Liquidia (LQDA) 10-Q 13 May 21 2021 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2021	May 04, 2021
Document Information [Line Items]
Entity Central Index Key	0001819576
Entity Registrant Name	LIQUIDIA CORPORATION
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2021
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-39724
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	85-1710962
Entity Address, Address Line One	419 Davis Drive, Suite 100
Entity Address, City or Town	Morrisville
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27560
City Area Code	919
Local Phone Number	328-4400
Title of 12(b) Security	Common stock, $0.001 par value per share
Trading Symbol	LQDA
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		51,972,961

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 53,637,155	$ 65,316,481
Accounts receivable, net	627,600	0
Prepaid expenses and other current assets	814,046	752,447
Total current assets	55,078,801	66,068,928
Property, plant and equipment, net	6,296,068	6,805,570
Operating lease right-of-use assets, net	2,596,305	2,649,328
Indemnification asset, related party	2,985,461	1,387,275
Contract acquisition costs, net	12,034,436	12,792,491
Intangible asset, net	5,206,625	5,534,843
Goodwill	3,903,282	3,903,282
Other assets	350,896	390,043
Total assets	88,451,874	99,531,760
Current liabilities:
Accounts payable	3,004,002	3,734,227
Accrued compensation	1,487,190	3,259,515
Other accrued expenses	2,367,197	1,386,880
Refund liability	0	1,768,864
Current portion of operating lease liabilities	691,103	664,670
Current portion of finance lease liabilities	333,365	923,218
Total current liabilities	7,882,857	11,737,374
Litigation finance payable	2,081,272	1,154,360
Long-term operating lease liabilities	4,821,539	5,006,301
Long-term finance lease liabilities	580,546	255,402
Long-term debt	10,176,481	10,292,485
Total liabilities	25,542,695	28,445,922
Commitments and contingencies
Stockholders' equity:
Preferred stock - 10,000,000 shares authorized as of March 31, 2021 and December 31, 2020, 0 shares issued and outstanding as of March 31, 2021 and December 31, 2020	0	0
Common stock - $0.001 par value, 80,000,000 shares authorized as of March 31, 2021 and December 31, 2020, 43,346,924 and 43,336,277 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	43,347	43,336
Additional paid-in capital	347,051,204	346,044,721
Accumulated deficit	(284,185,372)	(275,002,219)
Total stockholders' equity	62,909,179	71,085,838
Total liabilities and stockholders' equity	$ 88,451,874	$ 99,531,760

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Consolidated Balance Sheets
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	80,000,000	80,000,000
Common stock, shares issued (in shares)	43,346,924	43,336,277
Common stock, shares outstanding (in shares)	43,346,924	43,336,277

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Consolidated Statements of Operations and Comprehensive Loss
Revenue	$ 3,083,631	$ 0
Costs and expenses:
Costs and expenses	693,735	0
Research and development	6,053,726	10,822,924
General and administrative	5,337,253	3,823,197
Total costs and expenses	12,084,714	14,646,121
Loss from operations	(9,001,083)	(14,646,121)
Other income (expense):
Interest income	20,766	109,590
Interest expense	(202,836)	(254,948)
Total other expense, net	(182,070)	(145,358)
Net loss and comprehensive loss	$ (9,183,153)	$ (14,791,479)
Net loss per common share, basic and diluted	$ (0.21)	$ (0.52)
Weighted average common shares outstanding, basic and diluted	43,443,361	28,428,616

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2019	28,231,267
Balance at Dec. 31, 2019	$ 28,231	$ 250,158,766	$ (215,239,450)	$ 34,947,547
Exercise of common stock options (in shares)	2,035
Exercise of common stock options	$ 2	(2)	0	0
Stock-based compensation	0	878,963	0	878,963
Net loss	$ 0	0	(14,791,479)	(14,791,479)
Issuance of common stock under employee stock purchase plan (in shares)	3,269
Issuance of common stock under employee stock purchase plan	$ 3	11,488	0	11,491
Issuance of common stock under stock incentive plan (in shares)	702
Issuance of common stock under stock incentive plan	$ 1	(1)	0	0
Sale of common stock, net (in shares)	131,425
Sale of common stock, net	$ 131	725,267	0	725,398
Balance (in shares) at Mar. 31, 2020	28,368,698
Balance at Mar. 31, 2020	$ 28,368	251,774,481	(230,030,929)	21,771,920
Balance (in shares) at Dec. 31, 2020	43,336,277
Balance at Dec. 31, 2020	$ 43,336	346,044,721	(275,002,219)	$ 71,085,838
Exercise of common stock options (in shares)	281			623
Exercise of common stock options	$ 0	494	0	$ 494
Issuance of common stock under vesting of restricted stock units (in shares)	10,366
Issuance of common stock under vesting of restricted stock units	$ 11	(11)	0	0
Issuance of warrants	0	261,000	0	261,000
Stock-based compensation	0	745,000	0	745,000
Net loss	$ 0	0	(9,183,153)	(9,183,153)
Balance (in shares) at Mar. 31, 2021	43,346,924
Balance at Mar. 31, 2021	$ 43,347	$ 347,051,204	$ (284,185,372)	$ 62,909,179

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net loss	$ (9,183,153)	$ (14,791,479)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation	745,000	878,963
Depreciation and amortization	1,609,409	732,029
Non-cash lease expense	53,023	38,192
Non-cash interest expense	124,178	19,158
Changes in operating assets and liabilities, net of business acquired:
Accounts receivable, net	(627,600)	0
Prepaid expenses and other current assets	(61,599)	(294,672)
Other non-current assets	39,147	(3,000)
Accounts payable	(2,328,411)	2,205,615
Accrued compensation	(1,772,325)	(1,736,417)
Other accrued expenses	943,804	(1,351,560)
Refund liability	(1,768,864)	0
Operating lease liabilities	(158,329)	(134,945)
Net cash used in operating activities	(12,385,720)	(14,438,116)
Investing activities
Purchases of property, plant and equipment	(52,419)	(182,216)
Net cash used in investing activities	(52,419)	(182,216)
Financing activities
Principal payments on finance leases	(225,922)	(304,285)
Proceeds from issuance of long-term debt with warrants, net	10,410,269	0
Principal payments on long-term debt	(10,352,940)	(1,411,766)
Receipts from litigation financing	926,912	0
Proceeds from sale of common stock, net of underwriting fees and commissions	0	725,398
Payments for offering costs	0	(68,965)
Proceeds from issuance of common stock under stock incentive plans	494	11,491
Net cash provided by (used in) financing activities	758,813	(1,048,127)
Net decrease in cash and cash equivalents	(11,679,326)	(15,668,459)
Cash and cash equivalents, beginning of period	65,316,481	55,796,378
Cash and cash equivalents, end of period	53,637,155	40,127,919
Supplemental disclosure of cash flow information
Cash paid for interest	87,320	241,804
Cash paid for operating lease liabilities	300,424	291,743
Reduction of lease liability and right of use asset from lease modification	38,787	0
Non-cash increase in indemnification asset through accounts payable	1,598,186	0
Changes in purchases of property, plant and equipment in accounts payable and accrued expenses	$ 0	$ 104,167

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Basis of Presentation and Summary of Significant Accounting Policies
Basis of Presentation and Summary of Significant Accounting Policies	2. Basis of Presentation, Significant Accounting Policies and Fair Value Measurements Basis of Presentation The unaudited interim condensed consolidated financial statements as of March 31, 2021 and for the three months ended March 31, 2021 and 2020 have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial reporting. These condensed consolidated financial statements are unaudited and, in the opinion of management, include all adjustments (consisting only of normal recurring adjustments and accruals) necessary for a fair statement of the results for the periods presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The year-end condensed consolidated balance sheet data was derived from the Company’s audited consolidated financial statements but does not include all disclosures required by GAAP. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2021. Certain information and footnote disclosures normally included in the annual consolidated financial statements prepared in accordance with GAAP have been omitted in accordance with the SEC’s rules and regulations for interim reporting. The Company’s financial position, results of operations and cash flows are presented in U.S. Dollars. The accompanying unaudited condensed consolidated financial statements and related notes should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2020, which are included in the Company’s 2020 Annual Report on Form 10-K. There have been no material changes to the Company’s significant accounting policies during the three months ended March 31, 2021 compared with the significant accounting policies disclosed in Note 2 of the consolidated financial statements for the years ended December 31, 2020 and 2019, which are included in the Company’s 2020 Annual Report on Form 10-K. Consolidation The accompanying condensed consolidated financial statements include the Company’s wholly owned subsidiaries, Liquidia Technologies and Liquidia PAH. All intercompany accounts and transactions have been eliminated. Use of Estimates The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities, at the date of the financial statements, as well as the reported amounts of revenues and expenses during the period. These estimates are based on historical experience and various other assumptions believed reasonable under the circumstances. The Company evaluates its estimates on an ongoing basis and makes changes to the estimates and related disclosures as experience develops or new information becomes known. Actual results will most likely differ from those estimates. Revision of Previously Issued Financial Statements During the three months ended June 30, 2020, the Company identified an error in the matter in which it calculated diluted weighted common shares outstanding and diluted net loss per common share. While the Company has included common stock warrants whose exercise price is de minimis in the calculation of basic weighted average common shares outstanding and basic net loss per common share, these warrants were inappropriately excluded from the calculation of diluted weighted average common shares outstanding and diluted net loss per common share, which resulted in an error in diluted weighted average common shares outstanding for the three month period ended March 31, 2020. The Company has evaluated this error and determined that this presentation error was not material to any prior annual or interim periods. However, the Company is revising the previously presented March 31, 2020 diluted weighted common shares outstanding as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, 2020 ​ As Presented As Revised Diluted weighted average shares outstanding ​ 28,322,342 ​ 28,428,616 ​ Summary of Significant Accounting Policies Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents as of March 31, 2021 were $53.6 million and included cash investments in money market funds of $42.7 million. Cash as of December 31, 2020 was $65.3 million and included no cash equivalents. Accounts Receivable Accounts receivable are stated at net realizable value including an allowance for doubtful accounts as of each balance sheet date, if applicable. As of March 31, 2021 and December 31, 2020, the Company has not recorded an allowance for doubtful accounts. Business Combination In a business combination, the acquisition method of accounting requires that the assets acquired and liabilities assumed be recorded as of the date of the acquisition at their respective fair values with limited exceptions. Assets acquired and liabilities assumed in a business combination that arise from contingencies are generally recognized at fair value. If fair value cannot be determined, the asset or liability is recognized if probable and reasonably estimable; if these criteria are not met, no asset or liability is recognized. Transaction costs and costs to restructure the acquired company are expensed as incurred. The operating results of the acquired business are reflected in the Company’s consolidated financial statements after the date of the acquisition. Long-Lived Assets The Company reviews long-lived assets, including definite-life intangible assets, for realizability on an ongoing basis. Changes in depreciation and amortization, generally accelerated depreciation and variable amortization, are determined and recorded when estimates of the remaining useful lives or residual values of long-term assets change. The Company also reviews for impairment when conditions exist that indicate the carrying amount of the assets may not be fully recoverable. In those circumstances, the Company performs undiscounted operating cash flow analyses to determine if an impairment exists. When testing for asset impairment, the Company groups assets and liabilities at the lowest level for which cash flows are separately identifiable. Any impairment loss is calculated as the excess of the asset’s carrying value over its estimated fair value. Fair value is estimated based on the discounted cash flows for the asset group over the remaining useful life or based on the expected cash proceeds for the asset less costs of disposal. Any impairment losses would be recorded in the consolidated statements of operations. To date, no such impairments have occurred. Goodwill The Company acquired goodwill on its condensed consolidated balance sheet during the fourth quarter of 2020 from the Merger Transaction. The Company assesses goodwill for impairment at least annually as of July 1 or whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. The Company has one reporting unit. The Company has the option to first assess qualitative factors to determine whether events or circumstances indicate it is more likely than not that the fair value of a reporting unit is greater than its carrying amount, in which case a quantitative impairment test is not required. Per ASU 2017-04 the quantitative goodwill impairment test is performed by comparing the fair value of the reporting unit with its carrying amount, including goodwill. If the fair value of the reporting unit exceeds its carrying amount, goodwill is not impaired. An impairment loss is recognized for any excess of the carrying amount of the reporting unit’s goodwill over the fair value up to the amount of goodwill allocated to the reporting unit. Income tax effects from any tax-deductible goodwill on the carrying amount of the reporting unit are considered when measuring the goodwill impairment loss, if applicable. To date, no such impairments have occurred. Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash and cash equivalents. The Company is exposed to credit risk, subject to federal deposit insurance, in the event of default by the financial institutions holding its cash and cash equivalents to the extent of amounts recorded on the condensed consolidated balance sheet. 81.5% of the Company’s cash and cash equivalents are held with Silicon Valley Bank (“SVB”). As of and for the three months ended March 31, 2021, one customer accounted for all of the Company's accounts receivable and revenue. Revenue Recognition The Company recognizes revenue in accordance with Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers (Topic 606). The core principle of Topic 606 is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. The following five steps are applied to achieve that core principle: ● Step 1: Identify the contract with the customer ● Step 2: Identify the performance obligations in the contract ● Step 3: Determine the transaction price ● Step 4: Allocate the transaction price to the performance obligations in the contract ● Step 5: Recognize revenue when the company satisfies a performance obligation In order to identify the performance obligations in a contract with a customer, the Company assesses the promised goods or services in the contract and identifies each promised good or service that is distinct. If a good or service is not distinct, the good or service is combined with other promised goods or services until a bundle of goods or services is identified that is distinct. The transaction price is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer. The consideration promised in a contract with a customer may include fixed amounts, variable amounts, or both. Variable consideration is included in the transaction price only to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. The Company evaluates any non-cash consideration, consideration payable to the customer, potential returns and refunds, and whether consideration contains a significant financing element in determining the transaction price. Revenue is measured based on consideration specified in a contract with a customer. The Company recognizes revenue when it satisfies a performance obligation by transferring control over a service to a customer. The amount of revenue recognized reflects estimates for refunds and returns, which are presented as a reduction of Accounts receivable where the right of setoff exists. Stock-Based Compensation The Company estimates the grant date fair value of its stock-based awards and amortizes this fair value to compensation expense on a straight-line basis over the requisite service period, which is generally the vesting period of the respective award (see Note 5). The grant date fair value of stock options is determined using the Black-Scholes option-pricing model. Net Loss Per Share Basic net loss per share is calculated by dividing net loss attributable to common stockholders by the weighted average shares outstanding during the period, without consideration of common stock equivalents. Diluted net loss per share is calculated by adjusting the weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. For purposes of the diluted net loss per share calculation, stock options, restricted stock units and the SVB Warrant (see Note 11) are considered to be common stock equivalents but are excluded from the calculation of diluted net loss per share because their effect would be anti-dilutive. Due to their anti-dilutive effect, the calculation of diluted net loss per share for the three months ended March 31, 2021 and 2020 does not include the following common stock equivalent shares: ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ ​ ​ 2021 ​ 2020 ​ Stock Options 4,776,022 2,119,523 ​ Restricted Stock Units 313,099 48,759 ​ SVB Warrant ​ 36,667 ​ — ​ Total 5,125,788 2,168,282 ​ ​ For the three months ended March 31, 2021 and 2020, certain common stock warrants are included in the calculation of basic and diluted net loss per share since their exercise price is de minimis. Recent Accounting Pronouncements In March 2020, the Financial Accounting Standards Board ("FASB") issued guidance that provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by the discontinuation of the London Interbank Offered Rate (“LIBOR”) or by another reference rate expected to be discontinued. The Company adopted this guidance during the first quarter of 2021 and it did not have a material impact on its consolidated financial position, results of operations or cash flows. In August 2020, the FASB issued ASU 2020-06, Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity Fair Value of Measurements The Company’s valuation of financial instruments is based on a three-tiered approach, which requires that fair value measurements be classified and disclosed in one of three tiers. The fair value hierarchy defines a three-level valuation hierarchy for disclosure of fair value measurements as follows: Level 1 — Quoted prices in active markets for identical assets or liabilities; Level 2 — Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly; and Level 3 — Unobservable inputs for the asset and liability used to measure fair value, to the extent that observable inputs are not available. The categorization of a financial instrument within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The following tables present the placement in the fair value hierarchy of financial liabilities measured at fair value as of March 31, 2021 and December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying March 31, 2021 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market mutual funds ​ $ 42,726,954 ​ $ — ​ $ — ​ $ 42,726,954 Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Silicon Valley Bank term loan ​ $ — ​ $ 10,072,320 ​ $ — ​ $ 10,176,481 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2020 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pacific Western Bank term loan ​ $ — ​ $ 9,842,069 ​ $ — ​ $ 10,292,485 ​ Money market mutual funds are included in cash and cash equivalents on the Company's condensed consolidated balance sheets. They are valued using quoted market prices and therefore are classified within Level 1 of the fair value hierarchy. The carrying amounts reflected in the Company's condensed consolidated balance sheets for cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued expenses and other liabilities approximate their fair values due to their short-term nature. The fair value of debt is measured in accordance with ASU 2016-01, Financial Instruments–Overall: Recognition and Measurement of Financial Assets and Financial Liabilities

Acquisition of RareGen LLC (now

Acquisition of RareGen LLC (now Liquidia PAH, LLC)	3 Months Ended
	Mar. 31, 2021
Acquisition of RareGen LLC (now Liquidia PAH, LLC)
Acquisition of RareGen LLC (now Liquidia PAH, LLC)	3. Acquisition of RareGen LLC (now Liquidia PAH, LLC) ​ On November 18, 2020 (the “Closing Date”), the Company completed the previously announced acquisition contemplated by the Agreement and Plan of Merger, dated as of June 29, 2020, as amended by a Limited Waiver and Modification to the Merger Agreement, dated as of August 3, 2020 (the “Merger Agreement”), by and among Liquidia Technologies, the Company, RareGen, Gemini Merger Sub I, Inc., a Delaware corporation (“Liquidia Merger Sub”), Gemini Merger Sub II, LLC, a Delaware limited liability company (“RareGen Merger Sub”), and PBM RG Holdings, LLC, a Delaware limited liability company (“PBM”). Pursuant to the Merger Agreement, Liquidia Merger Sub, a former wholly owned subsidiary of the Company, merged with and into Liquidia Technologies (the “Liquidia Technologies Merger”), and RareGen Merger Sub, a former wholly owned subsidiary of the Company, merged with and into RareGen (the “RareGen Merger” and, together with the Liquidia Technologies Merger, the “Merger Transaction”). Upon consummation of the Merger Transaction, the separate corporate existences of Liquidia Merger Sub and RareGen Merger Sub ceased and Liquidia Technologies and RareGen (now Liquidia PAH) continue as wholly owned subsidiaries of Liquidia Corporation. On the Closing Date, an aggregate of 5,550,000 shares of common stock, $0.001 par value per share (“Liquidia Corporation Common Stock”), were issued to RareGen members in exchange for 10,000 RareGen common units, representing all of the issued and outstanding RareGen equity. Additionally, on the Closing Date, an aggregate of 616,666 shares of Liquidia Corporation Common Stock were withheld from RareGen members to secure the indemnification obligations of RareGen members. Additionally, RareGen members received a pro rata portion of the RareGen cash at closing in excess of $1 million. RareGen members are also entitled to receive a pro rata portion of up to an additional 2,708,333 shares of Liquidia Corporation Common Stock in the aggregate in 2022, based on the amount of 2021 net sales of the generic treprostinil product (“Net Sales Earnout Shares”) owned by Sandoz, which RareGen markets pursuant to the Promotion Agreement. The fair value of the purchase consideration or the purchase price was approximately $20.8 million. Reasons for the Acquisition and Merger The Company acquired Liquidia PAH to improve financial strength and operational efficiencies including the generation of cash flow through sales of a generic version of Remodulin, which is a parenteral formulation of treprostinil, for the treatment of PAH. Strategically, the Company believes that its commercial presence in the field will enable an efficient launch of LIQ861 upon approval, leveraging existing relationships and further validating its reputation as a company committed to supporting PAH patients. Merger Consideration The fair value of the purchase consideration or the purchase price, was approximately $20.8 million. The purchase consideration consisted of the 6,166,666 shares of Liquidia Corporation Common Stock at a per share price of $3.38, which represented the closing price of Liquidia Technologies Common Stock on the Closing Date. 5,550,000 of the shares were issued as of December 31, 2020 and the remaining 616,666 shares were withheld from RareGen members to secure their indemnification obligations pursuant to the Merger Agreement. The total purchase price and allocated purchase price is summarized as follows: ​ ​ ​ ​ ​ Number of common shares to be issued to RareGen’s members ​ 6,166,666 Multiplied by the fair value per share of Liquidia Technologies common stock ​ $ 3.38 Total estimated purchase price ​ $ 20,843,331 ​ Accounting for the Acquisition The acquisition of Liquidia PAH was accounted for as a business combination and reflects the application of acquisition accounting in accordance with Accounting Standards Codification (ASC) 805, Business Combinations. The acquired Liquidia PAH assets, including identifiable intangible assets and liabilities assumed, have been recorded at their estimated fair values with the excess purchase price assigned to goodwill. A preliminary purchase price allocation has been performed and the recorded amounts for intangible assets, other assets, indemnification asset, goodwill, litigation finance payable, deferred tax liability and other liabilities are subject to change pending finalization of valuation efforts and review of tax matters. The amounts recognized will be finalized as the information necessary to complete the analysis is obtained, but no later than one year after the Closing Date. Purchase Price Allocation The preliminary purchase price allocation resulted in the following amounts being allocated to the assets acquired and liabilities assumed as of the Closing Date of November 18, 2020 based on their respective preliminary fair values summarized below: ​ ​ ​ ​ ​ Cash $ 1,000,000 Property and equipment ​ 79,330 Prepaid and other current assets ​ 30,190 Intangible asset ​ 5,620,000 Contract acquisition costs ​ 12,980,000 Indemnification asset, related party ​ 1,065,538 Goodwill ​ 3,903,282 Less other current liabilities ​ (492,499) Less refund liability ​ (2,696,000) Less litigation finance payable, long-term ​ (646,510) Total estimated purchase price ​ $ 20,843,331 ​ Contract Acquisition Costs, Intangible Asset and Goodwill Acquired Prior to the Merger Transaction, the Company did not have contract acquisition costs, intangible assets or goodwill on its balance sheet. Contract acquisition costs and Intangible asset of $12,980,000 and $5,620,000, respectively, were acquired in the Merger Transaction relating to and consisting of the Promotion Agreement. The Company is amortizing the value of the Promotion Agreement contract acquisition costs and intangible asset on a pro-rata basis based on the estimated total revenue or net profits to be recognized over the period from the date of the Merger Transaction through May 2027 (see Note 2 for Revenue Recognition accounting policy). Amortization of contract acquisition costs is recorded as a reduction of revenue and amortization of the intangible asset is recorded as cost of revenue. During the three months ended March 31, 2021, the Company recorded total amortization of $758,056 from the contract acquisition costs as a reduction in revenue. Net contract acquisition costs totaled $12,034,436 and $12,792,491 as of March 31, 2021 and December 31, 2020. During the three months ended March 31, 2021, the Company recorded total amortization of $328,218 from the intangible asset as cost of revenue. The Company acquired goodwill in the Merger Transaction of $3,903,282 which primarily represents the Liquidia PAH assembled workforce and the residual value of the purchase consideration and assumed liabilities that exceeded the assets acquired (see Note 2 for Goodwill accounting policy). None of the goodwill recognized is expected to be deductible for income tax purposes. Refund Liability In accordance with the Promotion Agreement, Liquidia PAH receives consideration from Sandoz in the form of a share of Net Profits for the promotional activities it performs. The share of Net Profits received is subject to adjustments from Sandoz for items such as distributor chargebacks, rebates, inventory returns, inventory write-offs and other adjustments (the “Net Profits Adjustment”). As of the date of the Merger Transaction, the Company identified approximately $2,696,000 of Net Profits Adjustment that are expected to be refunded to Sandoz during 2021 for items that had been incurred prior to the Merger Transaction. The Company has recorded a refund liability as part of the assumed liabilities from the Merger Transaction. The Company expects to refund this amount to Sandoz through a reduction of the cash received from future Net Profits generated under the Promotion Agreement. The Company expects to generate sufficient Net Profits during 2021 to satisfy the refund liability. As of March 31, 2021, $826,468 of refund liability is offset against Accounts receivable from Sandoz related to net service revenues recognized during the first quarter of 2021. As of December 31, 2020 Indemnification Asset with Related Party and Litigation Finance Payable Prior to the Closing Date of the Merger Transaction, Liquidia PAH entered into a litigation financing arrangement (the “Financing Agreement”) with Henderson SPV, LLC (“Henderson”). Liquidia PAH, along with Sandoz (collectively the “Plaintiffs”), are pursuing litigation against United Therapeutics Corporation (“United Therapeutics”) and, prior to entering into a binding settlement term sheet with Smiths Medical ASC in November 2020, were pursuing litigation against Smiths. Under the Financing Agreement, Henderson will fund Liquidia PAH’s legal and litigation expenses (referred to as “Deployments”) in exchange for a share of certain litigation or settlement proceeds. Deployments received from Henderson are recorded as a Litigation finance payable. Litigation proceeds will be split equally between Liquidia PAH and Sandoz. Unless there is an event of default by Henderson, litigation proceeds received by Liquidia PAH must be applied first to repayment of total Deployments received. Litigation proceeds in excess of Deployments received are split between Liquidia PAH and Henderson according to a formula. Unless there is an event of default by PBM, proceeds received by Liquidia PAH are due to PBM as described further below. In connection with the Merger Transaction, Liquidia PAH entered into a Litigation Funding and Indemnification Agreement (“Indemnification Agreement”) with PBM. PBM is considered to be a related party as it is controlled by a major stockholder (which beneficially owns approximately 10% of Liquidia Corporation Common Stock as of April 15, 2021) who is also a member of the Company’s Board of Directors. Prior to the Merger Transaction, Liquidia PAH was actively managing the litigation, and had sole decision-making authority over the litigation. Under the terms of the Indemnification Agreement, PBM now controls the litigation, with Liquidia PAH’s primarily responsibility being to cooperate to support the litigation proceedings as needed. The Indemnification Agreement provides that Liquidia PAH and its affiliates will not be entitled to any proceeds resulting from, or bear any financial or other liability for, the United Therapeutics and Smiths Medical ASC litigation unless there is an event of default by PBM. Any Liquidia PAH litigation expenses not reimbursed by Henderson under the Financing Agreement will be reimbursed by PBM. Any proceeds received which Henderson is not entitled to under the Financing Agreement will be due to PBM. As of the Closing Date of the Merger Transaction, Liquidia PAH recorded an Indemnification Asset of $1,065,538. The Indemnification Asset is increased as the Company records third party legal and litigation expenses related to the United Therapeutics and Smiths Medical ASC litigation. As of March 31, 2021 and December 31, 2020, the Indemnification Asset and Litigation Finance Payable were classified as long-term assets and liabilities, respectively as it is considered unlikely that the litigation would conclude prior to March 31, 2022.

Stockholders' Equity Authorized

Stockholders' Equity Authorized Capital	3 Months Ended
	Mar. 31, 2021
Stockholders' Equity Authorized Capital
Stockholders' Equity Authorized Capital	4. Stockholders’ Equity Authorized Capital As of March 31, 2021, the authorized capital of the Company consists of 90,000,000 shares of capital stock, $0.001 par value per share, of which 80,000,000 shares are designated as common stock and 10,000,000 shares are designated as preferred stock. Common Stock Upon any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company, the holders of the common stock shall be entitled to receive that portion of the remaining funds to be distributed to the stockholders, subject to the liquidation preferences of any outstanding preferred stock, if any. Such funds shall be paid to the holders of common stock on the basis of the number of shares so held by each of them. Issuance of Common Stock on April 13, 2021 from a Private Placement On April 12, 2021, the Company entered into a Common Stock Purchase Agreement (the “Purchase Agreement”) with a fund and account managed by Caligan Partners LP and certain other accredited investors for the sale by the Company in a private placement (the “Private Placement”) of an aggregate of 8,626,037 shares of the Company’s Common Stock at a purchase price of $2.52 per share. The Private Placement closed on April 13, 2021 and the Company received gross proceeds of approximately $21.7 million. The Company intends to use the proceeds from the Private Placement to strengthen its commercial capability for the introduction of LIQ861 and the subcutaneous administration of Treprostinil Injection, for growth initiatives, and for general corporate purposes. Issuance of Common Stock on July 2, 2020 from an Underwritten Public Offering On June 29, 2020, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with Jefferies LLC, as representative of the several underwriters named therein (collectively, the “Underwriters”), pursuant to which 9,375,000 shares of the Company’s Common Stock were sold in an underwritten registered public offering at an offering price of $8.00 per Share (the “Offering”). The Offering closed on July 2, 2020, and the Company received net proceeds of approximately $70.3 million from the sale of the Shares, after deducting the underwriting discounts and commissions and other offering expenses. The Company intends to use the net proceeds from this Offering for ongoing commercial development of LIQ861 and for general corporate purposes. The Company’s management will retain broad discretion over the allocation of the net proceeds. Issuance of Common Stock from the ATM Agreement Commencing in August 2019 The Company entered into a sales agreement (the “ATM Agreement”) with Jefferies LLC (“Jefferies”) to issue and sell shares of the Company’s common stock, having an aggregate offering price of up to $40.0 million, from time to time during the term of the ATM Agreement, through an “at-the-market” equity offering program at the Company’s sole discretion, under which Jefferies will act as the Company’s agent and/or principal. The Company pays Jefferies a commission equal to 3.0% of the gross proceeds of any common stock sold through Jefferies under the ATM Agreement. During the three months ended March 31, 2020, Liquidia Technologies sold 131,425 shares of common stock for net proceeds of $0.7 million after deducting the underwriting discounts and other offering expenses under the ATM Agreement. Warrants During the three months ended March 31, 2021 and 2020, no warrants to purchase shares of common stock were exercised. ​ As of March 31, 2021 outstanding warrants consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ ​ ​ ​ ​ ​ warrants Exercise Price Expiration Date SVB Warrant ​ 100,000 ​ $ 3.05 ​ February 26, 2031 Other warrants ​ 106,274 ​ $ 0.02 ​ December 31, 2026 ​ As of December 31, 2020 outstanding warrants consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ ​ ​ ​ ​ ​ warrants Exercise Price Expiration Date Other warrants ​ 106,274 ​ $ 0.02 ​ December 31, 2026 ​

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2021
Stock-Based Compensation
Stock-Based Compensation	5. Stock-Based Compensation The Company’s 2020 Long-Term Incentive Plan (the “2020 Plan”) was approved by stockholders in November 2020. In addition to stock options, the 2020 Plan provides for the granting of stock appreciation rights, stock awards, stock units, and other stock-based awards. The 2020 Plan provides for accelerated vesting under certain change of control transactions. A total of 1,700,000 shares of the Company’s common stock was initially authorized and reserved for issuance under the 2020 Plan. This reserve will automatically increase each subsequent anniversary of January 1 through 2030, by an amount equal to the smaller of (a) 4% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, or (b) an amount determined by the Board of Directors (the “Evergreen Provision”). On January 1, 2021, the number of shares of common stock available for issuance under the 2020 Plan automatically increased by 1,733,432 shares to 2,955,432 shares from 1,222,000 pursuant to the Evergreen Provision. As of March 31, 2021, the Company had 1,582,139 shares available to issue under the 2020 Plan. The 2020 Plan replaced the Company’s 2018 Long-Term Incentive Plan (the “2018 Plan”) and as a result the 2018 Plan was discontinued. The 2018 Plan had replaced the 2016 Equity Incentive Plan (the “2016 Plan”) and 2004 Stock Option Plan (the “2004 Plan”) as the Company’s primary long-term incentive program. The 2018, 2016 and 2004 Plans have been discontinued but the outstanding awards under the 2018, 2016 and 2004 Plans will continue to remain in effect in accordance with their terms. Shares that are returned under the 2018, 2016 and 2004 Plans upon cancellation, termination or otherwise of awards outstanding under the 2018, 2016 and 2004 Plans will not be available for grant under the 2020 Plan. As of March 31, 2021, the Company had reserved for issuance During December 2020, the Company issued a stock option grant to its new chief executive officer (the “CEO”) to purchase up to 2,000,000 shares of the Company’s common stock (the “CEO Option”) at the exercise price on the grant date of $3.00 per share. The CEO Option was issued outside of the 2020 Plan and is subject to the following vesting schedule; 25% of the CEO Option will become vested and exercisable on the first anniversary of December 14, 2020 and the balance will become vested and exercisable in equal monthly installments over the following thirty-six months , subject to the CEO’s continuous employment with the Company. However, the CEO Option is subject to the following accelerated vesting: (i) if the Company receives tentative approval by the FDA of the Company’s New Drug Application for LIQ861 prior to June 30, 2022, and the CEO is actively employed by the Company on such date, then 25% of the then-unvested portion of the CEO Option shall become vested and exercisable as of the date of the FDA’s approval; and (ii) if the Company achieves commercial availability of the subcutaneous Treprostinil product with cartridge supplies sufficient to support the market for one year by December 31, 2021, and the CEO is actively employed by the Company on such date, then 25% of the then-unvested portion of the CEO Option shall become vested and exercisable as of the date the Company can document by competent proof to the Board of the achievement of such milestone. In addition, the CEO Option will become 100 % vested upon certain change of control transactions. As of March 31, 2021, these milestones had not been achieved. Stock-Based Compensation Valuation and Expense The Company accounts for its employee stock-based compensation plans using the fair value method. The fair value method requires the Company to estimate the grant-date fair value of its stock-based awards and amortize this fair value to compensation expense over the requisite service period or vesting term. The fair value of each option grant is estimated using a Black-Scholes option-pricing model. For restricted stock units (“RSUs”), the grant-date fair value is based upon the market price of the Company’s common stock on the date of the grant. This fair value is then amortized to compensation expense over the requisite service period or vesting term. The Company recorded the following stock-based compensation expense: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ By Expense Category: 2021 2020 ​ Research and development ​ $ 251,000 ​ $ 275,141 ​ General and administrative ​ 494,000 ​ 603,822 ​ Total stock-based compensation expense ​ $ 745,000 ​ $ 878,963 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ By Type of Award: 2021 2020 ​ Stock options ​ $ 762,000 ​ $ 854,770 ​ Restricted stock units ​ (17,000) ​ 24,193 ​ Total stock-based compensation expense ​ $ 745,000 ​ $ 878,963 ​ ​ The following table summarizes the unamortized compensation expense and the remaining years over which such expense would be expected to be recognized, on a weighted average basis, by type of award: ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2021 ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Remaining ​ ​ ​ ​ ​ Recognition ​ Unamortized Period ​ ​ Expense ​ (Years) Stock options ​ $ 9,859,000 3.4 Restricted stock units ​ $ 865,000 ​ 1.8 ​ Stock Options The following table summarizes the assumptions used for estimating the fair value of stock options granted under the Black-Scholes option-pricing model during: ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ 2021 2020 Expected dividend yield ​ — ​ — Risk-free interest rate 0.62% - 1.67% 0.90% - 1.60% Expected volatility 93% - 94% 87% - 90% Expected life (years) 5.2 - 6.1 6.1 ​ As a result of using these assumptions in the Black-Scholes option-pricing model, the weighted average fair value for options granted during the three months ended March 31, 2021 and 2020 was $2.09 and $2.38 per share, respectively. The following describes each of these assumptions and the Company’s methodology for determining each assumption: Expected Dividend Yield The dividend yield percentage is zero because the Company neither currently pays dividends nor intends to do so during the expected option term. Risk-Free Interest Rate The risk-free interest rate is based on the U.S. Treasury yield curve approximating the term of the expected life of the award in effect on the date of grant. Expected Volatility Expected stock price volatility is based on a weighted average of several peer public companies and the historical volatility of the Company’s common stock during the period for which it has traded since the initial public offering. For purposes of identifying peer companies, the Company considered characteristics such as industry, length of trading history and similar vesting terms. Expected Life The expected life represents the period the awards are expected to be outstanding. The Company’s historical share option exercise experience does not provide a reasonable basis upon which to estimate an expected term because of a lack of sufficient data. Therefore, the Company estimates the expected term by using the simplified method. The following table summarizes the Company’s stock option activity during the three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ ​ ​ ​ ​ ​ Average ​ Contractual ​ Aggregate ​ ​ Number of ​ Exercise ​ Term ​ Intrinsic ​ ​ Shares ​ Price ​ (in years) ​ Value Outstanding as of December 31, 2020 4,692,071 ​ $ 5.51 ​ Granted 1,162,918 ​ $ 2.80 ​ Exercised (623) ​ $ 2.33 ​ Cancelled (811,578) ​ $ 7.46 ​ Outstanding as of March 31, 2021 5,042,788 ​ $ 4.57 8.4 ​ $ 98,081 Exercisable as of March 31, 2021 1,042,063 ​ $ 8.21 3.9 ​ $ 11,020 Vested and expected to vest as of March 31, 2021 4,998,291 ​ $ 4.55 8.4 ​ $ 98,081 ​ The aggregate intrinsic value of stock options in the table above represents the difference between the $2.69 closing price of the Company’s common stock as of March 31, 2021 and the exercise price of outstanding, exercisable, and vested and expected to vest in-the-money stock options. Restricted Stock Units Restricted Stock Units (“RSUs”) represent the right to receive shares of common stock of the Company at the end of a specified time period or upon the achievement of a specific milestone. RSUs can only be settled in shares of the Company’s common stock. During the three months ended March 31, 2021, the Board of Directors approved grants of an aggregate of performance-based RSUs to employees. These performance RSUs vest upon the tentative approval by the FDA of the Company’s New Drug Application for LIQ861. The achievement of this performance milestone was not deemed probable as of March 31, 2021. During the three months ended March 31, 2020, the Board of Directors approved grants of an aggregate of four A summary of nonvested RSU awards outstanding as of March 31, 2021 and changes during the three months then ended is as follows: ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date ​ ​ Number of ​ Fair Value ​ ​ RSUs ​ (per RSU) Nonvested as of December 31, 2020 88,131 ​ $ 4.68 Granted 334,015 ​ 2.97 Vested (10,366) ​ 3.31 Forfeited (52,403) ​ 5.59 Nonvested as of March 31, 2021 359,377 ​ $ 3.00 ​ Employee Stock Purchase Plan In November 2020, stockholders approved the Liquidia Corporation 2020 Employee Stock Purchase Plan (the “2020 ESPP”). As of March 31, 2021, a total of 300,000 shares of the Company’s common stock are reserved for issuance under the 2020 ESPP. Subject to any plan limitations, the 2020 ESPP allows eligible employees to contribute through payroll deductions up to $25,000 per year of their earnings for the purchase of the Company’s common stock at a discounted price per share. The initial three-month offering period is expected to commence on or about June 1, 2021 followed by successive six-month offering periods thereafter beginning March and September. Unless otherwise determined by the administrator, the Company’s common stock will be purchased for the accounts of employees participating in the 2020 ESPP at a price per share that is 85% of the fair market value of the Company’s common stock on the last trading day of the offering period. ​

License Agreements

License Agreements	3 Months Ended
	Mar. 31, 2021
License Agreements
License Agreements	6. License Agreements The Company performs research under a license agreement with The University of North Carolina at Chapel Hill (“UNC”) as amended to date (the “UNC License Agreement”). As part of the UNC License Agreement, the Company holds an exclusive license to certain research and development technologies and processes in various stages of patent pursuit, for use in its research and development and commercial activities, with a term until the expiration date of the last to expire patent subject to the UNC License Agreement, subject to industry standard contractual compliance. Under the UNC License Agreement, the Company is obligated to pay UNC royalties equal to a low single digit percentage of all net sales of drug products whose manufacture, use or sale includes any use of the technology or patent rights covered by the UNC License Agreement. The Company may grant sublicenses of UNC licensed intellectual property in return for specified payments based on a percentage of any fee, royalty or other consideration received. ​

Revenue From Contracts With Cus

Revenue From Contracts With Customers	3 Months Ended
	Mar. 31, 2021
Revenue From Contracts With Customers
Revenue From Contracts With Customers	7. Revenue From Contracts With Customers On August 1, 2018, the Company partnered with Sandoz in the Promotion Agreement to launch the first-to-file generic of Treprostinil Injection for the treatment of patients with PAH. Under the Promotion Agreement, the Company provides certain promotional and nonpromotional activities on an exclusive basis for the product in the United States of America for the treatment of PAH. In addition, the Company paid Sandoz $20 million at the inception of the Promotion Agreement, in consideration for the right to conduct the promotional and nonpromotional activities for the product. In exchange for its services, the Company is entitled to receive a portion of net profits, as defined within the Promotion Agreement, based on specified profit levels associated with the product. The Company determined that certain activities within the contract are within the scope of ASC 808, Collaborative Arrangements. The commercialization of the product is a joint operating activity where the Company will provide promotional and nonpromotional activities for Sandoz’s product and Sandoz will be responsible for items such as supply of the product, distribution to customers, managing sales, processing returns, and regulatory matters. Both parties will be active participants, each carrying out its assigned responsibilities, and participating in the joint operating activity and will share in the risks and rewards of the commercialization through the profit-sharing arrangement. In addition, the Company determined that the services provided under the Promotion Agreement fall within the scope of Topic 606. The promotional and nonpromotional activities the Company performs are one of the services the Company expects to provide as part of its ordinary activities, and it is receiving consideration for this service from Sandoz in the form of a share of “Net Profits” (as defined in the Promotion Agreement). The Company has one combined performance obligation under the Promotion Agreement, which is to perform promotional and nonpromotional activities to encourage the appropriate use of the product in accordance with the product labeling and applicable law. As such, and in accordance with ASU 2018-18: Clarifying the Interaction between Topic 808 and Topic 606, the Company will account for the entire Promotion Agreement under Topic 606. The Company derived its revenue during the three months ended March 31, 2021 from the Promotion Agreement. The Company had

Property, Plant and Equipment

Property, Plant and Equipment	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment
Property, Plant and Equipment	8. Property, Plant and Equipment Property, plant and equipment consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2021 ​ 2020 Lab and build-to-suit equipment ​ $ 7,478,278 ​ $ 7,499,645 Office equipment ​ 31,205 ​ 31,205 Furniture and fixtures ​ 257,774 ​ 257,774 Computer equipment ​ 404,558 ​ 404,558 Leasehold improvements ​ 11,524,738 ​ 11,524,738 Construction-in-progress ​ 100,820 ​ 65,820 Total property, plant and equipment ​ 19,797,373 ​ 19,783,740 Accumulated depreciation and amortization ​ (13,501,305) ​ (12,978,170) Property, plant and equipment, net ​ $ 6,296,068 ​ $ 6,805,570 ​ The Company recorded depreciation and amortization expense of $523,135 and $732,029 for the three months ended March 31, 2021 and 2020, respectively. ​

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2021
Income Taxes
Income Taxes	9. Income Taxes The Company did not record a federal or state income tax expense or benefit for the three months ended March 31, 2021 and 2020 as a result of the establishment of a full valuation allowance being required against the Company’s net deferred tax assets. ​

Leases, Commitments and Conting

Leases, Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Leases, Commitments and Contingencies
Leases, Commitments and Contingencies	10. Leases, Commitments and Contingencies Commitments Leases The Company leases certain laboratory space, office space, and equipment. Leases with an initial term of 12 months or less are not recorded on the balance sheet; the Company recognizes lease expense for these leases on a straight-line basis over the lease term. For lease agreements entered into or reassessed after the adoption of Topic 842, the Company combines lease and non-lease components, if any. Most leases include one or more options to renew. The exercise of lease renewal options is at the Company’s sole discretion. Certain leases also include options to purchase the leased property. Consistent with past practice and current intent, the Company has recognized all such purchase options as part of its right-of-use assets and lease liabilities. The depreciable life of assets and leasehold improvements are limited by the expected lease term unless there is a transfer of title or purchase option reasonably certain of exercise. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. The Company conducts its operations from leased facilities of approximately 45,000 square feet in Morrisville, North Carolina with a lease expiration date of October 31, 2026. In addition, the Company leases specialized laboratory equipment under finance leases. The related right-of-use assets are amortized on a straight-line basis over the lesser of the lease term or the estimated useful life of the asset. The Company does not have access to certain inputs used by its lessors to calculate the rate implicit in its finance leases. As such, the Company utilized its estimated incremental borrowing rate for the discount rate applied to its finance leases. The original incremental borrowing rate used on finance leases was 7.5% . During February 2021, the Company exercised the lease purchase option for certain finance leases that had expired and entered into a lease modification agreement with its existing lessor for certain other finance leases. The modification resulted in an increase in the remaining lease term of between 24 and 48 months as well as a decrease in the monthly payments associated with the respective modified leases. The incremental borrowing rate used on the modified leases was 6.5% . The lease modification had an immaterial impact on the Company’s condensed consolidated financial statements. The Company’s lease cost is reflected in the accompanying condensed statements of operations and comprehensive loss as follows ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ Classification 2021 2020 Operating lease cost General and administrative ​ $ 195,118 ​ $ 195,118 Finance lease cost: ​ ​ Amortization of lease assets General and administrative ​ 143,451 ​ 348,951 Interest on lease liabilities Interest expense ​ 4,972 ​ 38,903 Total Lease Cost ​ ​ ​ $ 343,541 ​ $ 582,972 ​ The weighted average remaining lease term and discount rates as of March 31, 2021 were as follows: ​ ​ ​ ​ Weighted average remaining lease term (years): ​ Operating leases 5.6 ​ Finance leases 3.0 ​ Weighted average discount rate: ​ Operating leases 10.3 % Finance leases 6.6 % ​ The discount rate for operating leases was estimated based upon market rates of collateralized loan obligations of comparable companies on comparable terms. The future minimum lease payment as of March 31, 2021 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ Year ending December 31: ​ Leases ​ Leases ​ Total 2021 - nine months remaining ​ $ 907,284 ​ $ 289,774 ​ $ 1,197,058 2022 ​ 1,243,934 ​ 342,315 ​ 1,586,249 2023 ​ 1,283,253 ​ 195,180 ​ 1,478,433 2024 ​ 1,316,540 ​ 114,612 ​ 1,431,152 2025 ​ 1,355,923 ​ 64,142 ​ 1,420,065 Thereafter ​ 1,157,807 ​ — ​ 1,157,807 Total minimum lease payments ​ 7,264,741 ​ 1,006,023 ​ 8,270,764 Less: Interest ​ (1,752,099) ​ (92,112) ​ (1,844,211) Present value of lease liabilities ​ $ 5,512,642 ​ $ 913,911 ​ $ 6,426,553 ​ Commitments I n connection with the Merger Transaction, we agreed to issue additional consideration of up to 2,708,333 additional shares of common stock to the former equity holders of RareGen (now Liquidia PAH) contingent on achievement of certain Liquidia PAH revenue targets during the year ending December 31, 2021 . As of March 31, 2021 and December 31, 2020, the fair value of this contingent consideration was deemed to be immaterial. In March 2012, the Company entered into an agreement, as amended, with Chasm Technologies, Inc. for manufacturing consulting services related to the Company’s manufacturing capabilities during the term of the agreement. The Company agreed to pay future contingent royalties, totaling no more than $1,500,000, on net sales of certain products. As of March 31, 2021, none of the contingent royalties had been earned. We enter into contracts in the normal course of business with contract service providers to assist in the performance of our research and development and manufacturing activities. Subject to required notice periods and our obligations under binding purchase orders, we can elect to discontinue the work under these agreements at any time. In addition, we have entered into a multi-year agreement with LGM Pharma, LLC (LGM) to produce active pharmaceutical ingredients for LIQ861 . . . We also have employment agreements with certain employees which require the funding of a specific level of payments, if certain events, such as a change in control or termination without cause, occur. Contingencies The Company from time-to-time is subject to claims and litigation in the normal course of business, none of which the Company believes represent a risk of material loss or exposure. ​

Long-term Debt

Long-term Debt	3 Months Ended
	Mar. 31, 2021
Long-term Debt
Long-term Debt	11. Long-Term Debt Long-term debt consisted of the following as of March 31, 2021 and December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ Maturity Date ​ 2021 ​ 2020 Pacific Western Bank term loan ​ October 25, 2022 ​ $ — ​ $ 10,292,485 Silicon Valley Bank term loan ​ September 1, 2024 ​ ​ 10,176,481 ​ ​ — Long-term debt ​ ​ ​ $ 10,176,481 ​ $ 10,292,485 ​ During 2020, the Company, Liquidia Merger Sub and RareGen Merger Sub entered into a Joinder and Second Amendment to Amended and Restated Loan and Security Agreement, dated as of October 26, 2018 (the “A&R LSA”), with Pacific Western Bank (“PWB”). The A&R LSA included interest only payments through December 2019 with principal and interest payments beginning in January 2020 and was scheduled to mature in October 2022. On February 26, 2021 (the “Effective Date”), the Company and its two wholly owned subsidiaries, Liquidia Technologies and Liquidia PAH, entered into a Loan and Security Agreement (the “Loan Agreement”) with SVB. The Loan Agreement established a term loan facility in the aggregate principal amount of up to $20.5 million (the “Term Loan Facility”). An initial $10.5 million (the “Term A Loan”) was funded on March 1, 2021 and was used to satisfy the Company’s existing obligations under the A&R LSA, consisting of approximately $9.4 million in outstanding principal and interest, and such obligations are considered fully repaid and terminated as of that date, with the excess proceeds funded to the Company. The Company accounted for the repayment of the A&R LSA in accordance with ASC 405, Extinguishments of Liabilities Availability of $5.0 million under a second tranche of the Term Loan Facility (the “Term B Loan”) is conditioned upon Liquidia having received tentative FDA approval for LIQ861 by June 30, 2022, and availability of $5.0 million under a third tranche of the Term Loan Facility (the “Term C Loan” and, collectively with the Term A Loan and Term B Loan, the “Term Loans”) is conditioned upon Liquidia having received final and unconditional FDA approval for LIQ861 by December 31, 2022. As security for its obligations under the Loan Agreement, Liquidia granted SVB a continuing security interest in substantially all of the assets of Liquidia, other than intellectual property. The Term Loans made under the Term Loan Facility mature on September 1, 2024 (the “Maturity Date”) and have an interest-only monthly payment period through March 31, 2023 (the “Interest-Only Period”). Following the Interest-Only Period, the Company will begin making monthly payments of principal and interest until the Maturity Date. Interest will accrue on the unpaid principal balance of the outstanding Term Loans at a floating per annum rate equal to the greater of (i) the Wall Street Journal prime rate plus 0.75% and (ii) four percent (4.0%). Furthermore, on the earliest to occur of (x) the Maturity Date, (y) the date the Term Loans are repaid in full or (z) the date of termination of the Loan Agreement, the Company shall pay to SVB five percent (5.0%) of the aggregate original principal amount of all Term Loans made by SVB (the “Final Payment”). In the event that Liquidia elects to terminate the Term Loan Facility in its entirety, it may do so at any time by paying the outstanding principal balance, unpaid accrued interest, the Final Payment and a prepayment fee equal to (i) five percent (5.0%) of the outstanding principal balance, if such prepayment is made during the Interest-Only Period or (ii) zero, if such prepayment is made after the Interest-Only Period and before the Maturity Date. Subject to certain exceptions, the Loan Agreement contains covenants prohibiting the Company from, among other things, and subject to certain limited exceptions: (a) conveying, selling, leasing, transferring or otherwise disposing of its properties or assets; (b) liquidating or dissolving; (c) engaging in any business other than the business currently engaged in or reasonably related thereto by it or any of its subsidiaries; (d) engaging in mergers or acquisitions; (e) incurrence of additional indebtedness; (f) allowing any lien or encumbrance on any of its property; (g) paying any dividends; (h) repurchasing its equity; and (i) making payment on subordinated debt. In addition, the Loan Agreement requires Liquidia to maintain an unrestricted and unencumbered “Minimum Cash Balance” (as defined therein) equal to at least (i) $30.0 million during the period commencing on the Effective Date and including the date immediately prior to the funding date of the Term B Loan (the “Term B Loan Funding Date”) and (ii) during the period commencing on the Term B Loan Funding Date through and including the date immediately prior to the funding date of the Term C Loan (the “Term C Loan Funding Date”), $35.0 million. Moreover, in the event the Minimum Cash Balance is not achieved during any calendar quarter during the term of the Loan Agreement, the Loan Agreement requires Liquidia to maintain cumulative “Cash Burn” (as defined in the Loan Agreement) for the periods ending March 31, 2021, June 30, 2021, September 30, 2021, December 31, 2021, March 31, 2022 and June 30, 2022 and for each calendar quarter thereafter equal to $10.5 million, $17.0 million, $23.0 million, $28.5 million, $33.5 million and $38.0 million, respectively; provided however provided further , that upon the Term C Loan Funding Date, the Cash Burn covenant shall no longer apply. The Company was in compliance with the loan covenants as of March 31, 2021. The Loan Agreement also contains customary events of default, including among other things, the Company’s failure to make any principal or interest payments when due, the occurrence of certain bankruptcy or insolvency events or the Company’s breach of the covenants under the Loan Agreement, or other material adverse changes relating to Liquidia. Furthermore, per the Loan Agreement, an event of default shall occur upon any formal court ruling against Liquidia that the SVB determines in its good faith business judgment is reasonably likely to prohibit its ability to obtain final approval from the FDA with respect to its New Drug Application for LIQ861 or impair or delay Liquidia’s ability to commercialize LIQ861 as currently contemplated. Upon the occurrence of an event of default, SVB may, among other things, accelerate Liquidia’s obligations under the Loan Agreement. In connection with the Loan Agreement, the Company issued to SVB a warrant, dated as of the Effective Date (the “SVB Warrant”) to purchase up to 200,000 shares of the Company’s common stock, $0.001 par value per share (the “Common Stock”), of which (x) 100,000 shares vested on the Effective Date, with an exercise price per share equal to $3.05, and (y) 50,000 shares shall become exercisable on each of the Term B Loan Funding Date and Term C Loan price of the Common Stock on the applicable funding date and (ii) the closing price per share of Common Stock on the trading day prior to applicable funding date. The SVB Warrant is exercisable for ten (10) years from the date of issuance, and will be exercised automatically on a net issuance basis if not exercised prior to the expiration date and if the then-current fair market value of one share of Common Stock is greater than the exercise price then in effect. The Company evaluated the features of the Loan Agreement and SVB Warrant in accordance with ASC 480, Distinguishing Liabilities from Equity , Derivatives and Hedging . The Company determined that the Loan Agreement and Warrant did not contain any features that would qualify as a derivative or embedded derivative. In addition, the Company determined that the SVB Warrant should be classified as equity. The value of the SVB Warrant is included in Additional Paid-in-Capital in the Company’s condensed consolidated balance sheet as of March 31, 2021. The estimated fair value of the SVB Warrant of was calculated using the Black-Scholes Option Pricing Model based on the following inputs: ​ ​ ​ ​ Expected dividend yield ​ — Risk-free interest rate 1.43% Expected volatility 90.8% Expected life (years) 10.0 ​ In accordance with ASC 470, Debt allocated to the Term A Loan. In addition, the Company incurred fees of approximately , which were recorded as a reduction in the face value of the Term A Loan. The debt discount and debt issuance costs are being amortized to interest expense and the Final Payment is being accreted using the effective interest method over the term of the Term A Loan. Scheduled annual maturities of long-term debt as of March 31, 2021 are as follows: ​ ​ ​ ​ ​ Year ending December 31: ​ 2021 – nine months remaining ​ $ — 2022 ​ — 2023 ​ 5,250,000 2024 ​ ​ 5,250,000 Thereafter ​ — Total ​ 10,500,000 Less: Unamortized discount, debt issuance costs and accretion ​ (323,519) Less: Current portion of long-term debt ​ — Long-term debt, noncurrent ​ $ 10,176,481 ​

Significant Accounting Policies

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Basis of Presentation and Summary of Significant Accounting Policies
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation The unaudited interim condensed consolidated financial statements as of March 31, 2021 and for the three months ended March 31, 2021 and 2020 have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial reporting. These condensed consolidated financial statements are unaudited and, in the opinion of management, include all adjustments (consisting only of normal recurring adjustments and accruals) necessary for a fair statement of the results for the periods presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The year-end condensed consolidated balance sheet data was derived from the Company’s audited consolidated financial statements but does not include all disclosures required by GAAP. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2021. Certain information and footnote disclosures normally included in the annual consolidated financial statements prepared in accordance with GAAP have been omitted in accordance with the SEC’s rules and regulations for interim reporting. The Company’s financial position, results of operations and cash flows are presented in U.S. Dollars. The accompanying unaudited condensed consolidated financial statements and related notes should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2020, which are included in the Company’s 2020 Annual Report on Form 10-K. There have been no material changes to the Company’s significant accounting policies during the three months ended March 31, 2021 compared with the significant accounting policies disclosed in Note 2 of the consolidated financial statements for the years ended December 31, 2020 and 2019, which are included in the Company’s 2020 Annual Report on Form 10-K.
Consolidation, Policy [Policy Text Block]	Consolidation The accompanying condensed consolidated financial statements include the Company’s wholly owned subsidiaries, Liquidia Technologies and Liquidia PAH. All intercompany accounts and transactions have been eliminated.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities, at the date of the financial statements, as well as the reported amounts of revenues and expenses during the period. These estimates are based on historical experience and various other assumptions believed reasonable under the circumstances. The Company evaluates its estimates on an ongoing basis and makes changes to the estimates and related disclosures as experience develops or new information becomes known. Actual results will most likely differ from those estimates.
Reclassification, Comparability Adjustment [Policy Text Block]	Revision of Previously Issued Financial Statements During the three months ended June 30, 2020, the Company identified an error in the matter in which it calculated diluted weighted common shares outstanding and diluted net loss per common share. While the Company has included common stock warrants whose exercise price is de minimis in the calculation of basic weighted average common shares outstanding and basic net loss per common share, these warrants were inappropriately excluded from the calculation of diluted weighted average common shares outstanding and diluted net loss per common share, which resulted in an error in diluted weighted average common shares outstanding for the three month period ended March 31, 2020. The Company has evaluated this error and determined that this presentation error was not material to any prior annual or interim periods. However, the Company is revising the previously presented March 31, 2020 diluted weighted common shares outstanding as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, 2020 ​ As Presented As Revised Diluted weighted average shares outstanding ​ 28,322,342 ​ 28,428,616
Concentration Risk, Credit Risk, Policy [Policy Text Block]	Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents as of March 31, 2021 were $53.6 million and included cash investments in money market funds of $42.7 million. Cash as of December 31, 2020 was $65.3 million and included no cash equivalents. Accounts Receivable Accounts receivable are stated at net realizable value including an allowance for doubtful accounts as of each balance sheet date, if applicable. As of March 31, 2021 and December 31, 2020, the Company has not recorded an allowance for doubtful accounts. Business Combination In a business combination, the acquisition method of accounting requires that the assets acquired and liabilities assumed be recorded as of the date of the acquisition at their respective fair values with limited exceptions. Assets acquired and liabilities assumed in a business combination that arise from contingencies are generally recognized at fair value. If fair value cannot be determined, the asset or liability is recognized if probable and reasonably estimable; if these criteria are not met, no asset or liability is recognized. Transaction costs and costs to restructure the acquired company are expensed as incurred. The operating results of the acquired business are reflected in the Company’s consolidated financial statements after the date of the acquisition. Long-Lived Assets The Company reviews long-lived assets, including definite-life intangible assets, for realizability on an ongoing basis. Changes in depreciation and amortization, generally accelerated depreciation and variable amortization, are determined and recorded when estimates of the remaining useful lives or residual values of long-term assets change. The Company also reviews for impairment when conditions exist that indicate the carrying amount of the assets may not be fully recoverable. In those circumstances, the Company performs undiscounted operating cash flow analyses to determine if an impairment exists. When testing for asset impairment, the Company groups assets and liabilities at the lowest level for which cash flows are separately identifiable. Any impairment loss is calculated as the excess of the asset’s carrying value over its estimated fair value. Fair value is estimated based on the discounted cash flows for the asset group over the remaining useful life or based on the expected cash proceeds for the asset less costs of disposal. Any impairment losses would be recorded in the consolidated statements of operations. To date, no such impairments have occurred. Goodwill The Company acquired goodwill on its condensed consolidated balance sheet during the fourth quarter of 2020 from the Merger Transaction. The Company assesses goodwill for impairment at least annually as of July 1 or whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. The Company has one reporting unit. The Company has the option to first assess qualitative factors to determine whether events or circumstances indicate it is more likely than not that the fair value of a reporting unit is greater than its carrying amount, in which case a quantitative impairment test is not required. Per ASU 2017-04 the quantitative goodwill impairment test is performed by comparing the fair value of the reporting unit with its carrying amount, including goodwill. If the fair value of the reporting unit exceeds its carrying amount, goodwill is not impaired. An impairment loss is recognized for any excess of the carrying amount of the reporting unit’s goodwill over the fair value up to the amount of goodwill allocated to the reporting unit. Income tax effects from any tax-deductible goodwill on the carrying amount of the reporting unit are considered when measuring the goodwill impairment loss, if applicable. To date, no such impairments have occurred. Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash and cash equivalents. The Company is exposed to credit risk, subject to federal deposit insurance, in the event of default by the financial institutions holding its cash and cash equivalents to the extent of amounts recorded on the condensed consolidated balance sheet. 81.5% of the Company’s cash and cash equivalents are held with Silicon Valley Bank (“SVB”). As of and for the three months ended March 31, 2021, one customer accounted for all of the Company's accounts receivable and revenue.
Revenue from Contract with Customer [Policy Text Block]	Revenue Recognition The Company recognizes revenue in accordance with Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers (Topic 606). The core principle of Topic 606 is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. The following five steps are applied to achieve that core principle: ● Step 1: Identify the contract with the customer ● Step 2: Identify the performance obligations in the contract ● Step 3: Determine the transaction price ● Step 4: Allocate the transaction price to the performance obligations in the contract ● Step 5: Recognize revenue when the company satisfies a performance obligation In order to identify the performance obligations in a contract with a customer, the Company assesses the promised goods or services in the contract and identifies each promised good or service that is distinct. If a good or service is not distinct, the good or service is combined with other promised goods or services until a bundle of goods or services is identified that is distinct. The transaction price is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer. The consideration promised in a contract with a customer may include fixed amounts, variable amounts, or both. Variable consideration is included in the transaction price only to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. The Company evaluates any non-cash consideration, consideration payable to the customer, potential returns and refunds, and whether consideration contains a significant financing element in determining the transaction price. Revenue is measured based on consideration specified in a contract with a customer. The Company recognizes revenue when it satisfies a performance obligation by transferring control over a service to a customer. The amount of revenue recognized reflects estimates for refunds and returns, which are presented as a reduction of Accounts receivable where the right of setoff exists.
Share-based Payment Arrangement [Policy Text Block]	Stock-Based Compensation The Company estimates the grant date fair value of its stock-based awards and amortizes this fair value to compensation expense on a straight-line basis over the requisite service period, which is generally the vesting period of the respective award (see Note 5). The grant date fair value of stock options is determined using the Black-Scholes option-pricing model.
Earnings Per Share, Policy [Policy Text Block]	Net Loss Per Share Basic net loss per share is calculated by dividing net loss attributable to common stockholders by the weighted average shares outstanding during the period, without consideration of common stock equivalents. Diluted net loss per share is calculated by adjusting the weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. For purposes of the diluted net loss per share calculation, stock options, restricted stock units and the SVB Warrant (see Note 11) are considered to be common stock equivalents but are excluded from the calculation of diluted net loss per share because their effect would be anti-dilutive. Due to their anti-dilutive effect, the calculation of diluted net loss per share for the three months ended March 31, 2021 and 2020 does not include the following common stock equivalent shares: ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ ​ ​ 2021 ​ 2020 ​ Stock Options 4,776,022 2,119,523 ​ Restricted Stock Units 313,099 48,759 ​ SVB Warrant ​ 36,667 ​ — ​ Total 5,125,788 2,168,282 ​ ​ For the three months ended March 31, 2021 and 2020, certain common stock warrants are included in the calculation of basic and diluted net loss per share since their exercise price is de minimis.
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements In March 2020, the Financial Accounting Standards Board ("FASB") issued guidance that provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by the discontinuation of the London Interbank Offered Rate (“LIBOR”) or by another reference rate expected to be discontinued. The Company adopted this guidance during the first quarter of 2021 and it did not have a material impact on its consolidated financial position, results of operations or cash flows. In August 2020, the FASB issued ASU 2020-06, Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity
Fair Value of Financial Instruments, Policy [Policy Text Block]	Fair Value of Measurements The Company’s valuation of financial instruments is based on a three-tiered approach, which requires that fair value measurements be classified and disclosed in one of three tiers. The fair value hierarchy defines a three-level valuation hierarchy for disclosure of fair value measurements as follows: Level 1 — Quoted prices in active markets for identical assets or liabilities; Level 2 — Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly; and Level 3 — Unobservable inputs for the asset and liability used to measure fair value, to the extent that observable inputs are not available. The categorization of a financial instrument within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The following tables present the placement in the fair value hierarchy of financial liabilities measured at fair value as of March 31, 2021 and December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying March 31, 2021 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market mutual funds ​ $ 42,726,954 ​ $ — ​ $ — ​ $ 42,726,954 Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Silicon Valley Bank term loan ​ $ — ​ $ 10,072,320 ​ $ — ​ $ 10,176,481 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2020 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pacific Western Bank term loan ​ $ — ​ $ 9,842,069 ​ $ — ​ $ 10,292,485 ​ Money market mutual funds are included in cash and cash equivalents on the Company's condensed consolidated balance sheets. They are valued using quoted market prices and therefore are classified within Level 1 of the fair value hierarchy. The carrying amounts reflected in the Company's condensed consolidated balance sheets for cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued expenses and other liabilities approximate their fair values due to their short-term nature. The fair value of debt is measured in accordance with ASU 2016-01, Financial Instruments–Overall: Recognition and Measurement of Financial Assets and Financial Liabilities

Basis of Presentation and Sum_2

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2021
Notes Tables
Schedule of Error Corrections and Prior Period Adjustments [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, 2020 ​ As Presented As Revised Diluted weighted average shares outstanding ​ 28,322,342 ​ 28,428,616
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ ​ ​ 2021 ​ 2020 ​ Stock Options 4,776,022 2,119,523 ​ Restricted Stock Units 313,099 48,759 ​ SVB Warrant ​ 36,667 ​ — ​ Total 5,125,788 2,168,282 ​
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying March 31, 2021 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market mutual funds ​ $ 42,726,954 ​ $ — ​ $ — ​ $ 42,726,954 Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Silicon Valley Bank term loan ​ $ — ​ $ 10,072,320 ​ $ — ​ $ 10,176,481 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2020 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pacific Western Bank term loan ​ $ — ​ $ 9,842,069 ​ $ — ​ $ 10,292,485

Acquisition of RareGen LLC (n_2

Acquisition of RareGen LLC (now Liquidia PAH, LLC) (Tables)	3 Months Ended
	Mar. 31, 2021
Acquisition of RareGen LLC (now Liquidia PAH, LLC)
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	​ ​ ​ ​ ​ Number of common shares to be issued to RareGen’s members ​ 6,166,666 Multiplied by the fair value per share of Liquidia Technologies common stock ​ $ 3.38 Total estimated purchase price ​ $ 20,843,331
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	​ ​ ​ ​ ​ Cash $ 1,000,000 Property and equipment ​ 79,330 Prepaid and other current assets ​ 30,190 Intangible asset ​ 5,620,000 Contract acquisition costs ​ 12,980,000 Indemnification asset, related party ​ 1,065,538 Goodwill ​ 3,903,282 Less other current liabilities ​ (492,499) Less refund liability ​ (2,696,000) Less litigation finance payable, long-term ​ (646,510) Total estimated purchase price ​ $ 20,843,331

Stockholders' Equity Authoriz_2

Stockholders' Equity Authorized Capital (Tables)	3 Months Ended
	Mar. 31, 2021
Stockholders' Equity Authorized Capital
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]	As of March 31, 2021 outstanding warrants consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ ​ ​ ​ ​ ​ warrants Exercise Price Expiration Date SVB Warrant ​ 100,000 ​ $ 3.05 ​ February 26, 2031 Other warrants ​ 106,274 ​ $ 0.02 ​ December 31, 2026 ​ As of December 31, 2020 outstanding warrants consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ ​ ​ ​ ​ ​ warrants Exercise Price Expiration Date Other warrants ​ 106,274 ​ $ 0.02 ​ December 31, 2026

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2021
Stock-Based Compensation
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ By Expense Category: 2021 2020 ​ Research and development ​ $ 251,000 ​ $ 275,141 ​ General and administrative ​ 494,000 ​ 603,822 ​ Total stock-based compensation expense ​ $ 745,000 ​ $ 878,963 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ By Type of Award: 2021 2020 ​ Stock options ​ $ 762,000 ​ $ 854,770 ​ Restricted stock units ​ (17,000) ​ 24,193 ​ Total stock-based compensation expense ​ $ 745,000 ​ $ 878,963 ​
Share-based Payment Arrangement, Nonvested Award, Cost [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2021 ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Remaining ​ ​ ​ ​ ​ Recognition ​ Unamortized Period ​ ​ Expense ​ (Years) Stock options ​ $ 9,859,000 3.4 Restricted stock units ​ $ 865,000 ​ 1.8
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ 2021 2020 Expected dividend yield ​ — ​ — Risk-free interest rate 0.62% - 1.67% 0.90% - 1.60% Expected volatility 93% - 94% 87% - 90% Expected life (years) 5.2 - 6.1 6.1
Share-based Payment Arrangement, Option, Activity [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ ​ ​ ​ ​ ​ Average ​ Contractual ​ Aggregate ​ ​ Number of ​ Exercise ​ Term ​ Intrinsic ​ ​ Shares ​ Price ​ (in years) ​ Value Outstanding as of December 31, 2020 4,692,071 ​ $ 5.51 ​ Granted 1,162,918 ​ $ 2.80 ​ Exercised (623) ​ $ 2.33 ​ Cancelled (811,578) ​ $ 7.46 ​ Outstanding as of March 31, 2021 5,042,788 ​ $ 4.57 8.4 ​ $ 98,081 Exercisable as of March 31, 2021 1,042,063 ​ $ 8.21 3.9 ​ $ 11,020 Vested and expected to vest as of March 31, 2021 4,998,291 ​ $ 4.55 8.4 ​ $ 98,081
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date ​ ​ Number of ​ Fair Value ​ ​ RSUs ​ (per RSU) Nonvested as of December 31, 2020 88,131 ​ $ 4.68 Granted 334,015 ​ 2.97 Vested (10,366) ​ 3.31 Forfeited (52,403) ​ 5.59 Nonvested as of March 31, 2021 359,377 ​ $ 3.00

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment
Property, Plant and Equipment [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2021 ​ 2020 Lab and build-to-suit equipment ​ $ 7,478,278 ​ $ 7,499,645 Office equipment ​ 31,205 ​ 31,205 Furniture and fixtures ​ 257,774 ​ 257,774 Computer equipment ​ 404,558 ​ 404,558 Leasehold improvements ​ 11,524,738 ​ 11,524,738 Construction-in-progress ​ 100,820 ​ 65,820 Total property, plant and equipment ​ 19,797,373 ​ 19,783,740 Accumulated depreciation and amortization ​ (13,501,305) ​ (12,978,170) Property, plant and equipment, net ​ $ 6,296,068 ​ $ 6,805,570

Leases, Commitments and Conti_2

Leases, Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2021
Leases, Commitments and Contingencies
Lease, Cost [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ Classification 2021 2020 Operating lease cost General and administrative ​ $ 195,118 ​ $ 195,118 Finance lease cost: ​ ​ Amortization of lease assets General and administrative ​ 143,451 ​ 348,951 Interest on lease liabilities Interest expense ​ 4,972 ​ 38,903 Total Lease Cost ​ ​ ​ $ 343,541 ​ $ 582,972 ​ The weighted average remaining lease term and discount rates as of March 31, 2021 were as follows: ​ ​ ​ ​ Weighted average remaining lease term (years): ​ Operating leases 5.6 ​ Finance leases 3.0 ​ Weighted average discount rate: ​ Operating leases 10.3 % Finance leases 6.6 %
Lease Liability Maturity [Table Text Block]	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ Year ending December 31: ​ Leases ​ Leases ​ Total 2021 - nine months remaining ​ $ 907,284 ​ $ 289,774 ​ $ 1,197,058 2022 ​ 1,243,934 ​ 342,315 ​ 1,586,249 2023 ​ 1,283,253 ​ 195,180 ​ 1,478,433 2024 ​ 1,316,540 ​ 114,612 ​ 1,431,152 2025 ​ 1,355,923 ​ 64,142 ​ 1,420,065 Thereafter ​ 1,157,807 ​ — ​ 1,157,807 Total minimum lease payments ​ 7,264,741 ​ 1,006,023 ​ 8,270,764 Less: Interest ​ (1,752,099) ​ (92,112) ​ (1,844,211) Present value of lease liabilities ​ $ 5,512,642 ​ $ 913,911 ​ $ 6,426,553

Long-term Debt (Tables)

Long-term Debt (Tables)	3 Months Ended
	Mar. 31, 2021
Long-term Debt
Schedule of Long-Term Debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ Maturity Date ​ 2021 ​ 2020 Pacific Western Bank term loan ​ October 25, 2022 ​ $ — ​ $ 10,292,485 Silicon Valley Bank term loan ​ September 1, 2024 ​ ​ 10,176,481 ​ ​ — Long-term debt ​ ​ ​ $ 10,176,481 ​ $ 10,292,485
Schedule of Inputs used to Estimate Fair Value of SVB Warrant	​ ​ ​ ​ Expected dividend yield ​ — Risk-free interest rate 1.43% Expected volatility 90.8% Expected life (years) 10.0
Schedule of Annual Maturities of Long-Term Debt	​ ​ ​ ​ ​ Year ending December 31: ​ 2021 – nine months remaining ​ $ — 2022 ​ — 2023 ​ 5,250,000 2024 ​ ​ 5,250,000 Thereafter ​ — Total ​ 10,500,000 Less: Unamortized discount, debt issuance costs and accretion ​ (323,519) Less: Current portion of long-term debt ​ — Long-term debt, noncurrent ​ $ 10,176,481

Business (Details Textual)

Business (Details Textual)	Mar. 31, 2021
Business
Number of Products Under Development	1

Business - Going Concern (Detai

Business - Going Concern (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Business
Net loss	$ 9,183,153	$ 14,791,479
Accumulated deficit	$ 284,185,372		$ 275,002,219

Business - Private Placement (D

Business - Private Placement (Details) - Private Placement [Member] $ / shares in Units, $ in Millions	Apr. 13, 2021USD ($)$ / sharesshares	Apr. 13, 2021USD ($)$ / sharesshares
Private Placement
Stock Issued During Period, Shares, New Issues (in shares) | shares	8,626,037	8,626,037
Shares Issued, Price Per Share (in dollars per share) | $ / shares	$ 2.52	$ 2.52
Proceeds from Issuance of Common Stock | $	$ 21.7	$ 21.7

Basis of Presentation and Sum_3

Basis of Presentation and Summary of Significant Accounting Policies (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Cash and cash equivalents	$ 53,637,155		$ 65,316,481
Money market funds included in cash and cash equivalents	42,700,000
Cash			65,300,000
Cash equivalents			0
Accounts Receivable, Allowance for Credit Loss, Current	$ 0		$ 0
Number of reporting units	1
Revenue from Contract with Customer, Excluding Assessed Tax, Total	$ 3,083,631	$ 0
Credit Concentration Risk [Member] | Cash Held on Deposit [Member] | Pacific Western Bank [Member]
Concentration Risk, Percentage	81.50%

Basis of Presentation and Sum_4

Basis of Presentation and Summary of Significant Accounting Policies - Revision of Previously Issued Financial Statements (Details)	3 Months Ended
	Mar. 31, 2020shares
Diluted weighted average shares outstanding (in shares)	28,428,616
Previously Reported [Member]
Diluted weighted average shares outstanding (in shares)	28,322,342

Basis of Presentation and Sum_5

Basis of Presentation and Summary of Significant Accounting Policies - Common Stock Equivalent Shares Excluded From Calculation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	5,125,788	2,168,282
Share-based Payment Arrangement, Option [Member]
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	4,776,022	2,119,523
Restricted Stock Units (RSUs) [Member]
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	313,099	48,759
SVB Warrant [Member]
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	36,667

Basis of Presentation and Sum_6

Basis of Presentation and Summary of Significant Accounting Policies - Fair Value of Financial Liabilities (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Money Market Funds [Member] | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market funds	$ 42,726,954
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market funds	42,726,954
Pacific Western Bank Note, A&R LSA [Member] | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt		$ 10,292,485
Pacific Western Bank Note, A&R LSA [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt		$ 9,842,069
Silican Valley Bank Term Loan [Member] | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	10,176,481
Silican Valley Bank Term Loan [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	$ 10,072,320

Acquisition of RareGen LLC (n_3

Acquisition of RareGen LLC (now Liquidia PAH, LLC) (Details Textual) - USD ($)	Dec. 31, 2020	Nov. 18, 2020	Mar. 31, 2021
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)	$ 0.001		$ 0.001
Contract acquisition costs	$ 12,792,491		$ 12,034,436
Goodwill	$ 3,903,282		$ 3,903,282
PBM [Member] | Liquidia Corporation [Member]
Business Acquisition [Line Items]
Related Party Ownership Percentage			10.00%
Merger With RareGen LLC [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)	5,550,000	6,166,666
Common stock, par value (in dollars per share)		$ 0.001
Number of common units exchanged, representing all of the issued and outstanding RareGen equity		10,000
Cash threshold amount used to determine the pro-rata portion of RareGen cash at closing that RareGen members received		$ 1,000,000
Business Combination, Consideration Transferred, Total		$ 20,843,331
Business Acquisition, Share Price (in dollars per share)		$ 3.38
Contract acquisition costs	$ 12,792,491	$ 12,980,000	$ 12,034,436
Intangible asset		5,620,000
Business Combination, Amortization Expense			758,056
Amortization of Intangible Assets, Total			328,218
Goodwill		3,903,282
Goodwill expected to be tax deductible		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Refund Liability		2,696,000
Amount of refund liability offset against accounts receivable from Sandoz	$ 927,136		$ 826,468
Business Combination, Indemnification Assets, Amount as of Acquisition Date		$ 1,065,538
Merger With RareGen LLC [Member] | Holdback Shares [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)		616,666

Acquisition of RareGen LLC (n_4

Acquisition of RareGen LLC (now Liquidia PAH, LLC) - Purchase Price (Details) - Merger With RareGen LLC [Member] - USD ($)	Dec. 31, 2020	Nov. 18, 2020
Business Acquisition [Line Items]
Number of common shares to be issued to RareGen's members (in shares)	5,550,000	6,166,666
Multiplied by the fair value per share of Liquidia Technologies common stock (in dollars per share)		$ 3.38
Total estimated purchase price		$ 20,843,331

Acquisition of RareGen LLC (n_5

Acquisition of RareGen LLC (now Liquidia PAH, LLC) - Purchase Price Allocation (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020	Nov. 18, 2020
Business Acquisition [Line Items]
Contract acquisition costs	$ 12,034,436	$ 12,792,491
Goodwill	3,903,282	3,903,282
Merger With RareGen LLC [Member]
Business Acquisition [Line Items]
Cash			$ 1,000,000
Property and equipment			79,330
Prepaid and other current assets			30,190
Intangible asset			5,620,000
Contract acquisition costs	$ 12,034,436	$ 12,792,491	12,980,000
Indemnification asset			1,065,538
Goodwill			3,903,282
Less other current liabilities			(492,499)
Less refund liability			(2,696,000)
Less litigation finance payable, current			(646,510)
Total estimated purchase price			$ 20,843,331

Stockholders' Equity Authoriz_3

Stockholders' Equity Authorized Capital (Details Textual) - USD ($) $ / shares in Units, $ in Millions	Apr. 13, 2021	Sep. 29, 2020	Jul. 02, 2020	Aug. 31, 2019	Apr. 13, 2021	Mar. 31, 2021	Mar. 31, 2020	Feb. 26, 2021	Dec. 31, 2020
Common Stock and Preferred Stock, Shares Authorized (in shares)						90,000,000
Common Stock and Preferred Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001
Common Stock, Shares Authorized (in shares)						80,000,000			80,000,000
Preferred Stock, Shares Authorized (in shares)						10,000,000			10,000,000
Class of Warrant or Right, Exercised During Period (in shares)						0	0
SVB Warrant [Member]
Class of Warrant or Right, Outstanding (in shares)						100,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 3.05		$ 3.05
Other Warrants [Member]
Class of Warrant or Right, Outstanding (in shares)						106,274			106,274
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 0.02			$ 0.02
Underwritten Public Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)		9,375,000
Shares Issued, Price Per Share (in dollars per share)		$ 8
Proceeds from Issuance of Common Stock			$ 70.3
Private Placement [Member]
Stock Issued During Period, Shares, New Issues (in shares)	8,626,037				8,626,037
Shares Issued, Price Per Share (in dollars per share)	$ 2.52				$ 2.52
Proceeds from Issuance of Common Stock	$ 21.7				$ 21.7
ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)							131,425
Proceeds from Issuance of Common Stock, Net							$ 0.7
ATM Agreement [Member] | Jefferies, LLC [Member]
Sale of Stock, Maximum Aggregate Offering Price				$ 40
Sale of Stock, Commission Percentage				3.00%

Stock-Based Compensation (Detai

Stock-Based Compensation (Details Textual) - USD ($)	Jan. 01, 2021	Dec. 31, 2020	Nov. 30, 2020	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)				1,162,918
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)				$ 2.80
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)				$ 2.09	$ 2.38
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)				623
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				4 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				334,015	138,464
Common Stock [Member]
Share Price (in dollars per share)				$ 2.69
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)				281	2,035
Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)		2,000,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)		$ 3
Chief Executive Officer [Member] | Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		36 months
Chief Executive Officer [Member] | Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		25.00%
Chief Executive Officer [Member] | Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		25.00%
Chief Executive Officer [Member] | Share-based Payment Arrangement, Tranche One, Two, Three, and Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		100.00%
The 2020 Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)			1,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Percent Annual Increase in Capital Shares Reserved for Future Issuance			4.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	1,733,432
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	2,955,432	1,222,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)				1,582,139
The 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)				989,923
The 2016 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)				351,552
The 2004 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)				209,397
The ESPP [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)				300,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent				85.00%
Employee Stock Purchase Plan, Maximum Contribution Per Eligible Employee				$ 25,000

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Stock-based compensation expense	$ 745,000	$ 878,963
Share-based Payment Arrangement, Option [Member]
Stock-based compensation expense	762,000	854,770
Restricted Stock Units (RSUs) [Member]
Stock-based compensation expense	(17,000)	24,193
Research and Development Expense [Member]
Stock-based compensation expense	251,000	275,141
General and Administrative Expense [Member]
Stock-based compensation expense	$ 494,000	$ 603,822

Stock-Based Compensation - Unam

Stock-Based Compensation - Unamortized Compensation Expense (Details)	3 Months Ended
	Mar. 31, 2021USD ($)
Share-based Payment Arrangement, Option [Member]
Stock-based awards, unamortized expense	$ 9,859,000
Stock-based awards, weighted average remaining recognition period (Year)	3 years 4 months 24 days
Restricted Stock Units (RSUs) [Member]
Stock-based awards, unamortized expense	$ 865,000
Stock-based awards, weighted average remaining recognition period (Year)	1 year 9 months 18 days

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value Assumptions (Details)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Expected dividend yield	0.00%
Risk-free interest rate, minimum	0.62%	0.90%
Risk-free interest rate, maximum	1.67%	1.60%
Expected Volatility, minimum	93.00%	87.00%
Expected Volatility, maximum	94.00%	90.00%
Expected life (years) (Year)		6 years 1 month 6 days
Minimum [Member]
Expected life (years) (Year)	5 years 2 months 12 days
Maximum [Member]
Expected life (years) (Year)	6 years 1 month 6 days

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock Option Activity (Details)	3 Months Ended
	Mar. 31, 2021USD ($)$ / sharesshares
Stock-Based Compensation
Outstanding, number of shares (in shares) | shares	4,692,071
Outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 5.51
Granted, number of shares (in shares) | shares	1,162,918
Granted, weighted average exercise price (in dollars per share) | $ / shares	$ 2.80
Exercised, number of shares (in shares) | shares	(623)
Exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 2.33
Cancelled, number of shares (in shares) | shares	(811,578)
Cancelled, weighted average exercise price (in dollars per share) | $ / shares	$ 7.46
Outstanding, number of shares (in shares) | shares	5,042,788
Outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 4.57
Outstanding, weighted average contractual term (Year)	8 years 4 months 24 days
Outstanding, aggregate intrinsic value | $	$ 98,081
Exercisable, number of shares (in shares) | shares	1,042,063
Exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 8.21
Exercisable, weighted average contractual term (Year)	3 years 10 months 24 days
Exercisable, aggregate intrinsic value | $	$ 11,020
Vested and expected to vest, number of shares (in shares) | shares	4,998,291
Vested and expected to vest, weighted average exercise price (in dollars per share) | $ / shares	$ 4.55
Vested and expected to vest, weighted average contractual term (Year)	8 years 4 months 24 days
Vested and expected to vest, aggregate intrinsic value | $	$ 98,081

Stock-Based Compensation - Nonv

Stock-Based Compensation - Nonvested RSU Awards Outstanding (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Nonvested, number (in shares)	88,131
Nonvested , weighted average grant date fair value (in dollars per share)	$ 4.68
Granted, number (in shares)	334,015	138,464
Granted , weighted average grant date fair value (in dollars per share)	$ 2.97
Vested , number (in shares)	(10,366)
Vested , weighted average grant date fair value (in dollars per share)	$ 3.31
Forfeited, number (in shares)	(52,403)
Forfeited , weighted average grant date fair value (in dollars per share)	$ 5.59
Nonvested , number (in shares)	359,377
Nonvested , weighted average grant date fair value (in dollars per share)	$ 3

Revenue From Contracts With C_2

Revenue From Contracts With Customers (Details Textual) - USD ($)	Aug. 01, 2018	Mar. 31, 2021	Mar. 31, 2020
Revenue from Contract with Customer, Excluding Assessed Tax, Total		$ 3,083,631	$ 0
Sandoz [Member]
Promotion Agreement, Payment	$ 20,000,000

Revenue From Contracts With C_3

Revenue From Contracts With Customers - Disaggregation of Revenue (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue From Contracts With Customers
Revenue	$ 3,083,631	$ 0

Property, Plant and Equipment_2

Property, Plant and Equipment (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Property, Plant and Equipment
Depreciation, Depletion and Amortization, Nonproduction, Total	$ 523,135	$ 732,029

Property, Plant and Equipment -

Property, Plant and Equipment - Property, Plant and Equipment (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Total property, plant and equipment	$ 19,797,373	$ 19,783,740
Accumulated depreciation and amortization	(13,501,305)	(12,978,170)
Property, plant and equipment, net	6,296,068	6,805,570
Lab and Build-to-Suit Equipment [Member]
Total property, plant and equipment	7,478,278	7,499,645
Office Equipment [Member]
Total property, plant and equipment	31,205	31,205
Furniture and Fixtures [Member]
Total property, plant and equipment	257,774	257,774
Computer Equipment [Member]
Total property, plant and equipment	404,558	404,558
Leasehold Improvements [Member]
Total property, plant and equipment	11,524,738	11,524,738
Construction in Progress [Member]
Total property, plant and equipment	$ 100,820	$ 65,820

Income Taxes (Details Textual)

Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Taxes
Income Tax Expense (Benefit), Total	$ 0	$ 0

Leases, Commitments and Conti_3

Leases, Commitments and Contingencies (Details Textual)	3 Months Ended
	Mar. 31, 2021USD ($)ft²	Feb. 28, 2021	Jan. 31, 2021	Nov. 18, 2020shares
Lessee, Finance Lease, Discount Rate		6.50%	7.50%
Maximum Net Sales Threshold As Basis For Payment Of Future Contingent Royalties	$ 1,500,000
Agreement With LGM Pharma, LLC [Member]
Purchase Commitment, Remaining Minimum Amount Committed	$ 3,050,000
Minimum [Member]
Lessee, Finance Lease, Remaining Lease Term		24 months
Maximum [Member]
Lessee, Finance Lease, Remaining Lease Term		48 months
Merger With RareGen LLC [Member] | Maximum [Member]
Business Acquisition, Number of Additional Shares Issuable Upon Achievement of Sales Target (in shares) | shares				2,708,333
Primary Building in Morrisville, North Carolina [Member]
Area of Real Estate Property (Square Foot) | ft²	45,000

Leases, Commitments and Conti_4

Leases, Commitments and Contingencies - Lease Cost and Other (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Total Lease Cost	$ 343,541	$ 582,972
Operating leases (Year)	5 years 7 months 6 days
Finance leases (Year)	3 years
Operating leases	10.30%
Finance leases	6.60%
General and Administrative Expense [Member]
Operating lease cost	$ 195,118	195,118
Amortization of lease assets	143,451	348,951
Interest Expense [Member]
Interest on lease liabilities	$ 4,972	$ 38,903

Leases, Commitments and Conti_5

Leases, Commitments and Contingencies - Future Minimum Lease Payments (Details)	Mar. 31, 2021USD ($)
Operating Leases
2021 - nine months remaining	$ 907,284
2022	1,243,934
2023	1,283,253
2024	1,316,540
2025	1,355,923
Thereafter	1,157,807
Total minimum lease payments	7,264,741
Less: Interest	(1,752,099)
Present value of lease liabilities	5,512,642
Finance Leases
2021 - nine months remaining	289,774
2022	342,315
2023	195,180
2024	114,612
2025	64,142
Total minimum lease payments	1,006,023
Less: Interest	(92,112)
Present value of lease liabilities	913,911
Total
2021 - nine months remaining	1,197,058
2022	1,586,249
2023	1,478,433
2024	1,431,152
2025	1,420,065
Thereafter	1,157,807
Total minimum lease payments	8,270,764
Less: Interest	(1,844,211)
Present value of lease liabilities	$ 6,426,553

Long-term Debt (Details Textual

Long-term Debt (Details Textual) - USD ($)	Mar. 01, 2021	Feb. 26, 2021	Mar. 31, 2021	Mar. 31, 2020	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Proceeds from Issuance of Long-term Debt, Total			$ 10,410,269	$ 0
Long-term Debt, Gross			$ 10,500,000
Common Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.001							$ 0.001
SVB Warrant [Member]
Debt Instrument [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)		200,000
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001
Class of Warrant or Right, Number of Securities Vested (in shares)		100,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 3.05	$ 3.05
Class of Warrant or Right, Outstanding (in shares)			100,000
Warrants and Rights Outstanding, Term (Year)		10 years
Fair value of the warrant included in additional paid-in-capital			$ 261,000
Warrants to Vest in Connection with Term B Loan Funding Date [Member]
Debt Instrument [Line Items]
Class of Warrant or Right, Outstanding (in shares)		50,000
Warrants to Vest in Connection with Term C Loan Funding Date [Member]
Debt Instrument [Line Items]
Class of Warrant or Right, Outstanding (in shares)		50,000
Pacific Western Bank Note, A&R LSA [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 9,400,000
Loss on extinguishment of debt			53,150
Loan and Security Agreement with SVB [Member]
Debt Instrument [Line Items]
Minimum Cash Balance to be Maintained		$ 30,000,000
Minimum Cash Balance to be Maintained Commencing on the Term B Loan Funding Date		$ 35,000,000
Debt Instrument, Cumulative Cash Burn			10,500,000
Debt Instrument, Cumulative Cash Burn, Conditional Increase, Percent		75.00%
Loan and Security Agreement with SVB [Member] | Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Cumulative Cash Burn					$ 38,000,000	$ 33,500,000	$ 28,500,000	$ 23,000,000	$ 17,000,000
Silican Valley Bank Term Loan [Member]
Debt Instrument [Line Items]
Maximum Borrowing Capacity		$ 20,500,000
Percentage of the aggregate principal amount of all Term loans made by SVB to be paid (the "Final Payment")		5.00%
Debt Instrument, Prepayment Penalty Fee Percentage		5.00%
Silican Valley Bank Term Loan [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.00%
Silican Valley Bank Term Loan [Member] | Prime Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.75%
Term A Loan
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 10,500,000
Fair value of term loan			$ 10,239,000
Debt, fees incurred		$ 88,000
Term B Loan
Debt Instrument [Line Items]
Borrowing capacity available, conditioned upon the Company meeting certain requirements		5,000,000
Term C Loan
Debt Instrument [Line Items]
Borrowing capacity available, conditioned upon the Company meeting certain requirements		$ 5,000,000

Long-term Debt - Summary (Detai

Long-term Debt - Summary (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 10,176,481	$ 10,292,485
Pacific Western Bank Note, A&R LSA [Member]
Debt Instrument [Line Items]
Long-term debt		$ 10,292,485
Silican Valley Bank Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt	$ 10,176,481

Long-term Debt - SVB Warrant (D

Long-term Debt - SVB Warrant (Details) - SVB Warrant [Member]	Mar. 31, 2021USD ($)
Measurement Input, Risk Free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.0143
Measurement Input, Price Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.908
Measurement Input, Exercise Price [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	10

Long-term Debt - Maturities (De

Long-term Debt - Maturities (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Scheduled annual maturities of long-term debt
2023	$ 5,250,000
2024	5,250,000
Thereafter	0
Total	10,500,000
Less: Unamortized discount, debt issuance costs and accretion	(323,519)
Long-term debt, noncurrent	$ 10,176,481	$ 10,292,485