Immunic (IMUX) 10-Q 8 May 24 2024 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2024	May 02, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	001-36201
Entity Registrant Name	Immunic, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	56-2358443
Entity Address, Address Line One	1200 Avenue of the Americas
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	New York,
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10036
City Area Code	332
Local Phone Number	255-9818
Title of 12(b) Security	Common Stock, $0.0001 par value
Trading Symbol	IMUX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		90,079,016
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0001280776

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 97,312	$ 46,674
Other current assets and prepaid expenses	5,303	5,860
Total current assets	102,615	52,534
Property and equipment, net	442	466
Right-of-use assets, net	1,098	1,299
Total assets	104,155	54,299
Current liabilities:
Accounts payable	6,767	5,099
Accrued expenses	12,419	18,664
Other current liabilities	960	966
Total current liabilities	20,146	24,729
Long-term liabilities
Operating lease liabilities	433	639
Total long-term liabilities	433	639
Total liabilities	20,579	25,368
Commitments and contingencies (Note 4)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 20,000,000 authorized and no shares issued or outstanding as of March 31, 2024 and December 31, 2023	0	0
Common stock, $0.0001 par value; 500,000,000 and 130,000,000 shares authorized as of March 31, 2024 and December 31, 2023, respectively, and 90,079,016 and 45,177,730 shares issued and outstanding as of March 31, 2024 and December 31, 2023, respectively	8	4
Additional paid-in capital	519,757	436,060
Accumulated other comprehensive income	4,287	3,759
Accumulated deficit	(440,476)	(410,892)
Total stockholders’ equity	83,576	28,931
Total liabilities and stockholders’ equity	$ 104,155	$ 54,299

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred stock, par value (in USD per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in USD per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	500,000,000	130,000,000
Common stock, shares issued (in shares)	90,079,016	45,177,730
Common stock, shares outstanding (in shares)	90,079,016	45,177,730

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating expenses:
Research and development	$ 18,736	$ 22,963
General and administrative	5,145	4,288
Total operating expenses	23,881	27,251
Loss from operations	(23,881)	(27,251)
Other income (expense):
Interest income	1,187	800
Change in fair value of the tranche rights	(4,796)	0
Other income (expense), net	(2,094)	1,179
Total other income (expense)	(5,703)	1,979
Net loss	$ (29,584)	$ (25,272)
Net loss per share, basic (in USD per share)	$ (0.30)	$ (0.58)
Net loss per share, diluted (in USD per share)	$ (0.30)	$ (0.58)
Weighted-average common shares outstanding, basic (in shares)	97,299,955	43,664,783
Weighted-average common shares outstanding, diluted (in shares)	97,299,955	43,664,783

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net loss	$ (29,584)	$ (25,272)
Other comprehensive income:
Foreign currency translation	528	776
Total comprehensive loss	$ (29,056)	$ (24,496)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	January 2024 PIPE Transaction	At The Market Sales Agreement	Common Stock	Common Stock January 2024 PIPE Transaction	Common Stock At The Market Sales Agreement	Additional Paid-In Capital	Additional Paid-In Capital January 2024 PIPE Transaction	Additional Paid-In Capital At The Market Sales Agreement	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2022				39,307,286
Beginning balance at Dec. 31, 2022	$ 113,684			$ 4			$ 427,925			$ 3,035	$ (317,280)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(25,272)										(25,272)
Stock-based compensation	1,979						1,979
Foreign currency translation	776
Foreign exchange translation adjustment	776									776
Shares issued from exercise of pre-funded warrants (in shares)				5,096,552
Shares issued from exercise of pre-funded warrants	51						51
Ending balance (in shares) at Mar. 31, 2023				44,403,838
Ending balance at Mar. 31, 2023	$ 91,218			$ 4			429,955			3,811	(342,552)
Beginning balance (in shares) at Dec. 31, 2023	45,177,730			45,177,730
Beginning balance at Dec. 31, 2023	$ 28,931			$ 4			436,060			3,759	(410,892)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(29,584)										(29,584)
Stock-based compensation	2,750						2,750
Foreign currency translation	528									528
Issuance of common stock (in shares)					44,751,286	150,000
Issuance of common stock		$ 52,364	$ 191		$ 4			$ 52,360	$ 191
Conversion of tranche rights liability to equity	$ 28,396						28,396
Ending balance (in shares) at Mar. 31, 2024	90,079,016			90,079,016
Ending balance at Mar. 31, 2024	$ 83,576			$ 8			$ 519,757			$ 4,287	$ (440,476)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders’ Equity (Parenthetical) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
January 2024 PIPE Transaction
Issuance costs	$ 4,037
At The Market Sales Agreement
Issuance costs	$ 6

Condensed Consolidated Statem_5

Condensed Consolidated Statement of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net loss	$ (29,584)	$ (25,272)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	26	32
Unrealized foreign currency loss	340	516
Stock-based compensation	2,750	1,979
Change in fair value of tranche rights	4,796	0
Fees expensed as part of January 2024 Financing	1,690	0
Changes in operating assets and liabilities:
Other current assets and prepaid expenses	389	123
Accounts payable	1,794	986
Accrued expenses	(6,145)	2,072
Other liabilities	(25)	51
Net cash used in operating activities	(23,969)	(19,513)
Cash flows from investing activities:
Sale of investments - other	0	5,439
Purchases of property and equipment	(31)	(104)
Net cash provided by (used in) investing activities	(31)	5,335
Cash flows from financing activities:
Proceeds from public offering of common stock through At The Market Sales Agreement, net	191	0
Proceeds from the exercise of pre-funded warrants	0	51
Proceeds from January 2024 Financing, net of issuance costs	74,273	0
Net cash provided by financing activities	74,464	51
Effect of exchange rate changes on cash and cash equivalents	174	143
Net change in cash and cash equivalents	50,638	(13,984)
Cash and cash equivalents, beginning of period	46,674	106,745
Cash and cash equivalents, end of period	97,312	92,761
Supplemental disclosure of noncash investing and financing activities:
Conversion of tranche rights liability to equity upon increase in authorized shares	28,396	0
Operating lease right-of use asset obtained in exchange for lease liability	$ 0	$ 544

Description of Business and Bas

Description of Business and Basis of Financial Statements	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Description of Business and Basis of Financial Statements	Description of Business and Basis of Financial Statements Description of Business Immunic, Inc. ("Immunic" or the "Company") is a biotechnology company developing a clinical pipeline of selective oral immunology therapies focused on treating chronic inflammatory and autoimmune diseases. The Company is headquartered in New York City with its main operations in Gräfelfing near Munich, Germany. The Company had approximately 80 employees as of May 1, 2024. The Company is pursuing clinical development of orally administered, small molecule programs, each of which has unique features intended to directly address the unmet needs of patients with serious chronic inflammatory and autoimmune diseases. These include the vidofludimus calcium (IMU-838) program, which is in Phase 3 clinical development for patients with multiple sclerosis (“MS”) and which has shown therapeutic activity in Phase 2 clinical trials in patients suffering from relapsing-remitting MS, progressive MS and moderate-to-severe ulcerative colitis (“UC”); the IMU-856 program, which is targeted to regenerate bowel epithelium and restore intestinal barrier function, which could potentially be applicable in numerous gastrointestinal diseases, such as celiac disease, inflammatory bowel disease, short bowel syndrome and irritable bowel syndrome with diarrhea; and the IMU-381 program, which is a next generation molecule being developed to specifically address the needs of gastrointestinal diseases. The Company’s business, operating results, financial condition and growth prospects are subject to significant risks and uncertainties, including the failure of its clinical trials to meet their endpoints, failure to obtain regulatory approval and needing additional funding to complete the development and commercialization of the Company's three development programs. Liquidity and Financial Condition Immunic has no products approved for commercial sale and has not generated any revenue from product sales. It has never been profitable and has incurred operating losses in each year since inception in 2016. The Company has an accumulated deficit of approximately $440.5 million as of March 31, 2024 and $410.9 million as of December 31, 2023. Substantially all of Immunic's operating losses resulted from expenses incurred in connection with its research and development programs and from general and administrative costs associated with its operations. Immunic expects to incur significant expenses and increasing operating losses for the foreseeable future as it initiates and continues the development of its product candidates and adds personnel necessary to advance its pipeline of product candidates. Immunic expects that its operating losses will fluctuate significantly from quarter-to-quarter and year-to-year due to timing of development programs. From inception through March 31, 2024, Immunic has raised net cash of approximately $430.9 million from private and public offerings of preferred stock, common stock, pre-funded warrants and tranche rights. As of March 31, 2024, the Company had cash and cash equivalents of approximately $97.3 million. With these funds, Immunic expects to be able to fund its operations beyond twelve months from the date of the issuance of the accompanying condensed consolidated financial statements. Basis of Presentation and Consolidation The accompanying consolidated financial statements have been prepared in conformity with United States generally accepted accounting principles ("U.S. GAAP") and include the accounts of Immunic and its wholly-owned subsidiaries, Immunic AG and Immunic Australia Pty Ltd. All intercompany accounts and transactions have been eliminated in consolidation. Immunic manages its operations as a single reportable segment for the purposes of assessing performance and making operating decisions. Unaudited Interim Financial Information Immunic has prepared the accompanying interim unaudited condensed consolidated financial statements in accordance with United States generally accepted accounting principles, (“US GAAP”), for interim financial information and with the

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires the Company to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, expenses and the disclosure of contingent assets and liabilities in the Company’s consolidated financial statements. The most significant estimates in the Company’s financial statements and accompanying notes relate to clinical trial expenses and share-based compensation. Management believes its estimates to be reasonable under the circumstances. Actual results could differ materially from those estimates and assumptions. Foreign Currency Translation and Presentation The Company’s reporting currency is United States (“U.S.”) dollars. Immunic AG is located in Germany with the euro being its functional currency. Immunic Australia Pty Ltd.’s functional currency is the Australian dollar. All amounts in the financial statements where the functional currency is not the U.S. dollar are translated into U.S. dollar equivalents at exchange rates as follows: • assets and liabilities at reporting period-end rates; • income statement accounts at average exchange rates for the reporting period; and • components of equity at historical rates. Gains and losses from translation of the financial statements into U.S. dollars are recorded in stockholders’ equity as a component of accumulated other comprehensive income (loss). Realized and unrealized gains and losses resulting from foreign currency transactions denominated in currencies other than the functional currency are reflected as general and administrative expenses in the Consolidated Statements of Operations. Foreign currency transaction gains and losses related to long-term intercompany loans that are payable in the foreseeable future are recorded in Other Income (Expense). The Consolidated Statements of Cash Flows were prepared by using the average exchange rate in effect during the reporting period which reasonably approximates the timing of the cash flows. Cash and Cash Equivalents and Investments- other The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Cash and cash equivalents consist of cash on hand and deposits in banks located in the U.S. of approximately $73.2 million, Germany of approximately $22.5 million and Australia of approximately $1.6 million as of March 31, 2024. The Company maintains cash and cash equivalent balances denominated in Euro and U.S. dollars with major financial institutions in the U.S. and Germany in excess of the deposit limits insured by the government. Management periodically reviews the credit standing of these financial institutions. The Company currently deposits its cash and cash equivalents with two large financial institutions. Cash and Cash equivalents in the U.S. are held at JP Morgan and are primarily held in a U.S. Government money market fund account earning interest at a rate of 5.2% during the period ended March 31, 2024. Cash and cash equivalents in Germany are earning interest at a rate of 3.5% to 3.75% during the period ended March 31, 2024. Fair Value Measurement Fair value is defined as the price that would be received to sell an asset or be paid to transfer a liability in an orderly transaction between market participants on the measurement date. Accounting guidance establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value: Level 1—Quoted prices in active markets for identical assets or liabilities. Level 1 assets consisted of money market funds for the periods presented. The Company had no Level 1 liabilities for the periods presented. Level 2—Inputs other than observable quoted prices for the asset or liability, either directly or indirectly; these include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. The Company had no Level 2 assets or liabilities for the periods presented. Level 3—Unobservable inputs to the valuation methodology that are significant to the measurement of the fair value of assets or liabilities. The Company had no Level 3 assets or liabilities for the periods presented. The carrying value of cash and cash equivalents, other current assets and prepaid expenses, accounts payable, accrued expenses, and other current liabilities approximates fair value due to the short period of time to maturity. Property and Equipment Property and equipment is stated at cost. Depreciation is computed using the straight-line method based on the estimated service lives of the assets, which range from three Impairment of Long-Lived Assets The Company records impairment losses on long-lived assets used in operations when indicators of impairment are present and the undiscounted cash flows estimated to be generated by those assets are less than the assets’ carrying amount. Impaired assets are then recorded at their estimated fair value. There were no impairment losses during the three months ended March 31, 2024 and 2023. Research and Development Expenses These costs primarily include external development expenses and internal personnel expenses for its development programs, vidofludimus calcium and IMU-856. Immunic has spent the majority of its research and development resources on vidofludimus calcium, the Company's lead development program, for clinical trials in MS and UC. Research and development expenses consist of expenses incurred in research and development activities, which include clinical trials, contract research services, certain milestone payments, salaries and related employee benefits, allocated facility costs and other outsourced services. Research and development expenses are charged to operations as incurred. The Company enters into agreements with contract research organizations (“CROs”) to provide clinical trial services for individual studies and projects by executing individual work orders governed by a Master Service Arrangement (“MSA”). The MSAs and associated work orders provide for regular recurrent payments and payments upon the completion of certain milestones. The Company regularly assesses the timing of payments against actual costs incurred to ensure a proper accrual of related expenses in the appropriate accounting period. Collaboration Arrangements Certain collaboration and license agreements may include payments to or from the Company of one or more of the following: non-refundable or partially refundable upfront or license fees; development, regulatory and commercial milestone payments; payment for manufacturing supply services; partial or complete reimbursement of research and development costs; and royalties on net sales of licensed products. The Company assesses whether such contracts are within the scope of Financial Accounting Standards Board (FASB) Accounting Standards Update (“ASU”) 2014-09 “ Revenue from Contracts with Customers ” and ASU No. 2018-18, “ Collaborative Arrangements” ("ASU 2018-18"). ASU 2018-18, clarifies that certain elements of collaborative arrangements could qualify as transactions with customers in the scope of ASC 606. In October 2018, the Company entered into an option and license agreement (the "Daiichi Sankyo Agreement") with Daiichi Sankyo Co., Ltd. ("Daiichi Sankyo") which granted the Company the right to license a group of compounds, designated by the Company as IMU-856, as a potential new oral treatment option for gastrointestinal diseases such as celiac disease, inflammatory bowel disease, irritable bowel syndrome with diarrhea and other barrier function associated diseases. During the option period, the Company performed agreed upon research and development activities for which it was reimbursed by Daiichi Sankyo up to a maximum agreed-upon limit. Such reimbursement was recorded as other income. There are no additional research and development reimbursements expected under this agreement. On January 5, 2020, the Company exercised its option to obtain the exclusive worldwide right to commercialization of IMU-856. Among other things, the option exercise grants Immunic AG the rights to Daiichi Sankyo’s patent application related to IMU-856, for which the Company received a notice of allowance from the U.S. Patent & Trademark Office in August 2022. In connection with the option exercise, the Company paid a one-time upfront licensing fee to Daiichi Sankyo. Under the Daiichi Sankyo Agreement, Daiichi Sankyo is also eligible to receive future development, regulatory and sales milestone payments, as well as royalties related to IMU-856. Government assistance Government assistance relating to research and development performed by Immunic Australia is recorded as a component of other (income) expense. This government assistance is recognized at a rate of 43.5% of the qualified research and development expenditures which are incurred. We also receive government assistance from the German Government for reimbursement of research and development expenses up to one million Euros per year. We recognized $36,000 and $1.8 million of other income General and Administrative Expenses General and administrative expenses consist primarily of salaries and related costs for personnel in executive, finance, business development and other support functions. Other general and administrative expenses include, but are not limited to, stock-based compensation, insurance costs, professional fees for legal, accounting and tax services, consulting, related facility costs and travel. Stock-Based Compensation The Company measures the cost of employee and non-employee services received in exchange for equity awards based on the grant-date fair value of the award recognized generally as an expense (i) on a straight-line basis over the requisite service period for those awards whose vesting is based upon a service condition, and (ii) on an accelerated method for awards whose vesting is based upon a performance condition, but only to the extent it is probable that the performance condition will be met. Stock-based compensation is (i) estimated at the date of grant based on the award’s fair value for equity classified awards and (ii) final measurement date for liability classified awards. Forfeitures are recorded in the period in which they occur. The Company estimates the fair value of stock options using the Black-Scholes-Merton option-pricing model ("BSM"), which requires the use of estimates and subjective assumptions, including the risk-free interest rate, the fair value of the underlying common stock, the expected dividend yield of the Company’s common stock, the expected volatility of the price of the Company’s common stock, and the expected term of the option. These estimates involve inherent uncertainties and the application of management’s judgment. If factors change and different assumptions are used, the Company’s stock-based compensation expense could be materially different in the future. Leases The Company leases office space and office equipment. The underlying lease agreements have lease terms of less than 12 months and up to 60 months. Leases with terms of 12 months or less at inception are not included in the operating lease right of use asset and operating lease liability. The Company has three existing leases for office and laboratory space. At inception of a lease agreement, the Company determines whether an agreement represents a lease and at commencement each lease agreement is assessed as to classification as an operating or financing lease. The Company's leases have been classified as operating leases and an operating lease right-of-use asset and an operating lease liability have been recorded on the Company’s balance sheet. A right-of-use lease asset represents the Company’s right to use the underlying asset for the lease term and the lease obligation represents its commitment to make the lease payments arising from the lease. Right-of-use lease assets and obligations are recognized at the commencement date based on the present value of remaining lease payments over the lease term. As the Company’s leases do not provide an implicit rate, the Company has used an estimated incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The right-of-use lease asset includes any lease payments made prior to commencement and excludes any lease incentives. The lease term used in estimating future lease payments may include options to extend when it is reasonably certain that the Company will exercise that option. Operating lease expense is recognized on a straight-line basis over the lease term, subject to any changes in the lease or changes in expectations regarding the lease term. Variable lease costs such as common area costs and property taxes are expensed as incurred. Leases with an initial term of twelve months or less are not recorded on the balance sheet. Comprehensive Income (Loss) Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. Accumulated other comprehensive income (loss) has been reflected as a separate component of stockholders’ equity in the accompanying Consolidated Balance Sheets and consists of foreign currency translation adjustments (net of tax). Income Taxes The Company is subject to corporate income tax laws and regulations in the U.S., Germany and Australia. Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require significant judgment in their application. The Company utilizes the asset and liability method of accounting for income taxes which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the audited consolidated financial statements. Deferred income tax assets and liabilities are determined based on the differences between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of changes in tax rates on deferred tax assets and liabilities is recognized in operations in the period that includes the enactment date. Deferred taxes are reduced by a valuation allowance when, in the opinion of management, it is more likely than not some portion or the entire deferred tax asset will not be realized. As of March 31, 2024 and 2023, respectively, the Company maintained a full valuation allowance against the balance of deferred tax assets. It is the Company’s policy to provide for uncertain tax positions and the related interest and penalties based upon management’s assessment of whether a tax benefit is more likely than not to be sustained upon examination by tax authorities. The Company recognizes interest and penalties accrued on any unrecognized tax benefits as a component of income tax expense. The Company is subject to U.S. federal, New York, California, Texas, German and Australian income taxes. The Company is subject to U.S. federal or state income tax examination by tax authorities for tax returns filed for the years 2003 and forward due to the carryforward of NOLs. Tax years 2019 through 2022 are subject to audit by German and Australian tax authorities. The Company is not currently under examination by any tax jurisdictions. Warrants and Tranche Rights The Company accounts for issued financial instruments either as a liability or equity in accordance with ASC 480-10, Accounting for Certain Financial Instruments with Characteristics of both Liabilities and Equity (“ASC 480-10”) or ASC 815-40, Accounting for Derivative Financial Instruments Indexed to, and Potentially Settled in, a Company’s Own Stock (“ASC 815-40”). Under ASC 480-10, financial instruments are considered a liability if they are mandatorily redeemable and they require settlement in cash, other assets, or a variable number of shares. If financial instruments do not meet liability classification under ASC 480-10, the Company considers the requirements of ASC 815-40 to determine whether the financial instruments should be classified as a liability or as equity. Under ASC 815-40, contracts that may require settlement for cash are liabilities, regardless of the probability of the occurrence of the triggering event. Liability-classified financial instruments are measured at fair value on the issuance date and at the end of each reporting period. Any change in the fair value of the financial instruments after the issuance date is recorded in the consolidated statements of operations as a gain or loss. If financial instruments do not require liability classification under ASC 815-40, in order to conclude financial instruments should be classified as equity, the Company assesses whether the financial instruments are indexed to its common stock and whether the financial instruments are classified as equity under ASC 815-40 or other applicable GAAP standard. Equity-classified financial instruments are accounted for at fair value on the issuance date with no changes in fair value recognized after the issuance date. Net Loss Per Share Basic net loss per share attributable to common stockholders is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss by the weighted-average number of common shares and, if dilutive, common stock equivalents outstanding for the period determined using the treasury-stock method. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position. The weighted average shares outstanding calculation for basic and diluted earnings per share for the three months ended March 31, 2024 includes 11,193,564 pre-funded warrants. Potentially dilutive securities, not included in the calculation of diluted net loss per share attributable to common stockholders because to do so would be anti-dilutive, are as follows: As of March 31, 2024 2023 Options to purchase common stock 10,318,323 5,595,841 Recently Issued and/or Adopted Accounting Standards There are no recently issued accounting standards that would have a significant impact on the Company's consolidated financial statements.

Balance Sheet Details

Balance Sheet Details	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance Sheet Details	Balance Sheet Details Other Current Assets and Prepaid Expenses Other Current Assets and Prepaid Expense consist of (in thousands): March 31, 2024 December 31, 2023 Prepaid clinical and related costs $ 2,767 $ 2,314 VAT receivable 770 703 Australian research and development tax incentive 676 670 Research grant — 1,104 Other 1,090 1,069 Total $ 5,303 $ 5,860 Accounts Payable Accounts Payable consist of (in thousands): March 31, 2024 December 31, 2023 Clinical costs $ 6,211 $ 4,726 Legal and audit costs 115 160 Other 441 213 Total $ 6,767 $ 5,099 Accrued Expenses Accrued Expenses consist of (in thousands): March 31, 2024 December 31, 2023 Accrued clinical and related costs $ 11,497 $ 16,863 Accrued legal and audit costs 234 216 Accrued compensation 610 1,460 Accrued other 78 125 Total $ 12,419 $ 18,664 Other Current Liabilities Other Current Liabilities consist of (in thousands): March 31, 2024 December 31, 2023 Lease liabilities $ 697 $ 695 Other 263 271 Total $ 960 $ 966

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Lease The Company leases certain office space under non-cancelable operating leases. The leases terminate on July 31, 2025 for the New York City office, June 30, 2025 for the Gräfelfing, Germany office and November 30, 2028 for the research laboratory in Planegg, Germany. These agreements include both lease (e.g., fixed rent) and non-lease components (e.g., common-area and other maintenance costs). The non-lease components are deemed to be executory costs and are therefore excluded from the minimum lease payments used to determine the present value of the operating lease obligation and related right-of-use asset. The New York City lease was extended on December 22, 2022 for an additional 27 months resulting in the new lease termination date of July 31, 2025. The New York City lease has a renewal option, but this was not included in calculating the right of use asset and liabilities. On April 7, 2020, the Company signed a five year lease for its facility in Gräfelfing, Germany. On March 1, 2021 and August 1, 2022 the Company added additional lease space at the Gräfelfing, Germany office. Renewal options were not included in calculating the right of use asset and liabilities for this facility. In February 2023, the Company leased space in Germany for a research laboratory. The leases do not have concessions, leasehold improvement incentives or other build-out clauses. Further, the leases do not contain contingent rent provisions. The New York City lease had a six month rent holiday at the beginning of the lease as well as a three month rent holiday upon the 27 month extension starting May 2023. There were net additions of $544,000 related to the addition of new laboratory space in Planegg, Germany in February 2023. The leases do not provide an implicit rate and, due to the lack of a commercially salable product, the Company is generally considered unable to obtain commercial credit. Therefore, the Company estimated its incremental interest rate to be 6% for the original leases and 8% for the New York City extension and German laboratory, considering the quoted rates for the lowest investment-grade debt and the interest rates implicit in recent financing leases. Immunic used its estimated incremental borrowing rate and other information available at the lease commencement date in determining the present value of the lease payments. Immunic’s operating lease costs and variable lease costs were $257,000 and $195,000 for the three months ended March 31, 2024 and 2023, respectively. Variable lease costs consist primarily of common area maintenance costs, insurance and taxes which are paid based upon actual costs incurred by the lessor. Maturities of the operating lease obligation are as follows as of March 31, 2024 : 2024 $ 551,000 2025 433,000 2026 78,000 2027 82,000 2028 79,000 Thereafter — Total 1,223,000 Interest (93,000) Present value of obligation $ 1,130,000 Contractual Obligations As of March 31, 2024, the Company has non-cancelable contractual obligations under certain agreements related to its development programs vidofludimus calcium and IMU-856 totaling approximately $3.0 million, all of which is expected to be paid in 2024 and 2025. Other Commitments and Obligations Daiichi Sankyo Agreement On January 5, 2020, the Company exercised its option to obtain the exclusive worldwide right to commercialization of IMU-856. Among other things, the option exercise grants Immunic AG the rights to Daiichi Sankyo’s patent application related to IMU-856, for which the Company received a notice of allowance from the U.S. Patent & Trademark Office in August 2022. In connection with the option exercise, the Company paid a one-time upfront licensing fee to Daiichi Sankyo. Under the Daiichi Sankyo Agreement, Daiichi Sankyo is also eligible to receive future development, regulatory and sales milestone payments, as well as royalties related to IMU-856. Legal Proceedings The Company is not currently a party to any litigation, nor is it aware of any pending or threatened litigation, that it believes would materially affect its business, operating results, financial condition or cash flows. However, its industry is characterized by frequent claims and litigation including securities litigation, claims regarding patent and other intellectual property rights and claims for product liability. As a result, in the future, the Company may be involved in various legal proceedings from time to time.

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value	Fair Value The following fair value hierarchy tables present information about each major category of the Company’s financial assets and liabilities measured at fair value on a recurring basis (in thousands): Fair Value Measurement at March 31, 2024 Fair Value Level 1 Level 2 Level 3 Assets Money market funds $ 72,961 $ 72,961 $ — $ — Total assets at fair value 72,961 72,961 $ — $ — Fair Value Measurement at December 31, 2023 Fair Value Level 1 Level 2 Level 3 Assets Money market funds $ 34,087 $ 34,087 $ — $ — Total assets at fair value $ 34,087 $ 34,087 $ — $ — There were no transfers between Level 1, Level 2 or Level 3 assets during the periods presented. For the Company’s money market funds which are included as a component of cash and cash equivalents on the consolidated balance sheet, realized gains and losses are included in interest income (expense) on the consolidated statements of operations. Our money market fund account is held in our bank in the U.S. and was earning interest at a rate of 5.2% in a U.S. Government money market fund. The Company has cash balances in banks in excess of the maximum amount insured by the FDIC and other international agencies as of March 31, 2024. The Company has not historically experienced any credit losses with balances in excess of FDIC limits. The Company recorded tranche rights of $23.6 million at January 8, 2024 as a result of the January 2024 Financing (see note 6). The fair value measurement of the tranche rights associated with the January 2024 Financing was classified as Level 3 under the fair value hierarchy. The fair value of the the tranche rights was determined using a Black Scholes Option Pricing Model. The inputs to this model included a risk-free rate range of 3.93%-4.36%, a stock price volatility range of 105-115%, an expected dividend rate of —% and remaining term of 1.81-4.81 years. This liability was revalued on March 4, 2024, upon approval to increase its authorized shares of common stock from 130 million to 500 million, which resulted in the reclassification of the tranche rights from a liability to equity. This revaluation resulted in an increase in the tranche rights liability of $4.8 million using a Black Scholes Option Pricing Model. The inputs to this model as of the date of the reclassification included a risk-free rate range of 4.16%-4.63%, a stock price volatility range of 90-105%, an expected dividend rate of —% and remaining term of 1.66-4.66 years. The inputs used in the determination of fair value of the liability are level 3 inputs. A rollforward of the fair value of the tranche rights is as follows (in thousands): December 31, 2023 $ — Fair value as of January 8, 2024 $ 23,600 Change in fair value through March 4, 2024 $ 4,796 Reclassification to equity $ (28,396) March 31, 2024 $ —

Common Stock

Common Stock	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Common Stock	Common Stock Shelf Registration Statement In November 2023, we filed a shelf registration statement on Form S-3 (the "2023 Shelf Registration Statement"). The 2023 Shelf Registration Statement permits the offering, issuance and sale of up to $250.0 million of common stock, preferred stock, warrants, debt securities, and/or units in one or more offerings and in any combination of the foregoing. As of May 8, 2024, the 2023 Shelf Registration statement has not been declared effective by the SEC, however, the Company can (i) continue to sell, subject to applicable SEC requirements, unsold securities remaining on the expired 2020 Shelf Registration Statement until the 2023 Shelf Registration Statement has been declared effective (or May 22, 2024, if sooner); and (ii) after the 2023 Shelf Registration Statement has been declared effective, offer and sell additional securities registered on the new Form S-3, as well as unsold securities from the expired 2020 Shelf Registration Statement that are permitted by SEC rules to be included in the 2023 Shelf Registration Statement. In November 2020, the Company filed a shelf registration statement on Form S-3 (the "2020 Shelf Registration Statement"). The 2020 Shelf Registration Statement permitted the offering, issuance and sale of up to $250.0 million of common stock, preferred stock, warrants, debt securities, and/or units in one or more offerings and in any combination of the foregoing. The 2020 Shelf Registration Statement expired in November 2023 but, as explained above, unsold securities from this expired registration statement can continue to be sold under the 2023 Shelf Registration Statement. As of March 31, 2024, there is $75.0 million of unsold securities from this 2020 Shelf Registration Statement. In December 2020, the Company filed a Prospectus Supplement for the offering, issuance and sale of up to a maximum aggregate offering price of $50.0 million of common stock that may be issued and sold under an at-the-market sales agreement with SVB Leerink LLC (now Leerink Partners LLC) as agent ("December 2020 ATM"). The Company has used and intends to continue to use the net proceeds from the December 2020 ATM to continue to fund the ongoing clinical development of our product candidates and for other general corporate purposes, including funding existing and potential new clinical programs and product candidates. The December 2020 ATM will terminate upon the earlier of (i) the issuance and sale of all of the shares through Leerink Partners LLC on the terms and subject to the conditions set forth in the December 2020 ATM or (ii) termination of the December 2020 ATM as otherwise permitted thereby. The December 2020 ATM may be terminated at any time by either party upon ten days’ prior notice, or by Leerink Partners LLC at any time in certain circumstances, including the occurrence of a material adverse effect on us. As of March 31, 2024, $7.3 million in capacity remains under the December 2020 ATM. In May 2022, the Company filed a Prospectus Supplement to the 2020 Shelf Registration Statement for the offering, issuance and sale of up to a maximum aggregate offering price of $80.0 million of common stock that may be issued and sold under another at-the-market sales agreement ("May 2022 ATM") with Leerink Partners LLC (formerly SVB Leerink LLC) as agent. The Company intends to use the net proceeds from the offering to continue to fund the ongoing clinical development of its product candidates and for other general corporate purposes, including funding existing and potential new clinical programs and product candidates. The May 2022 ATM will terminate upon the earlier of (i) the issuance and sale of all of the shares through Leerink Partners LLC on the terms and subject to the conditions set forth in the May 2022 ATM or (ii) termination of the May 2022 ATM as otherwise permitted thereby. The May 2022 ATM may be terminated at any time by either party upon ten days’ prior notice, or by Leerink Partners LLC at any time in certain circumstances, including the occurrence of a material adverse effect on the Company. As of March 31, 2024, $80.0 million in capacity remains under the May 2022 ATM. The Company has agreed to pay Leerink Partners LLC a commission equal to 3.0% of the gross proceeds from the sales of common shares pursuant to both ATM's and has agreed to provide Leerink Partners LLC with customary indemnification and contribution rights. For the three months ended March 31, 2024, we raised gross proceeds of $0.2 million pursuant to the December 2020 ATM through the sale of 150,000 shares of common stock at a weighted average price of $1.31 per share. The net proceeds from the December 2020 ATM were $0.2 million after deducting sales agent commissions of $6,000. The Company did not have any ATM activity during the three months ended March 31, 2023. Equity Offerings Private Placement of up to $240 million ("The January 2024 Financing") On January 4, 2024, Immunic entered into a Securities Purchase Agreement with select accredited investors, pursuant to which the Company agreed to issue and sell to the Investors in a three-tranche private placement shares of the Company’s common stock, $0.0001 par value per share or in lieu thereof, pre-funded warrants to purchase shares of Common Stock. The Pre-Funded Warrants are exercisable immediately for $0.0001 per share and until exercised in full. • The first tranche, which closed on January 8, 2024, resulted in the purchase by the Investors of an aggregate of $80 million of Common Stock (or pre-funded warrants) from the Company at a price of $1.43 per share; • The second tranche is a conditional mandatory purchase by the Investors of an additional $80 million of Common Stock (or pre-funded warrants) from the Company at a price of $1.716 per share, equal to 120% of the price paid in the first tranche and is subject to the satisfaction of three conditions: ◦ release by the Company of topline data from its Phase 2b clinical trial of vidofludimus calcium (IMU-838) in progressive multiple sclerosis, which data is currently expected in or around April 2025; ◦ the 10-day volume-weighted average price of the Common Stock is at least $8.00 per share during the 6 months following the data release; and ◦ aggregate trading volume during the same 10-day period is at least $100 million. • The third tranche must occur no later than three years after the second tranche and is conditioned on the same volume-weighted average share price and minimum trading volumes as the second tranche. The third tranche provides for the issuance of $80 million of shares of common stock (or pre-funded warrants) at the same price per share as the second tranche, but permits investors to fund their purchase obligations on a “cashless” or net settlement basis, which would reduce the cash proceeds to be raised by the Company in the Private Placement. Any of the conditions in the second or third tranches can be waived by holders of a majority of the outstanding securities (including the lead investor). The Private Placement resulted in gross proceeds to the Company of approximately $80 million in the first tranche, and an additional $80 million if and when the second tranche occurs. If the second tranche is completed and conditions for the third tranche are satisfied or waived, the Company could receive up to an additional $80 million in the third tranche. As of the closing date of the transaction of January 8, 2024, the Company did not have enough authorized shares to be able to issue the potential shares for tranche 2 and tranche 3 (collectively referred to hereafter as "the tranche rights"). Therefore, the Company recorded the value associated to the tranche rights as a liability of $23.6 million and allocated the remainder of the $80 million received (or $56.4 million) with the common stock and pre-funded warrants to equity. On March 4, 2024, the stockholders voted to increase the Company's authorized common shares from 130 million to 500 million shares. As a result of the ability to issue shares in satisfaction of the tranche rights, the instrument was reclassified to stockholders' equity. The Company allocated the transaction cost across the instruments on a relative fair value basis at the grant date. As a result $4.0 million was netted against the equity proceeds and $1.7 million was recorded in other expense in the Consolidated Statements of Operation for the three months ended March 31, 2024. The Company registered for resale by the investors in the January 2024 Financing up to 55,944,850 shares of common stock issued (or issuable upon exercise of pre-funded warrants) in the first tranche. The Company will not receive any proceeds from the sale of these shares of common stock. These shares are registered on a registration statement on Form S-3 (registration No. 333-277040), which was declared effective by the SEC on April 30, 2024. Common Stock On March 4, 2024, the stockholders of the Company voted to increase the authorized shares of the Company from 130,000,000 shares of common stock to 500,000,000 shares of common stock, par value of $0.0001 per share. The voting, dividend and liquidation rights of the holders of the Company’s common stock are subject to and qualified by the rights, powers and preferences of any holders of preferred stock. Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to receive dividends, as may be declared by the Board of Directors, if any. Through March 31, 2024, no cash dividends had been declared or paid. Pre-funded Warrants The Company issued 11,193,564 pre-funded warrants in connection with the January 2024 Financing, which all remain outstanding as of March 31, 2024. Preferred Stock The Company’s certificate of incorporation, as amended and restated, authorizes the Company to issue 20 million shares of $0.0001 par value preferred stock, rights and preferences to be set by the Board of Directors. No preferred shares were issued or outstanding as of March 31, 2024. Stock Reserved for Future Issuance Shares reserved for future issuance at March 31, 2024 are as follows: Number of Common stock reserved for issuance for: 2021 Employee stock purchase plan 1,000,011 Pre-funded stock warrants 11,193,564 Outstanding stock options 10,318,323 Shares reserved for tranche 2 rights 46,620,046 Maximum shares reserved for tranche 3 rights 46,620,046 Common stock options available for future grant: 2014 Equity Incentive Plan 43,311 2017 Inducement Equity Incentive Plan 46,250 2019 Omnibus Equity Incentive Plan 9,131,506 Total common shares reserved for future issuance 124,973,057

Stock-Based Compensation Plans

Stock-Based Compensation Plans	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation Plans	Stock-Based Compensation Plans 2021 Employee Stock Purchase Plan On April 25, 2021, the Company adopted the 2021 Employee Stock Purchase Plan ("ESPP"), which was approved by stockholder vote at the 2021 Annual Meeting of Stockholders held on June 10, 2021. The ESPP provides eligible employees of the Company with an opportunity to purchase common stock of the Company through accumulated payroll deductions, which are included in other current liabilities until they are used to purchase Company shares. Eligible employees participating in the bi-annual offering period can choose to have up to the lesser of 15% of their annual base earnings or the IRS annual share purchase limit of $25,000 in aggregate market value to purchase shares of the Company’s common stock. The purchase price of the stock is the lesser of (i) 85% of the closing market price on the date of purchase and (ii) the closing market price at the beginning of the bi-annual offering period. The maximum number of shares initially reserved for delivery under the plan was 200,000 shares. This maximum number was increased by 1 million shares through approval by stockholders of the Company at the Company's Special Meeting of stockholders held on March 4, 2024. The first enrollment period under the plan commenced on August 1, 2021 and the Company has issued 199,989 shares life-to-date under the ESPP. The Company recognized $0 and $46,000 of expense related to the plan during the three months ended March 31, 2024 and 2023, respectively. Stock Option Programs In July 2019, the Company’s stockholders approved the 2019 Omnibus Equity Incentive Plan, as amended on June 28, 2023 (the “2019 Plan”), which was adopted by the Board of Directors (the "Board") with an effective date of June 14, 2019. The 2019 Plan allows for the grant of equity awards to employees, consultants and non-employee directors. An initial maximum of 1,500,000 shares of the Company’s common stock were available for grant under the 2019 Plan. The 2019 Plan included an evergreen provision that allowed for the annual addition of up to 4% of the Company’s fully-diluted outstanding stock, with a maximum allowable increase of 4,900,000 shares over the term of the 2019 Plan. In accordance with this provision, the shares available for grant were increased in 2020 through 2023 by a total of 4,408,871 shares. At the Company's Annual Stockholders meeting on June 28, 2023, stockholders voted to increase the allowable shares under the 2019 plan by 4,440,000 shares as well as to eliminate the evergreen provision. On March 4, 2024, the stockholders voted at the Company's Special Meeting to increase the allowable shares under the 2019 plan by 9,100,000. The 2019 Plan is currently administered by the Board, or, at the discretion of the Board, by a committee of the Board, which determines the exercise prices, vesting schedules and other restrictions of awards under the 2019 Plan at its discretion. Options to purchase stock may not have an exercise price that is less than the fair market value of underlying shares on the date of grant, and may not have a term greater than ten years. Incentive stock options granted to employees typically vest over four years. Non-statutory options granted to employees, officers, members of the Board, advisors, and consultants of the Company typically vest over three Shares that are expired, terminated, surrendered or canceled under the 2019 Plan without having been fully exercised will be available for future awards. Stock Option Repricing On March 4, 2024, the Company's stockholders voted to approve the repricing of outstanding stock options having an exercise price above $3.00 per share to $1.72 per share. All other terms of the grant remained the same. There were 3,317,596 stock options that were repriced to $1.72 per share. The repricing will result in an addition $1.2 million of stock compensation being recognized by the Company over the remaining term of the repriced grants and $0.9 million of this amount recognized in the quarter ended March 31, 2024. Movements during the year The following table summarizes stock option activity for the quarters ended March 31, 2024 and 2023, respectively, for the 2019 Plan: Options Weighted- Weighted- Aggregate Outstanding as of January 1, 2024 6,196,140 $ 7.15 Granted 4,175,349 $ 1.21 Exercised — $ — Repricing Modification — $ 9.55 Forfeited or expired (53,166) $ 5.25 Outstanding as of March 31, 2024 10,318,323 $ 1.68 8.64 $ 462,223 Options vested and expected to vest as of March 31, 2024 10,318,323 $ 1.68 8.64 $ 462,223 Options exercisable as of March 31, 2024 3,224,039 $ 2.21 7.23 $ 5,500 Options Weighted- Weighted- Aggregate Outstanding as of January 1, 2023 3,791,688 $ 11.33 Granted 1,815,314 $ 1.41 Exercised — $ — Forfeited or expired (11,161) $ 13.29 Outstanding as of March 31, 2023 5,595,841 $ 8.11 8.66 $ 161,428 Options vested and expected to vest as of March 31, 2023 5,595,841 $ 8.11 8.66 $ 161,428 Options exercisable as of March 31, 2023 1,888,367 $ 12.66 7.67 $ 1,980 Measurement The weighted-average assumptions used in the BSM option pricing model to determine the fair value of the employee and non-employee stock option grants relating to the 2019 Plan were as follows: Risk-Free Interest Rate The risk-free rate assumption is based on U.S. Treasury instruments with maturities similar to the expected term of the stock options. Expected Dividend Yield The Company has not issued any dividends and does not expect to issue dividends over the life of the options. As a result, the Company has estimated the dividend yield to be zero. Expected Volatility Due to the Company’s limited operating history and a lack of company specific historical and implied volatility data, the Company estimates expected volatility based on the historical volatility of its own stock combined with a group of comparable companies that are publicly traded. The historical volatility data was computed using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the stock-based awards. Expected Term The expected term of options is estimated considering the vesting period at the grant date, the life of the option and the average length of time similar grants have remained outstanding in the past. The weighted-average grant date fair value of stock options granted under the 2019 Plan (excluding the repriced stock options) during the three months ended March 31, 2024 and 2023 was $0.97 and $1.15, respectively. The weighted average grant date fair value of the repriced stock options was $1.22. The following are the underlying assumptions used in the Black-Scholes option pricing model to determine the fair value of stock options granted to employees and to non-employees under this stock plan: Three Months Ended March 31, 2024 2023 Risk-free interest rate 4.05% 3.97% Expected dividend yield 0% 0% Expected volatility 100.0% 102.0% Expected term of options (years) 6.02 6.02 Stock-Based Compensation Expense Total stock-based compensation expense for all stock awards recognized in the accompanying unaudited condensed consolidated statements of operations is as follows: Three Months 2024 2023 Research and development $ 1,163,000 $ 903,000 General and administrative 1,587,000 1,076,000 Total $ 2,750,000 $ 1,979,000 As of March 31, 2024, there was $13.5 million in total unrecognized compensation expense relating to the 2019 Plan, including $0.3 million related to repriced stock options, to be recognized over a weighted average period of 3.17 years. There was $0.6 million and $0.3 million of stock-based compensation expense during the three months ended March 31, 2024 related to the repricing included in general and administrative and research and development expense respectively. Summary of Equity Incentive Plans Assumed from Vital Therapies, Inc. On April 12, 2019, we assumed the equity incentive plans of Vital Therapies, Inc. (“Vital”) following an exchange transaction (the “Transaction”) with Immunic AG. In the Transaction, holders of ordinary shares of Immunic AG exchanged all of their shares for shares of our common stock, resulting in Immunic AG becoming our wholly owned subsidiary. Following the Transaction, we changed our name to Immunic, Inc. Upon completion of the Transaction with Vital on April 12, 2019, Vital’s 2012 Stock Option Plan (the “2012 Plan”), Vital’s 2014 Equity Incentive Plan (the “2014 Plan”) and Vital’s 2017 Inducement Equity Incentive Plan (the “Inducement Plan”), were assumed by the Company. All awards granted under these plans have either been forfeited or expired. There remain 43,311 shares available for grant under the 2014 Plan as of March 31, 2024. In September 2017, Vital’s board of directors approved the Inducement Plan, which was amended and restated in November 2017. Under the Inducement Plan 46,250 shares of Vital’s common stock were reserved to be used exclusively for non-qualified grants to individuals who were not previously employees or directors as an inducement material to a grantee's entry into employment within the meaning of Rule 5635(c)(4) of the Nasdaq Listing Rules. No expense was recorded for the plans assumed from Vital during the three months ended March 31, 2024 and 2023, respectively.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2024
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Executive Chairman Agreement with Duane Nash On April 15, 2020, the compensation committee of the Board of Directors of the Company independently reviewed and approved entering into an employment agreement with the Executive Chairman of the Board, Duane Nash, MD, JD, MBA (the “Executive Chairman Agreement”) and pursuant to such approval, on April 17, 2020, the Company and Dr. Nash entered into the Executive Chairman Agreement. The Executive Chairman Agreement establishes an “at will” employment relationship. On December 28, 2022, the Company and Dr. Nash entered into Addendum No. Four, which extended the term of employment from December 31, 2022 to December 31, 2023 with a base salary of $30,250 per month. On October 17, 2023, Immunic, Inc. and Dr. Duane Nash entered into Addendum Number 5 to the Employment Agreement dated April 17, 2020, as amended as of October 15, 2020, April 15, 2021, March 15, 2022, and December 28, 2022, to extend the term of Dr. Nash’s employment as Executive Chairman of the Board of Directors of the Company to December 31, 2024. In connection with the Addendum, the Company increased Dr. Nash’s monthly base salary to $32,368 from $30,250 (which includes the cash retainer payable for serving on the Company’s Board or for acting as the Chairman of the Board). All other terms of the Executive Chairman Agreement remain the same.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying consolidated financial statements have been prepared in conformity with United States generally accepted accounting principles ("U.S. GAAP") and include the accounts of Immunic and its wholly-owned subsidiaries, Immunic AG and Immunic Australia Pty Ltd. All intercompany accounts and transactions have been eliminated in consolidation. Immunic manages its operations as a single reportable segment for the purposes of assessing performance and making operating decisions. Unaudited Interim Financial Information Immunic has prepared the accompanying interim unaudited condensed consolidated financial statements in accordance with United States generally accepted accounting principles, (“US GAAP”), for interim financial information and with the
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires the Company to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, expenses and the disclosure of contingent assets and liabilities in the Company’s consolidated financial statements. The most significant estimates in the Company’s financial statements and accompanying notes relate to clinical trial expenses and share-based compensation. Management believes its estimates to be reasonable under the circumstances. Actual results could differ materially from those estimates and assumptions.
Foreign Currency Translation and Presentation	Foreign Currency Translation and Presentation The Company’s reporting currency is United States (“U.S.”) dollars. Immunic AG is located in Germany with the euro being its functional currency. Immunic Australia Pty Ltd.’s functional currency is the Australian dollar. All amounts in the financial statements where the functional currency is not the U.S. dollar are translated into U.S. dollar equivalents at exchange rates as follows: • assets and liabilities at reporting period-end rates; • income statement accounts at average exchange rates for the reporting period; and • components of equity at historical rates. Gains and losses from translation of the financial statements into U.S. dollars are recorded in stockholders’ equity as a component of accumulated other comprehensive income (loss). Realized and unrealized gains and losses resulting from foreign currency transactions denominated in currencies other than the functional currency are reflected as general and administrative expenses in the Consolidated Statements of Operations. Foreign currency transaction gains and losses related to long-term intercompany loans that are payable in the foreseeable future are recorded in Other Income (Expense). The Consolidated Statements of Cash Flows were prepared by using the average exchange rate in effect during the reporting period which reasonably approximates the timing of the cash flows.
Cash and Cash Equivalents and Investments- other	Cash and Cash Equivalents and Investments- other The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Cash and cash equivalents consist of cash on hand and deposits in banks located in the U.S. of approximately $73.2 million, Germany of approximately $22.5 million and Australia of approximately $1.6 million as of March 31, 2024. The Company maintains cash and cash equivalent balances denominated in Euro and U.S. dollars with major financial institutions in the U.S. and Germany in excess of the deposit limits insured by the government. Management periodically reviews the credit standing of these financial institutions. The Company currently deposits its cash and cash equivalents with two large financial institutions. Cash and Cash equivalents in the U.S. are held at JP Morgan and are primarily held in a U.S. Government money market fund account earning interest at a rate of 5.2% during the period ended March 31, 2024. Cash and cash equivalents in Germany are earning interest at a rate of 3.5% to 3.75% during the period ended March 31, 2024.
Fair Value Measurement	Fair Value Measurement Fair value is defined as the price that would be received to sell an asset or be paid to transfer a liability in an orderly transaction between market participants on the measurement date. Accounting guidance establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value: Level 1—Quoted prices in active markets for identical assets or liabilities. Level 1 assets consisted of money market funds for the periods presented. The Company had no Level 1 liabilities for the periods presented. Level 2—Inputs other than observable quoted prices for the asset or liability, either directly or indirectly; these include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. The Company had no Level 2 assets or liabilities for the periods presented. Level 3—Unobservable inputs to the valuation methodology that are significant to the measurement of the fair value of assets or liabilities. The Company had no Level 3 assets or liabilities for the periods presented. The carrying value of cash and cash equivalents, other current assets and prepaid expenses, accounts payable, accrued expenses, and other current liabilities approximates fair value due to the short period of time to maturity.
Property and Equipment	Property and Equipment three
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets
Research and Development Expenses	Research and Development Expenses These costs primarily include external development expenses and internal personnel expenses for its development programs, vidofludimus calcium and IMU-856. Immunic has spent the majority of its research and development resources on vidofludimus calcium, the Company's lead development program, for clinical trials in MS and UC. Research and development expenses consist of expenses incurred in research and development activities, which include clinical trials, contract research services, certain milestone payments, salaries and related employee benefits, allocated facility costs and other outsourced services. Research and development expenses are charged to operations as incurred. The Company enters into agreements with contract research organizations (“CROs”) to provide clinical trial services for individual studies and projects by executing individual work orders governed by a Master Service Arrangement (“MSA”). The MSAs and associated work orders provide for regular recurrent payments and payments upon the completion of certain milestones. The Company regularly assesses the timing of payments against actual costs incurred to ensure a proper accrual of related expenses in the appropriate accounting period.
Collaboration Arrangements	Collaboration Arrangements Certain collaboration and license agreements may include payments to or from the Company of one or more of the following: non-refundable or partially refundable upfront or license fees; development, regulatory and commercial milestone payments; payment for manufacturing supply services; partial or complete reimbursement of research and development costs; and royalties on net sales of licensed products. The Company assesses whether such contracts are within the scope of Financial Accounting Standards Board (FASB) Accounting Standards Update (“ASU”) 2014-09 “ Revenue from Contracts with Customers ” and ASU No. 2018-18, “ Collaborative Arrangements” ("ASU 2018-18"). ASU 2018-18, clarifies that certain elements of collaborative arrangements could qualify as transactions with customers in the scope of ASC 606. In October 2018, the Company entered into an option and license agreement (the "Daiichi Sankyo Agreement") with Daiichi Sankyo Co., Ltd. ("Daiichi Sankyo") which granted the Company the right to license a group of compounds, designated by the Company as IMU-856, as a potential new oral treatment option for gastrointestinal diseases such as celiac disease, inflammatory bowel disease, irritable bowel syndrome with diarrhea and other barrier function associated diseases. During the option period, the Company performed agreed upon research and development activities for which it was reimbursed by Daiichi Sankyo up to a maximum agreed-upon limit. Such reimbursement was recorded as other income. There are no additional research and development reimbursements expected under this agreement. On January 5, 2020, the Company exercised its option to obtain the exclusive worldwide right to commercialization of IMU-856. Among other things, the option exercise grants Immunic AG the rights to Daiichi Sankyo’s patent application related to IMU-856, for which the Company received a notice of allowance from the U.S. Patent & Trademark Office in August 2022. In connection with the option exercise, the Company paid a one-time upfront licensing fee to Daiichi Sankyo. Under the Daiichi Sankyo Agreement, Daiichi Sankyo is also eligible to receive future development, regulatory and sales milestone payments, as well as royalties related to IMU-856.
Government assistance	Government assistance Government assistance relating to research and development performed by Immunic Australia is recorded as a component of other (income) expense. This government assistance is recognized at a rate of 43.5% of the qualified research and development expenditures which are incurred. We also receive government assistance from the German Government for reimbursement of research and development expenses up to one million Euros per year. We recognized $36,000 and $1.8 million of other income
General and Administrative Expenses	General and Administrative Expenses General and administrative expenses consist primarily of salaries and related costs for personnel in executive, finance, business development and other support functions. Other general and administrative expenses include, but are not limited to, stock-based compensation, insurance costs, professional fees for legal, accounting and tax services, consulting, related facility costs and travel.
Stock-Based Compensation	Stock-Based Compensation The Company measures the cost of employee and non-employee services received in exchange for equity awards based on the grant-date fair value of the award recognized generally as an expense (i) on a straight-line basis over the requisite service period for those awards whose vesting is based upon a service condition, and (ii) on an accelerated method for awards whose vesting is based upon a performance condition, but only to the extent it is probable that the performance condition will be met. Stock-based compensation is (i) estimated at the date of grant based on the award’s fair value for equity classified awards and (ii) final measurement date for liability classified awards. Forfeitures are recorded in the period in which they occur. The Company estimates the fair value of stock options using the Black-Scholes-Merton option-pricing model ("BSM"), which requires the use of estimates and subjective assumptions, including the risk-free interest rate, the fair value of the underlying common stock, the expected dividend yield of the Company’s common stock, the expected volatility of the price of the Company’s common stock, and the expected term of the option. These estimates involve inherent uncertainties and the application of management’s judgment. If factors change and different assumptions are used, the Company’s stock-based compensation expense could be materially different in the future.
Leases	Leases The Company leases office space and office equipment. The underlying lease agreements have lease terms of less than 12 months and up to 60 months. Leases with terms of 12 months or less at inception are not included in the operating lease right of use asset and operating lease liability. The Company has three existing leases for office and laboratory space. At inception of a lease agreement, the Company determines whether an agreement represents a lease and at commencement each lease agreement is assessed as to classification as an operating or financing lease. The Company's leases have been classified as operating leases and an operating lease right-of-use asset and an operating lease liability have been recorded on the Company’s balance sheet. A right-of-use lease asset represents the Company’s right to use the underlying asset for the lease term and the lease obligation represents its commitment to make the lease payments arising from the lease. Right-of-use lease assets and obligations are recognized at the commencement date based on the present value of remaining lease payments over the lease term. As the Company’s leases do not provide an implicit rate, the Company has used an estimated incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The right-of-use lease asset includes any lease payments made prior to commencement and excludes any lease incentives. The lease term used in estimating future lease payments may include options to extend when it is reasonably certain that the Company will exercise that option. Operating lease expense is recognized on a straight-line basis over the lease term, subject to any changes in the lease or changes in expectations regarding the lease term. Variable lease costs such as common area costs and property taxes are expensed as incurred. Leases with an initial term of twelve months or less are not recorded on the balance sheet.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. Accumulated other comprehensive income (loss) has been reflected as a separate component of stockholders’ equity in the accompanying Consolidated Balance Sheets and consists of foreign currency translation adjustments (net of tax).
Income Taxes	Income Taxes The Company is subject to corporate income tax laws and regulations in the U.S., Germany and Australia. Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require significant judgment in their application. The Company utilizes the asset and liability method of accounting for income taxes which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the audited consolidated financial statements. Deferred income tax assets and liabilities are determined based on the differences between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of changes in tax rates on deferred tax assets and liabilities is recognized in operations in the period that includes the enactment date. Deferred taxes are reduced by a valuation allowance when, in the opinion of management, it is more likely than not some portion or the entire deferred tax asset will not be realized. As of March 31, 2024 and 2023, respectively, the Company maintained a full valuation allowance against the balance of deferred tax assets. It is the Company’s policy to provide for uncertain tax positions and the related interest and penalties based upon management’s assessment of whether a tax benefit is more likely than not to be sustained upon examination by tax authorities. The Company recognizes interest and penalties accrued on any unrecognized tax benefits as a component of income tax expense. The Company is subject to U.S. federal, New York, California, Texas, German and Australian income taxes. The Company is subject to U.S. federal or state income tax examination by tax authorities for tax returns filed for the years 2003 and forward due to the carryforward of NOLs. Tax years 2019 through 2022 are subject to audit by German and Australian tax authorities. The Company is not currently under examination by any tax jurisdictions.
Warrants and Tranche Rights	Warrants and Tranche Rights The Company accounts for issued financial instruments either as a liability or equity in accordance with ASC 480-10, Accounting for Certain Financial Instruments with Characteristics of both Liabilities and Equity (“ASC 480-10”) or ASC 815-40, Accounting for Derivative Financial Instruments Indexed to, and Potentially Settled in, a Company’s Own Stock (“ASC 815-40”). Under ASC 480-10, financial instruments are considered a liability if they are mandatorily redeemable and they require settlement in cash, other assets, or a variable number of shares. If financial instruments do not meet liability classification under ASC 480-10, the Company considers the requirements of ASC 815-40 to determine whether the financial instruments should be classified as a liability or as equity. Under ASC 815-40, contracts that may require settlement for cash are liabilities, regardless of the probability of the occurrence of the triggering event. Liability-classified financial instruments are measured at fair value on the issuance date and at the end of each reporting period. Any change in the fair value of the financial instruments after the issuance date is recorded in the consolidated statements of operations as a gain or loss. If financial
Net Loss Per Share	Net Loss Per Share
Recently Issued and/or Adopted Accounting Standards	Recently Issued and/or Adopted Accounting Standards There are no recently issued accounting standards that would have a significant impact on the Company's consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Schedule of Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss per Share	Potentially dilutive securities, not included in the calculation of diluted net loss per share attributable to common stockholders because to do so would be anti-dilutive, are as follows: As of March 31, 2024 2023 Options to purchase common stock 10,318,323 5,595,841

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Other Current Assets and Prepaid Expenses	Other Current Assets and Prepaid Expense consist of (in thousands): March 31, 2024 December 31, 2023 Prepaid clinical and related costs $ 2,767 $ 2,314 VAT receivable 770 703 Australian research and development tax incentive 676 670 Research grant — 1,104 Other 1,090 1,069 Total $ 5,303 $ 5,860
Schedule of Accounts Payable and Accrued Expenses	Accounts Payable consist of (in thousands): March 31, 2024 December 31, 2023 Clinical costs $ 6,211 $ 4,726 Legal and audit costs 115 160 Other 441 213 Total $ 6,767 $ 5,099 Accrued Expenses consist of (in thousands): March 31, 2024 December 31, 2023 Accrued clinical and related costs $ 11,497 $ 16,863 Accrued legal and audit costs 234 216 Accrued compensation 610 1,460 Accrued other 78 125 Total $ 12,419 $ 18,664
Schedule of Other Current Liabilities	Other Current Liabilities consist of (in thousands): March 31, 2024 December 31, 2023 Lease liabilities $ 697 $ 695 Other 263 271 Total $ 960 $ 966

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Schedule of Maturities of Operating Lease Obligation	Maturities of the operating lease obligation are as follows as of March 31, 2024 : 2024 $ 551,000 2025 433,000 2026 78,000 2027 82,000 2028 79,000 Thereafter — Total 1,223,000 Interest (93,000) Present value of obligation $ 1,130,000

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Schedule of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following fair value hierarchy tables present information about each major category of the Company’s financial assets and liabilities measured at fair value on a recurring basis (in thousands): Fair Value Measurement at March 31, 2024 Fair Value Level 1 Level 2 Level 3 Assets Money market funds $ 72,961 $ 72,961 $ — $ — Total assets at fair value 72,961 72,961 $ — $ — Fair Value Measurement at December 31, 2023 Fair Value Level 1 Level 2 Level 3 Assets Money market funds $ 34,087 $ 34,087 $ — $ — Total assets at fair value $ 34,087 $ 34,087 $ — $ —
Schedule of Fair Value of Tranche Rights	A rollforward of the fair value of the tranche rights is as follows (in thousands): December 31, 2023 $ — Fair value as of January 8, 2024 $ 23,600 Change in fair value through March 4, 2024 $ 4,796 Reclassification to equity $ (28,396) March 31, 2024 $ —

Common Stock (Tables)

Common Stock (Tables)	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Schedule of Shares Reserved for Future Issuance	Shares reserved for future issuance at March 31, 2024 are as follows: Number of Common stock reserved for issuance for: 2021 Employee stock purchase plan 1,000,011 Pre-funded stock warrants 11,193,564 Outstanding stock options 10,318,323 Shares reserved for tranche 2 rights 46,620,046 Maximum shares reserved for tranche 3 rights 46,620,046 Common stock options available for future grant: 2014 Equity Incentive Plan 43,311 2017 Inducement Equity Incentive Plan 46,250 2019 Omnibus Equity Incentive Plan 9,131,506 Total common shares reserved for future issuance 124,973,057

Stock-Based Compensation Plans

Stock-Based Compensation Plans (Tables)	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
Schedule of Stock Option Activity	The following table summarizes stock option activity for the quarters ended March 31, 2024 and 2023, respectively, for the 2019 Plan: Options Weighted- Weighted- Aggregate Outstanding as of January 1, 2024 6,196,140 $ 7.15 Granted 4,175,349 $ 1.21 Exercised — $ — Repricing Modification — $ 9.55 Forfeited or expired (53,166) $ 5.25 Outstanding as of March 31, 2024 10,318,323 $ 1.68 8.64 $ 462,223 Options vested and expected to vest as of March 31, 2024 10,318,323 $ 1.68 8.64 $ 462,223 Options exercisable as of March 31, 2024 3,224,039 $ 2.21 7.23 $ 5,500 Options Weighted- Weighted- Aggregate Outstanding as of January 1, 2023 3,791,688 $ 11.33 Granted 1,815,314 $ 1.41 Exercised — $ — Forfeited or expired (11,161) $ 13.29 Outstanding as of March 31, 2023 5,595,841 $ 8.11 8.66 $ 161,428 Options vested and expected to vest as of March 31, 2023 5,595,841 $ 8.11 8.66 $ 161,428 Options exercisable as of March 31, 2023 1,888,367 $ 12.66 7.67 $ 1,980
Schedule of Valuation Assumptions Used	The following are the underlying assumptions used in the Black-Scholes option pricing model to determine the fair value of stock options granted to employees and to non-employees under this stock plan: Three Months Ended March 31, 2024 2023 Risk-free interest rate 4.05% 3.97% Expected dividend yield 0% 0% Expected volatility 100.0% 102.0% Expected term of options (years) 6.02 6.02
Schedule of Stock-based Compensation Expense for Stock Awards Recognized	Total stock-based compensation expense for all stock awards recognized in the accompanying unaudited condensed consolidated statements of operations is as follows: Three Months 2024 2023 Research and development $ 1,163,000 $ 903,000 General and administrative 1,587,000 1,076,000 Total $ 2,750,000 $ 1,979,000

Description of Business and B_2

Description of Business and Basis of Financial Statements (Details) $ in Thousands	99 Months Ended
	Mar. 31, 2024 USD ($) lease	May 01, 2024 employee	Dec. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Subsequent Event [Line Items]
Number of development programs | lease	3
Accumulated deficit	$ (440,476)		$ (410,892)
Proceeds from issuance of private placement	430,900
Cash, cash equivalents and restricted cash	$ 97,312		$ 46,674	$ 92,761	$ 106,745
Subsequent Event
Subsequent Event [Line Items]
Number of employees | employee		80

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) € in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) lease financialInstitution shares	Mar. 31, 2023 USD ($)	Mar. 31, 2024 EUR (€) lease financialInstitution shares	Dec. 31, 2023 USD ($)
Property, Plant and Equipment [Line Items]
Cash and cash equivalents	$ 97,312,000			$ 46,674,000
Number of financial institutions used for cash deposits | financialInstitution	2		2
Depreciation expense	$ 26,000	$ 32,000
Impairment losses	0	0
Australian research and development tax incentive	676,000			$ 670,000
Government assistance, amount	$ 36,000	$ 1,800,000
Government Assistance, Statement of Income or Comprehensive Income [Extensible Enumeration]	Nonoperating Income (Expense)	Nonoperating Income (Expense)
Number of existing operating leases | lease	3		3
Pre-funded stock warrants
Property, Plant and Equipment [Line Items]
Warrant exercised (in shares) | shares	11,193,564		11,193,564
United States
Property, Plant and Equipment [Line Items]
Cash and cash equivalents	$ 73,200,000
Investment interest rate	5.20%		5.20%
United States | Money market funds
Property, Plant and Equipment [Line Items]
Investment interest rate	5.20%		5.20%
Germany
Property, Plant and Equipment [Line Items]
Cash and cash equivalents	$ 22,500,000
Australian research and development tax incentive | €			€ 1
Australia
Property, Plant and Equipment [Line Items]
Cash and cash equivalents	$ 1,600,000
Government R&D assistance rate	43.50%
Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	13 years		13 years
Lease term (in months)	60 months		60 months
Maximum | Germany | Money market funds
Property, Plant and Equipment [Line Items]
Investment interest rate	3.75%		3.75%
Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	3 years		3 years
Lease term (in months)	12 months		12 months
Minimum | Germany | Money market funds
Property, Plant and Equipment [Line Items]
Investment interest rate	3.50%		3.50%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss per Share (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Options to purchase common stock (in shares)	10,318,323	5,595,841

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Other Current Assets and Prepaid Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid clinical and related costs	$ 2,767	$ 2,314
VAT receivable	770	703
Australian research and development tax incentive	676	670
Research grant	0	1,104
Other	1,090	1,069
Total	$ 5,303	$ 5,860

Balance Sheet Details - Sched_2

Balance Sheet Details - Schedule of Accounts Payable (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Clinical costs	$ 6,211	$ 4,726
Legal and audit costs	115	160
Other	441	213
Total	$ 6,767	$ 5,099

Balance Sheet Details - Sched_3

Balance Sheet Details - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued clinical and related costs	$ 11,497	$ 16,863
Accrued legal and audit costs	234	216
Accrued compensation	610	1,460
Accrued other	78	125
Total	$ 12,419	$ 18,664

Balance Sheet Details - Sched_4

Balance Sheet Details - Schedule of Other Current Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Lease liabilities	$ 697	$ 695
Other	263	271
Total	$ 960	$ 966
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total	Total

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Loss Contingencies [Line Items]
Operating and variable lease cost	$ 257	$ 195
Contractual obligation	$ 3,000
Grafelfing, Germany
Loss Contingencies [Line Items]
Lease term (in years)	5 years
New York City
Loss Contingencies [Line Items]
Renewal option period (in months)	27 months
Rent holiday period	6 months
Lessee, operating lease, extended rent holiday period	3 months
Incremental borrowing rate on operating leases	6%
Planegg, Germany
Loss Contingencies [Line Items]
Increase in operating lease, right-of-use asset	$ 544
Incremental borrowing rate on operating leases	8%

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Maturities of Operating Lease Obligation (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2024	$ 551
2025	433
2026	78
2027	82
2028	79
Thereafter	0
Total	1,223
Interest	(93)
Present value of obligation	$ 1,130

Fair Value - Schedule of Financ

Fair Value - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Assets
Total assets at fair value	$ 72,961	$ 34,087
Level 1
Assets
Total assets at fair value	72,961	34,087
Level 2
Assets
Total assets at fair value	0	0
Level 3
Assets
Total assets at fair value	0	0
Money market funds
Assets
Total assets at fair value	72,961	34,087
Money market funds | Level 1
Assets
Total assets at fair value	72,961	34,087
Money market funds | Level 2
Assets
Total assets at fair value	0	0
Money market funds | Level 3
Assets
Total assets at fair value	$ 0	$ 0

Fair Value - Schedule of Fair V

Fair Value - Schedule of Fair Value of Tranche Rights (Details)	3 Months Ended
	Mar. 31, 2024 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
December 31, 2023	$ 0
Fair value as of January 8, 2024	23,600
Change in fair value through March 4, 2024	4,796
Reclassification to equity	(28,396)
March 31, 2024	$ 0

Fair Value - Additional Informa

Fair Value - Additional Information (Detail) - USD ($) $ in Millions			3 Months Ended
	Mar. 04, 2024	Jan. 08, 2024	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Tranche right, fair value		$ 23.6
Expected dividend yield	0%	0%	0%
Common stock, shares authorized (in shares)	500,000,000	130,000,000	500,000,000	130,000,000
Reclassification of future tranche right liability upon settlement	$ 4.8
Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Risk-free interest rate	4.16%	3.93%
Expected volatility	90%	105%
Expected term of options (years)	1 year 7 months 28 days	1 year 9 months 21 days
Common stock, shares authorized (in shares)	130,000,000
Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Risk-free interest rate	4.63%	4.36%
Expected volatility	105%	115%
Expected term of options (years)	4 years 7 months 28 days	4 years 9 months 21 days
Common stock, shares authorized (in shares)	500,000,000
United States
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment interest rate			5.20%

Common Stock - Shelf Registrati

Common Stock - Shelf Registration Statement (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) d $ / shares shares	Mar. 31, 2023 USD ($)	May 31, 2022 USD ($)	Dec. 31, 2020 USD ($)
Class of Stock [Line Items]
Commission, percent of gross proceeds from sale of common stock	3%
Proceeds from issuance of common stock	$ 191	$ 0
December 2020 ATM
Class of Stock [Line Items]
Maximum aggregate offering price of common stock, preferred stock, warrants, debt securities, and/or units				$ 50,000
Shelf registration, termination, prior written notice, number of days | d	10
Sale of stock, remaining capacity	$ 7,300
Shares issued	$ 200
Stock issued (in shares) | shares	150,000
Issuance of stock (in USD per share) | $ / shares	$ 1.31
Proceeds from issuance of common stock	$ 200
Underwriter commissions	$ 6
May 2022 ATM
Class of Stock [Line Items]
Maximum aggregate offering price of common stock, preferred stock, warrants, debt securities, and/or units			$ 80,000
Shelf registration, termination, prior written notice, number of days | d	10
Sale of stock, remaining capacity	$ 80,000

Common Stock - Equity Offering

Common Stock - Equity Offering (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		99 Months Ended
	Jan. 08, 2024	Jan. 04, 2024	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 04, 2024	Mar. 03, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Proceeds from issuance of private placement					$ 430,900
Reclassification of future tranche right liability upon settlement						$ 4,800
Common stock, shares authorized (in shares)	130,000,000		500,000,000		500,000,000	500,000,000		130,000,000
Change in fair value of the tranche rights			$ 4,796	$ 0
Equity
Class of Stock [Line Items]
Change in fair value of the tranche rights			4,000
Other Nonoperating Income (Expense)
Class of Stock [Line Items]
Change in fair value of the tranche rights			$ 1,700
Minimum
Class of Stock [Line Items]
Common stock, shares authorized (in shares)						130,000,000
Maximum
Class of Stock [Line Items]
Common stock, shares authorized (in shares)						500,000,000
Common Stock | Common Stock
Class of Stock [Line Items]
Reclassification of future tranche right liability upon settlement	$ 23,600
Common stock, shares authorized (in shares)						500,000,000	130,000,000
Private Placement | Common Stock
Class of Stock [Line Items]
Sale of stock, price per share (in USD per share)		$ 0.0001
Private Placement | Common Stock | Share-Based Payment Arrangement, Tranche One
Class of Stock [Line Items]
Proceeds from issuance of private placement	$ 80,000
Private Placement | Common Stock | Tranche 2
Class of Stock [Line Items]
Proceeds from issuance of private placement		$ 80,000
Private Placement | Common Stock | Tranche 3
Class of Stock [Line Items]
Proceeds from issuance of private placement		$ 80,000
Private Placement | Pre-funded stock warrants
Class of Stock [Line Items]
Sale of stock, price per share (in USD per share)		$ 0.0001
Private Placement | Accredited Investors
Class of Stock [Line Items]
Proceeds from issuance of private placement		$ 240,000
Private Placement | Accredited Investors | Common Stock | Share-Based Payment Arrangement, Tranche One
Class of Stock [Line Items]
Sale of stock, price per share (in USD per share)	$ 1.43
Consideration received on transaction	$ 80,000
Number of shares registered for resale	55,944,850
Private Placement | Accredited Investors | Common Stock | Tranche 2
Class of Stock [Line Items]
Sale of stock, price per share (in USD per share)		$ 1.716
Consideration received on transaction		$ 80,000
Sale of stock, consideration received, percentage		120%
Threshold trading days for weighted average price calculation		10 days
Weighted average price (in USD per share)		$ 8
Threshold trading days for aggregate trading volume calculation		10 days
Aggregate trading volume of last 10 days		$ 100,000
Private Placement | Accredited Investors | Common Stock | Tranche 3
Class of Stock [Line Items]
Consideration received on transaction		$ 80,000
Third tranche close period after second tranche (in years)		3 years
Common Stock and Pre-funded Warrants | Common Stock and Pre-funded Warrants
Class of Stock [Line Items]
Tranche rights as a liability, remainder amount	$ 80,000
Tranche rights as a liability, received amount	$ 56,400

Common Stock - Common Stock (De

Common Stock - Common Stock (Details)	3 Months Ended
	Mar. 31, 2024 numberOfVote $ / shares shares	Mar. 04, 2024 $ / shares shares	Jan. 08, 2024 shares	Dec. 31, 2023 $ / shares shares
Class of Stock [Line Items]
Common stock, shares authorized (in shares) | shares	500,000,000	500,000,000	130,000,000	130,000,000
Common stock, par value (in USD per share) | $ / shares	$ 0.0001	$ 0.0001		$ 0.0001
Number of votes per each share of common stock | numberOfVote	1
Common stock, cash dividends declared (in USD per share) | $ / shares	$ 0
Common stock, cash dividends paid (in USD per share) | $ / shares	$ 0
Minimum
Class of Stock [Line Items]
Common stock, shares authorized (in shares) | shares		130,000,000
Maximum
Class of Stock [Line Items]
Common stock, shares authorized (in shares) | shares		500,000,000

Common Stock - Pre-funded Warra

Common Stock - Pre-funded Warrants (Details)	Mar. 31, 2024 shares
Pre-funded stock warrants
Class of Stock [Line Items]
Shares issued from exercise of pre-funded warrants (in shares)	11,193,564

Common Stock - Preferred Stock

Common Stock - Preferred Stock (Details) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Equity [Abstract]
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, par value (in USD per share)	$ 0.0001	$ 0.0001
Preferred stock, shares outstanding (in shares)	0	0

Common Stock - Schedule of Shar

Common Stock - Schedule of Shares Reserved for Future Issuance (Details)	Mar. 31, 2024 shares
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	124,973,057
Tranche 2
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	46,620,046
Tranche 3
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	46,620,046
Outstanding stock options
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	10,318,323
Outstanding stock options | 2021 Employee stock purchase plan
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	1,000,011
Pre-funded stock warrants
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	11,193,564
Common stock options available for future grant: | 2014 Equity Incentive Plan
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	43,311
Common stock options available for future grant: | 2017 Inducement Equity Incentive Plan
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	46,250
Common stock options available for future grant: | 2019 Omnibus Equity Incentive Plan
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	9,131,506

Stock-Based Compensation Plan_2

Stock-Based Compensation Plans - Additional Information (Details) - USD ($)						1 Months Ended		3 Months Ended		48 Months Ended
	Mar. 04, 2024	Jan. 08, 2024	Jun. 28, 2023	Aug. 01, 2021	Apr. 25, 2021	Sep. 30, 2023	Jul. 31, 2019	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options repriced (in shares)	3,317,596
Stock-based compensation, exercise price (in dollars per share)	$ 1.72
Share-based payment arrangement								$ 1,200,000
Recognized amount								$ 900,000
Expected dividend yield	0%	0%						0%
Weight average fair value repriced stock options (in USD per share)								$ 1.22
Stock based compensation expense related to stock options								$ 2,750,000	$ 1,979,000
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense								600,000
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense								300,000
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of options (years)	4 years 7 months 28 days	4 years 9 months 21 days
Exercise price of warrants (in USD per share)	$ 3
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of options (years)	1 year 7 months 28 days	1 year 9 months 21 days
Exercise price of warrants (in USD per share)	$ 1.72
2021 Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum annual contributions per employee (as a percent)					15%
Purchase price of the stock, at discount from market price at purchase date (as a percent)					85%
Shares available for grant (in shares)					200,000
Shares issued under the ESPP (in shares)				199,989
Share-based compensation expense								$ 0	$ 46,000
2021 Employee stock purchase plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized (in shares)						1,000,000
2019 Omnibus Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)							1,500,000
Expected term of options (years)								6 years 7 days	6 years 7 days
Expected dividend yield								0%	0%
Options granted in period, weighted-average grant date fair value (in USD per share)								$ 0.97	$ 1.15
Total unrecognized compensation expense								$ 13,500,000
Stock based compensation expense related to stock options								$ 300,000
Period over which compensation cost will be recognized, in years								3 years 2 months 1 day
2019 Omnibus Equity Incentive Plan | Incentive stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)								4 years
2019 Omnibus Equity Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of options (years)								10 years
2019 Omnibus Equity Incentive Plan | Maximum | Non-statutory options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)								4 years
2019 Omnibus Equity Incentive Plan | Minimum | Non-statutory options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)								3 years
2019 Omnibus Equity Incentive Plan, Evergreen Provision
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized (in shares)							4,900,000			4,408,871
Additional shares authorized, percent							4%
Increase in other share (in shares)	9,100,000		4,440,000
2014 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)								43,311
2017 Inducement Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)											46,250
Share-based compensation expense								$ 0	$ 0

Stock-Based Compensation Plan_3

Stock-Based Compensation Plans - Schedule of Stock Option Activity (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Options
Repricing Modification (in shares)	0
Weighted- Average Exercise Price
Repricing Modifications (usd per share)	$ 9.55
Outstanding stock options | 2019 Omnibus Equity Incentive Plan
Options
Outstanding, beginning balance (in shares)	6,196,140	3,791,688
Granted (in shares)	4,175,349	1,815,314
Exercised (in shares)	0	0
Forfeited or expired (in shares)	(53,166)	(11,161)
Outstanding, ending balance (in shares)	10,318,323	5,595,841
Options vested and expected to vest, Ending balance (in shares)	10,318,323	5,595,841
Options exercisable, Ending balance (in shares)	3,224,039	1,888,367
Weighted- Average Exercise Price
Outstanding, beginning balance (usd per share)	$ 7.15	$ 11.33
Granted (usd per share)	1.21	1.41
Exercised (usd per share)	0	0
Forfeited or expired (usd per share)	5.25	13.29
Outstanding, ending balance (usd per share)	1.68	8.11
Options vested and expected to vest, Weighted-Average Exercise Price, Ending balance (usd per share)	1.68	8.11
Options exercisable, Weighted-Average Exercise Price, Ending balance (usd per share)	$ 2.21	$ 12.66
Other Disclosures
Outstanding, Weighted-Average Remaining Contractual Term, Ending balance	8 years 7 months 20 days	8 years 7 months 28 days
Options vested and expected to vest , Weighted-Average Remaining Contractual Term, Ending balance	8 years 7 months 20 days	8 years 7 months 28 days
Options exercisable, Weighted-Average Remaining Contractual Term, Ending balance	7 years 2 months 23 days	7 years 8 months 1 day
Outstanding, Aggregate Intrinsic Value, Ending balance	$ 462,223	$ 161,428
Options vested and expected to vest , Aggregate Intrinsic Value, Ending balance	462,223	161,428
Options exercisable, Aggregate Intrinsic Value, Ending balance	$ 5,500	$ 1,980

Stock-Based Compensation Plan_4

Stock-Based Compensation Plans - Schedule of Valuation Assumptions Used (Detail)			3 Months Ended
	Mar. 04, 2024	Jan. 08, 2024	Mar. 31, 2024	Mar. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0%	0%	0%
2019 Omnibus Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate			4.05%	3.97%
Expected dividend yield			0%	0%
Expected volatility			100%	102%
Expected term of options (years)			6 years 7 days	6 years 7 days

Stock-Based Compensation Plan_5

Stock-Based Compensation Plans - Schedule of Stock-based Compensation Expense for Stock Awards Recognized (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 2,750	$ 1,979
Employees
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	2,750	1,979
Employees | Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	1,163	903
Employees | General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 1,587	$ 1,076

Related Party Transactions (Det

Related Party Transactions (Details) - Duane Nash, MD, JD, MBA - Executive Chairman Agreement - Board of Directors Chairman - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
Salary and Wage, Officer, Monthly Base Salary		$ 30,250
Forecast
Related Party Transaction [Line Items]
Salary and Wage, Officer, Monthly Base Salary	$ 32,368