Liquidia (LQDA) 10-K 13 Mar 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2023	Mar. 11, 2024	Jun. 30, 2023
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	001-39724
Entity Registrant Name	LIQUIDIA CORPORATION
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 Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 368,576,944
Entity Common Stock, Shares Outstanding		76,027,776
Auditor Firm ID	238
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Raleigh, North Carolina
Entity Central Index Key	0001819576
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 83,679	$ 93,283
Accounts receivable, net	4,061	5,017
Prepaid expenses and other current assets	2,159	1,511
Total current assets	89,899	99,811
Property, plant and equipment, net	4,480	4,151
Operating lease right-of-use assets, net	1,704	2,101
Indemnification asset, related party	6,707	6,595
Contract acquisition costs, net	7,922	8,604
Intangible asset, net	3,430	3,726
Goodwill	3,903	3,903
Other assets	287	307
Total assets	118,332	129,198
Current liabilities:
Accounts payable	1,396	2,197
Accrued expenses and other current liabilities	13,400	5,522
Revenue interest financing payable, current	2,615
Operating lease liabilities, current	1,032	900
Finance lease liabilities, current	107	181
Total current liabilities	18,550	8,800
Litigation finance payable	6,707	6,594
Revenue interest financing payable, noncurrent	43,418
Operating lease liabilities, noncurrent	2,300	3,332
Finance lease liabilities, noncurrent	64	171
Long-term debt		19,879
Total liabilities	71,039	38,776
Commitments and contingencies (Note 16)
Stockholders' equity:
Preferred stock - 10,000,000 shares authorized, none outstanding
Common stock - $0.001 par value, 100,000,000 and 80,000,000 shares authorized as of December 31, 2023 and December 31, 2022, respectively, 68,629,575 and 64,517,912 shares issued and outstanding as of December 31, 2023 and December 31, 2022, respectively	69	64
Additional paid-in capital	476,322	440,954
Accumulated deficit	(429,098)	(350,596)
Total stockholders' equity	47,293	90,422
Total liabilities and stockholders' equity	$ 118,332	$ 129,198

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Consolidated Balance Sheets
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
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)	100,000,000	80,000,000
Common stock, shares issued (in shares)	68,629,575	64,517,912
Common stock, shares outstanding (in shares)	68,629,575	64,517,912

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Consolidated Statements of Operations and Comprehensive Loss
Revenue	$ 17,488	$ 15,935
Costs and expenses:
Cost of revenue	2,888	2,859
Research and development	43,242	19,435
General and administrative	44,742	32,411
Total costs and expenses	90,872	54,705
Loss from operations	(73,384)	(38,770)
Other income (expense):
Interest income	3,466	1,090
Interest expense	(6,273)	(2,338)
Loss on extinguishment of debt	(2,311)	(997)
Total other expense, net	(5,118)	(2,245)
Net loss and comprehensive loss	$ (78,502)	$ (41,015)
Net loss per common share, basic (in dollars per share)	$ (1.21)	$ (0.67)
Net loss per common share, diluted (in dollars per share)	$ (1.21)	$ (0.67)
Weighted average common shares outstanding, basic (in shares)	64,993,476	60,958,862
Weighted average common shares outstanding, diluted (in shares)	64,993,476	60,958,862

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Total
Balance at Dec. 31, 2021	$ 52	$ 374,794	$ (309,581)	$ 65,265
Balance (in shares) at Dec. 31, 2021	52,287,737
Issuance of common stock upon exercise of stock options		838		838
Issuance of common stock upon exercise of stock options (in shares)	232,877
Issuance of common stock upon vesting of restricted stock units (in shares)	54,181
Issuance of common stock under employee stock purchase plan		258		258
Issuance of common stock under employee stock purchase plan (in shares)	51,941
Issuance of warrant		1,317		1,317
Equity consideration for acquisition	$ 1	(1)
Equity consideration for acquisition (in shares)	616,666
Sale of common stock, net	$ 11	54,450		54,461
Sale of common stock, net (in shares)	11,274,510
Stock-based compensation		9,298		9,298
Net loss			(41,015)	(41,015)
Balance at Dec. 31, 2022	$ 64	440,954	(350,596)	90,422
Balance (in shares) at Dec. 31, 2022	64,517,912
Issuance of common stock upon exercise of stock options		495		$ 495
Issuance of common stock upon exercise of stock options (in shares)	137,576			137,576
Issuance of common stock upon vesting of restricted stock units	$ 1	(1)
Issuance of common stock upon vesting of restricted stock units (in shares)	201,880
Issuance of common stock under employee stock purchase plan		683		$ 683
Issuance of common stock under employee stock purchase plan (in shares)	140,922
Sale of common stock, net	$ 4	24,102		24,106
Sale of common stock, net (in shares)	3,631,285
Stock-based compensation		10,089		10,089
Net loss			(78,502)	(78,502)
Balance at Dec. 31, 2023	$ 69	$ 476,322	$ (429,098)	$ 47,293
Balance (in shares) at Dec. 31, 2023	68,629,575

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating activities
Net loss	$ (78,502)	$ (41,015)
Adjustments to reconcile net loss to net cash used in operating activities:
Acquired in-process research and development	10,000
Stock-based compensation	10,089	9,298
Depreciation and amortization	2,178	3,647
Non-cash lease expense	397	311
Loss (gain) on disposal of property and equipment	(2)	4
Loss on extinguishment of debt	2,311	997
Accretion and non-cash interest expense	6,093	328
Changes in operating assets and liabilities:
Accounts receivable, net	956	(2,027)
Prepaid expenses and other current assets	(798)	(719)
Other noncurrent assets	20	4
Accounts payable	(1,152)	814
Accrued expenses and other current liabilities	7,746	545
Operating lease liabilities	(900)	(775)
Net cash used in operating activities	(41,564)	(28,588)
Investing activities
Purchase of in-process research and development	(10,000)
Purchases of property, plant and equipment	(1,290)	(592)
Proceeds from the sale of property, plant and equipment	2	5
Net cash used in investing activities	(11,288)	(587)
Financing activities
Proceeds from revenue interest financing, net	41,744
Principal payments on long-term debt	(20,000)	(10,500)
Payments for debt prepayment and extinguishment costs	(2,190)
Payments	(1,654)
Proceeds from issuance of long-term debt with warrants, net		19,767
Principal payments on finance leases	(181)	(311)
Receipts from litigation financing	113	451
Proceeds from sale of common stock, net of issuance costs	24,238	54,461
Proceeds from issuance of common stock under stock incentive plans	1,178	1,096
Net cash provided by financing activities	43,248	64,964
Net increase (decrease) in cash and cash equivalents	(9,604)	35,789
Cash and cash equivalents, beginning of period	93,283	57,494
Cash and cash equivalents, end of period	83,679	93,283
Supplemental disclosure of cash flow information
Cash paid for interest	360	1,626
Cash paid for operating lease liabilities	1,283	1,244
Offering costs incurred, but not paid included in accrued expenses	132
Non-cash increase in property, plant and equipment through accounts payable	239	139
Non-cash increase in indemnification asset through accounts payable	$ 112	$ 313

Basis of Presentation, Signific

Basis of Presentation, Significant Accounting Policies and Fair Value Measurements	12 Months Ended
	Dec. 31, 2023
Basis of Presentation, Significant Accounting Policies and Fair Value Measurements
Basis of Presentation, Significant Accounting Policies and Fair Value Measurements	2. Basis of Presentation, Significant Accounting Policies and Fair Value Measurements Basis of Presentation These consolidated financial statements, 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”). Our financial position, results of operations and cash flows are presented in U.S. Dollars. Consolidation The accompanying consolidated financial statements include our 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 to be reasonable under the circumstances. We evaluate our estimates on an ongoing basis, including those related to the valuation of stock-based awards, certain accruals, the revenue interest financing payable, and intangible and contract acquisition cost amortization, and make changes to the estimates and related disclosures as our experience develops or new information becomes known. Actual results will most likely differ from those estimates. Segment Information GAAP requires segmentation based on an entity’s internal organization and reporting of revenue and operating income based upon internal accounting methods commonly referred to as the “management approach.” Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker (CODM), or decision-making group, in deciding how to allocate resources and in assessing performance. Our CODM is our Chief Executive Officer. We have determined that we have one operating and reporting segment. Summary of Significant Accounting Policies Recent Accounting Pronouncements In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Subtopic 280) . This guidance The guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal periods beginning after December 15, 2024. We are in the process of evaluating the impact of this guidance on our consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Subtopic 740) . This guidance The guidance is effective for fiscal years beginning after December 15, 2024. We are in the process of evaluating the impact of this guidance on our consolidated financial statements and related disclosures. Cash, Cash Equivalents, and Concentration of Credit Risk We consider all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. Financial instruments that potentially subject us to concentrations of credit risk consist of cash and cash equivalents. We are exposed to credit risk, subject to federal deposit insurance, in the event of default by the financial institutions holding our cash and cash equivalents to the extent of amounts recorded on the consolidated balance sheet. As of December 31, 2022, all of our cash and cash equivalents were held with Silicon Valley Bank (“SVB”). Following the March 10, 2023 Federal Deposit Insurance Corporation takeover of SVB, substantially all of our cash and cash equivalents have been moved to multiple accredited financial institutions. We have not experienced any losses on such accounts and do not believe that we are subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Such deposits have exceeded and will continue to exceed federally insured limits. Accounts Receivable Accounts receivable are stated at net realizable value and net of an allowance for credit losses as of each balance sheet date, if applicable. As of December 31, 2023 and 2022, one customer accounted for 99% of our accounts receivable, net. As of December 31, 2023 and 2022, we have not recorded an allowance for credit losses. Prelaunch Inventory We capitalize prelaunch inventory prior to receiving regulatory approval if regulatory approval and subsequent commercialization of a product is probable and we also expect future economic benefit from the sales of the product to be realized. Prior to this, we expense prelaunch inventory as research and development expense in the period incurred. For prelaunch inventory that is capitalized, we consider a number of specific facts and circumstances, including the product’s historical shelf life, the product's current status in the development and regulatory approval process, results from related clinical trials, results from meetings with relevant regulatory agencies prior to the filing of regulatory applications, potential obstacles to the approval process, historical experience, viability of commercialization and market trends. No prelaunch inventory was capitalized as of December 31, 2023. Leases ASC 842 Leases is expensed over the lease term on a straight-line basis, with all cash flows classified as an operating activity in the Statement of Cash Flows. For finance leases, interest on the lease liability is recognized separately from the amortization of the right-of-use asset in the Statement of Operations and Comprehensive Loss and the repayment of the principal portion of the lease liability is classified as a financing activity, while the interest component is classified as an operating activity in the Statement of Cash Flows. Property, Plant and Equipment Property, plant and equipment are stated at cost. Depreciation of property, plant and equipment is computed using the straight-line method over the estimated useful lives of the assets beginning when the assets are placed in service. Estimated useful lives for the major asset categories are: ​ ​ ​ ​ Lab and build-to-suit equipment (years) 5 - 7 Office equipment (years) ​ 5 Furniture and fixtures (years) ​ 10 Computer equipment (years) ​ 3 Leasehold improvements Lesser of life of the asset or remaining lease term ​ Major renewals and improvements are capitalized to the extent that they increase the useful economic life or increase the expected economic benefit of the underlying asset. Maintenance and repairs are charged to operations as incurred. When items of property, plant and equipment are sold or retired, the related cost and accumulated depreciation or amortization is removed from the accounts, and any gain or loss is included in operating expenses in the accompanying Statements of Operations and Comprehensive Loss. Long-Lived Assets We review 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. We also review for impairment when conditions exist that indicate the carrying amount of the assets may not be fully recoverable. In those circumstances, we perform undiscounted operating cash flow analyses to determine if an impairment exists. When testing for asset impairment, we group 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 We assess 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. For example, significant and unanticipated changes or our inability to obtain or maintain regulatory approvals for our product candidates, including the NDA for YUTREPIA, could trigger testing of our goodwill for impairment at an interim date. We have one reporting unit. We have 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 ASC 350 Intangibles-Goodwill and Other We completed our annual goodwill impairment test as of July 1, 2023. There have been no significant events or circumstances affecting the valuation of goodwill subsequent to the assessment. Revenue Interest Financing Payable We recognized a liability related to amounts received in January 2023 and July 2023 pursuant to the RIFA under ASC 470-10, Debt Interest - Imputation of Interest Revenue Recognition We recognize revenue in accordance with ASC 606, Revenue from Contracts with Customers ● 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, we assess the promised goods or services in the contract and identify 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. We evaluate 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. We recognize 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. Research and Development Expense Research and development costs are expensed as incurred in accordance with ASC 730, Research and Development Patent Maintenance We are responsible for all patent costs, past and future, associated with the preparation, filing, prosecution, issuance, maintenance, enforcement and defense of United States patent applications to which we have rights other than those patents that we license from Pharmosa that are not specific to L606. Such costs are recorded as general and administrative expenses as incurred. To the extent that our licensees share these costs, such benefit is recorded as a reduction of the related expenses. Stock-Based Compensation We estimate the grant date fair value of stock-based awards and amortize this fair value to compensation expense over the requisite service period or the vesting period of the respective award. In arriving at stock-based compensation expense, we estimate the number of stock-based awards that will be forfeited due to employee turnover. The forfeiture assumption is based primarily on turn-over historical experience. If the actual forfeiture rate is higher than the estimated forfeiture rate, then an adjustment will be made to increase the estimated forfeiture rate, which will result in a decrease to the expense recognized in our financial statements. If the actual forfeiture rate is lower than the estimated forfeiture rate, then an adjustment will be made to lower the estimated forfeiture rate, which will result in an increase to expense recognized in our financial statements. The expense we recognize in future periods will be affected by changes in the estimated forfeiture rate and may differ from amounts recognized in the current period. See Note 8. 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 weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. Due to their anti-dilutive effect, the calculation of diluted net loss per share excludes the following common stock equivalent shares: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ ​ 2023 ​ 2022 Stock Options 9,513,039 7,757,017 Restricted Stock Units 1,685,532 399,349 Warrants ​ 450,000 ​ 445,205 Total 11,648,571 8,601,571 ​ Certain common stock warrants are included in the calculation of basic and diluted net loss per share since their exercise price is de minimis. Income Taxes The asset and liability method is used in our accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. We record a valuation allowance against deferred tax assets when realization of the tax benefit is uncertain. A valuation allowance is recorded, if necessary, to reduce net deferred taxes to their realizable values if management believes it is more likely than not that the net deferred tax assets will not be realized. We may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities based on the technical merits of the position. The tax benefits recognized in the financial statements from such a position are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement. Fair Value Measurements ASC 825 Financial Instruments Level 1 — Quoted prices in active markets for identical assets or liabilities; Level 2 — Inputs other than quoted prices included in active markets 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 table presents the placement in the fair value hierarchy of financial assets and liabilities measured at fair value as of December 31, 2023 and December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2023 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Money market funds (cash equivalents) ​ $ 79,912 ​ $ — ​ $ — ​ $ 79,912 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2022 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Money market funds (cash equivalents) ​ $ 92,283 ​ $ — ​ $ — ​ $ 92,283 ​ Money market funds are included in cash and cash equivalents on our consolidated balance sheet and are classified within Level 1 of the fair value hierarchy since they are valued using quoted market prices. The carrying amounts reflected in our consolidated balance sheets for cash, accounts receivable, 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 carrying value of long-term debt and the revenue interest financing payable approximate fair value as the respective interest rates are reflective of current market rates on debt with similar terms and conditions. In addition, the revenue interest financing payable is updated with the expected amount to be paid back each reporting period based on the contractual terms and current projections.

Property, Plant, and Equipment

Property, Plant, and Equipment	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment
Property, Plant and Equipment	3. Property, Plant and Equipment Property, plant and equipment consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, ​ ​ 2023 ​ 2022 Lab and build-to-suit equipment ​ $ 6,834 ​ $ 6,257 Office equipment ​ 19 ​ 19 Furniture and fixtures ​ 241 ​ 134 Computer equipment ​ 487 ​ 291 Leasehold improvements ​ 11,409 ​ 11,409 Construction-in-progress ​ 804 ​ 155 Total property, plant and equipment ​ 19,794 ​ 18,265 Accumulated depreciation and amortization ​ (15,314) ​ (14,114) Property, plant and equipment, net ​ $ 4,480 ​ $ 4,151 ​ We recorded depreciation and amortization expense related to property, plant and equipment

Contract Acquisition Costs and

Contract Acquisition Costs and Intangible Asset, and Goodwill	12 Months Ended
	Dec. 31, 2023
Contract Acquisition Costs and Intangible Asset, and Goodwill
Contract Acquisition Costs and Intangible Asset, and Goodwill	4. Contract Acquisition Costs and Intangible Asset, and Goodwill Contract acquisition costs and intangible asset are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 ​ ​ Gross Carrying Amount ​ Accumulated Amortization ​ Net Carrying Amount ​ Gross Carrying Amount ​ Accumulated Amortization ​ Net Carrying Amount Contract acquisition costs ​ $ 12,980 ​ $ (5,058) ​ $ 7,922 ​ $ 12,980 ​ $ (4,376) ​ $ 8,604 Intangible asset ​ $ 5,620 ​ $ (2,190) ​ $ 3,430 ​ $ 5,620 ​ $ (1,894) ​ $ 3,726 ​ We are amortizing the value of the 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 November 18, 2020 through December 2032, the termination date of the Promotion Agreement (see Note 2-Revenue Recognition for our accounting policies). Amortization of contract acquisition costs is recorded as a reduction of revenue, and amortization of the intangible asset is recorded as cost of revenue. We recorded amortization related to the contract acquisition costs of $0.7 million and $1.5 million for the years ended December 31, 2023 and 2022, respectively. We recorded amortization related to the intangible asset of $0.3 million and $0.7 million for the years ended December 31, 2023 and 2022, respectively. Annual amortization over the next five years is expected to immaterially fluctuate from the 2023 amounts, consistent with changes to net profits to be recognized pursuant to the Promotion Agreement over the period. During the year ended December 31, 2020, we recorded goodwill of $3.9 million, which primarily represented the Liquidia PAH assembled workforce and the residual value of the purchase consideration and assumed liabilities that exceeded the assets acquired (see Note 2-Goodwill). As of December 31, 2023 and 2022, we concluded that there were no events or changes in circumstances that indicated that the carrying amount of goodwill was not recoverable.

Indemnification Asset with Rela

Indemnification Asset with Related Party and Litigation Finance Payable	12 Months Ended
	Dec. 31, 2023
Indemnification Asset with Related Party and Litigation Finance Payable
Indemnification Asset with Related Party and Litigation Finance Payable	5. Indemnification Asset with Related Party and Litigation Finance Payable On June 3, 2020, 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”) (the “RareGen Litigation”). 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 (as defined below), all proceeds received by Liquidia PAH are due to PBM as described further below. On November 17, 2020, Liquidia PAH entered into a Litigation Funding and Indemnification Agreement (“Indemnification Agreement”) with PBM RG Holdings, LLC (“PBM”). PBM is considered to be a related party as it is controlled by a major stockholder (which beneficially owns approximately 8.3% of Liquidia Corporation Common Stock as of March 1, 2024), who is also a member of our Board of Directors. Under the terms of the Indemnification Agreement, PBM now controls the litigation, with Liquidia PAH’s primary 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 RareGen 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. The Indemnification Asset is increased as we record third party legal and litigation expenses related to the United Therapeutics and Smiths Medical litigation. As of December 31, 2023, the Indemnification Asset and Litigation Finance Payable were classified as long-term assets and liabilities, respectively, as it is considered unlikely that the RareGen Litigation would conclude prior to December 31, 2024.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2023
Accrued Expenses and Other Current Liabilities
Accrued Expenses and Other Current Liabilities	6. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2023 2022 Accrued compensation ​ $ 8,544 ​ $ 2,862 Accrued research and development expenses ​ ​ 2,902 ​ ​ 1,757 Accrued other expenses ​ ​ 1,954 ​ ​ 903 Total accrued expenses and other current liabilities ​ $ 13,400 ​ $ 5,522 ​

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity
Stockholders' Equity	7. Stockholders’ Equity Authorized Capital As of December 31, 2023, the authorized capital of the Company consists of 110,000,000 shares of capital stock, $0.001 par value per share, of which 100,000,000 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 December 12, 2023 from an Underwritten Public Offering and Private Placement In December 2023, we sold 3,491,620 shares of our common stock in an underwritten registered public offering at an offering price of $7.16 per share (the “2023 Offering”) for net proceeds of approximately $25.0 million, before deducting offering costs of approximately $1.9 million. Caligan Partners LP (“Caligan”), our largest stockholder, and Paul B. Manning, members of our Board of Directors, participated in the 2023 Offering and purchased shares of common stock in an aggregate amount of approximately $10.0 million at the public offering price per share and on the same terms as the other purchasers in the 2023 Offering. Caligan purchased Concurrently with the 2023 Offering referenced above, we entered into a common stock purchase agreement with Roger Jeffs, our Chief Executive Officer, for the sale by us in a private placement of an aggregate of 139,665 shares of our common stock at a purchase price of $7.16 per share for gross proceeds of approximately $1.0 million. Issuance of Common Stock on April 18, 2022 from an Underwritten Public Offering In April 2022, we sold 11,274,510 shares of our common stock in an underwritten registered public offering at an offering price of $5.10 per share (the “2022 Offering”) for net proceeds of approximately $54.5 million, after deducting offering costs. Caligan and Paul B. Manning participated in the 2022 Offering and purchased shares of common stock in an aggregate amount of $11.0 million at the public offering price per share and on the same terms as the other purchasers in the 2022 Offering. Caligan purchased 1,764,705 shares of common stock in the 2022 Offering for an aggregate purchase price of $9.0 million and Paul B. Manning purchased 392,156 shares of common stock in the 2022 Offering for an aggregate purchase price of $2.0 million. Issuance of Common Stock on March 31, 2022 from Merger Transaction On November 18, 2020 (the “Closing Date”), we completed the acquisition of RareGen as contemplated by that certain 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”). On the Closing Date, an aggregate of 5,550,000 shares of our common stock, were issued to RareGen members in exchange for all of the issued and outstanding RareGen equity. On March 31, 2022, an aggregate of 616,666 additional shares of our common stock, which were held back on the Closing Date for indemnification purposes, were issued to RareGen members. Warrants During the years ended December 31, 2023 and 2022, no warrants to purchase shares of common stock were exercised. Outstanding warrants consisted of the following as of December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ ​ ​ ​ ​ ​ warrants Exercise Price Expiration Date A&R SVB Warrant (see Note 13) ​ 250,000 ​ $ 5.14 ​ January 6, 2032 SVB Warrant - Initial Tranche (see Note 13) ​ 100,000 ​ $ 3.05 ​ February 26, 2031 SVB Warrant - Term B and Term C Tranches (see Note 13) ​ 100,000 ​ $ n/a ​ February 26, 2031 Other warrants ​ 65,572 ​ $ 0.02 ​ December 31, 2026 ​

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2023
Stock-Based Compensation
Stock-Based Compensation	8. Stock-Based Compensation 2020 Long-Term Incentive Plan Our 2020 Long-Term Incentive Plan (the “2020 Plan”) provides for the granting of stock appreciation rights, stock awards, stock units, and other stock-based awards and for accelerated vesting under certain change of control transactions. The number of shares of our common stock available for issuance under the 2020 plan will automatically increase on January 1 of each year 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, 2024, the number of shares of common stock available for issuance under the 2020 Plan automatically increased by 2,745,183 shares pursuant to the Evergreen Provision. As of December 31, 2023, there were 72,337 shares available for future grants under the 2020 Plan. The 2020 Plan replaced all prior equity award plans and such plans have been discontinued. However, the awards outstanding under the prior equity award plans will continue to remain in effect in accordance with their terms. Awards that are forfeited under these prior plans upon cancellation, termination or expiration will not be available for grant under the 2020 Plan. As of December 31, 2023, a total of 655,341 shares of common stock were reserved for issuance related to the remaining outstanding equity awards granted under the prior plans. 2022 Inducement Plan On January 25, 2022, the Board of Directors approved the adoption of our 2022 Inducement Plan (the “2022 Inducement Plan”). The 2022 Inducement Plan was recommended for approval by the Compensation Committee of the Board (the “Compensation Committee”), and subsequently approved and adopted by the Board of Directors without stockholder approval pursuant to Rule 5635(c)(4) of the rules and regulations of The Nasdaq Stock Market, LLC (the “Nasdaq Listing Rules”). 310,000 shares of our common stock were reserved for issuance pursuant to equity awards that may be granted under the 2022 Inducement Plan, and the 2022 Inducement Plan will be administered by the Compensation Committee. In accordance with Rule 5635(c)(4) of the Nasdaq Listing Rules, equity awards under the 2022 Inducement Plan may only be made to an employee who has not previously been an employee or member of the Board of Directors, or following a bona fide period of non-employment by us, if he or she is granted such equity awards in connection with his or her commencement of employment with us and such grant is an inducement material to his or her entering into employment with us. As of December 31, 2023, a total of 26,650 shares were available for issuance under the 2022 Inducement Plan. Employee Stock Purchase Plan In November 2020, stockholders approved the Liquidia Corporation 2020 Employee Stock Purchase Plan (the “ESPP”). The number of shares of our common stock available for issuance under the ESPP will automatically increase on January 1 of each year through 2030, by the lesser of (a) 1.0% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, (b) 150,000 shares, or (c) an amount determined by the Board of Directors. On January 1, 2024, the number of shares of common stock available for issuance under the ESPP increased by 150,000 shares. As of December 31, 2023, a total of 707,137 shares of common stock are reserved for issuance under the ESPP. The ESPP allows eligible employees to purchase shares of our common stock at a discount through payroll deductions, subject to plan limitations. Unless otherwise determined by the administrator, the common stock will be purchased for the accounts of employees participating in the ESPP at a price per share that is 85% of the lesser of the fair market value of our common stock on the first and last trading day of the offering period. During the years ended December 31, 2023 and 2022, 140,922 and 51,941 shares were issued under the ESPP, respectively. CEO Options During December 2020, we issued a stock option grant to our then new Chief Executive Officer, Damian deGoa, to purchase up to 2,000,000 shares of our common stock (the “CEO Option”) at an exercise price of $3.00 per share. The CEO Option was issued outside of the 2020 Plan and 1,375,000 options vested in the fourth quarter of 2021 upon the achievement of certain milestones and the passage of time and ceased vesting upon the termination of Mr. deGoa’s employment on January 31, 2022. However, the CEO Option will remain exercisable so long as Mr. deGoa remains a member of our Board of Directors in accordance with his Separation Agreement. This change to vesting terms was treated as a modification of the original award resulting in a stock-based compensation charge of $2.9 million during the year ended December 31, 2022. Stock-Based Compensation Valuation and Expense We account for employee stock-based compensation plans using the fair value method. The fair value method requires us to estimate the grant-date fair value of 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 our 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. Total stock-based compensation expense recognized for employees and non-employees was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ By Expense Category: 2023 2022 ​ Research and development ​ $ 2,294 ​ $ 1,409 ​ General and administrative ​ 7,795 ​ 7,889 ​ Total stock-based compensation expense ​ $ 10,089 ​ $ 9,298 ​ ​ 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 December 31, 2023 ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Remaining ​ ​ ​ ​ ​ Recognition ​ Unamortized Period ​ ​ Expense ​ (Years) Stock options ​ $ 15,395 2.2 Restricted stock units ​ $ 8,347 ​ 2.9 ​ Fair Value of Stock Options Granted and Purchase Rights Issued under the ESPP We use the Black-Scholes option-pricing model to determine the fair value of stock options granted and purchase rights issued under the ESPP. The following table summarizes the assumptions used for estimating the fair value of stock options granted under the Black-Scholes option-pricing model: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ 2023 2022 Expected dividend yield ​ — ​ — Risk-free interest rate 3.46% - 4.73% 1.46% - 3.96% Expected volatility 90% - 95% 90% - 95% Expected life (years) 5.8 - 6.1 5.8 - 6.1 ​ The following table summarizes the assumptions used for estimating the fair value of purchase rights granted to employees under the ESPP under the Black-Scholes option-pricing model: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ 2023 2022 Expected dividend yield ​ — ​ — Risk-free interest rate ​ 5.20% - 5.47% ​ 0.69% - 3.92% Expected volatility ​ 60% - 64% ​ 80% - 129% Expected life (years) ​ 0.50 ​ 0.50 ​ The following describes our methodology for determining each assumption: Expected Dividend Yield: The dividend yield percentage is zero because we have not historically paid dividends and do not expect to for the foreseeable future. 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 our common stock during the period for which it has traded since the initial public offering. For purposes of identifying peer companies, we 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. Our 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, we estimate the expected term by using the simplified method. Stock Options The following table summarizes stock option activity during the year ended December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ ​ ​ ​ ​ ​ Average ​ Contractual ​ Aggregate ​ ​ Number of ​ Exercise ​ Term ​ Intrinsic ​ ​ Shares ​ Price ​ (in years) ​ Value Outstanding as of December 31, 2022 8,398,262 ​ $ 4.49 ​ Granted 1,463,846 ​ ​ 6.57 ​ Exercised (137,576) ​ ​ 3.59 ​ Cancelled (150,595) ​ ​ 5.60 ​ Outstanding as of December 31, 2023 9,573,937 ​ $ 4.80 7.8 ​ $ 69,440 Exercisable as of December 31, 2023 5,688,548 ​ $ 4.44 7.3 ​ $ 43,433 Vested and expected to vest as of December 31, 2023 8,974,357 ​ $ 4.75 7.7 ​ $ 65,561 ​ The weighted average fair value for options granted during the years ended December 31, 2023 and 2022 was $5.09 and $3.94 per share, respectively. The aggregate intrinsic value of stock options in the table above represents the difference between the $12.03 closing price of our common stock as of December 31, 2023 and the exercise price of outstanding, exercisable, and vested and expected to vest in-the-money stock options. Additional information related to our stock options is summarized below: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Cash proceeds from options exercised ​ $ 495 ​ $ 837 Aggregate intrinsic value of options exercised ​ $ 468 ​ $ 553 Fair value of options vested ​ $ 10,143 ​ $ 4,427 ​ Restricted Stock Units Restricted Stock Units (“RSUs”) represent the right to receive shares of our common stock at the end of a specified time period or upon the achievement of a specific milestone. RSUs can only be settled in shares of our common stock. RSUs generally vest over a four-year period similar to stock options granted to employees. The tax withholding method used for most RSUs is the sell-to-cover method, in which shares with a market value equivalent to the tax withholding obligation are sold on behalf of the holder of the RSUs upon vesting and settlement to cover the tax withholding liability and the cash proceeds from such sales are remitted to taxing authorities by us. In circumstances where the sell-to-cover method is not used, the holder of the RSUs is required to remit cash to us to cover the tax withholding liability and the cash is then remitted to taxing authorities by us. The following table summarizes our RSU activity during the year ended December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date ​ ​ Number of ​ Fair Value ​ ​ RSUs ​ (per RSU) Unvested as of December 31, 2022 407,726 ​ $ 5.57 Granted 1,508,166 ​ 6.50 Vested (201,880) ​ 5.41 Forfeited (56,034) ​ 6.22 Unvested as of December 31, 2023 1,657,978 ​ $ 6.41 ​

Revenue From Contracts With Cus

Revenue From Contracts With Customers	12 Months Ended
	Dec. 31, 2023
Revenue From Contracts With Customers
Revenue From Contracts With Customers	9. Revenue From Contracts With Customers In August 2018, we entered into a Promotion Agreement with Sandoz under which we have the exclusive rights to conduct commercial activities to encourage the appropriate use of Treprostinil Injection for the treatment of patients with PAH in the United States. We paid Sandoz $20 million at the inception of the Promotion Agreement in consideration for these rights. In exchange for conducting these commercial activities, we are entitled to receive a share of Net Profits (as defined within the Promotion Agreement) based on specified profit levels. The share of Net Profits received is subject to adjustments from Sandoz for certain items, such as distributor chargebacks, rebates, inventory returns, inventory write-offs and other adjustments. We expect to refund certain amounts to Sandoz through a reduction of the cash received from future Net Profits generated under the Promotion Agreement. As of December 31, 2023 and 2022, a $0.5 million refund liability is offset against accounts receivable from Sandoz related to expected refund amounts. Approximately 99% and 98% of revenue during the years ended December 31, 2023 and 2022, respectively, was generated from the Promotion Agreement.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Taxes
Income Taxes	10. Income Taxes No provision for federal and state income tax expense has been recorded for the years ended December 31, 2023 and 2022 due to the valuation allowance recorded against the net deferred tax asset and recurring losses. Deferred income taxes reflect the net tax effect of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of our deferred tax assets and liabilities are as follows as of December 31, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 Deferred income tax assets: ​ ​ ​ Tax loss carryforwards ​ $ 66,956 ​ $ 59,241 Research and development credits ​ 3,942 ​ 3,942 R&D section 174 costs ​ ​ 9,446 ​ ​ 4,584 Share-based compensation ​ 1,520 ​ 4,637 Lease liability ​ 863 ​ 1,157 Compensation ​ 1,982 ​ 621 Fixed assets ​ 404 ​ 369 Patent amortization ​ 396 ​ 476 Accrued litigation costs ​ ​ 1,652 ​ ​ 1,546 Settlement reserve ​ ​ 130 ​ ​ 123 Licensing agreement ​ ​ 2,367 ​ ​ — OID Interest ​ ​ 383 ​ ​ — Other ​ 21 ​ 2 Valuation allowance ​ (87,963) ​ (74,549) Total deferred income tax assets ​ 2,099 ​ 2,149 Deferred income tax liabilities: ​ ​ ​ Section 481(a) adjustment ​ — ​ 21 Intangible assets ​ 1,652 ​ 1,546 Right of use asset ​ 447 ​ 582 Total deferred income tax liabilities ​ 2,099 ​ 2,149 Total net deferred tax ​ $ — ​ $ — ​ As of December 31, 2023 and 2022, we established a full valuation allowance against our net deferred tax assets since, at the time, we could not assert that it was more likely than not that our deferred tax assets would be realized. As a result, there was an increase in the valuation allowance in 2023 of approximately $13.4 million. As of December 31, 2023, we had federal and state income tax loss carryforwards of $308.6 million and $324.6 million, respectively, which begin to expire in 2024 for both federal and state purposes. In addition, we have tax credit carryforwards for federal tax purposes of approximately $4.3 million as of December 31, 2023, which begin to expire in 2026. The utilization of net operating loss and tax credit carryforwards to reduce future income taxes will depend on our ability to generate sufficient taxable income prior to the expiration of the loss carryforwards. The Internal Revenue Code of 1986, as amended, contains provisions which limit the ability to utilize the net operating loss carryforwards in the case of certain events, including significant changes in ownership interests. If our net operating loss carryforwards are limited, and we have taxable income which exceeds the permissible yearly net operating loss carryforwards, we would incur a federal income tax liability even though net operating loss carryforwards would be available in future years. The reasons for the difference between actual income tax expense for the years ended December 31, 2023 and 2022 and the amount computed by applying the statutory federal income tax rate to income before income tax are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 ​ ​ ​ ​ ​ % of ​ ​ ​ ​ % of ​ ​ ​ ​ ​ Pretax ​ ​ ​ ​ Pretax ​ Amount Earnings Amount Earnings Income tax benefit at statutory rate ​ $ (16,486) ​ 21.0 % $ (8,613) ​ 21.0 % State income taxes, net of federal tax benefit ​ (2,553) ​ 3.3 ​ (1,787) ​ 4.4 ​ Non-deductible expenses ​ 493 ​ — ​ 1 ​ — ​ Stock-based compensation ​ 2,015 ​ (2.6) ​ 310 ​ (0.8) ​ Credits ​ — ​ — ​ — ​ — ​ Deferred tax true-up ​ ​ 2,823 ​ (3.6) ​ ​ 1,159 ​ (2.9) ​ Change in state rate ​ 260 ​ (0.3) ​ 1,368 ​ (3.3) ​ Other ​ 34 ​ — ​ — ​ — ​ Change in valuation allowance ​ 13,414 ​ (17.8) ​ 7,562 ​ (18.4) ​ Provision for income taxes ​ $ — — % $ — — % ​ We have determined that there may be a future limitation on our ability to utilize its entire federal R&D credit carryover. Therefore, we recognized an uncertain tax benefit associated with the federal R&D credit carryover during the years ended December 31, 2023 and 2022, as follows: ​ ​ ​ ​ ​ Balance at December 31, 2021 $ 455 Increases related to 2022 ​ (65) Balance at December 31, 2022 ​ 390 Decreases related to 2023 ​ — Balance at December 31, 2023 ​ $ 390 ​ We recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities based on the technical merits of the position. We have determined that it had no other material uncertain tax benefits for the year ended December 31, 2023. Our policy for recording interest and penalties related to uncertain tax provisions is to record them as a component of the provision for income taxes. We did not have any accrued interest or penalties associated with any unrecognized tax positions as of December 31, 2023 and 2022, and there were no such interest or penalties recognized during the years ended December 31, 2023 and 2022. On November 18, 2021, North Carolina enacted the 2021 Appropriations Act, which included a gradual corporate income tax rate decrease from the current 2.5% to 0% by 2030. We are in a cumulative loss position and do not have significant deferred tax liabilities that can be utilized as a source of taxable income in the future. Therefore, in 2021, we reduced our deferred tax asset related to North Carolina NOLs to zero, as no benefit is expected to be realized from these deferred tax assets prior to 2030 when there would be no income tax in North Carolina. The reduction in the value of the deferred tax assets resulted in $5.7 million of cumulative tax expense, which is fully offset by the reduction in the corresponding valuation allowance. If we become profitable prior to 2030, we will recognize an income tax benefit related to the portion of its deferred tax asset related to North Carolina NOLs utilized. We have all tax years open to examination by federal tax and state tax jurisdictions. No income tax returns are currently under examination by taxing authorities.

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Leases
Leases	11. Leases Operating Leases We are party to a non-cancelable operating lease for our laboratory and office space in Morrisville, North Carolina. The lease expires on October 31, 2026 with an option to extend for an additional period of five years with appropriate notice. We have not included the optional extension period in the measurement of lease liabilities because it is not reasonably certain that we will exercise the option to extend. The payments under this lease are subject to escalation clauses. Operating lease cost is allocated between research and development and general and administrative expenses based on the usage of the leased facilities. 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. Finance Leases We lease specialized laboratory equipment under finance leases. We do not have access to certain inputs used by our lessors to calculate the rate implicit in our finance leases and, as such, use our estimated incremental borrowing rate at the time of lease inception for the discount rate applied to our finance leases. The incremental borrowing rate used on finance leases was 6.5%. Certain finance leases also include options to purchase the leased property. We recognize all such purchase options as part of our right-of-use assets and lease liabilities if we are reasonably certain that such purchase options will be exercised. Lease Balances, Costs, and Future Minimum Payments Leases with an initial term of 12 months or less are not recorded on the balance sheet. As of December 31, 2023, we have not entered into any short-term leases. For lease agreements entered into or reassessed after the adoption of ASC 842 Leases, we combine lease and non-lease components, if any. Our lease agreements do not contain any material residual value guarantees or material restrictive covenants. Our lease cost is reflected in the accompanying statements of operations and comprehensive loss as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ Classification 2023 2022 Operating lease cost: ​ ​ ​ ​ ​ ​ ​ Fixed lease cost Research and development ​ $ 702 ​ $ 702 Fixed lease cost General and administrative ​ ​ 78 ​ ​ 78 Finance lease cost: ​ ​ ​ ​ Amortization of lease assets Research and development ​ 96 ​ 135 Interest on lease liabilities Interest expense ​ 15 ​ 32 Total Lease Cost ​ ​ ​ $ 891 ​ $ 947 ​ The weighted average remaining lease term and discount rates as of December 31, 2023 were as follows: ​ ​ ​ ​ ​ Weighted average remaining lease term (years): ​ ​ Operating leases 2.8 ​ Finance leases 1.3 ​ Weighted average discount rate: ​ Operating leases 10.3 % Finance leases 6.5 % ​ The discount rate for leases was estimated based upon market rates of collateralized loan obligations of comparable companies on comparable terms at the time of lease inception. The future minimum lease payments as of December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ Year ending December 31: ​ Leases ​ Leases ​ Total 2024 ​ $ 1,317 ​ $ 115 ​ $ 1,432 2025 ​ 1,356 ​ 64 ​ 1,420 2026 ​ 1,158 ​ — ​ 1,158 Total minimum lease payments ​ 3,831 ​ 179 ​ 4,010 Less: interest ​ (499) ​ (8) ​ (507) Present value of lease liabilities ​ $ 3,332 ​ $ 171 ​ $ 3,503 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Revenue Interest Financing Paya

Revenue Interest Financing Payable	12 Months Ended
	Dec. 31, 2023
Revenue Interest Financing Payable
Revenue Interest Financing Payable	12. Revenue Interest Financing Payable On January 9, 2023, we entered into the RIFA with HCR and HealthCare Royalty Management, LLC, pursuant to which and subject to the terms and conditions contained therein, HCR agreed to pay us an aggregate investment amount of up to $100.0 million (the “Investment Amount”) in four tranches. On January 27, 2023, $32.5 million of the Investment Amount was funded from the first tranche, $22.2 million of which was used to satisfy our existing obligations under the A&R SVB LSA (see Note 13). On June 28, 2023 and July 27, 2023, we entered into the Second Amendment to the RIFA and Third Amendment to the RIFA, respectively, pursuant to which HCR moved $2.5 million from the fourth tranche to the second tranche such that HCR would fund a total of $10.0 million of the Investment Amount under the second tranche. $10.0 million from the second tranche was funded on July 27, 2023. On January 3, 2024, we entered into the Fourth Amendment to the RIFA pursuant to which HCR moved $25.0 million from the third tranche to the second tranche, such that the total of the second tranche totals $35.0 million under the second tranche. The additional $25.0 million from the second tranche was funded on January 4, 2024. The remaining third tranche of $10.0 million and fourth tranche of $22.5 million can be funded in the future upon the mutual agreement of both parties. As consideration for the Investment Amount and pursuant to the RIFA, we have agreed to pay HCR either (a) quarterly fixed payments and a one-time fixed payment or (b) a tiered royalty on our annual net revenue after the first commercial sale of YUTREPIA (the “Revenue Interests”) depending on whether the Third Investment Amount has been funded. We are currently required to make certain fixed quarterly payments to HCR which include an additional amount on a ratable basis to reflect the funding of additional amounts by HCR under the RIFA and a one-time fixed payment. As of December 31, 2023, we were required to pay $2.6 million during the year ended December 31, 2024, which is classified as current in our consolidated balance sheet. As a result of the Fourth Amendment, if the Third Investment Amount is not funded our quarterly fixed payment will increase to $1.0 million beginning in the second quarter of 2024 and then to $5.8 million beginning in the third quarter of 2025 through 2028. Additionally, we will be obligated to pay an incremental one-time fixed payment of $23.8 million also during the third quarter of 2025 in the event that the Third Investment Amount has not been funded by June 30, 2025. If the Third Investment Amount is funded, the applicable tiered percentage will range from 3.60% to 10.28% on the first $250 million on annual net revenue, 1.44% to 4.11% on the next $250 million in annual net revenue, and 0.36% to 1.03% on all annual net revenue in excess of $500 million. The specific royalty rate within such ranges will depend upon the total amount advanced by HCR and our achievement of a certain annual net revenue threshold for the calendar year 2025. If HCR has not received cumulative payments equaling at least 60% of the amount funded to date by December 31, 2026 or at least 100% of the amount funded to date by December 31, 2028, we will be obligated to make a cash payment to HCR immediately following each applicable date in an amount sufficient to achieve such percentage funded amounts to HCR giving full consideration of the cumulative amounts paid to HCR by us through each date. HCR’s rights to receive the Revenue Interests will terminate on the date on which HCR has received payments equal to 175% of funded portion of the Investment Amount less the aggregate amount of all payments made to HCR as of such date (the “Hard Cap”), plus an amount, if any, that HCR would need to receive to yield an internal rate of return on the funded Investment Amount equal to 18% (the “IRR True-Up Payment”), unless the RIFA is earlier terminated. If a change of control occurs or upon the occurrence of an event of default, HCR may accelerate payments due under the RIFA up to the Hard Cap, plus the IRR True-Up Payment, plus any other obligations payable under the RIFA. The RIFA contains customary affirmative and negative covenants and customary events of default and other events that would cause acceleration, including, among other things, the occurrence of certain material adverse events or the material breach of certain representations and warranties and specified covenants, in which event HCR may elect to terminate the RIFA and require us to make payments to HCR equal to the lesser of (a) the Hard Cap, plus any other obligations payable under the RIFA, or (b) the funded portion of the Investment Amount, minus payments received by HCR in respect of the Revenue Interests, plus the IRR True-Up Payment. If the FDA grants final approval to an inhaled treprostinil product therapeutically equivalent to YUTREPIA and HCR has not received 100% of the amount funded by HCR to date, then we will be required to make payments to HCR equal to 100% of the amount funded by HCR to date, minus payments received by HCR in respect of the Revenue Interests. The RIFA contains certain restrictions on our ability, among other things, to incur additional debt, grant or permit additional liens, make investments and acquisitions, dispose of assets, pay dividends and distributions, subject to certain exceptions. In addition, the RIFA contains a financial covenant that requires us to maintain cash and cash equivalents in an amount at least equal to $7.5 million during the calendar year beginning on January 1, 2024 and at least equal to $15.0 million for the remainder of the payment term after the calendar year ended December 31, 2024. As of the filing date of these consolidated financial statements, we are not aware of any breach of covenants, or the occurrence of any material adverse event, nor have we received any notice of event of default from HCR. We recorded the total funds received from HCR of $42.5 million under the terms of the RIFA as a liability. The issuance costs, consisting primarily of legal fees, totaled $0.9 million and were recorded as a deduction of the carrying amount of the liability and are being amortized under the effective interest method over the estimated period the liability will be repaid. We estimated the total amount of payments over the life of the RIFA to determine the interest expense to record to accrete the liability to the amount ultimately due. For the year ended December 31, 2023, we estimated an effective annual interest rate of approximately 17% inclusive of RIFA interest accretion and debt issuance cost amortization. Over the course of the RIFA, the effective annual interest rate is expected to be affected by changes in forecasted payments. On a quarterly basis, we will reassess the expected amount and timing of payments, recalculate the amortization and effective interest rate and adjust the accounting prospectively as needed. The following table presents the changes in the liability related to RIFA during the year ended December 31, 2023: ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2023 Balance as of January 27, 2023 closing ​ $ 32,500 Issuance costs ​ ​ (906) Second tranche funding ​ ​ 10,000 Accretion ​ ​ 5,974 Amortization of issuance costs ​ ​ 119 Payments ​ ​ (1,654) Balance as of December 31, 2023 ​ $ 46,033 Less: current portion of revenue interest financing payable ​ ​ (2,615) Long-term portion of revenue interest financing payable ​ $ 43,418 ​

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2023
Long-Term Debt
Long-Term Debt	13. Long-Term Debt Long-term debt consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, ​ ​ Maturity Date ​ 2023 ​ 2022 A&R Silicon Valley Bank term loan ​ December 1, 2025 ​ $ — ​ $ 19,879 ​ Concurrent with the closing of the RIFA on January 27, 2023 (see Note 12), we repaid the amounts due under the SVB A&R LSA (as defined below), including termination fees and the Final Payment Fee, in full. This repayment resulted in a loss on extinguishment during the year ended December 31, 2023 of $2.3 million. On January 7, 2022 (the “A&R SVB LSA Effective Date”), we entered into an Amended and Restated Loan and Security Agreement with SVB and SVB Innovation Credit Fund VIII, L.P. (“Innovation”) (the “A&R SVB LSA”) under which $20.0 million was funded on the A&R SVB LSA Effective Date. $10.5 million of the proceeds were used to satisfy our existing obligations with SVB and such obligations are considered fully repaid and terminated as of that date. We accounted for such repayment in accordance with ASC 405-20, Extinguishments of Liabilities, which resulted in a loss on extinguishment during the year ended December 31, 2022 of $1.0 million. The A&R SVB LSA was to mature on December 1, 2025, and consisted of interest-only payments equal to the greater of 7.25% and the prime rate of interest plus 4.0% of the outstanding principal amount. The SVB A&R LSA also provided for a “Final Payment Fee” of 5.0% of the aggregate original principal amount of all loans made and a payment solely to SVB of $185,000 due on the earliest of the maturity date, the repayment of the debt in full, any optional prepayment or mandatory prepayment, or the termination of the A&R SVB LSA. As an inducement to enter into the A&R SVB LSA, we issued SVB, Innovation, and Innovation Credit Fund VIII-A L.P. (“Innovation Credit”) warrants to purchase an aggregate of 250,000 shares of our common stock at an exercise price of $5.14 per share. The A&R SVB Warrants provide an option for a cashless exercise. We evaluated the features of the A&R SVB LSA and A&R SVB Warrants in accordance with ASC 480, Distinguishing Liabilities from Equity and ASC 815, Derivatives and Hedging and determined that they did not contain any features that would qualify as a derivative or embedded derivative. In addition, we determined that the A&R SVB Warrants should be classified as equity. In accordance with ASC 470, Debt, the value of the A&R SVB Warrants and A&R SVB LSA was allocated using a relative fair value allocation. The fair value of the A&R SVB Warrants was determined to be $1.3 million and included in additional paid-in-capital, of which $0.7 million was recognized as a component of the loss on extinguishment and $0.6 million as a debt discount. The remaining $19.4 million was allocated to the A&R SVB LSA. In addition, we incurred fees of less than $0.1 million, which were recorded as debt issuance costs. The debt discount and debt issuance costs were being amortized to interest expense and the Final Payment Fee was being accreted using the effective interest method over the term of the A&R SVB LSA. The estimated fair value of the SVB Warrant was calculated using the Black-Scholes Option Pricing Model based on the following inputs: ​ ​ ​ ​ Expected dividend yield ​ — Risk-free interest rate 1.76% Expected volatility 97.2% Expected life (years) 10.0 ​

Defined Contribution Retirement

Defined Contribution Retirement Plan	12 Months Ended
	Dec. 31, 2023
Defined Contribution Retirement Plan
Defined Contribution Retirement Plan	14. Defined Contribution Retirement Plan We maintain a defined contribution 401(k) retirement plan for our employees, pursuant to which employees may elect to contribute a portion of their compensation on a tax-deferred basis. We match 100% of eligible employee contributions up to 4% of an employee’s salary, subject to the maximum amount permitted by the Internal Revenue Code. Our matching contributions were $0.7 million and $0.4 million for the years ended December 31, 2023 and 2022, respectively.

Legal Proceedings

Legal Proceedings	12 Months Ended
	Dec. 31, 2023
Legal Proceedings
Legal Proceedings	15. Legal Proceedings YUTREPIA-Related Litigation In June 2020, United Therapeutics filed a complaint for patent infringement against the Company in the U.S. District Court for the District of Delaware (Case No. 1:20 cv 00755 RGA) (the “Original Hatch-Waxman Litigation”), asserting infringement by the Company of U.S. Patent Nos. 9,604,901, entitled “Process to Prepare Treprostinil, the Active Ingredient in Remodulin®” (the “‘901 Patent”), and 9,593,066, entitled “Process to Prepare Treprostinil, the Active Ingredient in Remodulin®” (the “‘066 Patent”), relating to United Therapeutics’ Tyvaso®, a nebulized treprostinil solution for the treatment of PAH. United Therapeutics’ complaint was in response to the Company’s NDA for YUTREPIA, filed with the FDA, requesting approval to market YUTREPIA, a dry powder formulation of treprostinil for the treatment of PAH. The YUTREPIA NDA was filed under the 505(b)(2) regulatory pathway with Tyvaso® as the reference listed drug. In July 2020, the U.S. Patent and Trademark Office (the “USPTO”) issued U.S. Patent No. 10,716,793 (the “‘793 Patent”), entitled “Treprostinil Administration by Inhalation”, to United Therapeutics. In July 2020, United Therapeutics filed an amended complaint in the Original Hatch-Waxman Litigation asserting infringement of the ‘793 Patent by the practice of YUTREPIA. In June 2021, the Court held a claim construction hearing. Based on the Court’s construction of the claim terms, United Therapeutics filed a stipulation of partial judgment with respect to the ‘901 Patent in December 2021 under which United Therapeutics agreed to the entry of judgment of the Company’s non-infringement of the ’901 Patent. United Therapeutics did not file an appeal with respect to the ‘901 Patent. Trial proceedings in the Original Hatch-Waxman Litigation were held in March 2022. In August 2022, Judge Andrews, who was presiding over the Original Hatch-Waxman Litigation, issued an opinion that claims 1, 2, 3, 6 and 9 of the ‘066 Patent were invalid, that the remaining asserted claims of the ‘066 Patent were not infringed by the Company, and that all of the asserted claims of the ‘793 Patent were both valid and infringed by the Company, based on the arguments presented by the Company in the Original Hatch-Waxman Litigation. In September 2022, Judge Andrews entered a final judgment in the Original Hatch-Waxman Litigation that incorporated the findings from his opinion and ordered that the effective date of any final approval by the FDA of YUTREPIA shall be a date which is not earlier than the expiration date of the ’793 Patent, which will be in 2027. Both the Company and United Therapeutics appealed Judge Andrews’ decision to the United States Court of Appeals for the Federal Circuit. On July 24, 2023, the United States Court of Appeals for the Federal Circuit affirmed Judge Andrews’ decision with respect to both the ‘066 patent and the ‘793 patent. In March 2020, the Company filed two petitions for inter partes review with the Patent Trial and Appeal Board (the “PTAB”) of the USPTO. One petition was for inter partes review of the ‘901 Patent, and sought a determination that the claims in the ‘901 Patent are invalid, and a second petition was for inter partes review of the ‘066 Patent, and sought a determination that the claims in the ‘066 Patent are invalid. In October 2020, the PTAB instituted an inter partes review of the ‘901 Patent and concurrently denied institution on the ‘066 Patent, stating that the ‘066 petition has not established a reasonable likelihood that it would prevail in showing that at least one of the challenged claims is unpatentable. In October 2021, the PTAB issued a final written decision concluding that seven of the claims in the ‘901 patent were unpatentable, leaving only the narrower dependent claims 6 and 7, both of which require actual storage at ambient temperature of treprostinil sodium. In November 2021, United Therapeutics submitted a rehearing request with respect to the PTAB’s decision in the inter partes review of the ‘901 Patent. The rehearing request was denied in June 2022. In August 2022, United Therapeutics appealed the decision of the PTAB with respect to the ‘901 Patent to the United States Court of Appeals for the Federal Circuit. Oral argument was held in February 2024, and the appeal remains pending. In January 2021, the Company filed a petition for inter partes review with the PTAB relating to the ‘793 Patent, seeking a determination that the claims in the ‘793 Patent are invalid. In August 2021, the PTAB instituted an inter partes review of the ‘793 Patent, finding that the Company had demonstrated a reasonable likelihood that it would prevail with respect to showing that at least one challenged claim of the ‘793 patent is unpatentable as obvious over the combination of certain prior art cited by the Company in its petition to the PTAB. In July 2022, the PTAB ruled in the Company’s favor, concluding that based on the preponderance of the evidence, all the claims of the ’793 Patent have been shown to be unpatentable. In August 2022, United Therapeutics submitted a rehearing request with respect to the PTAB’s decision in the inter partes review of the ‘793 Patent. The rehearing request was denied in February 2023. In April 2023, United Therapeutics appealed the decision of the PTAB with respect to the ‘793 Patent to the United States Court of Appeals for the Federal Circuit. In December 2023, the United States Court of Appeals for the Federal Circuit affirmed the earlier decision by the PTAB, which found all claims of the ‘793 Patent to be unpatentable due to the existence of prior art cited by us in inter partes review proceedings. As a result of this decision by the United States Court of Appeals for the Federal Circuit, in December 2023, we filed a motion for Judge Andrews to set aside the injunction he issued in the Original Hatch-Waxman Litigation. The motion has been fully briefed and remains pending. In January 2024, United Therapeutics filed a request for rehearing of the decision by the United States Court of Appeals for the Federal Circuit. The request for rehearing was denied on March 12, 2024. United Therapeutics has the right to file a petition for a writ of certiorari to seek an appeal with the United States Supreme Court, but no such petition has been filed to date. In September 2023, United Therapeutics filed a second complaint for patent infringement against the Company in the U.S. District Court for the District of Delaware (Case No. 1:23-cv-00975-RGA) (the “New Hatch-Waxman Litigation”), again asserting infringement by the Company of the ‘793 Patent. United Therapeutics’ new complaint was in response to the Company’s amended NDA for YUTREPIA, filed with the FDA in July 2023, requesting approval to add PH-ILD to the label for YUTREPIA. In the event the decision of the PTAB invalidating the ‘793 Patent is affirmed on appeal, then such ruling would have precedential effect in the New Hatch-Waxman Litigation. In connection with an amendment to our NDA filed in July 2023 to add PH-ILD as an indication for YUTREPIA, we provided a new notice of the paragraph IV certification to United Therapeutics as the owner of the patents that are the subject of the certification to which the NDA for YUTREPIA refers. As a result, in September 2023, United Therapeutics filed a second complaint for patent infringement against us in the U.S. District Court for the District of Delaware (Case No. 1:23-cv-00975-RGA) (the “New Hatch-Waxman Litigation”), again asserting infringement by the Company of the ‘793 Patent. In November 2023, the U.S. Patent and Trademark Office (the USPTO) issued U.S. Patent No. 11,826,327, or the ‘327 Patent, entitled “Treatment for Interstitial Lung Disease”, to United Therapeutics. On November 30, 2023, United Therapeutics filed an amended complaint in the New Hatch-Waxman Litigation asserting infringement of the ‘327 Patent by the practice of YUTREPIA based on the amended NDA. In January 2024, we filed an answer, counterclaims and a partial motion to dismiss the claims related to the ‘793 Patent as a result of the decision by the United States Court of Appeals for the Federal Circuit to affirm the PTAB’s finding that the ’793 patent is unpatentable. In February 2024, United Therapeutics stipulated to the dismissal of the claims in the New Hatch-Waxman Litigation related to the ‘793 Patent. In February 2024, United Therapeutics also filed a motion seeking a preliminary injunction to prevent us from manufacturing, marketing, storing, importing, distributing, offering for sale, and/or selling YUTREPIA for the treatment of PH-ILD. Briefing on the motion for preliminary injunction is ongoing, and the motion remains pending. FDA Litigation In February 2024, United Therapeutics filed a complaint against the FDA in the U.S. District Court for the District of Columbia, challenging the FDA’s acceptance of our amended NDA for review (the “FDA Litigation”). On March 4, 2024, United Therapeutics filed a motion for a temporary restraining order in the FDA Litigation, seeking to enjoin the FDA from approving our NDA for YUTREPIA with respect to the indication to treat PH-ILD. Briefing on the motion for a temporary restraining order is ongoing, and the motion remains pending. Trade Secret Litigation In December 2021, United Therapeutics filed a complaint in the Superior Court in Durham County, North Carolina, alleging that the Company and a former United Therapeutics employee, who later joined the Company as an employee many years after terminating his employment with United Therapeutics, conspired to misappropriate certain trade secrets of United Therapeutics and engaged in unfair or deceptive trade practices. In January 2024, our co-defendant in the lawsuit filed a motion to dismiss all claims. The motion is being briefed and remains pending. Fact discovery in the case has concluded, and expert discovery is in process. RareGen Litigation In April 2019, Sandoz and Liquidia PAH (then known as RareGen) filed a complaint against United Therapeutics and Smiths Medical in the District Court of New Jersey (Case No. No. 3:19 cv 10170), (the “RareGen Litigation”), alleging that United Therapeutics and Smiths Medical violated the Sherman Antitrust Act of 1890, state law antitrust statutes and unfair competition statutes by engaging in anticompetitive acts regarding the drug treprostinil for the treatment of PAH. In March 2020, Sandoz and Liquidia PAH filed a first amended complaint adding a claim that United Therapeutics breached a settlement agreement that was entered into in 2015, in which United Therapeutics agreed to not interfere with Sandoz’s efforts to launch its generic treprostinil, by taking calculated steps to restrict and interfere with the launch of Sandoz’s competing generic product. United Therapeutics developed treprostinil under the brand name Remodulin® and Smiths Medical manufactured a pump and cartridges that are used to inject treprostinil into patients continuously throughout the day. Sandoz and Liquidia PAH allege that United Therapeutics and Smiths Medical entered into anticompetitive agreements (i) whereby Smiths Medical placed restrictions on the cartridges such that they can only be used with United Therapeutics’ branded Remodulin® product and (ii) requiring Smiths Medical to enter into agreements with specialty pharmacies to sell the cartridges only for use with Remodulin®. In November 2020, Sandoz and Liquidia PAH entered into a binding term sheet (the “Term Sheet”) with Smiths Medical in order to resolve the outstanding RareGen Litigation solely with respect to disputes between Smiths Medical, Liquidia PAH and Sandoz. In April 2021, Liquidia PAH and Sandoz entered into a Long Form Settlement Agreement (the “Settlement Agreement”) with Smiths Medical to further detail the terms of the settlement among such parties as reflected in the Term Sheet. Pursuant to the Term Sheet and the Settlement Agreement, the former RareGen members and Sandoz received a payment of $4.25 million that was evenly split between the parties. In addition, pursuant to the Term Sheet and Settlement Agreement, Smiths Medical disclosed and made available to Sandoz and Liquidia PAH certain specifications and other information related to the cartridge that Smiths Medical developed and manufactures for use with the CADD-MS 3 infusion pump (the “CADD-MS 3 Cartridge”). Pursuant to the Settlement Agreement, Smiths Medical also granted Liquidia PAH and Sandoz a non-exclusive, royalty-free license in the United States to Smiths Medical’s patents and copyrights associated with the CADD-MS 3 Cartridge and certain other information for use of the CADD-MS 3 pump and the CADD-MS 3 Cartridges. Smiths also agreed in the Settlement Agreement to provide information and assistance in support of Liquidia PAH’s efforts to receive FDA clearance for the RG 3ml Medication Cartridge (the “RG Cartridge”) and to continue to service certain CADD-MS 3 pumps that are available for use with the Treprostinil Injection through January 1, 2025. Liquidia PAH and Sandoz agreed, among other things, to indemnify Smiths from certain liabilities related to the RG Cartridge. In September 2021, United Therapeutics filed a motion for summary judgment with respect to all of the claims brought by Sandoz and Liquidia PAH against United Therapeutics. At the same time, Sandoz filed a motion for summary judgment with respect to the breach of contract claim. In March 2022, the Court issued an order granting partial summary judgment to United Therapeutics with respect to the antitrust and unfair competition claims, denying summary judgment to United Therapeutics with respect to the breach of contract claim, and granting partial summary judgment to Sandoz with respect to the breach of contract claim. The RareGen Litigation will now proceed to a trial to determine the amount of damages due from United Therapeutics to Sandoz with respect to the breach of contract claim. Trial is scheduled to start on April 29, 2024. Under the Promotion Agreement, all proceeds from the litigation will be divided evenly between Sandoz and Liquidia PAH. Under the litigation finance agreements that Liquidia PAH has entered into with Henderson and PBM, any net proceeds received by Liquidia PAH with respect to the RareGen Litigation will be divided between Henderson and PBM.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies.
Commitments and Contingencies	16. Commitments and Contingencies Pharmosa License Agreement and Asset Transfer Agreement In June 2023, we entered into a License Agreement with Pharmosa Biopharm Inc. (“Pharmosa”) pursuant to which we were granted an exclusive license in North America to develop and commercialize L606, an inhaled, sustained-release formulation of treprostinil currently being evaluated in a clinical trial for the treatment of pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD), and a non-exclusive license for the manufacture, development and use (but not commercialization) of such licensed product in most countries outside North America (the “Pharmosa License Agreement”). Under the terms of the Pharmosa License Agreement, we will be responsible for development, regulatory and commercial activities of L606 in North America. Pharmosa will manufacture clinical and commercial supplies of the liposomal formulation through its global supply chain and support us in establishing a redundant global supply chain. In consideration for these exclusive rights, we paid Pharmosa an upfront license fee of $10 million and will pay Pharmosa potential development milestone payments tied to PAH and PH-ILD indications of up to $30 million, potential sales milestones of up to $185 million and two tiers of low, double-digit royalties on net sales of L606. Pharmosa will also receive a $10 million milestone payment for each additional indication approved after PAH and PH-ILD and each additional product approved under the license. We also retain the first right to negotiate for development and commercialization of L606 in Europe and other territories should Pharmosa seek a partner, subject to satisfaction of certain conditions as set forth in the Pharmosa License Agreement. Concurrently with the execution of the Pharmosa License Agreement, we also entered into an Asset Transfer Agreement with Pharmosa pursuant to which Pharmosa will transfer its inventory of physical materials. Mainbridge Health Care Device Development and Supply Agreement In December 2022, we entered into a Device Development and Supply Agreement (the “Pump Development Agreement”) with Mainbridge Health Partners, LLC (“Mainbridge”) and Sandoz Inc. (“Sandoz”). The Pump Development Agreement provides for the cooperation between us, Sandoz and Mainbridge to develop a new pump that is suitable for the subcutaneous administration of Treprostinil Injection. Mainbridge will perform all development, validation and testing activities required for the pump and related consumables in anticipation of submitting a 510(k) clearance application for the pump to the FDA in the first half of 2024. In connection with the Pump Development Agreement, we and Sandoz have agreed to pay Mainbridge certain future contingent milestone payments in accordance with the terms and conditions set forth therein. UNC License Agreement We perform 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, we hold an exclusive license to certain research and development technologies and processes in various stages of patent pursuit, for use in our 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, we are 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, including YUTREPIA. We 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. Chasm Technologies In March 2012, we entered into an agreement, as amended, with Chasm Technologies, Inc. for manufacturing consulting services related to our manufacturing capabilities during the term of the agreement. We agreed to pay future contingent milestones and royalties on net sales totaling no more than $1.5 million, $0.2 million of which has been accrued as of December 31, 2023. Employment Agreements We have agreements with certain employees which require payments if certain events, such as a change in control or termination without cause, occur. Purchase Obligations We enter into contracts in the normal course of business with contract service providers to assist in the performance of research and development and manufacturing activities. Subject to required notice periods and obligations under binding purchase orders, we can elect to discontinue the work under these agreements at any time. On July 14, 2023, we entered into an Amended and Restated Commercial Manufacturing Services and Supply Agreement with Lonza Tampa LLC (“Lonza”) (the “CSA”). Lonza is our sole supplier for encapsulation and packaging services for YUTREPIA. Pursuant to the terms of the CSA, we deliver bulk treprostinil powder, manufactured using our proprietary PRINT® technology, and Lonza encapsulates and packages it. The CSA was effective upon signing and will be in effect for an initial term of 5 years from receipt of regulatory approval of YUTREPIA by the FDA (“Regulatory Approval”) absent termination by either party in accordance with the terms of the CSA. We may terminate the CSA upon 60 days’ written notice to Lonza in the event that the application for regulatory approval is rejected by the FDA and such FDA decision is not caused by the fault of the Company (the “Termination for FDA Rejection”). Lonza may terminate the CSA upon 120 days written notice if we do not receive regulatory approval by December 31, 2024 (the “Termination for FDA Delay”). Upon any Termination for FDA Rejection or Termination for FDA Delay, we would reimburse Lonza for 50% of its documented out-of-pocket expenditures for any capital equipment that is purchased by Lonza after the effective date of the Agreement to perform the services for us, not to exceed $2.5 million in the aggregate. We are required to provide Lonza with quarterly forecasts of our expected production requirements for the following 24-month period, the first twelve months of which is considered a binding, firm order. We are required to purchase certain minimum annual order quantities, which may be adjusted by us after the thirteenth month after receipt of regulatory approval (as defined in the CSA). The CSA provides for tiered pricing depending upon the batch size ordered. As of December 31, 2023, we have non-cancelable commitments with Lonza Tampa LLC for product manufacturing costs of approximately $4.1 million for the year ending 2024. In addition, we are party to a multi-year supply agreement with LGM Pharma, LLC (LGM) to produce active pharmaceutical ingredients for YUTREPIA. Under the supply agreement with LGM, we are required to provide rolling forecasts, a portion of which will be considered a binding, firm order, subject to an annual minimum purchase commitment of $2.7 million for the term of the agreement. As of December 31, 2023, we have incurred and paid the full annual purchase commitment of $2.7 million. The agreement expires five years from the first marketing authorization approval of YUTREPIA. Other Contingencies and Commitments From time-to-time we are subject to claims and litigation in the normal course of business, none of which do we believe represent a risk of material loss or exposure. See Note 15 for further discussion of pending legal proceedings. In addition to the commitments described above, we are party to other commitments, including non-cancelable leases and long-term debt, which are described elsewhere in these notes to the consolidated financial statements.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2023
Subsequent Events
Subsequent Events	17. Subsequent Events Fourth Amendment to Revenue Interest Financing Agreement On January 3, 2024, we entered into the Fourth Amendment to the RIFA pursuant to which HCR moved $25.0 million from the third tranche to the second tranche, such that HCR will have funded a total of $35.0 million under the second tranche. The additional $25.0 million from the second tranche was funded on January 4, 2024. The remaining third tranche of $10.0 million and fourth tranche of $22.5 million can be funded in the future upon the mutual agreement of both parties. See Note 12 for further information. Private Placement On January 4, 2024, we entered into a Common Stock Purchase Agreement with Legend Aggregator, LP, for the sale by us in a private placement (the “2024 Private Placement”) of an aggregate of 7,182,532 shares of our common stock at a purchase price of $10.442 per share. The 2024 Private Placement closed on January 8, 2024, and we received gross proceeds of approximately $75.0 million, before deducting offering costs of less than $0.1 million.

Basis of Presentation, Signif_2

Basis of Presentation, Significant Accounting Policies and Fair Value Measurements (Policies)	12 Months Ended
	Dec. 31, 2023
Basis of Presentation, Significant Accounting Policies and Fair Value Measurements
Basis of Presentation	Basis of Presentation These consolidated financial statements, 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”). Our financial position, results of operations and cash flows are presented in U.S. Dollars.
Consolidation	Consolidation The accompanying consolidated financial statements include our wholly owned subsidiaries, Liquidia Technologies and Liquidia PAH. All intercompany accounts and transactions have been eliminated.
Use of Estimates	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 to be reasonable under the circumstances. We evaluate our estimates on an ongoing basis, including those related to the valuation of stock-based awards, certain accruals, the revenue interest financing payable, and intangible and contract acquisition cost amortization, and make changes to the estimates and related disclosures as our experience develops or new information becomes known. Actual results will most likely differ from those estimates.
Segment Information	Segment Information GAAP requires segmentation based on an entity’s internal organization and reporting of revenue and operating income based upon internal accounting methods commonly referred to as the “management approach.” Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker (CODM), or decision-making group, in deciding how to allocate resources and in assessing performance. Our CODM is our Chief Executive Officer. We have determined that we have one operating and reporting segment.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Subtopic 280) . This guidance The guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal periods beginning after December 15, 2024. We are in the process of evaluating the impact of this guidance on our consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Subtopic 740) . This guidance The guidance is effective for fiscal years beginning after December 15, 2024. We are in the process of evaluating the impact of this guidance on our consolidated financial statements and related disclosures.
Cash, Cash Equivalents, and Concentration of Credit Risk	Cash, Cash Equivalents, and Concentration of Credit Risk We consider all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. Financial instruments that potentially subject us to concentrations of credit risk consist of cash and cash equivalents. We are exposed to credit risk, subject to federal deposit insurance, in the event of default by the financial institutions holding our cash and cash equivalents to the extent of amounts recorded on the consolidated balance sheet. As of December 31, 2022, all of our cash and cash equivalents were held with Silicon Valley Bank (“SVB”). Following the March 10, 2023 Federal Deposit Insurance Corporation takeover of SVB, substantially all of our cash and cash equivalents have been moved to multiple accredited financial institutions. We have not experienced any losses on such accounts and do not believe that we are subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Such deposits have exceeded and will continue to exceed federally insured limits.
Accounts Receivable	Accounts Receivable Accounts receivable are stated at net realizable value and net of an allowance for credit losses as of each balance sheet date, if applicable. As of December 31, 2023 and 2022, one customer accounted for 99% of our accounts receivable, net. As of December 31, 2023 and 2022, we have not recorded an allowance for credit losses.
Prelaunch Inventory	Prelaunch Inventory We capitalize prelaunch inventory prior to receiving regulatory approval if regulatory approval and subsequent commercialization of a product is probable and we also expect future economic benefit from the sales of the product to be realized. Prior to this, we expense prelaunch inventory as research and development expense in the period incurred. For prelaunch inventory that is capitalized, we consider a number of specific facts and circumstances, including the product’s historical shelf life, the product's current status in the development and regulatory approval process, results from related clinical trials, results from meetings with relevant regulatory agencies prior to the filing of regulatory applications, potential obstacles to the approval process, historical experience, viability of commercialization and market trends. No prelaunch inventory was capitalized as of December 31, 2023.
Leases	Leases ASC 842 Leases is expensed over the lease term on a straight-line basis, with all cash flows classified as an operating activity in the Statement of Cash Flows. For finance leases, interest on the lease liability is recognized separately from the amortization of the right-of-use asset in the Statement of Operations and Comprehensive Loss and the repayment of the principal portion of the lease liability is classified as a financing activity, while the interest component is classified as an operating activity in the Statement of Cash Flows.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost. Depreciation of property, plant and equipment is computed using the straight-line method over the estimated useful lives of the assets beginning when the assets are placed in service. Estimated useful lives for the major asset categories are: ​ ​ ​ ​ Lab and build-to-suit equipment (years) 5 - 7 Office equipment (years) ​ 5 Furniture and fixtures (years) ​ 10 Computer equipment (years) ​ 3 Leasehold improvements Lesser of life of the asset or remaining lease term ​ Major renewals and improvements are capitalized to the extent that they increase the useful economic life or increase the expected economic benefit of the underlying asset. Maintenance and repairs are charged to operations as incurred. When items of property, plant and equipment are sold or retired, the related cost and accumulated depreciation or amortization is removed from the accounts, and any gain or loss is included in operating expenses in the accompanying Statements of Operations and Comprehensive Loss.
Long-Lived Assets	Long-Lived Assets We review 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. We also review for impairment when conditions exist that indicate the carrying amount of the assets may not be fully recoverable. In those circumstances, we perform undiscounted operating cash flow analyses to determine if an impairment exists. When testing for asset impairment, we group 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	Goodwill We assess 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. For example, significant and unanticipated changes or our inability to obtain or maintain regulatory approvals for our product candidates, including the NDA for YUTREPIA, could trigger testing of our goodwill for impairment at an interim date. We have one reporting unit. We have 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 ASC 350 Intangibles-Goodwill and Other We completed our annual goodwill impairment test as of July 1, 2023. There have been no significant events or circumstances affecting the valuation of goodwill subsequent to the assessment.
Revenue Interest Financing Payable	Revenue Interest Financing Payable We recognized a liability related to amounts received in January 2023 and July 2023 pursuant to the RIFA under ASC 470-10, Debt Interest - Imputation of Interest
Revenue Recognition	Revenue Recognition We recognize revenue in accordance with ASC 606, Revenue from Contracts with Customers ● 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, we assess the promised goods or services in the contract and identify 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. We evaluate 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. We recognize 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.
Research and Development Expense	Research and Development Expense Research and development costs are expensed as incurred in accordance with ASC 730, Research and Development
Patent Maintenance	Patent Maintenance We are responsible for all patent costs, past and future, associated with the preparation, filing, prosecution, issuance, maintenance, enforcement and defense of United States patent applications to which we have rights other than those patents that we license from Pharmosa that are not specific to L606. Such costs are recorded as general and administrative expenses as incurred. To the extent that our licensees share these costs, such benefit is recorded as a reduction of the related expenses.
Stock-Based Compensation	Stock-Based Compensation We estimate the grant date fair value of stock-based awards and amortize this fair value to compensation expense over the requisite service period or the vesting period of the respective award. In arriving at stock-based compensation expense, we estimate the number of stock-based awards that will be forfeited due to employee turnover. The forfeiture assumption is based primarily on turn-over historical experience. If the actual forfeiture rate is higher than the estimated forfeiture rate, then an adjustment will be made to increase the estimated forfeiture rate, which will result in a decrease to the expense recognized in our financial statements. If the actual forfeiture rate is lower than the estimated forfeiture rate, then an adjustment will be made to lower the estimated forfeiture rate, which will result in an increase to expense recognized in our financial statements. The expense we recognize in future periods will be affected by changes in the estimated forfeiture rate and may differ from amounts recognized in the current period. See Note 8.
Net Loss Per Share	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 weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. Due to their anti-dilutive effect, the calculation of diluted net loss per share excludes the following common stock equivalent shares: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ ​ 2023 ​ 2022 Stock Options 9,513,039 7,757,017 Restricted Stock Units 1,685,532 399,349 Warrants ​ 450,000 ​ 445,205 Total 11,648,571 8,601,571 ​ Certain common stock warrants are included in the calculation of basic and diluted net loss per share since their exercise price is de minimis.
Income Taxes	Income Taxes The asset and liability method is used in our accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. We record a valuation allowance against deferred tax assets when realization of the tax benefit is uncertain. A valuation allowance is recorded, if necessary, to reduce net deferred taxes to their realizable values if management believes it is more likely than not that the net deferred tax assets will not be realized. We may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities based on the technical merits of the position. The tax benefits recognized in the financial statements from such a position are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement.
Fair Value Measurements	Fair Value Measurements ASC 825 Financial Instruments Level 1 — Quoted prices in active markets for identical assets or liabilities; Level 2 — Inputs other than quoted prices included in active markets 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 table presents the placement in the fair value hierarchy of financial assets and liabilities measured at fair value as of December 31, 2023 and December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2023 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Money market funds (cash equivalents) ​ $ 79,912 ​ $ — ​ $ — ​ $ 79,912 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2022 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Money market funds (cash equivalents) ​ $ 92,283 ​ $ — ​ $ — ​ $ 92,283 ​ Money market funds are included in cash and cash equivalents on our consolidated balance sheet and are classified within Level 1 of the fair value hierarchy since they are valued using quoted market prices. The carrying amounts reflected in our consolidated balance sheets for cash, accounts receivable, 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 carrying value of long-term debt and the revenue interest financing payable approximate fair value as the respective interest rates are reflective of current market rates on debt with similar terms and conditions. In addition, the revenue interest financing payable is updated with the expected amount to be paid back each reporting period based on the contractual terms and current projections.

Basis of Presentation, Signif_3

Basis of Presentation, Significant Accounting Policies and Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Basis of Presentation, Significant Accounting Policies and Fair Value Measurements
Schedule of property, plant and equipment, useful life	​ ​ ​ ​ Lab and build-to-suit equipment (years) 5 - 7 Office equipment (years) ​ 5 Furniture and fixtures (years) ​ 10 Computer equipment (years) ​ 3 Leasehold improvements Lesser of life of the asset or remaining lease term
Summary of calculation of diluted net loss per share	​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ ​ 2023 ​ 2022 Stock Options 9,513,039 7,757,017 Restricted Stock Units 1,685,532 399,349 Warrants ​ 450,000 ​ 445,205 Total 11,648,571 8,601,571
Summary of financial assets and liabilities measured at fair value	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2023 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Money market funds (cash equivalents) ​ $ 79,912 ​ $ — ​ $ — ​ $ 79,912 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Significant ​ ​ ​ ​ ​ ​ Prices in ​ Other ​ Significant ​ ​ ​ ​ ​ Active ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Markets ​ Inputs ​ Inputs ​ Carrying December 31, 2022 ​ (Level 1) ​ (Level 2) ​ (Level 3) ​ Value Money market funds (cash equivalents) ​ $ 92,283 ​ $ — ​ $ — ​ $ 92,283 ​

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment
Schedule of Property, plant and equipment	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, ​ ​ 2023 ​ 2022 Lab and build-to-suit equipment ​ $ 6,834 ​ $ 6,257 Office equipment ​ 19 ​ 19 Furniture and fixtures ​ 241 ​ 134 Computer equipment ​ 487 ​ 291 Leasehold improvements ​ 11,409 ​ 11,409 Construction-in-progress ​ 804 ​ 155 Total property, plant and equipment ​ 19,794 ​ 18,265 Accumulated depreciation and amortization ​ (15,314) ​ (14,114) Property, plant and equipment, net ​ $ 4,480 ​ $ 4,151

Contract Acquisition Costs an_2

Contract Acquisition Costs and Intangible Asset, and Goodwill (Tables)	12 Months Ended
	Dec. 31, 2023
Contract Acquisition Costs and Intangible Asset, and Goodwill
Schedule of contract acquisition costs and intangible asset	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 ​ ​ Gross Carrying Amount ​ Accumulated Amortization ​ Net Carrying Amount ​ Gross Carrying Amount ​ Accumulated Amortization ​ Net Carrying Amount Contract acquisition costs ​ $ 12,980 ​ $ (5,058) ​ $ 7,922 ​ $ 12,980 ​ $ (4,376) ​ $ 8,604 Intangible asset ​ $ 5,620 ​ $ (2,190) ​ $ 3,430 ​ $ 5,620 ​ $ (1,894) ​ $ 3,726

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2023
Accrued Expenses and Other Current Liabilities
Schedule of Accrued expenses and other current liabilities	Accrued expenses and other current liabilities consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2023 2022 Accrued compensation ​ $ 8,544 ​ $ 2,862 Accrued research and development expenses ​ ​ 2,902 ​ ​ 1,757 Accrued other expenses ​ ​ 1,954 ​ ​ 903 Total accrued expenses and other current liabilities ​ $ 13,400 ​ $ 5,522 ​

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity
Schedule of outstanding warrants	Outstanding warrants consisted of the following as of December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ ​ ​ ​ ​ ​ warrants Exercise Price Expiration Date A&R SVB Warrant (see Note 13) ​ 250,000 ​ $ 5.14 ​ January 6, 2032 SVB Warrant - Initial Tranche (see Note 13) ​ 100,000 ​ $ 3.05 ​ February 26, 2031 SVB Warrant - Term B and Term C Tranches (see Note 13) ​ 100,000 ​ $ n/a ​ February 26, 2031 Other warrants ​ 65,572 ​ $ 0.02 ​ December 31, 2026 ​

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Schedule of stock-based compensation expense recognized for employees and non-employees	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ By Expense Category: 2023 2022 ​ Research and development ​ $ 2,294 ​ $ 1,409 ​ General and administrative ​ 7,795 ​ 7,889 ​ Total stock-based compensation expense ​ $ 10,089 ​ $ 9,298 ​
Schedule of unamortized compensation expense and weighted average remaining recognition period	​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2023 ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Remaining ​ ​ ​ ​ ​ Recognition ​ Unamortized Period ​ ​ Expense ​ (Years) Stock options ​ $ 15,395 2.2 Restricted stock units ​ $ 8,347 ​ 2.9
Schedule of assumptions used for estimating the fair value of stock options	​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ 2023 2022 Expected dividend yield ​ — ​ — Risk-free interest rate 3.46% - 4.73% 1.46% - 3.96% Expected volatility 90% - 95% 90% - 95% Expected life (years) 5.8 - 6.1 5.8 - 6.1 ​
Schedule of non vested RSU awards outstanding	​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date ​ ​ Number of ​ Fair Value ​ ​ RSUs ​ (per RSU) Unvested as of December 31, 2022 407,726 ​ $ 5.57 Granted 1,508,166 ​ 6.50 Vested (201,880) ​ 5.41 Forfeited (56,034) ​ 6.22 Unvested as of December 31, 2023 1,657,978 ​ $ 6.41 ​
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ ​ ​ ​ ​ ​ Average ​ Contractual ​ Aggregate ​ ​ Number of ​ Exercise ​ Term ​ Intrinsic ​ ​ Shares ​ Price ​ (in years) ​ Value Outstanding as of December 31, 2022 8,398,262 ​ $ 4.49 ​ Granted 1,463,846 ​ ​ 6.57 ​ Exercised (137,576) ​ ​ 3.59 ​ Cancelled (150,595) ​ ​ 5.60 ​ Outstanding as of December 31, 2023 9,573,937 ​ $ 4.80 7.8 ​ $ 69,440 Exercisable as of December 31, 2023 5,688,548 ​ $ 4.44 7.3 ​ $ 43,433 Vested and expected to vest as of December 31, 2023 8,974,357 ​ $ 4.75 7.7 ​ $ 65,561
Schedule of additional information related to stock options	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2023 2022 Cash proceeds from options exercised ​ $ 495 ​ $ 837 Aggregate intrinsic value of options exercised ​ $ 468 ​ $ 553 Fair value of options vested ​ $ 10,143 ​ $ 4,427
Employee Stock Purchase Plan
Schedule of assumptions used for estimating the fair value of stock options	​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ 2023 2022 Expected dividend yield ​ — ​ — Risk-free interest rate ​ 5.20% - 5.47% ​ 0.69% - 3.92% Expected volatility ​ 60% - 64% ​ 80% - 129% Expected life (years) ​ 0.50 ​ 0.50

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Taxes
Schedule of deferred tax assets and liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 Deferred income tax assets: ​ ​ ​ Tax loss carryforwards ​ $ 66,956 ​ $ 59,241 Research and development credits ​ 3,942 ​ 3,942 R&D section 174 costs ​ ​ 9,446 ​ ​ 4,584 Share-based compensation ​ 1,520 ​ 4,637 Lease liability ​ 863 ​ 1,157 Compensation ​ 1,982 ​ 621 Fixed assets ​ 404 ​ 369 Patent amortization ​ 396 ​ 476 Accrued litigation costs ​ ​ 1,652 ​ ​ 1,546 Settlement reserve ​ ​ 130 ​ ​ 123 Licensing agreement ​ ​ 2,367 ​ ​ — OID Interest ​ ​ 383 ​ ​ — Other ​ 21 ​ 2 Valuation allowance ​ (87,963) ​ (74,549) Total deferred income tax assets ​ 2,099 ​ 2,149 Deferred income tax liabilities: ​ ​ ​ Section 481(a) adjustment ​ — ​ 21 Intangible assets ​ 1,652 ​ 1,546 Right of use asset ​ 447 ​ 582 Total deferred income tax liabilities ​ 2,099 ​ 2,149 Total net deferred tax ​ $ — ​ $ —
Schedule of federal income tax rate	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 ​ ​ ​ ​ ​ % of ​ ​ ​ ​ % of ​ ​ ​ ​ ​ Pretax ​ ​ ​ ​ Pretax ​ Amount Earnings Amount Earnings Income tax benefit at statutory rate ​ $ (16,486) ​ 21.0 % $ (8,613) ​ 21.0 % State income taxes, net of federal tax benefit ​ (2,553) ​ 3.3 ​ (1,787) ​ 4.4 ​ Non-deductible expenses ​ 493 ​ — ​ 1 ​ — ​ Stock-based compensation ​ 2,015 ​ (2.6) ​ 310 ​ (0.8) ​ Credits ​ — ​ — ​ — ​ — ​ Deferred tax true-up ​ ​ 2,823 ​ (3.6) ​ ​ 1,159 ​ (2.9) ​ Change in state rate ​ 260 ​ (0.3) ​ 1,368 ​ (3.3) ​ Other ​ 34 ​ — ​ — ​ — ​ Change in valuation allowance ​ 13,414 ​ (17.8) ​ 7,562 ​ (18.4) ​ Provision for income taxes ​ $ — — % $ — — %
Schedule of recognized uncertain tax benefit	​ ​ ​ ​ ​ Balance at December 31, 2021 $ 455 Increases related to 2022 ​ (65) Balance at December 31, 2022 ​ 390 Decreases related to 2023 ​ — Balance at December 31, 2023 ​ $ 390

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases
Schedule of lease cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ Classification 2023 2022 Operating lease cost: ​ ​ ​ ​ ​ ​ ​ Fixed lease cost Research and development ​ $ 702 ​ $ 702 Fixed lease cost General and administrative ​ ​ 78 ​ ​ 78 Finance lease cost: ​ ​ ​ ​ Amortization of lease assets Research and development ​ 96 ​ 135 Interest on lease liabilities Interest expense ​ 15 ​ 32 Total Lease Cost ​ ​ ​ $ 891 ​ $ 947 ​ ​ ​ ​ ​ Weighted average remaining lease term (years): ​ ​ Operating leases 2.8 ​ Finance leases 1.3 ​ Weighted average discount rate: ​ Operating leases 10.3 % Finance leases 6.5 %
Schedule of lease liability maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ Year ending December 31: ​ Leases ​ Leases ​ Total 2024 ​ $ 1,317 ​ $ 115 ​ $ 1,432 2025 ​ 1,356 ​ 64 ​ 1,420 2026 ​ 1,158 ​ — ​ 1,158 Total minimum lease payments ​ 3,831 ​ 179 ​ 4,010 Less: interest ​ (499) ​ (8) ​ (507) Present value of lease liabilities ​ $ 3,332 ​ $ 171 ​ $ 3,503 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Revenue Interest Financing Pa_2

Revenue Interest Financing Payable (Tables)	12 Months Ended
	Dec. 31, 2023
Revenue Interest Financing Payable
Schedule of changes in the liability related to RIFA	​ ​ ​ ​ ​ ​ December 31, ​ ​ 2023 Balance as of January 27, 2023 closing ​ $ 32,500 Issuance costs ​ ​ (906) Second tranche funding ​ ​ 10,000 Accretion ​ ​ 5,974 Amortization of issuance costs ​ ​ 119 Payments ​ ​ (1,654) Balance as of December 31, 2023 ​ $ 46,033 Less: current portion of revenue interest financing payable ​ ​ (2,615) Long-term portion of revenue interest financing payable ​ $ 43,418 ​

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2023
Long-Term Debt
Schedule of Long-Term Debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, ​ ​ Maturity Date ​ 2023 ​ 2022 A&R Silicon Valley Bank term loan ​ December 1, 2025 ​ $ — ​ $ 19,879
SVB Warrant
Long-Term Debt
Schedule of Inputs used to Estimate Fair Value of Warrants	​ ​ ​ ​ Expected dividend yield ​ — Risk-free interest rate 1.76% Expected volatility 97.2% Expected life (years) 10.0 ​

Business - Recent Developments

Business - Recent Developments (Details) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 08, 2024	Jan. 04, 2024	Jan. 03, 2024	Jul. 27, 2023	Jul. 27, 2023	Dec. 31, 2023	Jan. 04, 2024	Jun. 30, 2023
Recent Developments
Amount funded under the second tranche						$ 10,000
Private Placement | Subsequent Events.
Recent Developments
Payments for offering costs		$ 100
Pharmosa License Agreement
Recent Developments
Upfront license fee to be paid								$ 10,000
Legend Aggregator, LP | Private Placement | Subsequent Events.
Recent Developments
Stock Issued During Period, Shares, New Issues (in shares)		7,182,532
Shares Issued, Price Per Share (in dollars per share)		$ 10.442					$ 10.442
Proceeds from Issuance of Private Placement	$ 75,000	$ 75,000
Payments for offering costs		100
Fourth Amendment to Revenue Interest Financing Agreement | Subsequent Events.
Recent Developments
Amount moved from third tranche to second tranche			$ 25,000
Amount funded under the second tranche		$ 25,000					$ 35,000
Amount to be funded under the second tranche.			35,000
Amount to be funded under third tranche			10,000
Amount to be funded under fourth tranche			22,500
Fourth Amendment to Revenue Interest Financing Agreement | HCR | Subsequent Events.
Recent Developments
Amount to be funded under third tranche			10,000
Amount to be funded under fourth tranche			$ 22,500
Second and Third Amendments to Revenue Interest Financing Agreement
Recent Developments
Amount funded under the second tranche				$ 10,000
Amount to be funded under the second tranche.					$ 10,000
Amount moved from fourth tranche to second tranche					$ 2,500

Business - Liquidity (Details)

Business - Liquidity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Business
Net loss	$ 78,502	$ 41,015
Accumulated deficit	429,098	$ 350,596
For Calendar Year Beginning on January 1 , 2024
Business
Revenue interest financing agreement	15,000
Revenue Interest Financing Agreement. | HealthCare Royalty Partners IV, L.P and HealthCare Royalty Management, LLC | For Calendar Year Beginning on January 1 , 2024
Business
Revenue interest financing agreement	$ 7,500

Basis of Presentation, Signif_4

Basis of Presentation, Significant Accounting Policies and Fair Value Measurements - Other (Details)		12 Months Ended
	Jan. 09, 2023 USD ($)	Dec. 31, 2023 USD ($) segment customer	Dec. 31, 2022 USD ($) customer
Net loss		$ 78,502,000	$ 41,015,000
Accumulated deficit		$ 429,098,000	$ 350,596,000
Number of operating segments | segment		1
Number of reporting units		1
Impairment of long-lived assets		$ 0
Inventory, Capitalized Cost		$ 0
Revenue Interest Financing Agreement.
Minimum cash and cash equivalents required to be maintained during next year	$ 7,500,000
Minimum cash and cash equivalents required to be maintained after December 31, 2024	$ 15,000,000
Credit Concentration Risk | Accounts Receivable | Customer One
Concentration risk, percentage		99%	99%
Number of customers | customer		1	1

Basis of Presentation, Signif_5

Basis of Presentation, Significant Accounting Policies and Fair Value Measurements - Estimated Useful Lives for Major Asset Categories (Details)	Dec. 31, 2023
Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]	us-gaap:UsefulLifeShorterOfTermOfLeaseOrAssetUtilityMember
Lab and build-to-suit equipment | Minimum
Property, Plant and Equipment, Useful life	5 years
Lab and build-to-suit equipment | Maximum
Property, Plant and Equipment, Useful life	7 years
Office equipment
Property, Plant and Equipment, Useful life	5 years
Furniture and fixtures
Property, Plant and Equipment, Useful life	10 years
Computer equipment
Property, Plant and Equipment, Useful life	3 years

Basis of Presentation, Signif_6

Basis of Presentation, Significant Accounting Policies and Fair Value Measurements - Common Stock Equivalent Shares Excluded From Calculation of Diluted Net Loss Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	11,648,571	8,601,571
Employee Stock Option [Member]
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	9,513,039	7,757,017
Restricted Stock Units
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	1,685,532	399,349
Warrants
Anti-dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (in shares)	450,000	445,205

Basis of Presentation, Signif_7

Basis of Presentation, Significant Accounting Policies and Fair Value Measurements - Fair Value of Financial Assets and Financial Liabilities (Details) - Money market mutual funds (cash equivalents) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Reported Value Measurement
Fair Value of Financial Instruments
Money market funds	$ 79,912	$ 92,283
Fair Value, Inputs, Level 1 | Estimate of Fair Value Measurement
Fair Value of Financial Instruments
Money market funds	$ 79,912	$ 92,283

Property, Plant, and Equipmen_2

Property, Plant, and Equipment - Schedule of Property, plant and equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Total property, plant and equipment	$ 19,794	$ 18,265
Accumulated depreciation and amortization	(15,314)	(14,114)
Property, plant and equipment, net	4,480	4,151
Lab and build-to-suit equipment
Total property, plant and equipment	6,834	6,257
Office equipment
Total property, plant and equipment	19	19
Furniture and fixtures
Total property, plant and equipment	241	134
Computer equipment
Total property, plant and equipment	487	291
Leasehold improvements
Total property, plant and equipment	11,409	11,409
Construction-in-progress
Total property, plant and equipment	$ 804	$ 155

Property, Plant, and Equipmen_3

Property, Plant, and Equipment - Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment
Depreciation and amortization expense	$ 1.2	$ 1.4
Maintenance and repairs	$ 0.3	$ 0.3

Contract Acquisition Costs an_3

Contract Acquisition Costs and Intangible Asset, and Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2020
Contract Acquisition Costs and Intangible Asset, and Goodwill
Business Combination, Amortization Expense	$ 700	$ 1,500
Amortization of Intangible Assets, Total	300	700
Goodwill	$ 3,903	$ 3,903
Liquidia PAH
Contract Acquisition Costs and Intangible Asset, and Goodwill
Goodwill			$ 3,900

Contract Acquisition Costs an_4

Contract Acquisition Costs and Intangible Asset, and Goodwill - Contract acquisition costs and intangible asset (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Contract Acquisition Costs and Intangible Asset, and Goodwill
Contract acquisition costs, Gross Carrying Amount	$ 12,980	$ 12,980
Intangible asset, Gross Carrying Amount	5,620	5,620
Contract acquisition costs, Accumulated Amortization	(5,058)	(4,376)
Intangible asset, Accumulated Amortization	(2,190)	(1,894)
Contract acquisition costs, Net Carrying Amount	7,922	8,604
Intangible asset, Net Carrying Amount	$ 3,430	$ 3,726

Indemnification Asset with Re_2

Indemnification Asset with Related Party and Litigation Finance Payable (Details)	Nov. 01, 2024
PBM | Subsequent Events.
Indemnification Asset with Related Party and Litigation Finance Payable
Major stockholder ownership percentage of Liquidia Corporation Common Stock	8.30%

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued Expenses and Other Current Liabilities
Accrued compensation	$ 8,544	$ 2,862
Accrued research and development expenses	2,902	1,757
Accrued other expenses	1,954	903
Total accrued expenses and other current liabilities	$ 13,400	$ 5,522

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands						12 Months Ended
	Dec. 12, 2023	Apr. 18, 2022	Apr. 12, 2022	Mar. 31, 2022	Nov. 18, 2020	Dec. 31, 2023	Dec. 31, 2022
Common Stock and Preferred Stock, Shares Authorized (in shares)						110,000,000
Common Stock and Preferred Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001
Common stock, shares authorized (in shares)						100,000,000	80,000,000
Preferred stock, shares authorized (in shares)						10,000,000	10,000,000
Sale of common stock, net						$ 24,106	$ 54,461
Merger With RareGen LLC
Number of common shares issued to RareGen's members					5,550,000
Merger With RareGen LLC | Holdback Shares
Number of common shares issued to RareGen's members				616,666
A&R SVB Warrant
Class of Warrant or Right, Outstanding (in shares)						250,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 5.14
SVB Warrant Initial Tranche
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
SVB Warrant - Term B and Term C Tranches
Class of Warrant or Right, Outstanding (in shares)						100,000
Other Warrants
Class of Warrant or Right, Outstanding (in shares)						65,572
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 0.02
Warrants to Purchase Common Stock
Class of Warrant or Right, Exercised During Period (in shares)						0	0
Private Placement | Roger Jeffs
Stock Issued During Period, Shares, New Issues (in shares)	139,665
Shares Issued, Price Per Share (in dollars per share)	$ 7.16
Proceeds from Issuance of Private Placement	$ 1,000
Underwritten Public Offering
Stock Issued During Period, Shares, New Issues (in shares)	3,491,620		11,274,510
Shares Issued, Price Per Share (in dollars per share)	$ 7.16		$ 5.10
Proceeds from Issuance of Common Stock, Net	$ 25,000	$ 54,500
Payments for offering costs						$ 1,900
Underwritten Public Offering | Caligan and Paul B. Manning
Sale of common stock, net	$ 10,000	$ 11,000
Underwritten Public Offering | Caligan
Stock Issued During Period, Shares, New Issues (in shares)		1,764,705				1,117,318
Sale of common stock, net		$ 9,000				$ 8,000
Underwritten Public Offering | Mr. Paul B. Manning
Stock Issued During Period, Shares, New Issues (in shares)		392,156				279,330
Sale of common stock, net		$ 2,000				$ 2,000

Stock-Based Compensation - Othe

Stock-Based Compensation - Other (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended	12 Months Ended
	Jan. 01, 2024	Dec. 31, 2020	Nov. 30, 2020	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Jan. 25, 2022
Number of shares issued			1%
Number of common stock shares outstanding			150,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)					1,463,846
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)					$ 6.57
Cash proceeds from options exercised					$ 495	$ 837
Aggregate intrinsic value of options exercised					468	553
Fair value of options vested					$ 10,143	$ 4,427
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)					1,508,166
Vested (in shares)					201,880
Common Stock
Issuance of common stock under employee stock purchase plan (in shares)					140,922	51,941
Share Price (in dollars per share)					$ 12.03
Chief Executive Officer
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
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares				1,375,000
Modified stock-based compensation						$ 2,900
The 2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award, Percent Annual Increase in Capital Shares Reserved for Future Issuance					4%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)					72,337
Common Stock, Capital Shares Reserved for Future Issuance ( in shares)					655,341
The 2020 Plan | Subsequent Events.
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	2,745,183
2022 Inducement Plan
Common Stock, Capital Shares Reserved for Future Issuance ( in shares)					26,650		310,000
Employee Stock Purchase Plan
Common Stock, Capital Shares Reserved for Future Issuance ( in shares)					707,137
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent					85%
Issuance of common stock under employee stock purchase plan (in shares)					140,922	51,941
Employee Stock Purchase Plan | Subsequent Events.
Available of issuance under the ESPP	150,000

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Total stock-based compensation expense	$ 10,089	$ 9,298
Research and development
Total stock-based compensation expense	2,294	1,409
General and administrative
Total stock-based compensation expense	$ 7,795	$ 7,889

Stock-Based Compensation - Unam

Stock-Based Compensation - Unamortized Compensation Expense (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Employee Stock Option [Member]
Stock-based awards, unamortized expense	$ 15,395
Stock-based awards, weighted average remaining recognition period (Year)	2 years 2 months 12 days
Restricted Stock Units
Stock-based awards, unamortized expense	$ 8,347
Stock-based awards, weighted average remaining recognition period (Year)	2 years 10 months 24 days

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of Stock Options Granted and Purchase Rights Issued under the ESPP (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Expected dividend yield	0%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 5.09	$ 3.94
Employee Stock Purchase Plan | Employee Stock Option [Member]
Expected dividend yield
Risk-free interest rate, minimum	3.46%	1.46%
Risk-free interest rate, maximum	4.73%	3.96%
Expected Volatility, minimum	90%	90%
Expected Volatility, maximum	95%	95%
Employee Stock Purchase Plan | Employee Stock Option [Member] | Minimum
Expected life (years)	5 years 9 months 18 days	5 years 9 months 18 days
Employee Stock Purchase Plan | Employee Stock Option [Member] | Maximum
Expected life (years)	6 years 1 month 6 days	6 years 1 month 6 days
Employee Stock Purchase Plan | Employee Purchase Rights
Expected dividend yield
Risk-free interest rate, minimum	5.20%	0.69%
Risk-free interest rate, maximum	5.47%	3.92%
Expected Volatility, minimum	60%	80%
Expected Volatility, maximum	64%	129%
Expected life (years)	6 months	6 months

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stock-Based Compensation
Outstanding, number of shares (in shares)	8,398,262
Outstanding, weighted average exercise price (in dollars per share)	$ 4.49
Granted, number of shares (in shares)	1,463,846
Granted, weighted average exercise price (in dollars per share)	$ 6.57
Exercised, number of shares (in shares)	(137,576)
Exercised, weighted average exercise price (in dollars per share)	$ 3.59
Cancelled, number of shares (in shares)	(150,595)
Cancelled, weighted average exercise price (in dollars per share)	$ 5.60
Outstanding, number of shares (in shares)	9,573,937	8,398,262
Outstanding, weighted average exercise price (in dollars per share)	$ 4.80	$ 4.49
Outstanding, weighted average contractual term (Year)	7 years 9 months 18 days
Outstanding, aggregate intrinsic value	$ 69,440
Exercisable, number of shares (in shares)	5,688,548
Exercisable, weighted average exercise price (in dollars per share)	$ 4.44
Exercisable, weighted average contractual term (Year)	7 years 3 months 18 days
Exercisable, aggregate intrinsic value	$ 43,433
Vested and expected to vest, number of shares (in shares)	8,974,357
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 4.75
Vested and expected to vest, weighted average contractual term (Year)	7 years 8 months 12 days
Vested and expected to vest, aggregate intrinsic value	$ 65,561
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 5.09	$ 3.94

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Stock-Based Compensation
Unvested, number (in shares) | shares	407,726
Unvested , weighted average grant date fair value (in dollars per share) | $ / shares	$ 5.57
Granted, number (in shares) | shares	1,508,166
Granted , weighted average grant date fair value (in dollars per share) | $ / shares	$ 6.50
Vested , number (in shares) | shares	(201,880)
Vested , weighted average grant date fair value (in dollars per share) | $ / shares	$ 5.41
Forfeited, number (in shares) | shares	(56,034)
Forfeited , weighted average grant date fair value (in dollars per share) | $ / shares	$ 6.22
Unvested , number (in shares) | shares	1,657,978
Unvested , weighted average grant date fair value (in dollars per share) | $ / shares	$ 6.41

Revenue From Contracts With C_2

Revenue From Contracts With Customers (Details) - Sandoz - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Aug. 31, 2018	Dec. 31, 2023	Dec. 31, 2022
Promotion Agreement, Payment	$ 20
Contract with Customer, Refund Liability		$ 0.5	$ 0.5
Percentage of Revenue from Promotion Agreement		99%	98%

Income Taxes (Details)

Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Expense (Benefit), Total	$ 0	$ 0
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	13,400,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	0	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total	0	0
Federal Income Tax
Income Tax Expense (Benefit), Total	0	0
Operating Loss Carryforwards, Subject to Expiration	308,600,000
Tax Credit Carryforward, Amount	4,300,000
State Income Tax
Income Tax Expense (Benefit), Total	0	$ 0
Operating Loss Carryforwards, Subject to Expiration	$ 324,600,000

Income Taxes - Components of De

Income Taxes - Components of Deferred Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Tax loss carryforwards	$ 66,956	$ 59,241
Research and development credits	3,942	3,942
R&D section 174 costs	9,446	4,584
Share-based compensation	1,520	4,637
Lease liability	863	1,157
Compensation	1,982	621
Fixed assets	404	369
Patent amortization	396	476
Accrued litigation costs	1,652	1,546
Settlement reserve	130	123
Licensing agreement	2,367	0
OID interest	383	0
Other	21	2
Valuation allowance	(87,963)	(74,549)
Total deferred income tax assets	2,099	2,149
Section 481(a) adjustment	0	21
Intangible assets	1,652	1,546
Right of use asset	447	582
Total deferred income tax liabilities	2,099	2,149
Total net deferred tax	$ 0	$ 0

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Amount
Income tax benefit at statutory rate	$ (16,486,000)	$ (8,613,000)
State income taxes, net of federal tax benefit	(2,553,000)	(1,787,000)
Non-deductible expenses	493,000	1,000
Share-based compensation	2,015,000	310,000
Credits	0	0
Deferred tax true-up	2,823,000	1,159,000
Change in state rate	260,000	1,368,000
Other	34,000	0
Change in valuation allowance	13,414,000	7,562,000
Provision for income taxes	$ 0	$ 0
% of Pretax Earnings
Income tax benefit at statutory rate, percentage	21%	21%
State income taxes, net of federal tax benefit, percentage	3.30%	4.40%
Non-deductible expenses, percentage	0%	0%
Share-based compensation, percentage	(2.60%)	(0.80%)
Credits, percentage	0%	0%
Deferred tax true-up, percentage	(3.60%)	(2.90%)
Change in state rate, percentage	(0.30%)	(3.30%)
Other, percentage	0%	0%
Change in valuation allowance, percentage	(17.80%)	(18.40%)
Provision for income taxes, percentage	0%	0%

Income Taxes - Uncertain Tax Be

Income Taxes - Uncertain Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Beginning balance	$ 390	$ 455
Increases related to current period		(65)
Decreases related to current period	0
Ending balance	$ 390	$ 390
North Carolina corporate income tax rate	2.50%
North Carolina corporate income tax rate expected by 2030	0%
Income tax expense due to the reduction in value of the North Carolina deferred tax assets as a result of the 2021 Appropriations Act	$ 5,700

Leases - Other (Details)

Leases - Other (Details)	12 Months Ended
	Dec. 31, 2023
Leases
Lessee, Finance Lease, Discount Rate	6.50%
Renewal term	5 years
Lessee, Operating Lease, Existence of Option to Extend [true false]	true

Leases - Cost (Details)

Leases - Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Leases
Total Lease Cost	$ 891	$ 947
Research and Development Expense
Leases
Fixed lease cost	702	702
Amortization of lease assets	96	135
General and Administrative Expense
Leases
Fixed lease cost	78	78
Interest Expense
Leases
Interest on lease liabilities	$ 15	$ 32

Leases - Remaining Lease Term a

Leases - Remaining Lease Term and Discount Rates (Details)	Dec. 31, 2023
Leases
Weighted average remaining lease term, Operating leases	2 years 9 months 18 days
Weighted average remaining lease term, Finance leases	1 year 3 months 18 days
Weighted average discount rate, Operating leases	10.30%
Weighted average discount rate, Finance leases	6.50%

Leases - Future Minimum Lease P

Leases - Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Operating Leases
2024	$ 1,317
2025	1,356
2026	1,158
Total minimum lease payments	3,831
Less: interest	(499)
Present value of lease liabilities	3,332
Finance Leases
2024	115
2025	64
2026	0
Total minimum lease payments	179
Less: interest	(8)
Present value of lease liabilities	171
Total
2024	1,432
2025	1,420
2026	1,158
Total minimum lease payments	4,010
Less: interest	(507)
Present value of lease liabilities	$ 3,503

Revenue Interest Financing Pa_3

Revenue Interest Financing Payable - Terms (Details) $ in Thousands						1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 04, 2024 USD ($)	Jan. 03, 2024 USD ($)	Jul. 27, 2023 USD ($)	Jan. 27, 2023 USD ($)	Jan. 09, 2023 USD ($) tranche	Jul. 27, 2023 USD ($)	Dec. 31, 2023 USD ($)	Jan. 04, 2024 USD ($)	Dec. 31, 2023 USD ($)
Revenue Interest Financing Payable
Amount of debt repaid with initial investment from RIFA									$ 2,190
Amount funded under the second tranche							$ 10,000
Revenue interest financing payable							2,615		2,615
Issuance costs							$ 906
Payments Due Third Quarter of 2025
Revenue Interest Financing Payable
One-time fixed payment amount		$ 23,800
Revenue Interest Financing Agreement
Revenue Interest Financing Payable
RIFA, maximum investment amount					$ 100,000
RIFA, number of tranches | tranche					4
RIFA, initial investment amount				$ 32,500
RIFA, total amount funded									42,500
RIFA, Hard Cap percentage					175
Percentage of investment amount to be repaid on final approval					100
Percentage of investment amount to be paid					100
RIFA, internal rate of return					18%
Minimum cash and cash equivalents required to be maintained during next year					$ 7,500
Minimum cash and cash equivalents required to be maintained after December 31, 2024					15,000
Issuance costs									$ 900
Effective annual interest rate									17%
Revenue Interest Financing Agreement | On First $250 Million of Annual Net Revenue
Revenue Interest Financing Payable
RIFA, annual net revenue, threshold					$ 250,000
Revenue Interest Financing Agreement | On First $250 Million of Annual Net Revenue | Minimum
Revenue Interest Financing Payable
RIFA, percentage of royalty payment on annual net revenue					3.60%
Revenue Interest Financing Agreement | On First $250 Million of Annual Net Revenue | Maximum
Revenue Interest Financing Payable
RIFA, percentage of royalty payment on annual net revenue					10.28%
Revenue Interest Financing Agreement | On Second $250 Million of Annual Net Revenue
Revenue Interest Financing Payable
RIFA, annual net revenue, threshold					$ 250,000
Revenue Interest Financing Agreement | On Second $250 Million of Annual Net Revenue | Minimum
Revenue Interest Financing Payable
RIFA, minimum payment to be made, percentage					1.44%
Revenue Interest Financing Agreement | On Second $250 Million of Annual Net Revenue | Maximum
Revenue Interest Financing Payable
RIFA, minimum payment to be made, percentage					4.11%
Revenue Interest Financing Agreement | In Excess of $500 Million of Annual Net Revenue
Revenue Interest Financing Payable
RIFA, annual net revenue, threshold					$ 500,000
Revenue Interest Financing Agreement | In Excess of $500 Million of Annual Net Revenue | Minimum
Revenue Interest Financing Payable
RIFA, Hard Cap percentage					0.36
Revenue Interest Financing Agreement | In Excess of $500 Million of Annual Net Revenue | Maximum
Revenue Interest Financing Payable
RIFA, Hard Cap percentage					1.03
Revenue Interest Financing Agreement | Funding Amount by December 31, 2026
Revenue Interest Financing Payable
RIFA, minimum payment to be made, percentage					60%
Revenue Interest Financing Agreement | Funding Amount by December 31, 2028
Revenue Interest Financing Payable
RIFA, minimum payment to be made, percentage					100%
Revenue Interest Financing Agreement | A&R Silicon Valley Bank Term Loan
Revenue Interest Financing Payable
Amount of debt repaid with initial investment from RIFA				$ 22,200
Second and Third Amendments to Revenue Interest Financing Agreement
Revenue Interest Financing Payable
Amount moved from fourth tranche to second tranche						$ 2,500
Amount to be funded under the second tranche.						$ 10,000
Amount funded under the second tranche			$ 10,000
Fourth Amendment to Revenue Interest Financing Agreement | Subsequent Events.
Revenue Interest Financing Payable
Amount to be funded under the second tranche.		35,000
Amount funded under the second tranche	$ 25,000							$ 35,000
Amount moved from third tranche to second tranche		25,000
Amount to be funded under third tranche		10,000
Amount to be funded under fourth tranche		22,500
Fourth Amendment to Revenue Interest Financing Agreement | Payments Beginning Second Quarter 2024
Revenue Interest Financing Payable
Quarterly fixed payment amount		1,000
Fourth Amendment to Revenue Interest Financing Agreement | Payments Beginning Third Quarter of 2025 through 2028
Revenue Interest Financing Payable
Quarterly fixed payment amount		5,800
Fourth Amendment to Revenue Interest Financing Agreement | HCR | Subsequent Events.
Revenue Interest Financing Payable
Amount to be funded under third tranche		10,000
Amount to be funded under fourth tranche		$ 22,500

Revenue Interest Financing Pa_4

Revenue Interest Financing Payable - Summary (Details) $ in Thousands	11 Months Ended	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Revenue Interest Financing Payable
Balance as of January 27, 2023 closing	$ 32,500
Issuance costs	(906)
Second tranche funding	10,000
Accretion	5,974
Amortization of issuance costs	119
Payments	(1,654)	$ (1,654)
Balance as of December 31, 2023	46,033	46,033
Less: current portion of revenue interest financing payable	(2,615)	(2,615)
Long-term portion of revenue interest financing payable	$ 43,418	$ 43,418

Long-Term Debt - Summary (Detai

Long-Term Debt - Summary (Details) $ in Thousands	Dec. 31, 2022 USD ($)
A&R Silicon Valley Bank Term Loan
Long-Term Debt
Long-term debt	$ 19,879

Long-Term Debt - Terms (Details

Long-Term Debt - Terms (Details) - USD ($)				12 Months Ended
	Jan. 27, 2023	Jan. 09, 2023	Jan. 07, 2022	Dec. 31, 2023	Dec. 31, 2022
Long-Term Debt
Repayments of Debt				$ 2,190,000
Loss on extinguishment of debt				2,311,000	$ 997,000
Repayments of debt				$ 20,000,000	10,500,000
Warrants included in additional paid-in capital					1,317,000
Long-term debt, noncurrent					19,879,000
Revenue Interest Financing Agreement.
Long-Term Debt
Revenue Interest Financing Agreement, Maximum Investment Amount		$ 100,000,000
Revenue Interest Financing Agreement, Initial Investment Amount	$ 32,500,000
A&R SVB Warrants
Long-Term Debt
Warrants included in additional paid-in capital			$ 1,300,000
Gain (loss) extinguishment component			700,000
Debt discount			$ 600,000
A&R SVB Warrants | SVB
Long-Term Debt
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			250,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 5.14
SVB Warrant Initial Tranche
Long-Term Debt
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 3.05
Class of Warrant or Right, Outstanding (in shares)				100,000
Loan and Security Agreement with SVB
Long-Term Debt
Repayments of Debt			$ 10,500,000
Loss on extinguishment of debt					$ 1,000,000
Silicon Valley Bank Term Loan
Long-Term Debt
Long-term debt, noncurrent			$ 19,400,000
Amended and Restated Loan and Security Agreement
Long-Term Debt
Debt Instrument, Final Payment Fees, Percentage			5%
Debt instrument, final payment			$ 185,000
A&R Silicon Valley Bank Term Loan
Long-Term Debt
Interest rate threshold used in determining the floating interest rate at which interest accrues on the debt instrument			7.25%
Prime interest rate threshold used in determining the floating interest rate at which interest accrues on the debt instrument			4%
A&R Silicon Valley Bank Term Loan | Revenue Interest Financing Agreement.
Long-Term Debt
Repayments of Debt	$ 22,200,000
A&R Silicon Valley Bank Term Loan | Maximum
Long-Term Debt
Debt Issuance Costs, Noncurrent, Net			$ 100,000
Amended and Restated Loan and Security Agreement Tranche One
Long-Term Debt
Proceeds from Lines of Credit			$ 20,000,000

Long-Term Debt - SVB Warrant Fa

Long-Term Debt - SVB Warrant Fair Value (Details) - A&R SVB Warrants	Dec. 31, 2023 Y
Measurement Input, Risk-free interest rate
Long-Term Debt, Fair Value of Warrant
Warrant outstanding, Measurement input	0.0176
Measurement Input, Expected volatility
Long-Term Debt, Fair Value of Warrant
Warrant outstanding, Measurement input	0.972
Measurement Input, Expected life (years)
Long-Term Debt, Fair Value of Warrant
Warrant outstanding, Measurement input	10

Defined Contribution Retireme_2

Defined Contribution Retirement Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Defined Contribution Retirement Plan
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	100%
Maximum percentage of an employee's salary matched by the Company	4%
Defined Contribution Plan, Cost	$ 0.7	$ 0.4

Legal Proceedings (Details)

Legal Proceedings (Details) $ in Thousands	Apr. 21, 2021 USD ($)
Liquidia PAH and Sandoz | UTC and Smiths Medical Litigation | Pending Litigation
Legal Proceedings
Proceeds from Legal Settlements	$ 4,250

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
	Jul. 14, 2023	Jun. 30, 2023	Dec. 31, 2023
Pharmosa License Agreement
Upfront license fee to be paid		$ 10
Maximum potential development milestone payments		30
Maximum potential sales milestones		185
Milestone payments Pharmosa is to receive per terms of the license agreement		$ 10
Chasm Technologies
Maximum Net Sales Threshold As Basis For Payment Of Future Contingent Royalties			$ 1.5
Net sales earned relating to payment of future contingent royalties			0.2
Agreement With LGM Pharma, LLC
Purchase Commitment, Remaining Minimum Amount Committed			2.7
Annual minimum, amount paid to date			$ 2.7
Expiration term of agreement			5 years
Amended and Restated Commercial Manufacturing Services and Supply Agreement with Lonza Tampa LLC
Initial term	5 years
Termination term for FDA rejection	60 days
Termination term for FDA delay	120 days
Percentage of reimburse	50%
Aggregate exceed	$ 2.5
Term of submission	24 months
Initial term	12 months
Non-cancelable commitments for product manufacturing costs			$ 4.1

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands				11 Months Ended	12 Months Ended
	Jan. 08, 2024	Jan. 04, 2024	Jan. 03, 2024	Dec. 31, 2023	Jan. 04, 2024
Subsequent Events
Amount funded under the second tranche				$ 10,000
Subsequent Events. | Private Placement
Subsequent Events
Payments for offering costs		$ 100
Fourth Amendment to Revenue Interest Financing Agreement | Subsequent Events.
Subsequent Events
Amount moved from third tranche to second tranche			$ 25,000
Amount funded under the second tranche		$ 25,000			$ 35,000
Amount to be funded under third tranche			10,000
Amount to be funded under fourth tranche			22,500
Legend Aggregator, LP | Subsequent Events. | Private Placement
Subsequent Events
Stock Issued During Period, Shares, New Issues (in shares)		7,182,532
Shares Issued, Price Per Share (in dollars per share)		$ 10.442			$ 10.442
Proceeds from Issuance of Private Placement	$ 75,000	$ 75,000
Payments for offering costs		$ 100
HCR | Fourth Amendment to Revenue Interest Financing Agreement | Subsequent Events.
Subsequent Events
Amount to be funded under third tranche			10,000
Amount to be funded under fourth tranche			$ 22,500

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (78,502)	$ (41,015)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Name ​ Title ​ Date of Adoption of Rule 10b5-1 Trading Arrangement (1) ​ Scheduled Expiration Date of Rule 10b5-1 Trading Arrangement ​ Aggregate Number of Securities to Be Sold Roger A. Jeffs, Ph.D. ​ Chief Executive Officer and Director ​ 12/15/2023 (2) ​ Until final settlement of any covered RSU or PSU ​ Indeterminable (3) Michael Kaseta ​ Chief Operating Officer and Chief Financial Officer ​ 12/15/2023 (2) ​ Until final settlement of any covered RSU or PSU ​ Indeterminable (3) Russell Schundler ​ General Counsel and Secretary ​ 12/15/2023 (2) ​ Until final settlement of any covered RSU or PSU ​ Indeterminable (3) Rajeev Saggar, M.D. ​ Chief Medical Officer ​ 12/15/2023 (2) ​ Until final settlement of any covered RSU or PSU ​ Indeterminable (3) Scott Moomaw ​ Chief Commercial Officer ​ 12/15/2023 (2) ​ Until final settlement of any covered RSU or PSU ​ Indeterminable (3) Jason Adair ​ Chief Business Officer ​ 12/15/2023 (2) ​ Until final settlement of any covered RSU or PSU ​ Indeterminable (3) (1) Date of adoption of Rule 10b5-1 trading arrangements is in accordance with both the Company’s insider trading policy and applicable SEC rules and regulations. (2) The first trade pursuant to the Rule 10b5-1 trading arrangement will be, in accordance with both the Company’s insider trading policy and applicable SEC rules and regulations, on a date after the date of adoption of the Rule 10b5-1 trading arrangement. (3) The number of shares of common stock subject to covered restricted stock units (“RSUs”) or performance stock units (“PSUs”) that will be sold to satisfy applicable tax withholding obligations upon vesting is unknown as the number will vary based on the extent to which vesting conditions are satisfied, the market price of our common stock at the time of settlement and the potential future grant of additional RSUs or PSUs subject to this arrangement. This trading arrangement, which applies to RSUs or PSUs whether vesting is based on the passage of time and/or the achievement of performance goals, provides for the automatic sale of shares that would otherwise be issuable on each settlement date of a covered RSU or PSU in an amount sufficient to satisfy the applicable withholding obligation, with the proceeds of the sale delivered to us in satisfaction of the applicable withholding obligation.
Roger A. Jeffs
Trading Arrangements, by Individual
Name	Roger A. Jeffs, Ph.D.
Title	Chief Executive Officer and Director
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	12/15/2023
Michael Kaseta
Trading Arrangements, by Individual
Name	Michael Kaseta
Title	Chief Operating Officer and Chief Financial Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	12/15/2023
Russell Schundler
Trading Arrangements, by Individual
Name	Russell Schundler
Title	General Counsel and Secretary
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	12/15/2023
Rajeev Saggar
Trading Arrangements, by Individual
Name	Rajeev Saggar, M.D.
Title	Chief Medical Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	12/15/2023
Scott Moomaw
Trading Arrangements, by Individual
Name	Scott Moomaw
Title	Chief Commercial Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	12/15/2023
Jason Adair
Trading Arrangements, by Individual
Name	Jason Adair
Title	Chief Business Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	12/15/2023