0001171843-23-006912 | 10-Q | XBRL Viewer

Note 3 - Fair Value Measurements

9 Months Ended

Sep. 30, 2023

3. Fair Value Measurements

The following tables represent the Company’s financial assets that are measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands):

	Fair Value Measurements as of September 30, 2023 Using:
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
Assets
Corporate bonds	$	—	$	41,633	$	—	$	41,633
Commercial paper		48,889		—		—		48,889
Certificates of deposit		—		19,547		—		19,547
U.S. government treasuries		14,782		—		—		14,782
Asset-backed securities		—		8,426		—		8,426
Total assets	$	63,671	$	69,606	$	—	$	133,277

	Fair Value Measurements as of December 31, 2022 Using:
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
Assets
Corporate bonds	$	—	$	87,760	$	—	$	87,760
Commercial paper		37,682		—		—		37,682
Certificates of deposit		—		19,667		—		19,667
Asset-backed securities		—		6,554		—		6,554
Cash equivalents		9,438		—		—		9,438
Total assets	$	47,120	$	113,981	$	—	$	161,101

- 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

Note 8 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions		9 Months Ended
	Jan. 01, 2023	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2020
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 15,800
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 2.82	$ 2.30
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value		$ 34	$ 19
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 10,400
The 2020 Stock Option and Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized				2.9
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	5.1
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		5.1
Restricted Stock [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 100
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		3 months 18 days
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 9 months 18 days
Share-Based Payment Arrangement, Option [Member] \| The 2020 Stock Option and Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 5,400
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 9 months 18 days

Note 5 - Property and Equipment

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Property, Plant and Equipment Disclosure [Text Block]

5. Property and Equipment

Property and equipment consist of the following (in thousands):

	September 30, 2023			December 31, 2022
Equipment	$	5,158		$	5,137
Leasehold improvements		1,612			1,612
Software		364			364
Furniture and fixtures		22			22
Total property and equipment–at cost		7,156			7,135
Less: Accumulated depreciation		(6,105	)		(5,568	)
Property and equipment, net	$	1,051		$	1,567

Depreciation and amortization expense for the nine months ended September 30, 2023 and 2022 was $0.5 million and $0.6 million respectively.

Note 2 - Summary of Significant Accounting Policies	9 Months Ended
Sep. 30, 2023
Notes to Financial Statements
Significant Accounting Policies [Text Block]	2. Summary of Significant Accounting Policies There have been no material changes to the significant accounting policies previously disclosed in the Company’s Annual Report.

Note 2 - Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Significant Accounting Policies [Text Block]

2. Summary of Significant Accounting Policies

There have been no material changes to the significant accounting policies previously disclosed in the Company’s Annual Report.

Note 8 - Stock-based Compensation - Summary of Restricted Stock Activity (Details) - Restricted Stock [Member] shares in Thousands	9 Months Ended
	Sep. 30, 2023 $ / shares shares
Unvested, shares (in shares) \| shares	193
Unvested, fair value per share (in dollars per share) \| $ / shares	$ 1.74
Granted, shares (in shares) \| shares	0
Granted, fair value per share (in dollars per share) \| $ / shares	$ 0
Vested, shares (in shares) \| shares	(162)
Vested, fair value per share (in dollars per share) \| $ / shares	$ 1.72
Forfeited or canceled, shares (in shares) \| shares	0
Forfeited or canceled, fair value per share (in dollars per share) \| $ / shares	$ 0
Unvested, shares (in shares) \| shares	31
Unvested, fair value per share (in dollars per share) \| $ / shares	$ 1.82

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (Parentheticals) $ in Millions	3 Months Ended
	Jun. 30, 2023 USD ($)
Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs	$ 0.1

Note 4 - Marketable Securities

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

4. Marketable Securities

The objectives of the Company’s investment policy are to ensure the safety and preservation of invested funds, as well as to maintain liquidity sufficient to meet cash flow requirements. The Company invests its excess cash in securities issued by financial institutions, commercial companies, and government agencies that management believes to be of high credit quality in order to limit the amount of its credit exposure. The Company has not realized any net losses from its investments.

Unrealized gains and losses on investments that are available for sale are recognized in accumulated other comprehensive loss, unless an unrealized loss is considered to be other than temporary, in which case the unrealized loss is charged to operations. The Company periodically reviews its investments for other than temporary declines in fair value below cost basis and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.

The Company believes the individual unrealized losses represent temporary declines primarily resulting from interest rate changes. Realized gains and losses are included in other income in the condensed consolidated statements of operations and comprehensive loss and are determined using the specific identification method with transactions recorded on a trade date basis. The Company classifies marketable securities that are available for use in current operations as current assets on the condensed consolidated balance sheet.

The following tables summarize marketable securities held (in thousands):

	As of September 30, 2023
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	41,850	$	5	$	(222	)	$	41,633
Commercial paper		48,912		—		(23	)		48,889
Certificates of deposit		19,557		2		(12	)		19,547
U.S. government treasuries		14,935		—		(153	)		14,782
Asset-backed securities		8,453		—		(27	)		8,426
Total assets	$	133,707	$	7	$	(437	)	$	133,277

	As of December 31, 2022
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	87,998	$	12	$	(250	)	$	87,760
Commercial paper		37,680		33		(31	)		37,682
Certificates of deposit		19,689		16		(38	)		19,667
Asset-backed securities		6,598		3		(47	)		6,554
Total assets	$	151,965	$	64	$	(366	)	$	151,663

	As of
	September 30, 2023		December 31, 2022
Maturing in one year or less	$	97,216	$	134,620
Maturing after one year through two years		36,061		17,043
Total	$	133,277	$	151,663

Note 6 - Accrued Expenses

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Accounts Payable and Accrued Liabilities Disclosure [Text Block]

6. Accrued Expenses

Accrued expenses consist of the following (in thousands):

	September 30,		December 31,
	2023		2022
Project expenses	$	3,827	$	10,038
Compensation and benefits		1,426		1,556
Other		391		96
Total accrued expenses	$	5,644	$	11,690

Project expenses consist of $2.9 million of accrued manufacturing expenses and $0.9 million of accrued clinical expenses. Included in accrued manufacturing expenses are $2.1 million of minimum contractual obligations related to CTX-009.

Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares shares in Thousands	Sep. 30, 2023	Dec. 31, 2022
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.0001	$ 0.0001
Common Stock, Shares Authorized (in shares)	300,000	300,000
Common Stock, Shares, Issued (in shares)	127,476	126,495
Common Stock, Shares, Outstanding (in shares)	127,445	126,302

Note 4 - Marketable Securities - Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Maturing in one year or less	$ 97,216	$ 134,620
Maturing after one year through two years	36,061	17,043
Total	$ 133,277	$ 151,663

Note 6 - Accrued Expenses (Details Textual) $ in Millions	Sep. 30, 2023 USD ($)
Accrued Manufacturing Expenses	$ 2.9
Accrued Clinical Expenses	0.9
Manufacture and Purchase of CTX-009 [Member]
Contractual Obligation	$ 2.1

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (29,079)	$ (27,631)
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Depreciation and amortization	538	587
Stock-based compensation	4,520	4,305
Amortization of premium and discount on marketable securities	(2,414)	(190)
ROU asset amortization	884	833
Gain on disposal of equipment	0	(70)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	5,301	639
Accounts payable	(1,076)	1,894
Accrued expenses	(6,046)	(3,033)
Operating lease liability	(892)	(818)
Net cash used in operating activities	(28,264)	(23,484)
Cash flows from investing activities:
Purchases of property and equipment	(21)	(158)
Purchases of marketable securities	(110,339)	(117,332)
Proceeds from sale or maturities of marketable securities	131,011	12,760
Proceeds from sale of equipment	0	176
Net cash provided by (used in) investing activities	20,651	(104,554)
Cash flows from financing activities:
Proceeds from exercise of stock options	62	5
Proceeds from issuance of common stock	(3,126)	0
Issuance costs from issuance of common stock	(95)	0
Net cash provided by financing activities	3,093	5
Net change in cash and cash equivalents	(4,520)	(128,033)
Cash and cash equivalents at beginning of period	34,946	144,514
Cash and cash equivalents at end of period	30,426	16,481
Supplemental disclosure of cash flow information
Unrealized loss on marketable securities	$ 128	$ 641

Note 9 - Related Parties and Related-Party Transactions

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

9. Related Parties and Related-Party Transactions

There were no material related party transactions during the nine months ended September 30, 2023 and 2022.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

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+ Details

Note 5 - Property and Equipment (Details Textual) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Depreciation	$ 0.5	$ 0.6

Note 6 - Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Project expenses	$ 3,827	$ 10,038
Compensation and benefits	1,426	1,556
Other	391	96
Total accrued expenses	$ 5,644	$ 11,690

Document And Entity Information - shares	9 Months Ended
Document And Entity Information - shares	Sep. 30, 2023	Nov. 03, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-39696
Entity Registrant Name	COMPASS THERAPEUTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-4876496
Entity Address, Address Line One	80 Guest St., Suite 601
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02135
City Area Code	617
Local Phone Number	500-8099
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	CMPX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		127,486,326
Entity Central Index Key	0001738021
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Amendment Flag	false

Note 6 - Accrued Expenses (Tables)

9 Months Ended

Sep. 30, 2023

Notes Tables

Schedule of Accrued Liabilities [Table Text Block]

	September 30,		December 31,
	2023		2022
Project expenses	$	3,827	$	10,038
Compensation and benefits		1,426		1,556
Other		391		96
Total accrued expenses	$	5,644	$	11,690

Note 8 - Stock-based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Stock-based compensation expense	$ 1,625	$ 1,287	$ 4,520	$ 4,305
Research and Development Expense [Member]
Stock-based compensation expense	159	170	387	718
General and Administrative Expense [Member]
Stock-based compensation expense	$ 1,466	$ 1,117	$ 4,133	$ 3,587

Note 10 - Other Income

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Other Nonoperating Income and Expense [Text Block]

10. Other Income

The following table summarizes other income (in thousands):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2023		2022		2023		2022
Interest income	$	1,962	$	623	$	5,891	$	1,066
Realized gain on disposal of equipment		—		—		—		70
Total other income	$	1,962	$	623	$	5,891	$	1,136

Note 12 - Stockholders' Equity

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Equity [Text Block]

12. Stockholders’ Equity

Through September 30, 2023, we sold through our at-the-market (“ATM”) agreement with Jefferies LLC, 951,873 shares of common stock at an average price of $3.28 for total proceeds of $3.1 million and net proceeds of $3.0 million.

- Definition

The entire disclosure for equity.

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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

+ Details

Note 5 - Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Total property and equipment–at cost	$ 7,156	$ 7,135
Less: Accumulated depreciation	(6,105)	(5,568)
Property and equipment, net	1,051	1,567
Equipment [Member]
Total property and equipment–at cost	5,158	5,137
Leasehold Improvements [Member]
Total property and equipment–at cost	1,612	1,612
Software Development [Member]
Total property and equipment–at cost	364	364
Furniture and Fixtures [Member]
Total property and equipment–at cost	$ 22	$ 22

Note 8 - Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2023

Notes Tables

Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	159	$	170	$	387	$	718
General and administrative		1,466		1,117		4,133		3,587
Total	$	1,625	$	1,287	$	4,520	$	4,305

Nonvested Restricted Stock Shares Activity [Table Text Block]

	Shares			Fair Value
Weighted Average Fair Value	(In thousands)			Per Share
Unvested, December 31, 2022		193		$	1.74
Granted		—		$	—
Vested		(162	)	$	1.72
Forfeited or canceled		—		$	—
Unvested, September 30, 2023		31		$	1.82

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

				Weighted		Weighted
	Number of			Average		Average		Aggregate
	Unvested			Exercise		Remaining		Intrinsic
	Options			Price		Contractual		Value
	(000's)			Per Share		Term (In years)		(000's)
Outstanding at December 31, 2022		5,378		$	3.89		8.24	$	6,316
Granted		2,688		$	3.76		9.35
Exercised		(29	)	$	1.75
Forfeited/canceled		(274	)	$	4.29
Outstanding at September 30, 2023		7,763		$	3.84		8.27	$	92
Vested at September 30, 2023		3,580		$	4.28		7.60	$	34

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Nine Months Ended September 30,
	2023			2022
Expected term (in years)		6.0			6.0
Risk-free rate		3.8	%		2.0	%
Expected volatility		88	%		94	%
Expected dividend yield		—			—

Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]

	Shares (000's)		Weighted Average Price Per Share		Weighted Average Fair Value (000's)
Unvested, December 31, 2022		900	$	3.83	$	3,447
Granted		900		3.93		3,537
Vested		—		—		—
Forfeited or canceled		—		—		—
Unvested, September 30, 2023		1,800	$	3.88	$	6,984

Note 10 - Other Income (Tables)

9 Months Ended

Sep. 30, 2023

Notes Tables

Schedule of Other Nonoperating Income (Expense) [Table Text Block]

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2023		2022		2023		2022
Interest income	$	1,962	$	623	$	5,891	$	1,066
Realized gain on disposal of equipment		—		—		—		70
Total other income	$	1,962	$	623	$	5,891	$	1,136

Note 8 - Stock-based Compensation

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Share-Based Payment Arrangement [Text Block]

8. Stock-Based Compensation

Stock-based compensation expense for the three and nine months ended September 30, 2023 and 2022 was classified in the condensed consolidated statement of operations as follows (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	159	$	170	$	387	$	718
General and administrative		1,466		1,117		4,133		3,587
Total	$	1,625	$	1,287	$	4,520	$	4,305

As of September 30, 2023, the remaining unrecognized stock-based compensation cost from all plans to be recognized in future periods totaled $15.8 million.

Restricted Stock:

Prior to the adoption of the 2020 Plan, the Company issued restricted stock. A summary of the Company’s restricted stock activity during the nine months ended September 30, 2023 is as follows:

	Shares			Fair Value
Weighted Average Fair Value	(In thousands)			Per Share
Unvested, December 31, 2022		193		$	1.74
Granted		—		$	—
Vested		(162	)	$	1.72
Forfeited or canceled		—		$	—
Unvested, September 30, 2023		31		$	1.82

As of September 30, 2023, the total unrecognized compensation cost related to stock compensation expense for restricted stock is $0.1 million, expected to be recognized over a weighted average period of 0.3 years.

2020 Plan

In June 2020, the Company’s board of directors adopted the 2020 Stock Option and Incentive Plan (the “2020 Plan”) and reserved 2.9 million shares of common stock for issuance under this plan. The 2020 Plan includes automatic annual increases. The increase on January 1, 2023 was 5.1 million shares. As of September 30, 2023, 5.1 million shares remain available for grant.

The 2020 Plan authorizes the board of directors or a committee of the board to grant incentive stock options, nonqualified stock options, restricted stock awards and restricted stock units ("RSUs") to eligible officers, employees, consultants and directors of the Company. Options generally vest over a period of four years and have a contractual life of ten years from the date of grant.

Stock Options:

The following table summarizes the stock option activity for the 2020 Plan:

				Weighted		Weighted
	Number of			Average		Average		Aggregate
	Unvested			Exercise		Remaining		Intrinsic
	Options			Price		Contractual		Value
	(000's)			Per Share		Term (In years)		(000's)
Outstanding at December 31, 2022		5,378		$	3.89		8.24	$	6,316
Granted		2,688		$	3.76		9.35
Exercised		(29	)	$	1.75
Forfeited/canceled		(274	)	$	4.29
Outstanding at September 30, 2023		7,763		$	3.84		8.27	$	92
Vested at September 30, 2023		3,580		$	4.28		7.60	$	34

For the nine months ended September 30, 2023, the weighted average grant date fair value for options granted was $2.82. The intrinsic value for options vested as of September 30, 2023, was $34 thousand. As of September 30, 2023, the total unrecognized compensation cost related to outstanding options was $10.4 million, to be recognized over a weighted average period of 2.8 years.

For the nine months ended September 30, 2022, the weighted average grant date fair value for options granted was $2.30. The intrinsic value for options vested as of September 30, 2022, was $19 thousand.

The weighted average assumptions used in the Black-Scholes pricing model to determine the fair value of stock options granted during the nine months ended September 30, 2023 and 2022 were as follows:

	Nine Months Ended September 30,
	2023			2022
Expected term (in years)		6.0			6.0
Risk-free rate		3.8	%		2.0	%
Expected volatility		88	%		94	%
Expected dividend yield		—			—

As of January 2023, the Company used the historical price of only its own stock to determine the expected volatility. Prior to this, a group of industry peers including the Company’s stock price was used.

RSUs:

The following table summarizes the RSU activity for the 2020 Plan:

	Shares (000's)		Weighted Average Price Per Share		Weighted Average Fair Value (000's)
Unvested, December 31, 2022		900	$	3.83	$	3,447
Granted		900		3.93		3,537
Vested		—		—		—
Forfeited or canceled		—		—		—
Unvested, September 30, 2023		1,800	$	3.88	$	6,984

The weighted average price per share is the weighted grant price based on the closing market price of each of the stock grants. The weighted average fair value is the weighted average share price times the number of shares.

As of September 30, 2023, the remaining unrecognized compensation cost related to RSUs to be recognized in future periods totaled $5.4 million, which is expected to be recognized over a weighted average period of 2.8 years.

Note 1 - Nature of Business and Basis of Presentation

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Business Description and Basis of Presentation [Text Block]

1. Nature of Business and Basis of Presentation

Compass Therapeutics, Inc. (“Compass” or the “Company”) is a clinical-stage, oncology-focused biopharmaceutical company developing proprietary antibody-based therapeutics to treat multiple human diseases. Our scientific focus is on the relationship between angiogenesis and the immune system. Our pipeline includes novel product candidates that leverage our understanding of the tumor microenvironment, including both angiogenesis-targeted agents and immune-oncology focused agents. These product candidates are designed to optimize critical components required for an effective anti-tumor response to cancer. These include modulation of the microvasculature via angiogenesis-targeted agents; induction of a potent immune response via activators on effector cells in the tumor microenvironment; and alleviation of immunosuppressive mechanisms used by tumors to evade immune surveillance. We plan to advance our product candidates through clinical development as both standalone therapies and in combination with our proprietary product candidates as long as their continued development is supported by clinical and nonclinical data. References to Compass or the Company herein include Compass Therapeutics, Inc. and its wholly-owned subsidiaries. The Company was incorporated as Olivia Ventures, Inc. (“Olivia”) in the State of Delaware on March 20, 2018. Prior to the Company’s reverse merger with Compass Therapeutics LLC (the “Merger”), Olivia was a “shell company” (as defined in Rule 12b-2 of the Securities Exchange Act of 1934, as amended).

The Company is subject to risks and uncertainties common to companies in the biotechnology and pharmaceutical industries. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s technology will be obtained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees and consultants.

In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all normal and recurring adjustments (which consist primarily of accruals, estimates and assumptions that impact the financial statements) considered necessary to present fairly the Company’s consolidated financial position as of September 30, 2023 and its consolidated results of operations, comprehensive loss and changes in stockholders’ equity for the three and nine months ended September 30, 2023 and 2022 and cash flows for the nine months ended September 30, 2023 and 2022. Operating results for the three and nine months ended September 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023.

The unaudited condensed consolidated financial statements include the accounts of Compass Therapeutics, Inc. and its subsidiaries, and have been prepared by the Company in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The condensed consolidated balance sheet at December 31, 2022 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by GAAP for complete financial statements. Accordingly, these condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (the “Annual Report”).

Liquidity

Since our inception, we have devoted substantially all of our efforts to organizing and staffing our Company, business planning, raising capital, research and development activities, building our intellectual property portfolio and providing general and administrative support for these operations. We have funded our operations with proceeds from the sale of our equity securities and borrowing from debt arrangements. Through September 30, 2023, we have received $412 million in gross proceeds from the sale of equity securities. As of September 30, 2023, we had cash, cash equivalents and marketable securities of $164 million. Based on our research and development plans, we expect that such cash resources will enable us to fund our operating expenses and capital expenditure requirements into 2026.

COVID-19 Update

We continue to monitor the COVID-19 pandemic and its potential impact on our business. There have been delays in sourcing of selected supplies required for the manufacturing of material to be used in our clinical trials, and these delays have impacted and may impact the timing of our future clinical trials. It is possible that COVID-19 may continue to impact the timeline for our ongoing clinical trials and potential future trials. We are continuing to assess the potential impact of the COVID-19 pandemic on our current and future business and operations, including our expenses and clinical trials, as well as on our industry and the healthcare system.

Note 10 - Other Income - Schedule of Other Income (Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Interest income	$ 1,962	$ 623	$ 5,891	$ 1,066
Realized gain on disposal of equipment	0	0	(0)	70
Total other income	$ 1,962	$ 623	$ 5,891	$ 1,136

Note 8 - Stock-based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Outstanding, options (in shares)	5,378
Outstanding, weighted average exercise price (in dollars per share)	$ 3.89
Outstanding, weighted average remaining contractual term (Year)	8 years 3 months 7 days	8 years 2 months 26 days
Outstanding, aggregate intrinsic value	$ 92	$ 6,316
Granted, options (in shares)	2,688
Granted, weighted average exercise price (in dollars per share)	$ 3.76
Granted, weighted average remaining contractual term (Year)	9 years 4 months 6 days
Exercised, options (in shares)	(29)
Exercised, weighted average exercise price (in dollars per share)	$ 1.75
Forfeited/canceled, options (in shares)	(274)
Forfeited/canceled, weighted average exercise price (in dollars per share)	$ 4.29
Outstanding, options (in shares)	7,763	5,378
Outstanding, weighted average exercise price (in dollars per share)	$ 3.84	$ 3.89
Vested, options (in shares)	3,580
Vested, weighted average exercise price (in dollars per share)	$ 4.28
Vested, weighted average remaining contractual term (Year)	7 years 7 months 6 days
Vested, aggregate intrinsic value	$ 34		$ 19

Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 30,426	$ 34,946
Marketable securities	133,277	151,663
Prepaid expenses and other current assets	2,881	8,182
Total current assets	166,584	194,791
Property and equipment, net	1,051	1,567
Operating lease, right-of-use ("ROU") asset	2,083	2,967
Other assets	320	320
Total assets	170,038	199,645
Current liabilities:
Accounts payable	2,306	3,382
Accrued expenses	5,644	11,690
Operating lease obligations, current portion	1,174	1,097
Total current liabilities	9,124	16,169
Operating lease obligations, long-term portion	869	1,838
Total liabilities	9,993	18,007
Commitments and Contingencies
Stockholders' equity:
Common stock, $0.0001 par value: 300,000 shares authorized; 127,476 and 126,495 shares issued at September 30, 2023 and December 31, 2022, respectively; 127,445 and 126,302 shares outstanding at September 30, 2023 and December 31, 2022, respectively	13	13
Additional paid-in-capital	462,355	454,741
Accumulated other comprehensive loss	(430)	(302)
Accumulated deficit	(301,893)	(272,814)
Total stockholders' equity	160,045	181,638
Total liabilities and stockholders' equity	$ 170,038	$ 199,645

Note 8 - Stock-based Compensation - Summary of RSU Activity (Details) - Restricted Stock Units (RSUs) [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Unvested, shares (in shares)	900
Unvested, fair value per share (in dollars per share)	$ 3.83
Unvested, weighted average fair value	$ 6,984	$ 3,447
Granted, shares (in shares)	900
Granted, fair value per share (in dollars per share)	$ 3.93
Granted, weighted average fair value	$ 3,537
Vested, shares (in shares)	0
Vested, fair value per share (in dollars per share)	$ 0
Forfeited or canceled, shares (in shares)	0
Forfeited or canceled, fair value per share (in dollars per share)	$ 0
Unvested, shares (in shares)	1,800
Unvested, fair value per share (in dollars per share)	$ 3.88

Note 4 - Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2023

Notes Tables

Marketable Securities [Table Text Block]

	As of September 30, 2023
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	41,850	$	5	$	(222	)	$	41,633
Commercial paper		48,912		—		(23	)		48,889
Certificates of deposit		19,557		2		(12	)		19,547
U.S. government treasuries		14,935		—		(153	)		14,782
Asset-backed securities		8,453		—		(27	)		8,426
Total assets	$	133,707	$	7	$	(437	)	$	133,277

	As of December 31, 2022
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	87,998	$	12	$	(250	)	$	87,760
Commercial paper		37,680		33		(31	)		37,682
Certificates of deposit		19,689		16		(38	)		19,667
Asset-backed securities		6,598		3		(47	)		6,554
Total assets	$	151,965	$	64	$	(366	)	$	151,663

Investments Classified by Contractual Maturity Date [Table Text Block]

	As of
	September 30, 2023		December 31, 2022
Maturing in one year or less	$	97,216	$	134,620
Maturing after one year through two years		36,061		17,043
Total	$	133,277	$	151,663

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands	Common Stock Outstanding [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2021	100,832
Balance at Dec. 31, 2021	$ 10,000	$ 373,657,000	$ 0	$ (233,589,000)	$ 140,078,000
Vesting of share-based awards (in shares)	73
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	0	1,574,000	0	0	1,574,000
Net loss	0	0	0	(7,162,000)	(7,162,000)
Stock-based compensation	$ 0	1,574,000	0	0	1,574,000
Balance (in shares) at Mar. 31, 2022	100,905
Balance at Mar. 31, 2022	$ 10,000	375,231,000	0	(240,751,000)	134,490,000
Balance (in shares) at Dec. 31, 2021	100,832
Balance at Dec. 31, 2021	$ 10,000	373,657,000	0	(233,589,000)	140,078,000
Unrealized gain (loss) on marketable securities					(641,000)
Net loss					(27,631,000)
Balance (in shares) at Sep. 30, 2022	101,032
Balance at Sep. 30, 2022	$ 10,000	377,967,000	(641,000)	(261,220,000)	116,116,000
Balance (in shares) at Mar. 31, 2022	100,905
Balance at Mar. 31, 2022	$ 10,000	375,231,000	0	(240,751,000)	134,490,000
Vesting of share-based awards (in shares)	63
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	0	1,444,000	0	0	1,444,000
Unrealized gain (loss) on marketable securities	0	0	(512,000)	0	(512,000)
Net loss	0	0	0	(8,494)	(8,494,000)
Stock-based compensation	$ 0	1,444,000	0	0	1,444,000
Balance (in shares) at Jun. 30, 2022	100,968
Balance at Jun. 30, 2022	$ 10,000	376,675,000	(512,000)	(249,245,000)	126,928,000
Vesting of share-based awards (in shares)	62
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	$ 0	1,287,000	0	0	1,287,000
Common stock issued upon exercise of options (in shares)	2
Common stock issued upon exercise of options	$ 0	5,000	0	0	5,000
Unrealized gain (loss) on marketable securities	0	0	(129,000)	0	(129,000)
Net loss	0	0	0	(11,975,000)	(11,975,000)
Stock-based compensation	$ 0	1,287,000	0	0	1,287,000
Balance (in shares) at Sep. 30, 2022	101,032
Balance at Sep. 30, 2022	$ 10,000	377,967,000	(641,000)	(261,220,000)	116,116,000
Balance (in shares) at Dec. 31, 2022	126,302
Balance at Dec. 31, 2022	$ 13,000	454,741,000	(302,000)	(272,814,000)	181,638,000
Vesting of share-based awards (in shares)	61
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	$ 0	1,267,000	0	0	1,267,000
Common stock issued upon exercise of options (in shares)	12
Common stock issued upon exercise of options	$ 0	41,000	0	0	41,000
Unrealized gain (loss) on marketable securities	0	0	156,000	0	156,000
Net loss	0	0	0	(7,837,000)	(7,837,000)
Stock-based compensation	$ 0	1,267,000	0	0	1,267,000
Balance (in shares) at Mar. 31, 2023	126,375
Balance at Mar. 31, 2023	$ 13,000	456,049,000	(146,000)	(280,651,000)	175,265,000
Balance (in shares) at Dec. 31, 2022	126,302
Balance at Dec. 31, 2022	$ 13,000	454,741,000	(302,000)	(272,814,000)	$ 181,638,000
Common stock issued upon exercise of options (in shares)					29
Unrealized gain (loss) on marketable securities					$ (128,000)
Net loss					(29,079,000)
Balance (in shares) at Sep. 30, 2023	127,445
Balance at Sep. 30, 2023	$ 13,000	462,355,000	(430,000)	(301,893,000)	160,045,000
Balance (in shares) at Mar. 31, 2023	126,375
Balance at Mar. 31, 2023	$ 13,000	456,049,000	(146,000)	(280,651,000)	175,265,000
Vesting of share-based awards (in shares)	61
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	0	1,628,000	0	0	1,628,000
Unrealized gain (loss) on marketable securities	0	0	(361,000)	0	(361,000)
Net loss	$ 0	0	0	(11,278,000)	(11,278,000)
Common shares issued, net of issuance costs of $0.1 million (in shares)	952
Common shares issued, net of issuance costs of $0.1 million	$ 0	3,032,000	0	0	3,032,000
Stock-based compensation	$ 0	1,628,000	0	0	1,628,000
Balance (in shares) at Jun. 30, 2023	127,388
Balance at Jun. 30, 2023	$ 13,000	460,709,000	(507,000)	(291,929,000)	168,286,000
Vesting of share-based awards (in shares)	41
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	$ 0	1,625,000	0	0	1,625,000
Common stock issued upon exercise of options (in shares)	16
Common stock issued upon exercise of options	$ 0	21,000	0	0	21,000
Unrealized gain (loss) on marketable securities	0	0	77,000	0	77,000
Net loss	0	0	0	(9,964,000)	(9,964,000)
Stock-based compensation	$ 0	1,625,000	0	0	1,625,000
Balance (in shares) at Sep. 30, 2023	127,445
Balance at Sep. 30, 2023	$ 13,000	$ 462,355,000	$ (430,000)	$ (301,893,000)	$ 160,045,000

Note 3 - Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2023

Notes Tables

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Fair Value Measurements as of September 30, 2023 Using:
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
Assets
Corporate bonds	$	—	$	41,633	$	—	$	41,633
Commercial paper		48,889		—		—		48,889
Certificates of deposit		—		19,547		—		19,547
U.S. government treasuries		14,782		—		—		14,782
Asset-backed securities		—		8,426		—		8,426
Total assets	$	63,671	$	69,606	$	—	$	133,277

	Fair Value Measurements as of December 31, 2022 Using:
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
Assets
Corporate bonds	$	—	$	87,760	$	—	$	87,760
Commercial paper		37,682		—		—		37,682
Certificates of deposit		—		19,667		—		19,667
Asset-backed securities		—		6,554		—		6,554
Cash equivalents		9,438		—		—		9,438
Total assets	$	47,120	$	113,981	$	—	$	161,101

Note 5 - Property and Equipment (Tables)

9 Months Ended

Sep. 30, 2023

Notes Tables

Property, Plant and Equipment [Table Text Block]

	September 30, 2023			December 31, 2022
Equipment	$	5,158		$	5,137
Leasehold improvements		1,612			1,612
Software		364			364
Furniture and fixtures		22			22
Total property and equipment–at cost		7,156			7,135
Less: Accumulated depreciation		(6,105	)		(5,568	)
Property and equipment, net	$	1,051		$	1,567

Note 4 - Marketable Securities - Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Amortized Cost	$ 133,707	$ 151,965
Unrealized gains	7	64
Unrealized Losses	(437)	(366)
Fair Value	133,277	151,663
Marketable Securities	133,277	151,663
Corporate Debt Securities [Member]
Amortized Cost	41,850	87,998
Unrealized gains	5	12
Unrealized Losses	(222)	(250)
Fair Value	41,633	87,760
Marketable Securities	41,633	87,760
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized Cost	48,912	37,680
Unrealized gains	0	33
Unrealized Losses	(23)	(31)
Fair Value	48,889	37,682
Marketable Securities	48,889	37,682
Certificates of Deposit [Member]
Amortized Cost	19,557	19,689
Unrealized gains	2	16
Unrealized Losses	(12)	(38)
Fair Value	19,547	19,667
Marketable Securities	19,547	19,667
Asset-Backed Securities [Member]
Amortized Cost	8,453	6,598
Unrealized gains	0	3
Unrealized Losses	(27)	(47)
Fair Value	8,426	6,554
Marketable Securities	8,426	$ 6,554
US Treasury Securities [Member]
Amortized Cost	14,935
Unrealized gains	0
Unrealized Losses	(153)
Fair Value	14,782
Marketable Securities	$ 14,782

Note 11 - License, Research and Collaboration Agreements

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Collaborative Arrangement Disclosure [Text Block]

11. License, Research and Collaboration Agreements

Collaboration Agreements

ABL Bio Corporation ("ABL Bio") Agreement

In November 2018, the Company and ABL Bio, a South Korean biotechnology company, entered into an exclusive global (excluding South Korea) license agreement which granted the Company a license to CTX-009 (ABL001), ABL Bio’s bispecific antibody targeting DLL4 and VEGF-A. Under the terms of the agreement, the two companies would jointly develop CTX-009, with ABL Bio responsible for development of CTX-009 throughout the end of Phase 1 clinical trials and the Company responsible for the development of CTX-009 from Phase 2 and onward. ABL Bio received a $5 million upfront payment and $6 million development milestone payment. In addition, ABL Bio is eligible to receive up to $96 million of development and regulatory milestone payments, and up to $303 million of commercial milestone payments and tiered single-digit royalties on net sales of CTX-009 in oncology. ABL Bio is also eligible to receive up to $75 million in development and regulatory milestones and up to $110 million in commercial milestone payments and tiered, single-digit royalties on net sales of CTX-009 in ophthalmology.

In May 2021, the Company and ABL Bio terminated license agreements to several preclinical assets. As a result of the return of these assets to ABL Bio and termination of the license agreements, the Company is eligible to receive royalty payments if ABL Bio develops or licenses two bispecific antibodies that were previously licensed to the Company.

Adimab Agreement

The Company entered into a collaboration agreement with Adimab, LLC on October 16, 2014. The agreement includes provisions for payment of royalties at rates ranging in the single digits as a percentage of future net sales within a specified term from the first commercial sale for certain antibodies, including our product candidate, CTX-471. There were no milestone payments made during 2023. As of September 30, 2023, future potential milestone payments in connection with this agreement amounted to $2.0 million.

Note 1 - Nature of Business and Basis of Presentation (Details Textual) $ in Millions	54 Months Ended
	Sep. 30, 2022 USD ($)
Proceeds from Issuance or Sale of Equity	$ 412
Cash and Marketable Securities	$ 164

Note 12 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Proceeds from Issuance of Common Stock	$ 3,126	$ 0
At The Market [Member]
Stock Issued During Period, Shares, New Issues	951,873
Shares Issued, Price Per Share	$ 3.28
Proceeds from Issuance of Common Stock	$ 3,100
Proceeds from Issuance of Common Stock, Net	$ 3,000

Note 3 - Fair Value Measurements - Financial Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Marketable Securities	$ 133,277	$ 151,663
Corporate Debt Securities [Member]
Marketable Securities	41,633	87,760
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Marketable Securities	48,889	37,682
Certificates of Deposit [Member]
Marketable Securities	19,547	19,667
Asset-Backed Securities [Member]
Marketable Securities	8,426	6,554
US Treasury Securities [Member]
Marketable Securities	14,782
Fair Value, Recurring [Member]
Total assets	133,277	161,101
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Marketable Securities	41,633	87,760
Fair Value, Recurring [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Marketable Securities	48,889	37,682
Fair Value, Recurring [Member] \| Certificates of Deposit [Member]
Marketable Securities	19,547	19,667
Fair Value, Recurring [Member] \| Asset-Backed Securities [Member]
Marketable Securities	8,426	6,554
Fair Value, Recurring [Member] \| Cash and Cash Equivalents [Member]
Marketable Securities		9,438
Fair Value, Recurring [Member] \| US Treasury Securities [Member]
Marketable Securities	14,782
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total assets	63,671	47,120
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Corporate Debt Securities [Member]
Marketable Securities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Marketable Securities	48,889	37,682
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Certificates of Deposit [Member]
Marketable Securities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Asset-Backed Securities [Member]
Marketable Securities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Cash and Cash Equivalents [Member]
Marketable Securities		9,438
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| US Treasury Securities [Member]
Marketable Securities	14,782
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total assets	69,606	113,981
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities [Member]
Marketable Securities	41,633	87,760
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Marketable Securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Certificates of Deposit [Member]
Marketable Securities	19,547	19,667
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Asset-Backed Securities [Member]
Marketable Securities	8,426	6,554
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Cash and Cash Equivalents [Member]
Marketable Securities		0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| US Treasury Securities [Member]
Marketable Securities	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total assets	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Corporate Debt Securities [Member]
Marketable Securities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Marketable Securities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Certificates of Deposit [Member]
Marketable Securities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Asset-Backed Securities [Member]
Marketable Securities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Cash and Cash Equivalents [Member]
Marketable Securities		$ 0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| US Treasury Securities [Member]
Marketable Securities	$ 0

Note 7 - Commitments and Contingencies - Undiscounted Cash Flows Reconciled to Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Remainder of 2023	$ 224
2024	1,379
2025	543
Total minimum lease payments	2,146
Less: amount of lease payments representing interest	(103)
Present value of future minimum lease payments	2,043
Less: operating lease obligations, current portion	(1,174)	$ (1,097)
Operating lease obligations, long-term portion	$ 869	$ 1,838

Note 11 - License, Research and Collaboration Agreements (Details Textual) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Nov. 30, 2018	Sep. 30, 2023
ABL Bio Agreement [Member]
Upfront Payment	$ 5,000
Development Milestone Payment	6,000
Maximum Development and Regulatory Milestone Payments	96,000
ABL Bio Agreement [Member] \| Oncology [Member]
Maximum Commercial Milestone Payments and Royalties	303,000
ABL Bio Agreement [Member] \| Ophthalmology [Member]
Maximum Development and Regulatory Milestone Payments	75,000
Maximum Commercial Milestone Payments and Royalties	$ 110,000
Adimab Agreement [Member]
Milestone Payments Paid		$ 0
Milestone Payment Obligation		$ 2,000

Note 7 - Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2023

Notes Tables

Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]

Remainder of 2023	$	224
Years ending December 31,
2024		1,379
2025		543
Total minimum lease payments		2,146
Less: amount of lease payments representing interest		(103	)
Present value of future minimum lease payments		2,043
Less: operating lease obligations, current portion		(1,174	)
Operating lease obligations, long-term portion	$	869

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operating Expense [Member]
Research and development	$ 8,831	$ 9,791	$ 25,694	$ 20,069
General and administrative	3,095	2,807	9,276	8,698
Total operating expenses	11,926	12,598	34,970	28,767
Loss from operations	(11,926)	(12,598)	(34,970)	(28,767)
Other income	1,962	623	5,891	1,136
Loss before income tax expense	(9,964)	(11,975)	(29,079)	(27,631)
Income tax expense	0	0	0	0
Net loss	$ (9,964)	$ (11,975)	$ (29,079)	$ (27,631)
Net loss per share - basic and diluted (in dollars per share)	$ (0.08)	$ (0.12)	$ (0.23)	$ (0.27)
Basic and diluted weighted average shares outstanding (in shares)	127,424	101,010	126,837	100,939
Other comprehensive loss:
Net loss	$ (9,964)	$ (11,975)	$ (29,079)	$ (27,631)
Unrealized gain (loss) on marketable securities	77	(129)	(128)	(641)
Comprehensive loss	$ (9,887)	$ (12,104)	$ (29,207)	$ (28,272)

Note 8 - Stock-based Compensation - Weighted Average Assumptions (Details)	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Expected term (in years) (Year)	6 years	6 years
Risk-free rate	3.80%	2.00%
Expected volatility	88.00%	94.00%

Note 7 - Commitments and Contingencies

9 Months Ended

Sep. 30, 2023

Notes to Financial Statements

Commitments and Contingencies Disclosure [Text Block]

7. Commitments and Contingencies

Leases

The Company has evaluated its leases under ASC 842, Leases, and determined that it has one lease that is classified as an operating lease. The classification of this lease is consistent with the Company’s determination under the previous accounting standard.

When available, the Company will use the rate implicit in the lease to discount lease payments to present value; however, the Company’s current lease does not provide an implicit rate. Therefore, the Company used its incremental borrowing rate to discount the lease payments based on the date of the lease commencement.

The Company has one operating lease for its corporate office and laboratory facility (“Facility”) that was signed in December 2020. The Company moved into the Facility in January 2021. The Facility lease has an initial term of four years and five months, beginning on January 1, 2021. The Facility lease contains scheduled rent increases over the lease term. The discount rate used for the Facility lease is 6.25%, and the remaining lease term of the Facility lease is one year and eight months as of September 30, 2023. Cash payments related to the Facility were $0.3 million for the three months ending September 30, 2023 and 2022 and $1.0 million for the nine months ending September 30, 2023 and 2022.

The table below presents the undiscounted cash flows for the lease term. The undiscounted cash flows are reconciled to the operating lease liabilities recorded on the condensed consolidated balance sheet (in thousands):

Remainder of 2023	$	224
Years ending December 31,
2024		1,379
2025		543
Total minimum lease payments		2,146
Less: amount of lease payments representing interest		(103	)
Present value of future minimum lease payments		2,043
Less: operating lease obligations, current portion		(1,174	)
Operating lease obligations, long-term portion	$	869

Milestone payments

As part of the ABL Bio Agreement, the Company is obligated to pay certain development milestone payments. See Note 11 for additional information on the ABL Bio Agreement.

Note 7 - Commitments and Contingencies (Details Textual) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022	Dec. 31, 2020
Number of Operating Leases						1
Lessee, Operating Lease, Term of Contract (Year)					4 years 5 months 1 day
Lessee, Operating Lease, Discount Rate					6.25%
Lessee, Operating Lease, Remaining Lease Term (Year)	1 year 7 months 28 days		1 year 7 months 28 days
Operating Lease, Payments	$ 0.3	$ 0.3	$ 1.0	$ 1.0