company's board of directors and stockholders approved the ALX Oncology Holdings Inc. 2020 Employee Stock Purchase Plan, or the ESPP. The ESPP allows eligible employees to have up to 15 percent of their eligible compensation withheld and used to purchase common stock, subject to a maximum of $25,000 worth of stock purchased in a calendar year or no more than 3,000 shares in a purchase period, whichever is less. The ESPP allows for offering periods of up to 27 months consisting of one or more purchase periods. In January 2021, the board of directors approved the first offering period with a simultaneous purchase period beginning February 1, 2021 and ending June 30, 2021. Eligible employees can purchase the Company’s common stock at the end of the purchase period at 85% of the lower of the closing price of the Company’s common stock on The Nasdaq Global Select Market on the first day of the offering period and the last day of the purchase period.

The initial number of shares of common stock available for issuance under the ESPP was 400,000. Unless the board of directors provides otherwise, beginning on January 1, 2021, the maximum number of shares available for sale under the ESPP automatically increases on the first trading day in January of each calendar year during the term of the ESPP by an amount equal to the least of:

•

800,000 shares;

•

one percent of the outstanding shares of the Company’s common stock on the last day of the immediately preceding fiscal year; or

•

such number of shares as the board of directors may determine no later than the last day of the immediately preceding fiscal year.

Accordingly, on January 1, 2021, the number of shares available under the ESPP was increased by 398,445 shares. As of March 31, 2021, there were no purchases under the ESPP, and the number of shares of common stock available for issuance under the ESPP was 798,445.

Stock-based Compensation Expense

Total stock-based compensation expense recognized in the condensed consolidated statements of operations and comprehensive loss was as follows (in thousands):

	Three Months Ended March 31,
	2021		2020
Research and development	$	579	$	83
General and administrative		1,221		68
	$	1,800	$	151

Balance Sheet Components - Schedule of Components of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 77	$ 77
Less: accumulated depreciation and amortization	(30)	(25)
Total property and equipment, net	47	52
Computer Hardware and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	63	63
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	9	9
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 5	$ 5

Leases

3 Months Ended

Mar. 31, 2021

Leases [Abstract]

LEASES

(5) LEASES

In 2017, the Company entered into a lease agreement for office space for a period of five years and four months, commencing February 1, 2018 and ending May 31, 2023. In July 2020, the Company (i) assigned to Tallac Therapeutics, Inc., or Tallac Therapeutics, (Note 10) the Company’s lease with respect to the premises located at 866 Malcolm Road, Burlingame, California, and (ii) entered a sub-lease agreement for the same premise from Tallac Therapeutics.

Lease costs included in operating expense in the condensed consolidated statement of operations and comprehensive loss in relation to the operating lease were approximately $58,000 for the three months ended March 31, 2021. Included in these lease costs were variable lease costs, which were not included within the measurement of the Company’s operating lease ROU assets and operating lease liabilities in the amount of approximately $22,000 for the three months ended March 31, 2021. The variable lease cost is comprised primarily of common area maintenance charges for the operating lease, which is dependent on usage. These costs are classified as operating lease expense due to our election to not separate lease and non-lease components.

Cash paid for amounts included in the measurement of operating lease liabilities was approximately $23,000 for the three months ended March 31, 2021.

The Company evaluated its vendor contracts to identify embedded leases, if any, and noted that a pharmaceutical support services agreement entered into in May 2016, included leases under ASC 842 because the Company has the right to direct the use of certain equipment. The embedded leases commenced in September 2020 and expire in August 2023 with no stated option to extend the term. The Company classified the leases as finance leases. Amortization on the finance ROU and interest expense was approximately $23,000 and nominal, respectively, for the three months ended March 31, 2021. Cash paid within financing cash flows for the finance lease was nil for the three months ended March 31, 2021. Cash paid within operating cash flows for interest on the finance lease liability was nil for the three months ended March 31, 2021.

Short-term lease expense for the three months ended March 31, 2021 was nominal.

The ROU assets recorded under the operating lease and finance lease were $0.3 million and $0.2 million, respectively, at March 31, 2021. The amounts were included in the other assets on the condensed consolidated balance sheet.

The following table presents the maturities and balance sheet information of the Company's operating and finance lease liabilities as of March 31, 2021:

	March 31, 2021
(in thousands, except lease term and discount rate)	Operating Leases			Finance Leases
2021 (remaining nine months)	$	105		$	72
2022		144			96
2023		62			64
Total lease payments		311			232
Less: imputed interest		5			6
Total lease liabilities	$	306		$	226

Lease liabilities: current	$	140		$	95
Lease liabilities: non-current		166			131
Total lease liabilities	$	306		$	226

Weighted average remaining lease term (in years)	2.17			2.42
Weighted average discount rate		1.69	%		1.87	%

Current lease liabilities are presented within accrued expenses and other current liabilities, and non-current lease liabilities are presented within other non-current liabilities on the condensed consolidated balance sheet.

As of March 31, 2021, the Company has additional finance leases that have not yet commenced with lease obligations of approximately $0.8 million, which are not included in the table above. These leases will commence between April and May 2021 and expire in 2023.

ASC 840 Disclosures

The Company elected the alternative modified transition method, which applies ASC 842 as of the effective date on January 1, 2021. Prior to the adoption of ASC 842, the Company applied ASC 840 to its lease transactions.

The following table presents the future minimum lease commitments under the Company’s operating leases as of December 31, 2020, as previously disclosed:

(in thousands)	December 31, 2020
2021	$	140
2022-2023		206
Total future minimum lease payments	$	346

Rent expense was $0.2 million for the three months ended March 31, 2020.

Balance Sheet Components - Components of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Accrued clinical and nonclinical study costs	$ 3,770	$ 1,473
Accrued compensation and related expenses	1,802	1,974
Accrued contract manufacturing	383	2,123
Accrued professional fees	307	300
Accrued federal income tax	179	179
Operating lease liabilities, current	140
Other	103	151
Finance lease liabilities, current	95
Total accrued expenses and other current liabilities	$ 6,779	$ 6,200

Leases - Schedule of Future Minimum Lease Commitments under Operating Leases (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Leases [Abstract]
2021	$ 140
2022-2023	206
Total future minimum lease payments	$ 346

Fair Value of Financial Instruments - Financial Assets Measured at Fair Value on Recurring Basis (Details) - Fair Value on Recurring Basis - Money Market Funds - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial assets
Cash equivalents	$ 415,129	$ 424,115
Level 1
Financial assets
Cash equivalents	$ 415,129	$ 424,115

Balance Sheet Components

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

BALANCE SHEET COMPONENTS

(4) BALANCE SHEET COMPONENTS

Property and Equipment, Net

The following table presents the components of property and equipment, net as of March 31, 2021 and December 31, 2020 (in thousands):

	March 31,			December 31,
	2021			2020
Computer hardware and software	$	63		$	63
Furniture and fixtures		9			9
Leasehold improvements		5			5
Property and equipment, gross		77			77
Less: accumulated depreciation and amortization		(30	)		(25	)
Total property and equipment, net	$	47		$	52

Depreciation and amortization expense for the three months ended March 31, 2021 was nominal. Depreciation and amortization expense was $0.1 million for the three months ended March 31, 2020.

Accrued Expenses and Other Current Liabilities

The following table presents the components of accrued expenses and other current liabilities as of March 31, 2021 and December 31, 2020 (in thousands):

	March 31,		December 31,
	2021		2020
Accrued clinical and nonclinical study costs	$	3,770	$	1,473
Accrued compensation and related expenses		1,802		1,974
Accrued contract manufacturing		383		2,123
Accrued professional fees		307		300
Accrued federal income tax		179		179
Operating lease liabilities, current		140		—
Other		103		151
Finance lease liabilities, current		95		—
Total accrued expenses and other current liabilities	$	6,779	$	6,200

Leases (Tables)

3 Months Ended

Mar. 31, 2021

Leases [Abstract]

Schedule of Maturities of Operating and Finance Lease Liabilities

The following table presents the maturities and balance sheet information of the Company's operating and finance lease liabilities as of March 31, 2021:

	March 31, 2021
(in thousands, except lease term and discount rate)	Operating Leases			Finance Leases
2021 (remaining nine months)	$	105		$	72
2022		144			96
2023		62			64
Total lease payments		311			232
Less: imputed interest		5			6
Total lease liabilities	$	306		$	226

Lease liabilities: current	$	140		$	95
Lease liabilities: non-current		166			131
Total lease liabilities	$	306		$	226

Weighted average remaining lease term (in years)	2.17			2.42
Weighted average discount rate		1.69	%		1.87	%

Schedule of Future Minimum Lease Commitments under Operating Leases

The following table presents the future minimum lease commitments under the Company’s operating leases as of December 31, 2020, as previously disclosed:

(in thousands)	December 31, 2020
2021	$	140
2022-2023		206
Total future minimum lease payments	$	346

Stock-Based Compensation - Additional Information (Details) - USD ($)		1 Months Ended	3 Months Ended
	Jan. 01, 2021	Jul. 31, 2020	Mar. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance			9,720,932	8,092,751
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance		400,000	798,445
Maximum percentage of additional shares reserved for future issuance			1.00%
Number of additional shares reserved for future issuance	398,445
Percentage of eligible compensation withheld		15.00%
Share-based compensation, authorized amount		$ 25,000
Share-based compensation, number of shares authorized		3,000
Share-based compensation, maximum offering period		27 months
Share-based Compensation, lower of closing price, percentage		85.00%
Number of shares purchased			0
Maximum \| ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance			800,000
2020 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance		7,874,862
Maximum percentage of additional shares reserved for future issuance			4.00%
Number of additional shares reserved for future issuance	1,593,781
2020 Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance			4,000,000

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 429,855	$ 434,219
Prepaid expenses and other current assets	2,472	1,773
Total current assets	432,327	435,992
Property and equipment, net	47	52
Other assets	536	10
Total assets	432,910	436,054
Current liabilities:
Accounts payable	7,350	4
Accrued expenses and other current liabilities	6,779	6,200
Total current liabilities	14,129	6,204
Other non-current liabilities	297	5
Total liabilities	14,426	6,209
Commitments and contingencies (Note 12)
Stockholders’ equity
Preferred stock, $0.001 par value; 100,000,000 shares authorized, no shares issued or outstanding
Common stock, $0.001 par value; 1,000,000,000 shares authorized as of March 31, 2021 and December 31, 2020; 40,208,569 and 39,844,522 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	40	40
Additional paid-in capital	551,151	548,327
Accumulated deficit	(132,707)	(118,522)
Total stockholders’ equity	418,484	429,845
Total liabilities and stockholders’ equity	$ 432,910	$ 436,054

Stock-Based Compensation - Summary of Total Stock Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 1,800	$ 151
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	579	83
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 1,221	$ 68

Leases - Schedule of Maturities of Operating and Finance Lease Liabilities (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2021 (remaining nine months)	$ 105
2022	144
2023	62
Total lease payments	311
Less: imputed interest	5
Operating lease liabilities	306
Operating lease liabilities, current	140
Operating leases: non-current	166
Total lease liabilities	$ 306
Weighted average remaining lease term (in years)	2 years 2 months 1 day
Weighted average discount rate	1.69%
Finance Lease, Liability, Payment, Due [Abstract]
2021 (remaining nine months)	$ 72
2022	96
2023	64
Total lease payments	232
Less: imputed interest	6
Finance lease liabilities	226
Finance lease liabilities, current	95
Finance leases: non-current	131
Total lease liabilities	$ 226
Weighted average remaining lease term (in years)	2 years 5 months 1 day
Weighted average discount rate	1.87%

Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Financial Assets Measured at Fair Value on Recurring Basis

The following table sets forth the Company’s financial assets that are measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands):

	As of March 31, 2021
	Level 1		Level 2		Level 3		Fair Value
Financial assets
Cash equivalents
Money market funds	$	415,129	$	—	$	—	$	415,129

	As of December 31, 2020
	Level 1		Level 2		Level 3		Fair Value
Financial assets
Cash equivalents
Money market funds	$	424,115	$	—	$	—	$	424,115

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Total	Convertible Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Deficit
Balance at Dec. 31, 2019	$ (70,639)		$ 3	$ 2,140	$ (72,782)
Temporary equity, shares at Dec. 31, 2019		10,313,808
Temporary equity, balance at Dec. 31, 2019		$ 70,363
Balance, shares at Dec. 31, 2019			3,166,946
Vesting of early exercised stock options	16			16
Stock-based compensation	151			151
Net loss	(5,454)				(5,454)
Issuance of convertible preferred stock, net of issuance costs		$ 104,680
Issuance of convertible preferred stock, net of issuance costs, shares		11,055,966
Balance at Mar. 31, 2020	(75,926)		$ 3	2,307	(78,236)
Temporary equity, shares at Mar. 31, 2020		21,369,774
Temporary equity, balance at Mar. 31, 2020		$ 175,043
Balance, shares at Mar. 31, 2020			3,166,946
Balance at Dec. 31, 2020	429,845		$ 40	548,327	(118,522)
Balance, shares at Dec. 31, 2020			39,844,522
Issuance of common stock under equity incentive plan	1,024			1,024
Issuance of common stock under equity incentive plans, shares			364,047
Stock-based compensation	1,800			1,800
Net loss	(14,185)				(14,185)
Balance at Mar. 31, 2021	$ 418,484		$ 40	$ 551,151	$ (132,707)
Balance, shares at Mar. 31, 2021			40,208,569

Net Loss Per Share Attributable to Common Stockholders - Computation of Basic and Diluted Net Loss per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss	$ (14,185)	$ (5,454)
Less: cumulative preferred dividends allocated to preferred stockholders		(1,983)
Net loss attributable to common stockholders	$ (14,185)	$ (7,437)
Denominator:
Weighted-average shares of common stock outstanding	40,055,435	3,143,159
Net loss per share attributable to common stockholders, basic and diluted	$ (0.35)	$ (2.37)

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22595-107794

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669625-108580

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

+ References

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+ Details

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	40,208,569	39,844,522
Common stock, shares outstanding	40,208,569	39,844,522

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2021	May 11, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Registrant Name	ALX ONCOLOGY HOLDINGS INC
Entity Central Index Key	0001810182
Entity File Number	001-39386
Entity Tax Identification Number	85-0642577
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	866 Malcolm Road
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Burlingame
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94010
City Area Code	650
Local Phone Number	466-7125
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Common Stock, Shares Outstanding		40,229,869
Entity Shell Company	false
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	ALXO
Security Exchange Name	NASDAQ
Document Quarterly Report	true
Document Transition Report	false

Stockholders' Equity

3 Months Ended

Mar. 31, 2021

Equity [Abstract]

STOCKHOLDERS' EQUITY

(7) STOCKHOLDERS’ EQUITY

On July 21, 2020, the Company’s amended and restated certificate of incorporation became effective, authorizing 1,000,000,000 shares of common stock and 100,000,000 shares of undesignated preferred stock. As of March 31, 2021 and December 31, 2020, the Company had 40,208,569 and 39,844,522 shares of common stock outstanding, respectively.

Common Stock

Common stock reserved for future issuance as of March 31, 2021 and December 31, 2020, consists of the following:

	March 31,		December 31,
	2021		2020
Stock options issued and outstanding		4,350,467		4,857,308
Stock options authorized for future issuance		4,572,020		2,835,443
Employee Stock Purchase Plan shares authorized for future issuance		798,445		400,000
Total		9,720,932		8,092,751

Balance Sheet Components - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Balance Sheet Related Disclosures [Abstract]
Depreciation and amortization expense	$ 0.1

Related-Party Transactions

3 Months Ended

Mar. 31, 2021

RELATED-PARTY TRANSACTIONS

(10) RELATED-PARTY TRANSACTIONS

Related-party revenue

In June 2018, the Company entered into a Research and Development Services Agreement, or Tollnine Agreement, with Tollnine Therapeutics, Inc., or Tollnine, a related-party of the Company, to provide research and development services to Tollnine. The Company’s Chief Executive Officer was also the Chief Executive Officer of Tollnine until April 2020 and two of the Company’s investors were also investors in Tollnine. As such, Tollnine was deemed to be a related-party. The Tollnine Agreement had an initial term of 3 years. The services were provided at a price based on the costs incurred by the Company plus a mark-up equal to 10% of such costs. The Company recognized revenue when Tollnine, as the Company’s customer, obtained control of promised goods or services, in an amount that reflects the consideration which the Company received in exchange for those goods or services. The Company recognized related-party revenues of zero and $0.7 million for the three months ended March 31, 2021 and 2020, respectively, under the Tollnine Agreement. Effective as of July 1, 2020, the Company terminated the Tollnine Agreement and entered into the Tallac Services Agreement with Tallac Therapeutics (formerly known as Tollnine).

Tallac Service Agreement

The Company entered into a research and development services agreement, or the Tallac Services Agreement, with Tallac Therapeutics effective as of July 1, 2020. The Tallac Services Agreement provides that Tallac Therapeutics will provide certain preclinical research services to the Company for a service fee based on the costs incurred by Tallac Therapeutics plus a mark-up equal to 10% of such costs. The Tallac Services Agreement has an initial term of four years and is renewed automatically for additional one year terms thereafter. The Company records the payments for the research and development services as research and development costs within the condensed consolidated statement of operations and comprehensive loss. The Company has recorded $0.4 million as research and development costs for the three months ended March 31, 2021.

Tallac Collaboration Agreement

On March 4, 2021, the Company entered into a Collaboration Agreement with Tallac Therapeutics to jointly develop, manufacture, and commercialize a novel class of cancer immunotherapeutics. The collaboration builds on the Company’s expertise in developing therapies that block the CD47 checkpoint pathway and expands its immuno-oncology pipeline. The companies will leverage their respective scientific and technical expertise to advance an anti-SIRPα antibody conjugated to a Toll-like receptor 9, or TLR9, agonist for targeted activation of both the innate and adaptive immune systems. The key economic components of the collaboration transaction include that both parties will share equally (a) in the cost and expenses of research and development and (b) any profit or loss. During the three months ended March 31, 2021, the expense incurred related to the collaboration was nominal.

Significant Accounting Policies - Additional Information (Details) $ in Thousands		3 Months Ended
	Jul. 08, 2020	Mar. 31, 2021 USD ($)	Jan. 01, 2021 USD ($)
Significant Accounting Policies [Line Items]
Reverse stock split, description		On July 8, 2020, the Company’s board of directors approved an amendment to the Company’s certificate of incorporation to effect a 1-for-6.5806 reverse split of its common stock and convertible preferred stock.
Reverse stock split, conversion ratio	0.151961827
Lease, practical expedients, package [true false]		true
Operating lease ROU assets		$ 300
Finance lease ROU assets		200
Operating lease liabilities		306
Finance lease liabilities		$ 226
Finance lease, right-of-use asset, statement of financial position [extensible list]		us-gaap:OtherAssetsNoncurrent
Finance lease, liability, current, statement of financial position [extensible list]		us-gaap:AccruedLiabilitiesAndOtherLiabilities
Finance lease, liability, noncurrent, statement of financial position [extensible list]		us-gaap:OtherLiabilitiesNoncurrent
Operating lease, right-of-use asset, statement of financial position [extensible list]		us-gaap:PrepaidExpenseAndOtherAssetsCurrent
Operating lease, liability, current, statement of financial position [extensible list]		us-gaap:AccruedLiabilitiesAndOtherLiabilities
Operating lease, liability, noncurrent, statement of financial position [extensible list]		us-gaap:OtherLiabilitiesNoncurrent
ASU 2016-02
Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 01, 2021
Operating lease ROU assets			$ 300
Finance lease ROU assets			200
Operating lease liabilities			300
Finance lease liabilities			$ 200
ASU 2019-12
Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 01, 2021
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]		true

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Basis of Presentation

Basis of Preparation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States, or GAAP and applicable rules and regulations of the Securities and Exchange Commission, or SEC regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this quarterly report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the year ended December 31, 2020.

The condensed consolidated balance sheet as of December 31, 2020 included herein was derived from the audited financial statements as of that date, but does not include all disclosures including notes required by GAAP.

The accompanying condensed consolidated financial statements reflect all normal recurring adjustments that are necessary to present fairly the results for the interim periods presented. Interim results are not necessarily indicative of the results for the full year ending December 31, 2021.

All intercompany balances and transactions have been eliminated in consolidation.

Reverse Stock Split

On July 8, 2020, the Company’s board of directors approved an amendment to the Company’s certificate of incorporation to effect a 1-for-6.5806 reverse split of its common stock and convertible preferred stock. The par values of the common and convertible preferred stock were not adjusted as a result of the reverse stock split. All authorized, issued and outstanding common stock, convertible preferred stock, stock options, warrants, and related per share amounts contained in the condensed consolidated financial statements have been retroactively adjusted to reflect this reverse stock split for all periods presented. The reverse stock split was effected on July 9, 2020.

Use of Estimates

The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make 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 periods. On an ongoing basis, management evaluates its estimates, including those related to the estimated useful lives of long-lived assets, clinical trial accruals, fair value of assets and liabilities, income taxes and stock-based compensation. Management bases its estimates on historical experience and on various other market-specific and relevant assumptions that management believes to be reasonable under the circumstances. Actual results could materially differ from those estimates.

Significant Accounting Policies

With the exception of the change for the accounting of leases as a result of the adoption of Accounting Standards Update (ASU) No. 2016-02, Leases (Topic 842), or Topic 842, there have been no new or material changes to the significant accounting policies discussed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, that are of significance, or potential significance, to the Company.

Leases

The Company determines if an arrangement contains a lease at inception. For arrangements where the Company is the lessee, leases are included in operating or finance lease right-of-use, or ROU, assets; current operating or finance lease liabilities; and non-current operating or finance lease liabilities.

Lease ROU assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at the commencement date. ROU assets also include any initial direct costs incurred and any lease payments made on or before the lease commencement date, less lease incentives received. The Company uses its incremental borrowing rate based on the information available at the commencement date in determining the lease liabilities as the Company’s leases generally do not provide an implicit rate. The incremental borrowing rate is reevaluated upon a lease modification. The Company considered information available at the adoption date of Topic 842 to determine the incremental borrowing rate for leases in existence as of this date. Lease terms may include options to extend or terminate the lease when the Company is reasonably certain that the option will be exercised. Lease expense for operating leases is recognized on a straight-line basis over the lease term. For finance leases, ROU assets are amortized on a straight-line basis over the shorter of the expected useful life or the lease term, and the carrying amount of the lease liability is adjusted to reflect interest expense, which is recorded in interest expense.

The Company elected to apply each of the practical expedients described in Topic 842 which allow companies (i) not to reassess prior conclusions on whether any expired or existing contracts are or contain a lease, lease classification, and initial direct costs, (ii) combine lease and non-lease components for all underlying assets groups, and (iii) not recognize ROU assets or lease liabilities for short term leases. A short-term lease is a lease that, at the commencement date, has a lease term of 12 months or less and does not include an option to purchase the underlying asset that the lessee is reasonably certain to exercise.

Adopted Accounting Pronouncements

In February 2016, the Financial Accounting Standards Board, or FASB, issued ASU No. 2016-02 (Topic 842), Leases (ASU 2016-02). ASU 2016-02 requires an entity to recognize assets and liabilities arising from a lease for both operating and finance leases. ASU No. 2016-02 will also require new qualitative and quantitative disclosures to help investors and other financial statement users better understand the amount, timing, and uncertainty of cash flows arising from leases. In June 2020, the FASB issued ASU No. 2020-05, which extended the effective date of ASU No. 2016-02 for non-public business entities, including smaller reporting companies, to fiscal years beginning after December 15, 2021. The Company adopted Topic 842 on January 1, 2021, with early adoption permitted using the alternative modified transition method, which applies the standard as of the effective date and therefore, the Company has not applied the standard to the comparative periods presented on the Company's financial statements. The Company elected the following practical expedients:

(i)

not to reassess prior conclusions on whether any expired or existing contracts are or contain a lease, lease classification, and initial direct costs;

(ii)

combine lease and non-lease components

(iii)

not to recognize ROU assets or lease liabilities for short term leases

As a lessee, the primary impact of the adoption of Topic 842 was the recognition of operating and finance lease ROU assets of $0.3 million and $0.2 million, respectively, and operating and finance lease liabilities of $0.3 million and $0.2 million, respectively, as of January 1, 2021. ROU assets are presented within other assets, current lease liabilities are presented within accrued expenses and other current liabilities, and non-current lease liabilities are presented within other non-current liabilities on the condensed consolidated balance sheet. See Note 5 "Leases" for additional details.

In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which is intended to simplify various aspects related to accounting for income taxes. The pronouncement is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2021. ASU 2019-12 is effective for the Company beginning January 1, 2022. Early adoption is permitted. The Company adopted this standard as of January 1, 2021 on a prospective basis and there was no material impact on its condensed consolidated financial statements and disclosures as a result of the adoption.

Net Loss Per Share Attributable to Common Stockholders (Tables)

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Loss per Share

The following table sets forth the computation of the basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share data):

	Three Months Ended March 31,
	2021			2020
Numerator:
Net loss	$	(14,185	)	$	(5,454	)
Less: cumulative preferred dividends allocated to preferred stockholders		—			(1,983	)
Net loss attributable to common stockholders	$	(14,185	)	$	(7,437	)
Denominator:
Weighted-average shares of common stock outstanding		40,055,435			3,143,159
Net loss per share attributable to common stockholders, basic and diluted	$	(0.35	)	$	(2.37	)

Summary of Outstanding Potentially Dilutive Securities Were Excluded from Computation of Diluted Net Loss Per Share

	March 31,
	2021		2020
Convertible preferred stock		—		21,369,774
Warrants to purchase convertible preferred stock		—		61,292
Common stock subject to repurchase		—		17,297
Options issued and outstanding		4,350,467		3,200,872
Estimated common stock issuable under the employee stock purchase plan		1,600		—
Total		4,352,067		24,649,235

Condensed Consolidated Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Related-party revenue		$ 655
Type of Revenue [Extensible List]	alxo:RelatedPartyMember	alxo:RelatedPartyMember
Operating expenses:
Research and development	$ 9,849	$ 3,828
General and administrative	4,359	1,473
Cost of services for related-party revenue		596
Total operating expenses	14,208	5,897
Loss from operations	(14,208)	(5,242)
Interest expense	(3)	(215)
Other income, net	26	7
Loss before income taxes	(14,185)	(5,450)
Income tax provision		(4)
Net loss and comprehensive loss	(14,185)	(5,454)
Cumulative dividends allocated to preferred stockholders		(1,983)
Net loss attributable to common stockholders	$ (14,185)	$ (7,437)
Net loss per share attributable to common stockholders, basic and diluted	$ (0.35)	$ (2.37)
Weighted-average shares of common stock used to compute net loss per share attributable to common stockholders, basic and diluted	40,055,435	3,143,159

Organization

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

ORGANIZATION

(1) ORGANIZATION

Organization

ALX Oncology Holdings Inc., or the Company, is a clinical-stage immuno-oncology company focused on helping patients fight cancer by developing therapies that block the CD47 checkpoint pathway and bridge the innate and adaptive immune system. The Company was formed as a Delaware corporation on April 1, 2020, or Inception, for the purpose of completing the Company’s initial public offering of its common stock and related transactions in order to carry on the business of ALX Oncology Limited. After Inception, ALX Oncology Limited became a wholly-owned subsidiary of the Company as a result of the internal reorganization. As part of the internal reorganization, all of the equity, option and warrant holders of ALX Oncology Limited became equity, option and warrant holders of the Company, holding the same number of corresponding shares, options and/or warrants in the Company as they did in ALX Oncology Limited immediately prior to the internal reorganization. The information included herein is presented as that of ALX Oncology Holdings Inc. unless such information refers to a date prior to April 1, 2020, in which case it will reflect that of ALX Oncology Limited, the predecessor company.

The Company owns subsidiaries, consisting of ALX Oncology Limited, incorporated in Ireland; ALX Oncology Inc., incorporated in the United States, and Alexo International Holdings Ltd, incorporated in Malta; Alexo Therapeutics International, incorporated in the Cayman Islands, which is a wholly-owned subsidiary of Alexo International Holdings Ltd. and Sirpant Therapeutics, incorporated in the Cayman Islands, which is a wholly-owned subsidiary of Alexo Therapeutics International, or collectively, the Subsidiaries.

As of March 31, 2021, the Company has devoted substantially all of its efforts to the formation and financing of the Company, as well as product development, and has not realized product revenues from its planned principal operations. The Company has no manufacturing facilities and all manufacturing related activities are contracted out to third-party service providers.

Management expects to incur additional losses in the future to conduct product candidate research and development and to conduct pre-commercialization activities and recognizes that the Company will likely raise additional capital to fully implement its business plan. The Company intends to raise such capital through the sale of additional equity, debt financings or strategic alliances with third parties. However, there can be no assurance that the Company will be successful in acquiring additional funding at levels sufficient to fund its operations or on terms acceptable to the Company. If the Company is unsuccessful in its efforts to raise additional financing, the Company could be required to significantly reduce operating expenses and delay, reduce the scope of or eliminate some of its development programs or its future commercialization efforts, out-license intellectual property rights to its product candidates and sell unsecured assets, or a combination of the above, any of which may have a material adverse effect on the Company’s business, results of operations, financial condition and/or its ability to fund its scheduled obligations on a timely basis or at all. The Company believes that the existing capital resources will be sufficient to fund the projected operating requirements for at least the next twelve months.

Related-Party Transactions - Additional Information (Details) $ in Thousands		1 Months Ended	3 Months Ended
	Jul. 01, 2020	Jun. 30, 2018	Mar. 31, 2021 USD ($) Investor	Mar. 31, 2020 USD ($)
Related Party Transaction [Line Items]
Related-party revenue				$ 655
Research and development costs			$ 9,849	3,828
Research and Development Services Agreement \| Tollnine
Related Party Transaction [Line Items]
Number of company's investors who are investors in related party as well \| Investor			2
Related-party revenue			$ 0	$ 700
Initial term of agreement with related party		3 years
Markup cost in percentage		10.00%
Research and Development Services Agreement \| Tallac Therapeutics
Related Party Transaction [Line Items]
Initial term of agreement with related party	4 years
Agreement automatically renewal additional term unless terminated	1 year
Markup cost in percentage	10.00%
Research and development costs			$ 400

Term Loan

3 Months Ended

Mar. 31, 2021

Debt Disclosure [Abstract]

TERM LOAN AND RELATED DERIVATIVES

(6) TERM LOAN AND RELATED DERIVATIVES

The Company’s wholly-owned subsidiaries Alexo Therapeutics International and Sirpant Therapeutics, as borrowers, entered into a Loan and Security Agreement, or the Loan Agreement, dated as of December 20, 2019, with Silicon Valley Bank, or SVB, and WestRiver, collectively as lenders, and SVB, as administrative agent and collateral agent. On the closing date of the Loan Agreement in December 2019, $6.0 million was funded to the Company. In December 2020, the Company repaid the loan balance.

In conjunction with the Loan Agreement, the Company issued warrants to purchase Series B convertible preferred stock to SVB and WestRiver, and recorded a warrant liability of approximately $0.4 million at the date of issuance. The Company also determined that certain loan features were embedded derivatives requiring bifurcation and separate accounting, and recorded a term loan compound derivative liability of approximately $51,000. The Company measured its Series B convertible preferred stock warrant liability and term loan compound derivative liability at fair value on a recurring basis, which were classified as Level 3 liabilities. During the three months ended March 31, 2020, the increases in fair value in warrant liability and compound derivative liability were approximately $86,000 and $14,000, respectively, which were recognized as a component of other income, net in the condensed consolidated statement of operations and comprehensive loss. The Company reclassified the preferred stock warrant liability balance into additional paid-in capital in July 2020 with no further re-measurement required, as the common stock warrants are considered permanent equity effective with the completion of the initial public offering. The compound derivative liability was extinguished upon the extinguishment of the host instrument in December 2020.

Significant Accounting Policies

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

SIGNIFICANT ACCOUNTING POLICIES

(2) SIGNIFICANT ACCOUNTING POLICIES

Basis of Preparation

All intercompany balances and transactions have been eliminated in consolidation.

Reverse Stock Split

Use of Estimates

Significant Accounting Policies

Leases

Adopted Accounting Pronouncements

(i)

not to reassess prior conclusions on whether any expired or existing contracts are or contain a lease, lease classification, and initial direct costs;

(ii)

combine lease and non-lease components

(iii)

not to recognize ROU assets or lease liabilities for short term leases

License Agreement

3 Months Ended

Mar. 31, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

LICENSE AGREEMENT

(9) LICENSE AGREEMENT

Exclusive (Equity) Agreement with The Board of Trustees of the Leland Stanford Junior University

In March 2015, the Company entered into a license agreement, or the Stanford Agreement, with the Board of Trustees of the Leland Stanford Junior University, or Stanford, under which the Company obtained a worldwide, royalty-bearing, sublicensable license under certain patents relating to the Company’s current product candidates, to develop, manufacture and commercialize products for use in certain licensed fields, the scope of which would include the application of the licensed intellectual property in oncology. The license granted to the Company in the Stanford Agreement includes an exclusive grant, subject to certain pre-existing non-exclusive or exclusive rights that Stanford retained for grant to third parties with respect to certain categories of the licensed patents in certain fields of use and retained rights by Stanford and all other nonprofit institutions to use and practice the licensed patents and technology for internal research and other nonprofit purposes. The license granted to the Company in the Stanford Agreement also includes non-exclusive grants to certain Stanford patents.

In consideration for the rights granted to the Company under the Stanford Agreement, the Company paid Stanford a nonrefundable license royalty and reimbursed Stanford for past patent expenses, together totaling less than $0.1 million, and granted Stanford a specified number of shares of common stock of the Company. In addition, the Company is obligated to pay Stanford ongoing patent expenses and an annual license maintenance fee, which are nominal and will be creditable against any royalties payable to Stanford in the applicable year. The Company is required to make milestone payments up to an aggregate of $5.0 million in respect of a specified number of licensed products that successfully satisfy certain clinical and regulatory milestones. No milestone payments have been made through March 31, 2021. The Company also agreed to pay Stanford tiered royalties on a specified percentage of net sales made by the Company, its affiliates and its sublicensees of licensed products at rates ranging within low single-digit percentages, subject to certain reductions and offsets. The license, on a licensed product-by-licensed product and country-by-country basis, shall become royalty-free and fully paid-up upon the later of the date on which the last valid claim included in the exclusively or non-exclusively licensed patents expires and ten years after the first commercial sale of the licensed product in such country.

The Company may terminate the Stanford Agreement, on a licensed product-by-licensed product basis, at any time for any reason by providing at least 60 days’ written notice to Stanford. Stanford may terminate the Stanford Agreement, if the Company is in breach of any provision of the Stanford Agreement and fails to remedy such breach within 60 days after written notice of such breach by Stanford. In addition, Stanford has the right to terminate the Stanford Agreement, on a licensed product-by-licensed product basis, if the Company is not diligently developing and commercializing such licensed product under certain conditions or if the Company fails to achieve specified development milestones for such licensed product by certain dates, subject to the Company’s extension rights.

Commercial License Agreement with Selexis SA

In June 2016, the Company entered into a license agreement with Selexis SA, or Selexis, under which the Company obtained a worldwide, royalty-bearing, sublicensable license under certain patents, know-how and other intellectual property, to use Selexis generated cell lines to manufacture ALX148 and to make, use and sell licensed product containing such compound in all fields of use. The rights granted under this agreement include the rights to grant sublicenses to contractors or other collaboration partners, in each case to develop production processes or manufacture licensed product containing ALX148.

In consideration for the rights granted to the Company under the agreement, the Company paid Selexis a nominal one-time fee and will pay Selexis an annual maintenance fee. The Company also agreed to pay Selexis milestone payments up to an aggregate of 1.2 million Swiss Francs in respect of all licensed products developed and/or commercialized under the grant that successfully satisfies certain milestone events. The Company also agreed to pay Selexis a flat royalty of a very low single-digit percentage on net sales made by the Company, its affiliates and sublicensees of products. This royalty obligation, on a product-by-product and country-by-country basis, shall terminate and become fully paid-up upon the passing of ten years after the first commercial sale of the product in such country, or the Company’s exercise of the royalty buyout option exercisable at any time prior to the first commercial sale of a licensed product.

The Company may terminate the license agreement at any time for any reason with at least 60 days’ written notice to Selexis. Either party may terminate the license agreement if the other party enters into a bankruptcy event or in the event of a material breach of the agreement (that cannot be cured or remains uncured for 60 days after the date that the defaulting party is provided with written notice of such breach). The Company’s obligations to pay royalties that are accrued or accruable will survive any termination of the agreement, and in certain circumstances the licenses granted under the agreement will terminate unless they have become fully paid up as described in the previous paragraph.

Commercial Antibody Agreement with Crystal Bioscience Inc. (Now a Subsidiary of Ligand Pharmaceuticals Incorporated)

In March 2017, the Company entered into an agreement with Crystal Bioscience Inc. (now a subsidiary of Ligand Pharmaceuticals Incorporated), or Crystal, under which the Company obtained an assignment of certain patents, covering certain SIRPα antibodies. Under this agreement, the Company also received a worldwide, royalty-bearing non-exclusive license, with the right to grant sublicenses through multiple tiers of sublicenses, under certain of Crystal’s background patents and know-how necessary to commercialize the rights under the assigned patents.

In consideration for the rights granted to the Company under the agreement, it agreed to pay Crystal milestone payments up to $11.1 million in respect of all licensed products developed under the assigned patents, that successfully satisfy certain clinical and regulatory milestones, each milestone being paid only once for all products. The Company also agreed to pay Crystal tiered royalties on net sales made by the Company, its affiliates and sublicensees of products at rates ranging within low single-digit percentages, subject to certain potential reductions. This royalty obligation, on a product-by-product and country-by-country basis, shall terminate and become fully paid-up upon the later of the date on which the last valid claim included in the licensed patents expires and ten years after the first commercial sale of the product in such country.

The Company agreed to use commercially reasonable efforts to develop and commercialize licensed products, including meeting defined development milestones by certain specified dates.

The Company may terminate the agreement at any time for any reason with at least 60 days’ written notice to Crystal. Either party may terminate the agreement if the other party enters into a bankruptcy event or in the event of material breach of the agreement (that remains uncured for 60 days after the date that it is provided with written notice of such breach). The Company’s obligations to pay royalties and milestone payments which accrued pre-termination or accrue post-termination will survive any termination.

Fair Value of Financial Instruments

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

FAIR VALUE OF FINANCIAL INSTRUMENTS

(3) FAIR VALUE OF FINANCIAL INSTRUMENTS

The fair value of the Company’s financial assets and liabilities are determined in accordance with the fair value hierarchy established in Accounting Standards Codification (ASC) Topic 820, Fair Value Measurements and Disclosures. ASC Topic 820 defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The fair value hierarchy of ASC Topic 820 requires an entity to maximize the use of observable inputs when measuring fair value and classifies those inputs into three levels:

Level 1—Observable inputs, such as quoted prices in active markets

Level 2—Inputs, other than the quoted prices in active markets, which 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 instrument’s anticipated life

Level 3—Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions

Cash and cash equivalents are reported at their respective fair values on the Company’s condensed consolidated balance sheets. Where quoted prices are available in an active market, securities are classified as Level 1. The Company classifies money market funds as Level 1. If quoted market prices are not available for the specific security, then the Company would estimate fair value by using quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant inputs are observable in the market or can be corroborated by observable market data for substantially the full term of the assets. Where applicable, these models project future cash flows and discount the future amounts to a present value using market-based observable inputs obtained from various third-party data providers, including but not limited to benchmark yields, reported trades and broker/dealer quotes. Where applicable, the market approach utilizes prices and information from market transactions for similar or identical assets.

The following table sets forth the Company’s financial assets that are measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands):

	As of March 31, 2021
	Level 1		Level 2		Level 3		Fair Value
Financial assets
Cash equivalents
Money market funds	$	415,129	$	—	$	—	$	415,129

	As of December 31, 2020
	Level 1		Level 2		Level 3		Fair Value
Financial assets
Cash equivalents
Money market funds	$	424,115	$	—	$	—	$	424,115

The Company did not have any outstanding financial liabilities to be re-measured on a recurring basis as of March 31, 2021 and December 31, 2020.

There were no transfers of assets or liabilities between the fair value measurement levels during the three months ended March 31, 2021 and 2020, respectively.

The carrying values of the Company’s financial instruments, such as accounts payable and accrued expenses and other current liabilities, approximated fair value due to the short-term nature of these items.

- Definition

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

+ References + Details

License Agreement - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)
Exclusive Equity Agreement \| Stanford Junior University
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Nonrefundable license royalty and patent expenses	$ 0.1
Clinical and regulatory milestones payments	$ 5.0
Agreement expiry description	licensed patents expires and ten years after the first commercial sale of the licensed product in such country
Termination of agreement written notice period	60 days
Notice period to remedy the breach of agreement	60 days
Commercial License Agreement \| Selexis SA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Clinical and regulatory milestones payments	$ 1.2
Agreement expiry description	shall terminate and become fully paid-up upon the passing of ten years after the first commercial sale of the product in such country, or the Company’s exercise of the royalty buyout option exercisable at any time prior to the first commercial sale of a licensed product
Termination of agreement written notice period	60 days
Notice period to remedy the breach of agreement	60 days
Commercial Antibody Agreement \| Crystal Bioscience Inc
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Clinical and regulatory milestones payments	$ 11.1
Agreement expiry description	licensed patents expires and ten years after the first commercial sale of the product in such country
Termination of agreement written notice period	60 days
Notice period to remedy the breach of agreement	60 days

Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net loss	$ (14,185)	$ (5,454)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5	113
Non-cash lease costs	58
Stock-based compensation	1,800	151
Amortization of term loan discount and issuance costs		108
Changes in fair value of compound derivative liability and warrants		100
Changes in operating assets and liabilities
Receivables due from related-party		(655)
Prepaid expenses and other current assets	(453)	(931)
Other assets	(583)	7
Accounts payable	7,346	(1,761)
Accrued expenses and other current liabilities	585	(614)
Other non-current liabilities	292	(27)
Net cash used in operating activities	(5,135)	(8,963)
Investing activities
Purchase of property and equipment	(7)	(10)
Net cash used in investing activities	(7)	(10)
Financing activities
Proceeds from exercise of common stock under equity incentive plans	778
Proceeds from issuance of convertible preferred stock, net		104,991
Net cash provided by financing activities	778	104,991
Net increase (decrease) in cash and cash equivalents	(4,364)	96,018
Cash and cash equivalents at beginning of period	434,219	9,017
Cash and cash equivalents at end of period	429,855	105,035
Supplemental disclosure
Cash paid for interest		81
Supplemental disclosure of non-cash investing and financing activities
Vesting of early exercised stock options		16
Unpaid convertible preferred stock issuance costs		311
Unpaid deferred offering costs		$ 229
Receivables for cash in-transit on exercise of common stock under equity incentive plans	$ 246

Fair Value of Financial Instruments - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair value assets transferred from level 1 to level 2	$ 0	$ 0
Fair value assets transferred from level 2 to level 1	0	0
Fair value liabilities transferred from level 1 to level 2	0	0
Fair value liabilities transferred from level 2 to level 1	0	0
Fair value assets transferred into level 3	0	0
Fair value assets transferred out of level 3	0	0
Fair value liabilities transferred into level 3	0	0
Fair value liabilities transferred out of level 3	$ 0	$ 0

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Total Stock Based Compensation Expense

Total stock-based compensation expense recognized in the condensed consolidated statements of operations and comprehensive loss was as follows (in thousands):

	Three Months Ended March 31,
	2021		2020
Research and development	$	579	$	83
General and administrative		1,221		68
	$	1,800	$	151

Commitments and Contingencies - Additional Information (Details) - Master Service Agreement $ in Millions	1 Months Ended
	Nov. 30, 2015 USD ($)
Commitments And Contingencies [Line Items]
Initial term of agreement	3 years
Renewal periods of agreement	1 year
Future purchase obligations	$ 7.5
Two Drug Product Manufacturer
Commitments And Contingencies [Line Items]
Future purchase obligations	$ 1.8

Commitments and Contingencies

3 Months Ended

Mar. 31, 2021

Commitments And Contingencies Disclosure [Abstract]

COMMITMENTS AND CONTINGENCIES

(12) COMMITMENTS AND CONTINGENCIES

Guarantees and Indemnifications

In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future but have not yet been made. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. However, the Company may record charges in the future as a result of these indemnification obligations. The Company also has indemnification obligations to its officers and directors for specified events or occurrences, subject to some limits, while they are serving at the Company’s request in such capacities. There have been no claims to date and the Company has director and officer insurance that may enable the Company to recover a portion of any amounts paid for future potential claims. The Company believes the fair value of these indemnification agreements is minimal. Accordingly, the Company has not recorded any liabilities for these agreements as of March 31, 2021.

Contingencies

From time to time, the Company may be a party to various claims in the normal course of business. Legal fees and other costs associated with such actions will be expensed as incurred. The Company will assess, in conjunction with its legal counsel, the need to record a liability for litigation and contingencies. Reserve estimates will be recorded when and if it is determined that a loss related matter is both probable and reasonably estimable. For the three months ended March 31, 2021 the Company had no pending or threatened litigation.

Leases

The Company has an operating lease related to its office space in Burlingame, California and embedded finance leases related to a pharmaceutical support services agreement. See Note 5 "Leases" for details of related commitments.

Other Contractual Obligations and Other Commitments

In November 2015, the Company entered into a Master Service Agreement, or the MSA, with KBI Biopharma, Inc. relating to formulation development, process development and cGMP manufacturing of ALX148 for use in clinical trials on a project basis. The MSA had an initial term of three years with successive one-year renewal periods, is cancellable upon notice and is non-exclusive. Statements of work under the MSA commit the Company to certain future purchase obligations of approximately $7.5 million. In addition, the Company has commitments with two other drug product manufacturers that commit the Company to certain future purchase obligations of approximately $1.8 million. The Company expects to make payments for these commitments through 2025 based on non-cancellable commitments and forecasts that include estimates of future market demand, quantity discounts and manufacturing efficiencies that may impact timing of purchases.

The Company enters into contracts in the normal course of business with various third parties for clinical trials, preclinical research studies and testing, manufacturing and other services and products for operating purposes. These contracts generally provide for termination upon notice. Payments due upon cancellation consist only of payments for services provided or expenses incurred, including non-cancellable obligations of our service providers, up to the date of cancellation.

Leases - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
Leases - Additional Information (Details) - USD ($)	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2017
Lessee Lease Description [Line Items]
Option to extend term	no
Operating lease ROU assets	$ 300,000
Finance lease ROU assets	200,000
Finance leases not yet commenced, lease obligations	$ 800,000
Finance leases not yet commenced, expiration year	2023
Master Service Agreement
Lessee Lease Description [Line Items]
Amortization of finance ROU and interest expense	$ 23,000
Cash paid for finance lease	0
Cash paid for interest on finance lease	0
Office Space
Lessee Lease Description [Line Items]
Lessee, operating lease term of contract			5 years 4 months
Lessee, operating lease commencing end date			May 31, 2023
Operating lease cost	58,000
Variable lease cost	22,000
Operating leases, cash paid	$ 23,000
Rent expense		$ 200,000

Stockholders' Equity - Additional Information (Details) - shares	Mar. 31, 2021	Dec. 31, 2020	Jul. 21, 2020
Class Of Stock [Line Items]
Common stock, shares authorized	1,000,000,000	1,000,000,000	1,000,000,000
Common stock, shares outstanding	40,208,569	39,844,522
Undesignated Preferred Stock
Class Of Stock [Line Items]
Convertible preferred stock, shares authorized			100,000,000