Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation: The accompanying consolidated financial statements have been prepared pursuant to the rules of the Securities and Exchange Commission (“SEC”) and in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The accompanying consolidated financial statements include the financial statements of Atossa Therapeutics, Inc. and its wholly-owned subsidiaries. All significant intercompany account balances and transactions have been eliminated in consolidation.
Use of Estimates, Policy [Policy Text Block]	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. Actual results could differ from those estimates.
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Adopted Accounting Pronouncements: On January 1, 2020, the Company adopted Accounting Standards Update ("ASU") No. 2018 - 13, Fair Value Measurement (Topic 820 ): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement , to improve the effectiveness of disclosures. The amendments remove, modify, and add certain disclosure requirements in Topic 820, “Fair Value Measurement.” The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. The adoption had no impact on the Company's consolidated financial statements. Recently Issued Accounting Pronouncements: In August 2020, the FASB issued ASU No. 2020 - 06, Accounting for Convertible Instruments and Contracts in an Entity's Own Equity Topic 815 which simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity's own equity. The guidance is effective for fiscal years beginning on or after December 15, 2023, with early adoption permitted, but not earlier than fiscal years beginning after December 15, 2020. The Company plans to implement this ASU effective January 1, 2021 using the modified retrospective approach. Upon adoption, the Company expects to record a cumulative adjustment to beginning stockholders' equity in the amount of $13,003,075 to reclassify the common stock warrant liability to Stockholders' Equity. In December 2019, the FASB issued ASU 2019 - 12, Income Taxes, (Topic 740 ): Simplifying the Accounting for Income Taxes , which amends the existing guidance relating to accounting for income taxes. This ASU is intended to simplify the accounting for income taxes by removing certain exceptions to the general principles of accounting for income taxes and to improve the consistent application of U.S. GAAP for other areas of accounting for income taxes by clarifying and amending existing guidance. This ASU is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. The Company does not expect that the adoptions of this new guidance will have a material effect on its consolidated financial statements.
Research and Development Expense, Policy [Policy Text Block]	Research and Development Research and development ("R&D") costs are generally expensed as incurred. R&D expenses include, for example, manufacturing expenses for the Company's drugs under development, expenses associated with clinical trials and associated salaries and benefits. R&D expenses also include an allocation of the CEO's salary and related benefits including bonus and non-cash stock-based compensation expense based on an estimate of total hours expended on research and development activities. The Company's CEO is involved in the development of the Company's drug candidates and oversight of the related clinical trial activity.
Income Tax, Policy [Policy Text Block]	Income Taxes The Company accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using enacted tax rates and laws that are expected to be in effect when the differences are expected to be recovered or settled. Realization of deferred tax assets is dependent upon future taxable income. A valuation allowance is recognized if it is more likely than not that some portion or all of a deferred tax asset will not be realized based on the weight of available evidence, including expected future earnings. The Company recognizes an uncertain tax position in its financial statements when it concludes that a tax position is more likely than not to be sustained upon examination based solely on its technical merits. Only after a tax position passes the first step of recognition will measurement be required. Under the measurement step, the tax benefit is measured as the largest amount of benefit that is more likely than not to be realized upon effective settlement. This is determined on a cumulative probability basis. The full impact of any change in recognition or measurement is reflected in the period in which such change occurs. The Company elects to accrue any interest or penalties related to income taxes as part of its income tax expense.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents Cash and cash equivalents include cash and all highly liquid instruments with original maturities of three months or less.
Property, Plant and Equipment, Policy [Policy Text Block]	Furniture and Equipment Furniture and equipment are stated at cost less accumulated depreciation. Expenditures for maintenance and repairs are charged to earnings as incurred; additions, renewals and betterments are capitalized. When furniture and equipment are retired or otherwise disposed of, the related cost and accumulated depreciation are removed from the respective accounts, and any gain or loss is included in operations. Depreciation is computed using the straight-line method over the estimated useful lives ranging from three to five years. Furniture and equipment amounted to $185,600 and $185,500 at December 31, 2020 and 2019, respectively. Accumulated depreciation was $165,000 and $151,200 at December 31, 2020 and 2019, respectively. Depreciation expense for the years ended December 31, 2020 and 2019 was $19,000 and $22,000, respectively. The Company periodically evaluates the carrying value of long-lived assets to be held and used and, if necessary, records impairment losses when indicators of impairment are present and the undiscounted cash flows estimated to be generated by those assets are less than the assets' carrying amounts. In that event, a loss is recognized based on the amount by which the carrying amount exceeds the fair market value of the long-loved assets. Loss on long-lived assets to be disposed of is determined in a similar manner, except that fair market values are reduced for the cost of disposal. For the years ended December 31, 2020 and 2019, no impairment of furniture and equipment was recorded.
Fair Value Measurement, Policy [Policy Text Block]	Fair Value Measurements The Company records financial assets and liabilities measured on a recurring and non-recurring basis as well as all non-financial assets and liabilities subject to fair value measurement at the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. These fair value principles prioritize valuation inputs across three broad levels. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the asset or liability, either directly or indirectly through market corroboration, for substantially the full term of the financial instrument. Level 3 inputs are unobservable inputs based on the Company's assumptions used to measure assets and liabilities at fair value. An asset or liability's classification within the various levels is determined based on the lowest level input that is significant to the fair value measurement. Also refer to Note 8.
Intangible Assets, Finite-Lived, Policy [Policy Text Block]	Intangible Assets Intangible assets consist of intellectual property and software acquired. Intangibles are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value of the assets might not be recoverable. Impairment losses must be recorded when indicators of impairment are present and the undiscounted cash flows estimated to be generated by those assets are less than the assets' carrying amounts. In that event, a loss is recognized based on the amount by which the carrying amount exceeds the fair market value of the assets. Estimating future cash flows related to an intangible asset involves significant estimates and assumptions. If our assumptions are not correct, there could be an impairment loss or, in the case of a change in the estimated useful life of the asset, a change in amortization expense. No impairment charges were recorded during the year ended December 31, 2020 or December 31, 2019. Amortization of intangible assets is computed using the straight-line method over the estimated useful lives ranging from three to ten years. Intangible assets amounted to $53,500 and $173,500 at December 31, 2020 and 2019, respectively. Accumulated amortization was $40,100 and $105,000 at December 31, 2020 and 2019, respectively. Amortization expense for the years ended December 31, 2020 and 2019 was $27,600 and $30,800, respectively.
Lessee, Leases [Policy Text Block]	Leases The Company evaluates all contractual agreements at inception to determine if they contain a lease. Lease liabilities are measured at present value of lease payments not yet paid, using a discounted cash flow model that requires the use of a discount rate, or incremental borrowing rate. The Company does not record right-of-use assets or operating lease liabilities on leases with initial terms of 12 months or less.
Share-based Payment Arrangement [Policy Text Block]	Stock-based Payments The Company measures and recognizes compensation expense for all stock-based payment awards made to employees, non-employee directors, and consultants, including employee stock options. Stock compensation expense is based on the estimated grant date fair value and is recognized as an expense over the requisite service period. The Company has made a policy election to recognize forfeitures when they occur. The fair value of each option grant is estimated using the Black-Scholes option-pricing model, which requires assumptions regarding the expected volatility of the stock options, the expected life of the options, an expectation regarding future dividends on the Company's common stock, and estimation of an appropriate risk-free interest rate. The Company's expected common stock price volatility assumption is based upon the historical volatility of our stock price. The Company has elected the simplified method for the expected life assumption for stock option grants, which averages the contractual term of the options of ten years with the vesting term, typically one to four years, as the Company does not have sufficient history of option exercise experience. The dividend yield assumption of zero is based upon the fact that the Company has never paid cash dividends and presently has no intention of paying cash dividends in the future. The risk-free interest rate used for each grant was based upon prevailing short-term interest rates over the expected life of the options.
Financial Instruments with Characteristics of Both Liabilities and Equity, Policy [Policy Text Block]	Financial Instruments with Characteristics of Both Liabilities and Equity During December 2020, the Company issued certain financial instruments, including warrants to purchase common stock, which have characteristics of both liability and equity. Financial instruments such as warrants that are classified as liabilities are fair valued upon issuance and are remeasured at fair value at subsequent reporting periods with the resulting change in fair value recorded in “change in fair value of common stock warrants”. The fair value of warrants is estimated using valuation models that require the input of subjective assumptions including stock price, exercise price, stock price volatility, expected life, an expectation regarding future dividends on the Company's common stock, and estimation of an appropriate risk-free interest rate.

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Basis of Accounting, Policy [Policy Text Block]

Basis of Presentation:

The accompanying consolidated financial statements have been prepared pursuant to the rules of the Securities and Exchange Commission (“SEC”) and in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The accompanying consolidated financial statements include the financial statements of Atossa Therapeutics, Inc. and its wholly-owned subsidiaries. All significant intercompany account balances and transactions have been eliminated in consolidation.

Use of Estimates, Policy [Policy Text Block]

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. Actual results could differ from those estimates.

New Accounting Pronouncements, Policy [Policy Text Block]

Recently Adopted Accounting Pronouncements:

January 1, 2020,

the Company adopted Accounting Standards Update ("ASU")

No.

2018

13,

Fair Value Measurement (Topic

820

): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement

, to improve the effectiveness of disclosures. The amendments remove, modify, and add certain disclosure requirements in Topic

820,

“Fair Value Measurement.” The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level

fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. The adoption had

impact on the Company's consolidated financial statements.

Recently Issued Accounting Pronouncements:

August

2020,

the FASB issued ASU

No.

2020

06,

Accounting for Convertible Instruments and Contracts in an Entity's Own Equity

Topic

815

which simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity's own equity. The guidance is effective for fiscal years beginning on or after

December 15, 2023,

with early adoption permitted, but

not

earlier than fiscal years beginning after

December 15, 2020.

The Company plans to implement this ASU effective

January 1, 2021

using the modified retrospective approach. Upon adoption, the Company expects to record a cumulative adjustment to beginning stockholders' equity in the amount of

$13,003,075

to reclassify the common stock warrant liability to Stockholders' Equity.

December 2019,

the FASB issued ASU

2019

12,

Income Taxes, (Topic

740

): Simplifying the Accounting for Income Taxes

, which amends the existing guidance relating to accounting for income taxes. This ASU is intended to simplify the accounting for income taxes by removing certain exceptions to the general principles of accounting for income taxes and to improve the consistent application of U.S. GAAP for other areas of accounting for income taxes by clarifying and amending existing guidance. This ASU is effective for fiscal years beginning after

December 15, 2020,

with early adoption permitted. The Company does

not

expect that the adoptions of this new guidance will have a material effect on its consolidated financial statements.

Research and Development Expense, Policy [Policy Text Block]

Research and Development

Research and development ("R&D") costs are generally expensed as incurred. R&D expenses include, for example, manufacturing expenses for the Company's drugs under development, expenses associated with clinical trials and associated salaries and benefits. R&D expenses also include an allocation of the CEO's salary and related benefits including bonus and non-cash stock-based compensation expense based on an estimate of total hours expended on research and development activities. The Company's CEO is involved in the development of the Company's drug candidates and oversight of the related clinical trial activity.

Income Tax, Policy [Policy Text Block]

Income Taxes

The Company accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using enacted tax rates and laws that are expected to be in effect when the differences are expected to be recovered or settled. Realization of deferred tax assets is dependent upon future taxable income. A valuation allowance is recognized if it is more likely than

not

that some portion or all of a deferred tax asset will

not

be realized based on the weight of available evidence, including expected future earnings. The Company recognizes an uncertain tax position in its financial statements when it concludes that a tax position is more likely than

not

to be sustained upon examination based solely on its technical merits. Only after a tax position passes the

first

step of recognition will measurement be required. Under the measurement step, the tax benefit is measured as the largest amount of benefit that is more likely than

not

to be realized upon effective settlement. This is determined on a cumulative probability basis. The full impact of any change in recognition or measurement is reflected in the period in which such change occurs. The Company elects to accrue any interest or penalties related to income taxes as part of its income tax expense.

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash and Cash Equivalents

Cash and cash equivalents include cash and all highly liquid instruments with original maturities of

three

months or less.

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

Furniture and Equipment

Furniture and equipment are stated at cost less accumulated depreciation. Expenditures for maintenance and repairs are charged to earnings as incurred; additions, renewals and betterments are capitalized. When furniture and equipment are retired or otherwise disposed of, the related cost and accumulated depreciation are removed from the respective accounts, and any gain or loss is included in operations.

Depreciation is computed using the straight-line method over the estimated useful lives ranging from

three

five

years.

Furniture and equipment amounted to

$185,600

and

$185,500

December 31, 2020

and

2019,

respectively. Accumulated depreciation was

$165,000

and

$151,200

December 31, 2020

and

2019,

respectively. Depreciation expense for the years ended

December 31, 2020

and

2019

was

$19,000

and

$22,000,

respectively.

The Company periodically evaluates the carrying value of long-lived assets to be held and used and, if necessary, records impairment losses when indicators of impairment are present and the undiscounted cash flows estimated to be generated by those assets are less than the assets' carrying amounts. In that event, a loss is recognized based on the amount by which the carrying amount exceeds the fair market value of the long-loved assets. Loss on long-lived assets to be disposed of is determined in a similar manner, except that fair market values are reduced for the cost of disposal. For the years ended

December 31, 2020

and

2019,

impairment of furniture and equipment was recorded.

Fair Value Measurement, Policy [Policy Text Block]

Fair Value Measurements

The Company records financial assets and liabilities measured on a recurring and non-recurring basis as well as all non-financial assets and liabilities subject to fair value measurement at the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. These fair value principles prioritize valuation inputs across

three

broad levels. Level

inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level

inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the asset or liability, either directly or indirectly through market corroboration, for substantially the full term of the financial instrument. Level

inputs are unobservable inputs based on the Company's assumptions used to measure assets and liabilities at fair value. An asset or liability's classification within the various levels is determined based on the lowest level input that is significant to the fair value measurement. Also refer to Note

Intangible Assets, Finite-Lived, Policy [Policy Text Block]

Intangible Assets

Intangible assets consist of intellectual property and software acquired. Intangibles are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value of the assets might

not

be recoverable. Impairment losses must be recorded when indicators of impairment are present and the undiscounted cash flows estimated to be generated by those assets are less than the assets' carrying amounts. In that event, a loss is recognized based on the amount by which the carrying amount exceeds the fair market value of the assets. Estimating future cash flows related to an intangible asset involves significant estimates and assumptions. If our assumptions are

not

correct, there could be an impairment loss or, in the case of a change in the estimated useful life of the asset, a change in amortization expense.

impairment charges were recorded during the year ended

December 31, 2020

December 31, 2019.

Amortization of intangible assets is computed using the straight-line method over the estimated useful lives ranging from

three

ten

years.

Intangible assets amounted to

$53,500

and

$173,500

December 31, 2020

and

2019,

respectively. Accumulated amortization was

$40,100

and

$105,000

December 31, 2020

and

2019,

respectively. Amortization expense for the years ended

December 31, 2020

and

2019

was

$27,600

and

$30,800,

respectively.

Lessee, Leases [Policy Text Block]

Leases

The Company evaluates all contractual agreements at inception to determine if they contain a lease. Lease liabilities are measured at present value of lease payments

not

yet paid, using a discounted cash flow model that requires the use of a discount rate, or incremental borrowing rate. The Company does

not

record right-of-use assets or operating lease liabilities on leases with initial terms of

months or less.

Share-based Payment Arrangement [Policy Text Block]

Stock-based Payments

The Company measures and recognizes compensation expense for all stock-based payment awards made to employees, non-employee directors, and consultants, including employee stock options. Stock compensation expense is based on the estimated grant date fair value and is recognized as an expense over the requisite service period. The Company has made a policy election to recognize forfeitures when they occur.

The fair value of each option grant is estimated using the Black-Scholes option-pricing model, which requires assumptions regarding the expected volatility of the stock options, the expected life of the options, an expectation regarding future dividends on the Company's common stock, and estimation of an appropriate risk-free interest rate. The Company's expected common stock price volatility assumption is based upon the historical volatility of our stock price. The Company has elected the simplified method for the expected life assumption for stock option grants, which averages the contractual term of the options of

ten

years with the vesting term, typically

one

four

years, as the Company does

not

have sufficient history of option exercise experience. The dividend yield assumption of

zero

is based upon the fact that the Company has never paid cash dividends and presently has

intention of paying cash dividends in the future. The risk-free interest rate used for each grant was based upon prevailing short-term interest rates over the expected life of the options.

Financial Instruments with Characteristics of Both Liabilities and Equity, Policy [Policy Text Block]

Financial Instruments with Characteristics of Both Liabilities and Equity

During

December 2020,

the Company issued certain financial instruments, including warrants to purchase common stock, which have characteristics of both liability and equity. Financial instruments such as warrants that are classified as liabilities are fair valued upon issuance and are remeasured at fair value at subsequent reporting periods with the resulting change in fair value recorded in “change in fair value of common stock warrants”. The fair value of warrants is estimated using valuation models that require the input of subjective assumptions including stock price, exercise price, stock price volatility, expected life, an expectation regarding future dividends on the Company's common stock, and estimation of an appropriate risk-free interest rate.