0001171843-24-001516 | 10-K | XBRL Viewer

Other Nonoperating Income and Expense [Text Block]

12.

Other income

Other income consisted of the following:

	December 31,
	2023		2022
	(000's)
Interest income, net	$	7,869	$	2,360
Realized gain on disposal of equipment		—		70
Total other income	$	7,869	$	2,430

Note 2 - Liquidity, Uncertainties and Going Concern (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Retained Earnings (Accumulated Deficit), Total	$ (315,308)	$ (272,814)

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 24,228	$ 34,946
Marketable securities	128,233	151,663
Prepaid expenses and other current assets	1,420	8,182
Total current assets	153,881	194,791
Property and equipment, net	898	1,567
Operating lease, right-of-use ("ROU") asset	1,776	2,967
Other assets	320	320
Total assets	156,875	199,645
Current liabilities:
Accounts payable	4,090	3,382
Accrued expenses	2,514	11,690
Operating lease obligations, current portion	1,197	1,097
Total current liabilities	7,801	16,169
Operating lease obligations, net of current portion	536	1,838
Total liabilities	8,337	18,007
Commitments and Contingencies
Stockholders' equity:
Common stock, $0.0001 par value: 300,000 shares authorized; 127,668 shares issued and outstanding at December 31, 2023; 126,495 shares issued and 126,302 shares outstanding at December 31, 2022	13	13
Additional paid-in-capital	463,796	454,741
Accumulated other comprehensive income (loss)	37	(302)
Accumulated deficit	(315,308)	(272,814)
Total stockholders' equity	148,538	181,638
Total liabilities and stockholders' equity	$ 156,875	$ 199,645

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (42,494)	$ (39,225)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	699	782
Gain on disposal of equipment	0	(70)
Share-based compensation	6,120	5,330
Amortization of premium and discount on marketable securities	(3,226)	(801)
ROU asset amortization	1,191	1,122
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	6,762	(5,591)
Accounts payable	708	2,515
Accrued expenses	(9,176)	2,915
Operating lease liability	(1,202)	(1,102)
Net cash used in operating activities	(40,618)	(34,125)
Cash flows from investing activities:
Purchases of marketable securities	(155,418)	(200,119)
Proceeds from sale or maturities of marketable securities	182,413	48,955
Purchases of property and equipment	(30)	(212)
Proceeds from sale of equipment	0	176
Net cash provided by (used) in investing activities	26,965	(151,200)
Cash flows from financing activities:
Proceeds from issuance of common stock	3,126	76,237
Issuance costs from issuance of common stock	(94)	(495)
Proceeds from exercise of stock options	62	15
Taxes related to the vesting of RSUs	159	(0)
Net cash provided by financing activities	2,935	75,757
Net change in cash and cash equivalents	(10,718)	(109,568)
Cash and cash equivalents at beginning of year	34,946	144,514
Cash and cash equivalents at end of year	24,228	34,946
Supplemental disclosure of cash flow information
Unrealized (gain) loss on marketable securities	$ (339)	$ 302

Note 9 - Stock-based Compensation - Weighted Average Assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Expected term (in years) (Year)	6 years	6 years
Risk-free rate	3.83%	2.02%
Expected volatility	87.00%	94.00%

Note 15 - Income Taxe3

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Text Block]

13.

Income Taxes

The Company had no income tax for the years ended December 31, 2023 and 2022.

The effective tax rate of our provision for income taxes differs from the federal statutory rate for the periods presented as follows:

	December 31,
	2023			2022
Statutory rate		21.0	%		21.0	%
State taxes		7.9	%		5.6	%
Share-based compensation & other nondeductible expenses		1.5	%		-2.7	%
Research credits		7.3	%		1.4	%
Other		-0.6	%		-0.1	%
Change in valuation allowance		-37.1	%		-25.2	%
Total		0.0	%		0.0	%

The Company accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are determined based on differences between the financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. In determining the need for a valuation allowance, management reviews both positive and negative evidence, including current and historical results of operations, future income projections and the overall prospects of our business. Based upon management’s assessment of all available evidence, the Company believes that it is more-likely-than-not that the deferred tax assets will not be realizable, and therefore, a valuation allowance has been established. The valuation allowance for deferred tax assets was approximately $43.8 million and $28.0 million as of December 31, 2023 and 2022, respectively.

As of December 31, 2023, the Company has U.S. federal and state net operating loss carryforwards (“NOLs”) of $65.5 million and $58.8 million, respectively. As of December 31, 2023, the Company has federal and state research and development credit carryforwards (“R&D credits”) of $3.7 million and $3.4 million, respectively. For income tax purposes, federal NOLs will not expire since they were generated after 2017 and federal R&D credits will begin expiring in 2039. For income tax purposes, state NOLs and state R&D credits will begin to expire in 2040 and 2031, respectively.

Net operating loss and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service (the “IRS”) and may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50% as defined under Sections 382 and 383 in the Internal Revenue Code, which could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the Company’s value immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has not yet conducted a study to determine if any such limitation exists.

The Tax Cuts and Jobs Act of 2017 (“TCJA”) amended IRC Section 174 to require capitalization of all research and developmental (R&D) costs incurred in tax years beginning after December 31, 2021. These costs are required to be amortized with a half-year convention over five years if the R&D activities are performed in the U.S., or over 15 years if the activities were performed outside the U.S. The Company capitalized approximately $36.9 million and amortized $6.9 million of R&D expenses incurred for the year ended December 31, 2023.

As of December 31, 2023 and 2022, the Company had no uncertain tax positions, and as such, no related interest or penalties have been recorded in the statements of operations and comprehensive loss. The Company recognizes interest and penalties related to uncertain tax positions as a component of income tax expense. All tax years of the Company from inception are open to examination by federal tax and state tax authorities. To the extent utilized in future years’ tax returns, net operating loss carryforwards at December 31, 2023 will remain subject to examination until the respective tax year is closed. The Company has not been informed by any tax authorities for any jurisdiction that any of its tax years is under examination as of December 31, 2023.

Significant components of the Company’s deferred tax assets and liabilities are as follows:

	December 31,
	2023			2022
Deferred tax assets	(000's)
Federal net operating loss carryforwards	$	13,760		$	12,405
State net operating loss carryforwards		3,719			2,687
Research and development credits		6,387			3,273
Section 174 Capitalization		15,525			7,294
Share-based compensation		2,701			701
Lease liabilities		474			801
Capitalized licensing fees		1,484			1,591
Other		234			70
Subtotal		44,284			28,822
Less valuation allowance		(43,799	)		(28,013	)
Deferred tax assets, net of valuation allowance		485			809

Deferred tax liabilities
Right-of-use assets		(485	)		(809	)
Other		—			—
Net deferred tax assets	$	—		$	—

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

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+ Details

Note 3 - Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Significant Accounting Policies [Text Block]

3.	Summary of Significant Accounting Policies

Basis of Presentation

The accompanying consolidated financial statements are presented in U.S. dollars and have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and as amended by Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Compass Therapeutics, Inc., and its wholly-owned subsidiaries, including Compass Therapeutics LLC, Compass Therapeutics Advisors Inc., Trigr Therapeutics, Inc. and Compass Therapeutics Securities Corporation. All intercompany accounts and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of financial statements in conformity with 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 financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, the accrual of research and development expenses, useful lives of equipment, interest rate and term operating lease ROU and liability, the percentage of completion of contractual arrangements, future cash expenditures for liquidity estimates, the valuation of common stock and estimates associated with stock-based awards. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results could differ from those estimates. Changes in estimates are recorded prospectively in the period that they become known.

Segment Information

Operating segments are defined as components of an enterprise for which separate and discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company has one operating segment. The Company’s chief operating decision-maker, its chief executive officer, manages the Company’s operations on a consolidated basis for the purpose of allocating resources. All the Company’s long-lived assets are held in the United States.

Cash and Cash Equivalents

The Company considers all highly liquid investments that are readily convertible into cash with original maturities of three months or less from the date of purchase to be cash equivalents. Cash and cash equivalents include cash held in banks and amounts held in money market funds or commercial paper. Cash equivalents are stated at cost, which approximates market value. Cash and Cash equivalents were $24.2 million and $34.9 million on December 31, 2023 and 2022, respectively.

Marketable Securities

All of the Company’s investment securities are debt securities and bank instruments. The Company carries these investments at fair value. Unrealized gains and losses, if any, are reported as a separate component of stockholders’ equity. The cost of investment securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion are included in interest income. Realized gains and losses, if any, are also included in interest income. The cost of securities sold is based on the specific identification method.

Concentrations of Credit Risk

Financial instruments, which potentially subject the Company to concentrations of credit risk, principally consist of cash equivalents and marketable securities. The Company invests its excess cash primarily in money market funds, U.S. treasury notes, and high quality, marketable debt instruments of corporations in accordance with the Company’s investment policy. The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. The Company has not experienced any realized losses related to its cash equivalents and marketable securities.

Property and Equipment

Property and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation and amortization are recorded using the straight-line method over the estimated useful lives of the related assets as follows:

Asset Classification	Estimated Useful Life
Equipment	5 years
Furniture and fixtures	7 years
Software	5 years
Leasehold improvements	Lesser of estimated useful life or lease term

Estimated useful lives are periodically assessed to determine if changes are appropriate. Maintenance and repairs are charged to expense as incurred. When assets are retired or otherwise disposed of, the cost of these assets and related accumulated depreciation or amortization are eliminated from the consolidated balance sheet and any resulting gains or losses are included in the consolidated statement of operations and comprehensive loss in the period of disposal. Costs for capital assets not yet placed into service are capitalized as construction-in-progress and depreciated once placed into service.

Impairment of Long-Lived Assets

Long-lived assets consist of property, equipment and right-of-use (“ROU”) assets. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized in the consolidated statements of operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. The Company did not record any impairment losses on long-lived assets during the years ended December 31, 2023 and 2022.

Fair Value Measurements

Certain assets and liabilities of the Company are carried at fair value under GAAP. Fair value is defined 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. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

●

Level 1 – Quoted prices in active markets for identical assets or liabilities.

●

Level 2 – Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets and liabilities, or other inputs that are observable or can be corroborated by observable market data.

●

Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.

An entity may choose to measure many financial instruments and certain other items at fair value at specified election dates. Subsequent unrealized gains and losses on items for which the fair value option has been elected are reported in earnings.

Research and Development Costs

Costs associated with internal research and development and external research and development services, including drug development and preclinical studies, are expensed as incurred. Research and development expenses include costs for salaries, employee benefits, subcontractors, facility-related expenses, depreciation and amortization, stock-based compensation, third-party license fees, laboratory supplies, and external costs of outside vendors engaged to conduct discovery, preclinical and clinical development activities and clinical trials as well as to manufacture clinical trial materials and other costs. The Company recognizes external research and development costs based on an evaluation of the progress to completion of specific tasks using information provided to the Company by its service providers.

Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. Such prepaid expenses are recognized as an expense when the goods have been delivered or the related services have been performed, or when it is no longer expected that the goods will be delivered, or the services rendered.

Costs associated with licenses of technology acquired as part of collaborative arrangements are expensed as incurred and are generally included in research and development expense in the consolidated statements of operations if it is determined the license has no alternative future use.

Accrued Research and Development Expenses

The Company has entered into various research and development and other agreements with commercial firms, researchers, universities and others for provisions of goods and services. These agreements are generally cancelable, and the related costs are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research and development costs. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the studies or clinical trials, including the phase or completion of events, invoices received and contracted costs. Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ materially from the Company’s estimates. The Company’s historical accrual estimates have not been materially different from the actual costs.

Patent Costs

All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expense in the consolidated statements of operations.

Stock-Based Compensation

The Company recognizes the grant‑date fair value of stock‑based awards issued to employees and nonemployee board members as compensation expense on a straight‑line basis over the service period of the award. The Company uses the Black‑Scholes option pricing model to determine the grant‑date fair value of stock options and adjusts expense for forfeitures in the periods they occur.

The fair value of each equity award was determined by the Company on the date of grant and by using the methods and assumptions discussed below. Certain of these inputs are subjective and generally require judgment to determine.

Stock price: The stock price used to value equity awards is based on the closing price of the Company’s common stock as reported on the date of the grant. For equity awards issued after June 2020 until the Company started trading on a public market in the second quarter of 2021, the valuation of the Company’s common stock was $5.00 per share, which was the share price paid by outside investors in the Company’s Private Placement in June 2020.

Expected term: The expected term of the equity award represents the weighted average period the award is expected to be outstanding. The Company uses the simplified method for estimating the expected term as provided by the Securities and Exchange Commission. The simplified method calculates the expected term as the average time to vesting and the contractual life of the award.

Expected volatility – The expected volatility is calculated based on the historical volatility of our common stock over the expected term of the option.

Risk-free interest rate – The risk-free rate assumption is based on U.S. Treasury instruments, the terms of which were consistent with the expected term of the Company’s equity award.

Expected dividend – The Company has not paid and does not intend to pay dividends.

Net Loss per Share

Basic loss per share is computed by dividing net loss by the weighted average number of shares of common stock outstanding during each period. Diluted loss per share includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred stock, stock options, restricted stock units, unvested restricted stock awards and common stock warrants that would result in the issuance of incremental shares of common stock. In computing the basic and diluted net loss per share, the weighted average number of shares remains the same for both calculations due to the fact that when a net loss exists, dilutive shares are not included in the calculation as the impact is anti-dilutive.

The following potentially dilutive securities outstanding as of December 31, 2023 and 2022 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive:

	December 31,
	2023		2022
	(000's)
Restricted stock units		1,500		900
Stock options		7,876		5,378
Nonvested restricted stock		—		193
Total		9,376		6,471

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, operating losses and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment date. Deferred tax assets are reduced, as necessary, by a valuation allowance when management determines it is more likely than not that some or all of the deferred tax benefits will not be realized.

The Company files income tax returns in the U.S. Federal jurisdiction and in various states. The Company has tax net operating loss carryforwards that are subject to examination for a number of years beyond the year in which they were generated for tax purposes. Since a portion of these net operating loss carryforwards may be utilized in the future, many of these net operating loss carryforwards will remain subject to examination.

New Accounting Pronouncements

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to tax disclosures. The purpose of ASU 2023-09 is to enhance the transparency and decision usefulness of income tax disclosures. The ASU requires a significant expansion of the granularity of the income tax rate reconciliation as well as an expansion of other income tax disclosures. The ASU is effective on a prospective basis for annual periods beginning after December 15, 2024. This will result in additional disclosures being included in our consolidated financial statements, once adopted. The Company is evaluating the impact of ASU 2023-09 and does not expect ASU-2023-09 to have a significant impact on the consolidated financial statements.

Recently Adopted Accounting Pronouncements

In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("ASU 2019-12"), which is intended to simplify the accounting for income taxes. ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing guidance to improve consistent application. The new standard was effective beginning January 1, 2022. The adoption of ASU 2019-12 did not have a material impact on the Company’s financial position and results of operations upon adoption.

The Company adopted Accounting Standards Update ASU No. 2016-13, Financial Instruments — Credit Losses (Topic 326): Measurement of Credit Losses of Financial Instruments on January 1, 2023. Marketable debt securities for which the estimated fair value is below amortized cost are evaluated for credit impairment. Credit impairment is recorded through the statements of operations via an allowance for credit losses and any remaining unrealized gains and losses are reported as a component of other comprehensive income (loss) within the statements of operations and comprehensive loss and as a separate component of stockholders’ equity. For all marketable securities which the estimated fair value was below amortized cost as of December 31, 2023 and 2022, the decline in fair value was not driven by credit impairment.

There are no other pending accounting pronouncements that are expected to have a material impact on the Company’s consolidated financial statements.

Note 11 - Commitments and Contingencies (Details Textual) $ in Millions	6 Months Ended	12 Months Ended		42 Months Ended
	Dec. 31, 2023	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2023
Number of Operating Leases	1	1
Lessee, Operating Lease, Term of Contract	4 years 4 months 30 days	4 years 4 months 30 days
Lessee, Operating Lease, Discount Rate	6.25%	6.25%
Lessee, Operating Lease, Remaining Lease Term	2 years 4 months 30 days	2 years 4 months 30 days
Operating Lease, Payments		$ 1.3	$ 1.3
Defined Contribution Plan, Cost		$ 0.2	$ 0.1
Maximum [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%			4.00%

Note 13 - Income Taxes - Schedule of Effective Tax Rate of Provision for Income Taxes differs from Federal Statutory Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Statutory rate	21.00%	21.00%
State taxes	7.90%	5.60%
Share-based compensation & other nondeductible expenses	1.50%	(2.70%)
Research credits	7.30%	1.40%
Other	(0.60%)	(0.10%)
Change in valuation allowance	(37.10%)	(25.20%)
Total	0.00%	0.00%

Note 4 - Fair Value Measurements - Financial Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Marketable Securities	$ 128,233	$ 151,663
Corporate Debt Securities [Member]
Marketable Securities	54,281	87,760
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Marketable Securities	28,534	37,682
Certificates of Deposit [Member]
Marketable Securities	18,866	19,667
Asset-Backed Securities [Member]
Marketable Securities	10,472	6,554
US Treasury Securities [Member]
Marketable Securities	16,080
Fair Value, Recurring [Member]
Total assets	128,808	161,101
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Marketable Securities	54,281	87,760
Fair Value, Recurring [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Marketable Securities	28,534	37,682
Fair Value, Recurring [Member] \| Certificates of Deposit [Member]
Marketable Securities	18,866	19,667
Fair Value, Recurring [Member] \| Asset-Backed Securities [Member]
Marketable Securities	10,472	6,554
Fair Value, Recurring [Member] \| Cash and Cash Equivalents [Member]
Marketable Securities	575	9,438
Fair Value, Recurring [Member] \| US Treasury Securities [Member]
Marketable Securities	16,080
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total assets	45,189	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	28,534	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	575	9,438
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| US Treasury Securities [Member]
Marketable Securities	16,080
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total assets	83,619	113,981
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities [Member]
Marketable Securities	54,281	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	18,866	19,667
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Asset-Backed Securities [Member]
Marketable Securities	10,472	6,554
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Cash and Cash Equivalents [Member]
Marketable Securities	0	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	$ 0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| US Treasury Securities [Member]
Marketable Securities	$ 0

Note 7 - Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2023

Schedule of Accrued Liabilities [Table Text Block]

	December 31,
	2023		2022
	(000's)
Project expenses	$	336	$	10,038
Compensation and benefits		1,938		1,556
Other		240		96
Total accrued expenses	$	2,514	$	11,690

Note 8 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	Jun. 30, 2023	Nov. 30, 2022	Dec. 31, 2023	Dec. 31, 2022
Proceeds from Issuance of Common Stock			$ 3,126	$ 76,237
Payments of Stock Issuance Costs			$ 94	$ 495
Private Investment in Public Entity Offering [Member]
Stock Issued During Period, Shares, New Issues		25,000,000
Shares Issued, Price Per Share		$ 3.21
Proceeds from Issuance of Common Stock		$ 80,300
Payments of Stock Issuance Costs		4,500
Proceeds from Issuance of Common Stock, Net		$ 75,700
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 4 - Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2023

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

	Fair Value Measurements as of December 31, 2023 (000's):
	Quoted Prices		Significant
	in Active		Other		Significant
	Markets for		Observable		Unobservable
	Identical Assets		Inputs		Inputs
	(Level 1)		(Level 2)		(Level 3)		Fair Value
Assets
Corporate bonds	$	—	$	54,281	$	—	$	54,281
Commercial paper		28,534		—		—		28,534
Certificates of deposit		—		18,866		—		18,866
U.S. government treasuries		16,080		—		—		16,080
Asset-backed securities		—		10,472		—		10,472
Money market funds (cash equivalents)		575		—		—		575
Total assets	$	45,189	$	83,619	$	—	$	128,808

	Fair Value Measurements as of December 31, 2022 (000's):
	Quoted Prices		Significant
	in Active		Other		Significant
	Markets for		Observable		Unobservable
	Identical Assets		Inputs		Inputs
	(Level 1)		(Level 2)		(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
Money market funds (cash equivalents)		9,438		—		—		9,438
Total assets	$	47,120	$	113,981	$	—	$	161,101

Note 4 - Fair Value Measurements

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Text Block]

4.	Fair Value Measurements

The following tables present information about the Company’s financial assets and liabilities 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:

	Fair Value Measurements as of December 31, 2023 (000's):
	Quoted Prices		Significant
	in Active		Other		Significant
	Markets for		Observable		Unobservable
	Identical Assets		Inputs		Inputs
	(Level 1)		(Level 2)		(Level 3)		Fair Value
Assets
Corporate bonds	$	—	$	54,281	$	—	$	54,281
Commercial paper		28,534		—		—		28,534
Certificates of deposit		—		18,866		—		18,866
U.S. government treasuries		16,080		—		—		16,080
Asset-backed securities		—		10,472		—		10,472
Money market funds (cash equivalents)		575		—		—		575
Total assets	$	45,189	$	83,619	$	—	$	128,808

	Fair Value Measurements as of December 31, 2022 (000's):
	Quoted Prices		Significant
	in Active		Other		Significant
	Markets for		Observable		Unobservable
	Identical Assets		Inputs		Inputs
	(Level 1)		(Level 2)		(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
Money market funds (cash equivalents)		9,438		—		—		9,438
Total assets	$	47,120	$	113,981	$	—	$	161,101

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 6 - Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Total property and equipment–at cost	$ 7,165	$ 7,135
Less: Accumulated depreciation and amortization	(6,267)	(5,568)
Property and equipment, net	898	1,567
Equipment [Member]
Total property and equipment–at cost	5,167	5,137
Furniture and Fixtures [Member]
Total property and equipment–at cost	22	22
Leasehold Improvements [Member]
Total property and equipment–at cost	1,612	1,612
Software Development [Member]
Total property and equipment–at cost	$ 364	$ 364

Note 15 - Income Taxe3 (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Expense (Benefit)	$ 0	$ 0
Deferred Tax Assets, Valuation Allowance	43,799	28,013
Deferred Tax Assets, Capitalized Research and Development Expenses	36,900
Deferred Tax Assets, Amortized Research and Development Expenses	6,900
Unrecognized Tax Benefits	0	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total	0	$ 0
Domestic Tax Authority [Member]
Operating Loss Carryforwards	65,500
Domestic Tax Authority [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	3,700
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	58,800
State and Local Jurisdiction [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	$ 3,400

Note 9 - Stock-based Compensation - Summary of Restricted Stock Activity (Details) - Restricted Stock [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Unvested, shares (in shares)	193	471
Unvested, estimated fair value per share (in dollars per share)	$ 1.74	$ 1.76
Granted, shares (in shares)	0	0
Granted, estimated fair value per share (in dollars per share)	$ 0	$ 0
Vested, shares (in shares)	(193)	(258)
Vested, estimated fair value per share (in dollars per share)	$ 1.74	$ 1.77
Forfeited or canceled, shares (in shares)	0	(20)
Forfeited or canceled, estimated fair value per share (in dollars per share)	$ 0	$ 1.77
Unvested, shares (in shares)	0	193
Unvested, estimated fair value per share (in dollars per share)	$ 0	$ 1.74

Note 12 - Other Income - Schedule of Other Income (Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Interest income, net	$ 7,869	$ 2,360
Realized gain on disposal of equipment	0	70
Total other income	$ 7,869	$ 2,430

Note 3 - Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment, Estimated Useful Lives [Table Text Block]

Asset Classification	Estimated Useful Life
Equipment	5 years
Furniture and fixtures	7 years
Software	5 years
Leasehold improvements	Lesser of estimated useful life or lease term

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	December 31,
	2023		2022
	(000's)
Restricted stock units		1,500		900
Stock options		7,876		5,378
Nonvested restricted stock		—		193
Total		9,376		6,471

Note 1 - Formation and Business of the Company

12 Months Ended

Dec. 31, 2023

Business Description and Basis of Presentation [Text Block]

1.	Formation and Business of the Company

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 drug 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 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.

Note 9 - Stock-based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stock-based compensation expense	$ 6,120	$ 5,330
Research and Development Expense [Member]
Stock-based compensation expense	1,998	1,793
General and Administrative Expense [Member]
Stock-based compensation expense	$ 4,122	$ 3,537

Note 13 - Income Taxes - Significant Components of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Federal net operating loss carryforwards	$ 13,760	$ 12,405
State net operating loss carryforwards	3,719	2,687
Research and development credits	6,387	3,273
Section 174 Capitalization	15,525	7,294
Share-based compensation	2,701	701
Lease liabilities	474	801
Capitalized licensing fees	1,484	1,591
Other	234	70
Subtotal	44,284	28,822
Less valuation allowance	(43,799)	(28,013)
Deferred tax assets, net of valuation allowance	485	809
Right-of-use assets	(485)	(809)
Other	0	0
Net deferred tax assets	$ 0	$ 0

Note 5 - Marketable Securities

12 Months Ended

Dec. 31, 2023

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

5.	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 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 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 consolidated balance sheet.

The following tables summarize marketable securities held at December 31, 2023 and 2022 (in thousands):

	Fair Value Measurements as of December 31, 2023 Using:
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	54,256	$	74	$	(49	)	$	54,281
Commercial paper		28,507		30		(3	)		28,534
Certificates of deposit		18,850		17		(1	)		18,866
U.S. government treasuries		16,127		3		(50	)		16,080
Asset-backed securities		10,456		23		(7	)		10,472
Total assets	$	128,196	$	147	$	(110	)	$	128,233

	Fair Value Measurements as of December 31, 2022 Using:
	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 December 31,
	2023		2022
Maturing in one year or less		93,117		134,620
Maturing after one year through two years		35,116		17,043
Total	$	128,233	$	151,663

Note 3 - Summary of Significant Accounting Policies - Schedule of Estimated Lives (Details)	Dec. 31, 2023
Equipment [Member]
Property, plant and equipment, useful life (Year)	5 years
Furniture and Fixtures [Member]
Property, plant and equipment, useful life (Year)	7 years
Software and Software Development Costs [Member]
Property, plant and equipment, useful life (Year)	5 years

Note 15 - Income Taxe3 (Tables)

12 Months Ended

Dec. 31, 2023

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	December 31,
	2023			2022
Statutory rate		21.0	%		21.0	%
State taxes		7.9	%		5.6	%
Share-based compensation & other nondeductible expenses		1.5	%		-2.7	%
Research credits		7.3	%		1.4	%
Other		-0.6	%		-0.1	%
Change in valuation allowance		-37.1	%		-25.2	%
Total		0.0	%		0.0	%

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	December 31,
	2023			2022
Deferred tax assets	(000's)
Federal net operating loss carryforwards	$	13,760		$	12,405
State net operating loss carryforwards		3,719			2,687
Research and development credits		6,387			3,273
Section 174 Capitalization		15,525			7,294
Share-based compensation		2,701			701
Lease liabilities		474			801
Capitalized licensing fees		1,484			1,591
Other		234			70
Subtotal		44,284			28,822
Less valuation allowance		(43,799	)		(28,013	)
Deferred tax assets, net of valuation allowance		485			809

Deferred tax liabilities
Right-of-use assets		(485	)		(809	)
Other		—			—
Net deferred tax assets	$	—		$	—

Note 9 - Stock-based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Outstanding, options (in shares)	5,378	3,659
Outstanding, weighted average exercise price (in dollars per share)	$ 3.89	$ 5.01
Outstanding, weighted average remaining contractual life (Year)	8 years 18 days	8 years 2 months 26 days	8 years 11 months 23 days
Granted, options (in shares)	2,803	2,277
Granted, weighted average exercise price (in dollars per share)	$ 3.69	$ 2.3
Granted, weighted average remaining contractual life (Year)	9 years 2 months 4 days	8 years 9 months 21 days
Exercised, options (in shares)	(29)	(6)
Exercised, weighted average exercise price (in dollars per share)	$ 1.75	$ 2.26
Exercised, aggregate intrinsic value	$ 35	$ 6
Forfeited/cancelled, options (in shares)	(276)	(552)
Forfeited/cancelled, weighted average exercise price (in dollars per share)	$ 4.29	$ 4.78
Forfeited/cancelled, aggregate intrinsic value	$ 164	$ 118
Outstanding, options (in shares)	7,876	5,378	3,659
Outstanding, weighted average exercise price (in dollars per share)	$ 3.81	$ 3.89	$ 5.01
Outstanding, aggregate intrinsic value	$ 11	$ 6,300
Vested, options (in shares)	3,938
Vested, weighted average exercise price (in dollars per share)	$ 4.22
Vested, weighted average remaining contractual life (Year)	7 years 5 months 4 days
Vested, aggregate intrinsic value	$ 5

Note 3 - Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2021 $ / shares
Number of Operating Segments	1
Cash and cash equivalents	$ 24,228	$ 34,946
Impairment, Long-Lived Asset, Held-for-Use	$ 0	$ 0
Common Stock [Member]
Shares Issued, Price Per Share \| $ / shares			$ 5

Note 11 - Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Text Block]

11.

Commitments and Contingencies

Leases

The Company accounts for operating leases on a straight-line basis over the lease term, with recognition of a right-of-use asset and a corresponding lease liability, initially measured at the present value of the lease payments. For leases with a term of 12 months or less, we recognize lease expense on a straight-line basis over the lease term.

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 five months as of December 31, 2023. As this lease does not provide an implicit rate, the Company used its incremental borrowing rate to discount the lease payments based on the date of the lease commencement. Cash paid for this lease was $1.3 million for the years ended December 31, 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 consolidated balance sheets:

	(000's)
Years ending December 31,
2024	$	1,264
2025		543
Total minimum lease payments		1,807
Less: amount of lease payments representing interest		(74	)
Present value of future minimum lease payments		1,733
Less: operating lease obligations, current portion		(1,197	)
Operating lease obligations, long-term portion	$	536

Defined Contribution Plan

The Company has a 401(k) defined contribution plan (the “401(k) Plan”) for substantially all its employees. Eligible employees may make pre-tax or post-tax (Roth) contributions to the 401(k) Plan up to statutory limits. Since January 1, 2020, the Company has been matching employee contributions to the plan up to 4% of salary. On July 1, 2023, the Company increased the employee matching contribution from 4% to 6%. The Company made matching contributions of $0.2 million and $0.1 million for the years ended December 31, 2023 and 2022, respectively.

Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ 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	$ 373,657	$ 0	$ (233,589)	$ 140,078
Common shares issued in PIPE Offering, net (in shares)	25,000
Common shares issued in PIPE Offering, net	$ 3	75,739	0	0	$ 75,742
Common stock issued upon exercise of options (in shares)	6				6
Common stock issued upon exercise of options	$ 0	15	0	0	$ 15
Share-based awards (in shares)	559
Share-based awards	$ 0	0	0	0	0
Stock-based compensation	$ 0	5,330	0	0	5,330
Cancelled shares (in shares)	(95)
Unrealized gain (loss) on marketable securities	$ 0	0	(302)	0	(302)
Net loss	$ 0	0	0	(39,225)	(39,225)
Balance (in shares) at Dec. 31, 2022	126,302
Balance at Dec. 31, 2022	$ 13	454,741	(302)	(272,814)	181,638
Common shares issued in PIPE Offering, net (in shares)	952
Common shares issued in PIPE Offering, net	$ 0	3,032	0	0	$ 3,032
Common stock issued upon exercise of options (in shares)	29				29
Common stock issued upon exercise of options	$ 0	62	0	0	$ 62
Share-based awards (in shares)	385
Share-based awards	$ 0	(159)	0	0	(159)
Stock-based compensation	0	6,120	0	0	6,120
Unrealized gain (loss) on marketable securities	0	0	339	0	339
Net loss	$ 0	0	0	(42,494)	(42,494)
Balance (in shares) at Dec. 31, 2023	127,668
Balance at Dec. 31, 2023	$ 13	$ 463,796	$ 37	$ (315,308)	$ 148,538

Note 7 - Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Project expenses	$ 336	$ 10,038
Compensation and benefits	1,938	1,556
Other	240	96
Total accrued expenses	$ 2,514	$ 11,690

Note 12 - Other Income (Tables)

12 Months Ended

Dec. 31, 2023

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

	December 31,
	2023		2022
	(000's)
Interest income, net	$	7,869	$	2,360
Realized gain on disposal of equipment		—		70
Total other income	$	7,869	$	2,430

Note 9 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

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

	Year Ended December 31,
	2023		2022
	(000's)
Research and development	$	1,998	$	1,793
General and administrative		4,122		3,537
Total	$	6,120	$	5,330

Nonvested Restricted Stock Shares Activity [Table Text Block]

	Shares (000's)			Estimated Fair Value Per Share
Unvested, December 31, 2021		471		$	1.76
Granted		—		$	—
Vested		(258	)	$	1.77
Forfeited or canceled		(20	)	$	1.77
Unvested, December 31, 2022		193		$	1.74
Granted		—		$	—
Vested		(193	)	$	1.74
Forfeited or canceled		—		$	—
Unvested, December 31, 2023		—		$	—

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

	Number of Nonvested Options (000's)			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value (000's)
Outstanding at December 31, 2021		3,659		$	5.01		8.98	$	—
Granted		2,277		$	2.30		8.81	$	—
Exercised		(6	)	$	2.26		—	$	6
Forfeited/cancelled		(552	)	$	4.78		—	$	118
Outstanding at December 31, 2022		5,378		$	3.89		8.24	$	6,316
Granted		2,803		$	3.69		9.18	$	—
Exercised		(29	)	$	1.75		—	$	35
Forfeited/cancelled		(276	)	$	4.29		—	$	164
Outstanding at December 31, 2023		7,876		$	3.81		8.05	$	11
Vested at December 31, 2023		3,938		$	4.22		7.43	$	5

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

	Year Ended December 31,
	2023			2022
Expected term (in years)		6.0			6.0
Risk-free rate		3.83	%		2.02	%
Expected volatility		87	%		94	%

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, 2021		1,200		$	3.83	$	4,596
Granted		—			—		—
Vested		(300	)		3.83		(1,149	)
Forfeited or canceled		—			—		—
Unvested, December 31, 2022		900		$	3.83	$	3,447
Granted		900		$	3.93	$	3,537
Vested		(300	)		3.83		(1,149	)
Forfeited or canceled		—			—		—
Unvested, December 31, 2023		1,500		$	3.83	$	5,745

Note 2 - Liquidity, Uncertainties and Going Concern

12 Months Ended

Dec. 31, 2023

Substantial Doubt about Going Concern [Text Block]

2.	Liquidity, Uncertainties and Going Concern

The Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that the consolidated financial statements are issued.

Since its inception, the Company has funded its operations primarily with proceeds from the sale of its equity securities. The Company has incurred recurring losses since its inception and had an accumulated deficit of $315.3 million on December 31, 2023. The Company expects to continue o generate operating losses for the foreseeable future. The Company expects that its cash, cash equivalents and marketable securities will be sufficient to fund its operating expenses and capital expenditure requirements into mid-2026. The future viability of the Company beyond that point is dependent on its ability to raise additional capital to finance its operations.

The Company is subject to risks common to early stage companies in the biotechnology industry including, but not limited to: having a limited operating history and no products approved for commercial sale; having a history of significant losses; its need to obtain additional financing; dependence on its ability to advance its current and future product candidates through clinical trials, marketing approval and commercialization; the lengthy and expensive nature and uncertain outcomes of the clinical development process; the lengthy, time consuming and unpredictable nature of the regulatory approval process; the results of preclinical studies and early stage clinical trials that may not be predictive of future results; dependence on its key personnel; risks related to patent protection and the Company’s pending patent applications; dependence on third party collaborators for the discovery, development and commercialization of current and future product candidates; and significant competition from other biotechnology and pharmaceutical companies. Even if the Company’s development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

Note 11 - Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2023

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

	(000's)
Years ending December 31,
2024	$	1,264
2025		543
Total minimum lease payments		1,807
Less: amount of lease payments representing interest		(74	)
Present value of future minimum lease payments		1,733
Less: operating lease obligations, current portion		(1,197	)
Operating lease obligations, long-term portion	$	536

Insider Trading Arrangements	12 Months Ended	252 Months Ended
Insider Trading Arrangements	Dec. 31, 2023	Dec. 31, 2023
Insider Trading Arr Line Items
Material Terms of Trading Arrangement [Text Block]	Item 9B. Other Information. *Rule 10b5-1 Trading Plans* During the three months December 31, 2023, none of our directors or officers adopted, materially modified, or terminated any contract, instruction, or written plan for the purchase or sale our securities that was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act or any non-Rule 10b5-1 trading arrangement.
Rule 10b5-1 Arrangement Adopted [Flag]	false
Non-Rule 10b5-1 Arrangement Adopted [Flag]		false
Rule 10b5-1 Arrangement Terminated [Flag]	false
Non-Rule 10b5-1 Arrangement Terminated [Flag]	false

Note 14 - Subsequent Events

12 Months Ended

Dec. 31, 2023

Subsequent Events [Text Block]

14.

Subsequent Events

In the first quarter of 2024, the Company sold, through its Open Market Sale Agreement^SM with Jefferies LLC, 9,790,577 shares of common stock at an average price of $1.85 for total proceeds of $18.1 million and net proceeds of $17.6 million.

Document And Entity Information - USD ($) $ in Millions	12 Months Ended
Document And Entity Information - USD ($) $ in Millions	Dec. 31, 2023	Mar. 15, 2024	Jun. 30, 2023
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	000-55939
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 Street, 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 Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
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
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 283
Entity Common Stock, Shares Outstanding (in shares)		137,589,171
Auditor Firm ID	596
Auditor Name	CohnReznick LLP
Auditor Location	Melville, New York
Entity Central Index Key	0001738021
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Note 6 - Property and Equipment (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Depreciation, Total	$ 0.7	$ 0.8

Consolidated Balance Sheets (Parentheticals) - $ / shares shares in Thousands	Dec. 31, 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, Outstanding (in shares)	127,668	126,302
Common Stock, Shares, Issued (in shares)	127,668	126,495

Note 9 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
	Jan. 01, 2024	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2020
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 14,400
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 3.69
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value		$ 11	$ 6,300
The 2020 Stock Option and Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized				2,900
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		5,100
The 2020 Stock Option and Incentive Plan [Member] \| Subsequent Event [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	10,200
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	5,100
Restricted Stock [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		0	0
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 9,500
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 7 months 6 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		4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period		10 years
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 4,900
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		900	0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 7 months 6 days

Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating expenses:
Research and development	$ 38,120	$ 29,997
General and administrative	12,243	11,658
Total operating expenses	50,363	41,655
Loss from operations	(50,363)	(41,655)
Other income	7,869	2,430
Loss before income tax expense	(42,494)	(39,225)
Income tax expense	0	0
Net loss	$ (42,494)	$ (39,225)
Net loss per share - basic and diluted (in dollars per share)	$ (0.33)	$ (0.37)
Basic and diluted weighted average shares outstanding (in shares)	127,027	105,186
Other comprehensive loss:
Net loss	$ (42,494)	$ (39,225)
Unrealized gain (loss) on marketable securities	339	(302)
Comprehensive loss	$ (42,155)	$ (39,527)

Note 10 - License, Research and Collaboration Agreements (Details Textual) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2018	Dec. 31, 2023
ABL Bio Agreement [Member]
Upfront Payment	$ 5,000
License and Research Agreement, Future Payments	6,000
Milestone Payment Obligation	96,000
Maximum Development and Regulatory Milestone Payments	$ 303,000
Milestone Payments Paid		$ 110,000
ABL Bio Agreement [Member] \| Ophthalmology [Member]
Maximum Development and Regulatory Milestone Payments		75,000
Adimab Agreement [Member]
Milestone Payment Obligation		2,000
Milestone Payments Paid		$ 0

Note 6 - Property and Equipment

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment Disclosure [Text Block]

6.	Property and Equipment

Property and equipment consist of the following:

	December 31,
	2023			2022
	(000's)
Equipment	$	5,167		$	5,137
Furniture and fixtures		22			22
Leasehold improvements		1,612			1,612
Software		364			364
Total property and equipment–at cost		7,165			7,135
Less: Accumulated depreciation and amortization		(6,267	)		(5,568	)
Property and equipment, net	$	898		$	1,567

Total depreciation and amortization expense for years ended December 31, 2023 and 2022, was $0.7 million and $0.8 million, respectively.

Note 11 - Commitments and Contingencies - Undiscounted Cash Flows Reconciled to Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
2024	$ 1,264
2025	543
Total minimum lease payments	1,807
Less: amount of lease payments representing interest	(74)
Present value of future minimum lease payments	1,733
Less: operating lease obligations, current portion	(1,197)	$ (1,097)
Operating lease obligations, long-term portion	$ 536	$ 1,838

Note 10 - License, Research and Collaboration Agreements

12 Months Ended

Dec. 31, 2023

Collaborative Arrangement Disclosure [Text Block]

10.

License, Research and Collaboration Agreements

Collaboration Agreements

ABL Bio Corporation ("ABL Bio") Agreements

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, TRIGR 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 TRIGR.

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 December 31, 2023, future potential milestone payments in connection with this agreement amounted to $2.0 million.

Note 14 - Subsequent Events (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Proceeds from Issuance of Common Stock		$ 3,126	$ 76,237
Open Market Sale Agreement [Member] \| Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues	9,790,577
Shares Issued, Price Per Share	$ 1.85
Proceeds from Issuance of Common Stock	$ 18,100
Proceeds from Issuance of Common Stock, Net	$ 17,600

Note 6 - Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Table Text Block]

	December 31,
	2023			2022
	(000's)
Equipment	$	5,167		$	5,137
Furniture and fixtures		22			22
Leasehold improvements		1,612			1,612
Software		364			364
Total property and equipment–at cost		7,165			7,135
Less: Accumulated depreciation and amortization		(6,267	)		(5,568	)
Property and equipment, net	$	898		$	1,567

Note 5 - Marketable Securities - Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized Cost	$ 128,196	$ 151,965
Unrealized gains	147	64
Unrealized Losses	(110)	(366)
Fair Value	128,233	151,663
Marketable Securities	128,233	151,663
Corporate Debt Securities [Member]
Amortized Cost	54,256	87,998
Unrealized gains	74	12
Unrealized Losses	(49)	(250)
Fair Value	54,281	87,760
Marketable Securities	54,281	87,760
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized Cost	28,507	37,680
Unrealized gains	30	33
Unrealized Losses	(3)	(31)
Fair Value	28,534	37,682
Marketable Securities	28,534	37,682
Certificates of Deposit [Member]
Amortized Cost	18,850	19,689
Unrealized gains	17	16
Unrealized Losses	(1)	(38)
Fair Value	18,866	19,667
Marketable Securities	18,866	19,667
Asset-Backed Securities [Member]
Amortized Cost	10,456	6,598
Unrealized gains	23	3
Unrealized Losses	(7)	(47)
Fair Value	10,472	6,554
Marketable Securities	10,472	$ 6,554
US Treasury Securities [Member]
Amortized Cost	16,127
Unrealized gains	3
Unrealized Losses	(50)
Fair Value	16,080
Marketable Securities	$ 16,080

Note 7 - Accrued Expenses

12 Months Ended

Dec. 31, 2023

Accounts Payable and Accrued Liabilities Disclosure [Text Block]

7.	Accrued Expenses

Accrued expenses consist of the following:

	December 31,
	2023		2022
	(000's)
Project expenses	$	336	$	10,038
Compensation and benefits		1,938		1,556
Other		240		96
Total accrued expenses	$	2,514	$	11,690

Project expenses in 2022 were primarily made up of $8.8 million of accrued manufacturing expenses including $6.4 million of minimum contractual obligations which were paid in 2023.

Note 8 - Stockholders' Equity

12 Months Ended

Dec. 31, 2023

Equity [Text Block]

8.	Stockholders’ Equity

In November 2022, the Company sold through a Private Investment in Public Entity (“PIPE”) offering of 25,000,000 shares of our common stock at a purchase price of $3.21 per share. The gross proceeds to us from the PIPE were $80.3 million. In connection with the PIPE, the Company paid $4.5 million to the underwriters (and for other legal and accounting costs), for net proceeds of $75.7 million.

In June 2023, the Company sold, through its ATM program pursuant to its Open Market Sale Agreement^SM 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 in ATM offerings.

Basis of Accounting, Policy [Policy Text Block]

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (a)
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-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481004/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 6
-Subparagraph (a)
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-URI https://asc.fasb.org//1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

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

+ Details

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Basis of Presentation

Consolidation, Policy [Policy Text Block]

Principles of Consolidation

Use of Estimates, Policy [Policy Text Block]

Use of Estimates

Segment Reporting, Policy [Policy Text Block]

Segment Information

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash and Cash Equivalents

Marketable Securities, Policy [Policy Text Block]

Marketable Securities

Concentration Risk, Credit Risk, Policy [Policy Text Block]

Concentrations of Credit Risk

Property, Plant and Equipment, Policy [Policy Text Block]

Property and Equipment

Asset Classification	Estimated Useful Life
Equipment	5 years
Furniture and fixtures	7 years
Software	5 years
Leasehold improvements	Lesser of estimated useful life or lease term

Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]

Impairment of Long-Lived Assets

Fair Value Measurement, Policy [Policy Text Block]

Fair Value Measurements

●

Level 1 – Quoted prices in active markets for identical assets or liabilities.

●

Research and Development Expense, Policy [Policy Text Block]

Research and Development Costs

Accrued Research and Development Expenses [Policy Text Block]

Accrued Research and Development Expenses

Patents Costs [Policy Text Block]

Patent Costs

Share-Based Payment Arrangement [Policy Text Block]

Stock-Based Compensation

Expected volatility – The expected volatility is calculated based on the historical volatility of our common stock over the expected term of the option.

Risk-free interest rate – The risk-free rate assumption is based on U.S. Treasury instruments, the terms of which were consistent with the expected term of the Company’s equity award.

Expected dividend – The Company has not paid and does not intend to pay dividends.

Earnings Per Share, Policy [Policy Text Block]

Net Loss per Share

	December 31,
	2023		2022
	(000's)
Restricted stock units		1,500		900
Stock options		7,876		5,378
Nonvested restricted stock		—		193
Total		9,376		6,471

Income Tax, Policy [Policy Text Block]

Income Taxes

New Accounting Pronouncements, Policy [Policy Text Block]

New Accounting Pronouncements

Recently Adopted Accounting Pronouncements

There are no other pending accounting pronouncements that are expected to have a material impact on the Company’s consolidated financial statements.

Note 9 - Stock-based Compensation - Summary of RSU Activity (Details) - Restricted Stock Units (RSUs) [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Unvested, shares (in shares)	900	1,200
Unvested, estimated fair value per share (in dollars per share)	$ 3.83	$ 3.83
Granted, shares (in shares)	900	0
Granted, estimated fair value per share (in dollars per share)	$ 3.93	$ 0
Granted, weighted average fair value	$ 3,537	$ 0
Vested, shares (in shares)	(300)	(300)
Vested, estimated fair value per share (in dollars per share)	$ 3.83	$ 3.83
Vested, weighted average fair value	$ (1,149)	$ (1,149)
Forfeited or canceled, shares (in shares)	0	0
Forfeited or canceled, estimated fair value per share (in dollars per share)	$ 0	$ 0
Unvested, weighted average fair value	$ 5,745	$ 3,447
Unvested, shares (in shares)	1,500	900
Unvested, estimated fair value per share (in dollars per share)	$ 3.83	$ 3.83

Note 5 - Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2023

Marketable Securities [Table Text Block]

	Fair Value Measurements as of December 31, 2023 Using:
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	54,256	$	74	$	(49	)	$	54,281
Commercial paper		28,507		30		(3	)		28,534
Certificates of deposit		18,850		17		(1	)		18,866
U.S. government treasuries		16,127		3		(50	)		16,080
Asset-backed securities		10,456		23		(7	)		10,472
Total assets	$	128,196	$	147	$	(110	)	$	128,233

	Fair Value Measurements as of December 31, 2022 Using:
	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 December 31,
	2023		2022
Maturing in one year or less		93,117		134,620
Maturing after one year through two years		35,116		17,043
Total	$	128,233	$	151,663

Note 7 - Accrued Expenses (Details Textual) $ in Millions	Dec. 31, 2023 USD ($)
Accrued Manufacturing Expenses	$ 8.8
Manufacture and Purchase of CTX-009 [Member]
Contractual Obligation, Total	$ 6.4

Note 3 - Summary of Significant Accounting Policies - Schedule of Antidilutive Securities (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Potentially dilutive securities excluded from computation of diluted weighted average shares outstanding (in shares)	9,376	6,471
Restricted Stock Units (RSUs) [Member]
Potentially dilutive securities excluded from computation of diluted weighted average shares outstanding (in shares)	1,500	900
Share-Based Payment Arrangement, Option [Member]
Potentially dilutive securities excluded from computation of diluted weighted average shares outstanding (in shares)	7,876	5,378
Restricted Stock [Member]
Potentially dilutive securities excluded from computation of diluted weighted average shares outstanding (in shares)	0	193

Note 5 - Marketable Securities - Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Maturing in one year or less	$ 93,117	$ 134,620
Maturing after one year through two years	35,116	17,043
Total	$ 128,233	$ 151,663

Note 9 - Stock-based Compensation

12 Months Ended

Dec. 31, 2023