Delcath Systems (DCTH) 10-K 26 Mar 24 2023 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2023	Mar. 18, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-16133
Entity Registrant Name	DELCATH SYSTEMS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	06-1245881
Entity Address, Address Line One	566 Queensbury Avenue
Entity Address, City or Town	Queensbury
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	12804
City Area Code	212
Local Phone Number	489-2100
Title of 12(b) Security	Common stock, $0.01 par value per share
Trading Symbol	DCTH
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 81,667,153
Entity Common Stock, Shares Outstanding		24,562,692
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE
Entity Central Index Key	0000872912
Document Fiscal Period Focus	FY
Amendment Flag	false
Document Fiscal Year Focus	2023

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2023
Audit Information [Abstract]
Auditor Firm ID	688
Auditor Name	Marcum LLP
Auditor Location	New York, NY

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 12,646	$ 7,671
Restricted cash	50	4,151
Short-term investments	19,808	0
Accounts receivable, net	241	366
Inventories	3,322	1,998
Prepaid expenses and other current assets	1,091	1,969
Total current assets	37,158	16,155
Property, plant and equipment, net	1,352	1,422
Right-of-use assets	103	285
Total assets	38,613	17,862
Current liabilities
Accounts payable	1,012	2,018
Accrued expenses	5,249	4,685
Lease liabilities, current	37	186
Loan payable, current	5,239	7,846
Convertible notes payable, current	4,911	0
Total current liabilities	16,448	14,735
Warrant Liability	5,548	0
Other liabilities, non-current	840	1,144
Loan payable, non-current	0	3,070
Convertible notes payable, non-current	0	4,772
Total liabilities	22,836	23,721
Commitments and contingencies (see note 15)
Stockholders’ equity (deficit)
Preferred stock, $.01 par value; 10,000,000 shares authorized; 24,819 and 11,357 shares issued and outstanding at December 31, 2023 and 2022, respectively	0	0
Common stock, $.01 par value; 80,000,000 shares authorized; 22,761,554 shares and 10,046,571 shares issued and outstanding at December 31, 2023 and 2022, respectively	228	100
Additional paid-in capital	520,576	451,608
Accumulated deficit	(505,162)	(457,484)
Accumulated other comprehensive income (loss)	135	(83)
Total stockholders’ equity (deficit)	15,777	(5,859)
Total liabilities and stockholders’ equity	$ 38,613	$ 17,862

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	24,819	11,357
Preferred stock, shares outstanding (in shares)	24,819	11,357
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	80,000,000	80,000,000
Common stock, shares issued (in shares)	22,761,554	10,046,571
Common stock, shares outstanding (in shares)	22,761,554	10,046,571

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Total revenues	$ 2,065	$ 2,719
Cost of goods sold	(635)	(686)
Gross profit	1,430	2,033
Operating expenses:
Research and development expenses	17,502	18,583
Selling, general and administrative expenses	22,110	17,303
Total operating expenses	39,612	35,886
Operating loss	(38,182)	(33,853)
Change in fair value of warrant liability	(7,998)	0
Interest expense, net	(1,439)	(2,685)
Other income (expense)	(59)	30
Net loss	(47,678)	(36,508)
Comprehensive (loss) income:
Unrealized gain on investments	157	0
Foreign currency translation adjustments	61	101
Total comprehensive loss	$ (47,460)	$ (36,407)
Common share data:
Basic loss per common share (in dollars per share)	$ (2.94)	$ (4.12)
Diluted loss per common share (in dollars per share)	$ (2.94)	$ (4.12)
Weighted average number of basic shares outstanding (in shares)	16,229,931	8,864,615
Weighted average number of diluted shares outstanding (in shares)	16,229,931	8,864,615
Product revenue
Total revenues	$ 2,065	$ 2,548
Other revenue
Total revenues	$ 0	$ 171

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Preferred Stock	Series F Preferred Stock	Stock options	Employee Stock	Preferred Stock	Preferred Stock Preferred Stock	Preferred Stock Series E	Preferred Stock Series F Preferred Stock	Common Stock	Common Stock Common Stock	Common Stock Series E	Common Stock Series F Preferred Stock	Additional Paid in Capital	Additional Paid in Capital Common Stock	Additional Paid in Capital Preferred Stock	Additional Paid in Capital Series F Preferred Stock	Additional Paid in Capital Stock options	Additional Paid in Capital Employee Stock	Accumulated Deficit	Accumulated Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2021							11,357				7,906,728
Beginning balance at Dec. 31, 2021	$ 11,952						$ 0				$ 79				$ 432,831						$ (420,976)	$ 18
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation expense for issuance of stock options					$ 7,941														$ 7,941
Private placement -issuance of common shares and prefunded warrants, net of expenses (in shares)											2,139,843
Private placement - issuance of common stock and prefunded warrants, net of expenses	10,857										$ 21				10,836
Net loss	(36,508)																				(36,508)
Foreign currency translation adjustments	101
Foreign currency translation adjustments	(101)																					(101)
Ending balance (in shares) at Dec. 31, 2022							11,357				10,046,571
Ending balance at Dec. 31, 2022	(5,859)						$ 0				$ 100				451,608						(457,484)	(83)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation expense for issuance of stock options					$ 8,090	$ 61													$ 8,090	$ 61
Stock issued during period, shares, new issues (in shares)								44,483				19,646
Stock issued during period, value, new issues		$ 56	$ 49,487									$ 1				$ 55	$ 49,487
Issuance of common stock with the employee stock purchase plan (in shares)											41,435
Issuance of common stock with the employee stock purchase plan	$ 123														123
Issuance of common stock related to stock option exercises (in shares)	819										819
Issuance of common stock related to stock option exercises	$ 4														4
Conversion of Preferred Shares to common stock (in shares)									(100)	(30,921)			10,000	12,073,145
Conversion of Preferred Shares to common stock				$ 11,270										$ 122				$ 11,148
Issuance of common stock with common stock warrant exercises (in shares)											569,938
Issuance of common stock with common stock warrant exercises	5										$ 5
Net loss	(47,678)																				(47,678)
Unrealized gain on investments	157																					157
Foreign currency translation adjustments	61																					61
Ending balance (in shares) at Dec. 31, 2023							24,819				22,761,554
Ending balance at Dec. 31, 2023	$ 15,777						$ 0				$ 228				$ 520,576						$ (505,162)	$ 135

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Deficit) (Parenthetical) - $ / shares	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Statement of Stockholders' Equity [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (47,678)	$ (36,508)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock option compensation expense	8,151	7,941
Depreciation expense	128	132
Warrant liability fair value adjustment	7,998	0
Non-cash lease expense	271	443
Amortization of debt discount	776	768
Interest expense accrued related to convertible notes	160	160
Amortization of premiums and discounts on marketable securities	(151)	0
Changes in assets and liabilities:
Prepaid expenses and other assets	1,029	774
Accounts receivable	125	(322)
Inventory	(1,324)	(587)
Accounts payable and accrued expenses	(199)	1,798
Other liabilities, non-current	(537)	621
Deferred revenue	0	(170)
Net cash used in operating activities	(31,251)	(24,950)
Cash flows from investing activities:
Purchases of investments	(19,651)	0
Sales and maturities of investments	0	0
Purchase of property, plant and equipment	(58)	(209)
Net cash used in investing activities	(19,709)	(209)
Cash flows from financing activities:
Net proceeds from private placement	22,960	10,857
Proceeds from the issuance of common stock relating to the employee stock purchase plan	123	0
Repayment of Debt	(6,313)	(714)
Proceeds from the exercise of warrants	35,004	0
Proceeds from the exercise of stock options	4	0
Net cash provided by financing activities	51,778	10,143
Foreign currency effects on cash	56	(115)
Net increase (decrease) in total cash	874	(15,131)
Total Cash, Cash Equivalents and Restricted Cash:
Beginning of period	11,822	26,953
End of period	12,696	11,822
Cash, Cash Equivalents and Restricted Cash consisted of the following:
Cash	12,646	7,671
Restricted Cash	50	4,151
Total	12,696	11,822
Cash paid during the periods for:
Interest expense	1,459	1,873
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Right of use assets obtained in exchange for lease obligations	84	86
Conversion of mezzanine equity to common shares	11,269	0
Conversion of mezzanine equity to preferred shares	$ 7,099	$ 0

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business The Company is an interventional oncology company focused on the treatment of primary and cancers metastatic to the liver. The Company’s lead product, the HEPZATO TM KIT (“HEPZATO” melphalan for Injection/Hepatic Delivery System), a drug/device combination product, was approved by the US Food and Drug Administration (the “FDA”) on August 14, 2023, indicated as a liver-directed treatment for adult patients with uveal melanoma with unresectable hepatic metastases affecting less than 50% of the liver and no extrahepatic disease, or extrahepatic disease limited to the bone, lymph nodes, subcutaneous tissues, or lung that is amenable to resection, or radiation. In Europe, the hepatic delivery system is a stand-alone medical device having the same device components as HEPZATO KIT, but without the melphalan hydrochloride and is approved for sale under the trade name CHEMOSAT Hepatic Delivery System for Melphalan, or CHEMOSAT, where it has been used at major medical centers to treat a wide range of cancers in the liver. The first commercial use of HEPZATO for the treatment of mUM occurred in January 2024. In the United States, HEPZATO is considered a combination drug and device product and is regulated as a drug by the FDA. Primary jurisdiction for regulation of HEPZATO has been assigned to the FDA’s Center for Drug Evaluation and Research. The FDA has granted Delcath six orphan drug designations (five for melphalan in the treatment of patients with ocular (uveal) melanoma, cutaneous melanoma, intrahepatic cholangiocarcinoma, hepatocellular carcinoma, and neuroendocrine tumor indications and one for doxorubicin in the treatment of patients with hepatocellular carcinoma). The Company has sufficient raw material and component constituent parts of HEPZATO KIT to meet the first year of its anticipated demand and it intends to manage supply chain risk through stockpiled inventory and contracting with multiple suppliers for critical components. On February 28, 2022, CHEMOSAT received Medical Device Regulation (MDR) certification under the European Medical Devices Regulation (EU) 2017/745, which may be considered by jurisdictions when evaluating reimbursement. As of March 1, 2022, the Company assumed direct responsibility for sales, marketing and distribution of CHEMOSAT in Europe. The Company’s clinical development program for HEPZATO was comprised of the FOCUS Clinical Trial for Patients with metastatic hepatic dominant Uveal Melanoma (the “FOCUS Trial”), a global registration clinical trial that investigated objective response rate in patients with metastatic uveal melanoma (“mUM”). The current focus of the Company’s clinical development program is to generate clinical data for CHEMOSAT and HEPZATO in patients with mUM, either as monotherapy or in combination with immunotherapy. The Company extects that this will support increased clinical adoption of and reimbursement for CHEMOSAT in Europe, and to support reimbursement in various jurisdictions, including the United States. In addition to HEPZATO’s use to treat mUM, the Company believes that HEPZATO has the potential to treat cancers in the liver, such as metastatic colorectal cancer, metastatic neuroendocrine tumors, metastatic breast cancer and intrahepatic cholangiocarcinoma, and plans to begin one or more studies of HEPZATO KIT to treat such conditions in 2024. The Company believes that those and similar disease states are areas of unmet medical needs that represent significant market opportunities. Risks and Uncertainties The Company is subject to risks common to companies in the biopharmaceutical industry including, but not limited to, the risks associated with developing product candidates and successfully launching and commercializing its drug/device combination products, the Company’s ability to obtain regulatory approval of its such produ cts in the United States and other geography markets, the uncertainty of the broad adoption of its approved products by physicians and consumers, and significant competition. In addition, high rates of inflation have resulted in the U.S. Federal Reserve raising interest rates. Increases in interest rates, especially if coupled with reduced government spending and volatility in financial markets, may further increase economic uncertainty and heighten these risks. Furthermore, if additional banks and financial institutions enter receivership or become insolvent in the future in response to financial conditions affecting the banking system and financial markets, the Company or its partners’ ability to access existing cash, cash equivalents and investments may be threatened and could have a material adverse effect on the Company’s business and financial condition, including the Company’s ability to access additional capital on favorable terms, or at all, which could in the future negatively affect the Company’s ability to pursue its business strategy. Liquidity and Going Concern On December 31, 2023, the Company had cash, cash equivalents and restricted cash totaling $12.7 million and short-term investments totaling $19.8 million, as compared to cash, cash equivalents and restricted cash totaling $11.8 million at December 31, 2022. During the twelve months ended December 31, 2023, the Company used $31.3 million of cash in its operating activities and $6.3 million for principal payments. The Company’s future results are subject to substantial risks and uncertainties. The Company has operated at a loss for its entire history and there can be no assurance that it will ever achieve or maintain profitability. The Company has historically funded its operations primarily with proceeds from sales of common stock, warrants and prefunded warrants for the purchase of common stock, sales of preferred stock, proceeds from the issuance of convertible debt and borrowings under loan and security agreements. If there is a substantial delay in the activation of sites approved to administer HEPZATO, the Company expects to need to raise additional capital under structures available to the Company, including debt and/or equity offerings, which may not be on favorable terms. In a substantially delayed site activation scenario, the Company would not have sufficient funds to meet its obligations within twelve months from the issuance date of these condensed consolidated financial statements. As such, there is uncertainty regarding the Company’s ability to maintain liquidity sufficient to operate its business effectively, which raises substantial doubt about the Company’s ability to continue as a going concern. Debt financing and equity financing, if available, may involve agreements that include covenants limiting or restricting the Company’s ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If the Company raises funds through collaborations, or other similar arrangements with third parties, it may have to relinquish valuable rights to its technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to the Company and/or may reduce the value of its common stock. If the Company is unable to raise additional funds through equity or debt financings when needed, it may be required to delay, limit, reduce or terminate its product development or future commercialization efforts or grant rights to develop and market its product candidates even if the Company would otherwise prefer to develop and market such product candidates itself. The Company also expects to use cash and cash equivalents to fund activities relating to commercial support for HEPZATO, CHEMOSAT and any future clinical research trials and operating activities. The Company’s future liquidity and capital requirements will depend on numerous factors, including the initiation and progress of clinical trials and research and product development programs; obtaining regulatory approvals and complying with applicable laws and regulations; the timing and effectiveness of product commercialization activities, including marketing arrangements; the timing and costs involved in preparing, filing, prosecuting, defending and enforcing intellectual property rights; and the effect of competing technological and market developments. The Company’s capital commitments over the next twelve months include (a) $6.3 million to satisfy accounts payable, accrued expenses, current lease liabilities and current medac settlement and (b) $10.6 million of loan and convertible note principal payments, if the holders do not elect to convert up to $5.0 million of the notes into equity. Additional capital commitments beyond the next twelve months include (a) less than $0.1 million of lease liabilities; and (b) $0.8 million for settlement of litigation with medac.

Basis of Consolidated Financial

Basis of Consolidated Financial Statement Presentation	12 Months Ended
	Dec. 31, 2023
Basis Of Condensed Consolidated Financial Statement Presentation [Abstract]
Basis of Consolidated Financial Statement Presentation	Basis of Consolidated Financial Statement Presentation The accounting and financial reporting policies of the Company conform to generally accepted accounting principles in the United States of America (“GAAP”). The preparation of consolidated financial statements in conformity with GAAP requires management to make assumptions and estimates that impact the amounts reported in the Company’s consolidated financial statements. The consolidated financial statements include the accounts of all entities controlled by the Company. All significant inter-company accounts and transactions are eliminated.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Use of Estimates The Company bases its estimates and judgments on historical experience and on various other assumptions that it believes are reasonable under the circumstances. The amounts of assets and liabilities reported in the Company’s consolidated balance sheets and the amount of revenues and expenses reported for each of the periods presented are affected by estimates and assumptions, which are used for, but not limited to, the accounting for valuation of warrants, stock-based compensation, valuation of inventory, impairment of long-lived assets, income taxes and operating expense accruals. Such assumptions and estimates are subject to change in the future as additional information becomes available or as circumstances are modified. Actual results could differ from these estimates. Cash Equivalents and Concentrations of Credit Risk The Company considers investments with original maturities of three months or less at date of acquisition to be cash equivalents. The Company has deposits that exceed amounts insured by the Federal Deposit Insurance Corporation; however, the Company does not consider this a significant concentration of credit risk based on the strength of the financial institution. Restricted Cash Cash and cash equivalents that are restricted as to withdrawal or use under the terms of certain contractual agreements are recorded as restricted cash on the accompanying consolidated balance sheets. Investments Investments classified as short-term have maturities of less than one year. Investments classified as long-term are those that: (i) have a maturity of greater than one year, and (ii) the Company does not intend to liquidate within the next twelve months, although these funds are available for use and, therefore, are classified as available-for-sale. The Company’s investment strategy is to buy short-duration Treasury bills (T-bills). As of December 31, 2023, all investments held by the Company had remaining contractual maturities of less than five months. Accounts Receivable Accounts receivable, principally trade, are generally due within 30 days and are stated at amounts due from customers. Collections and payments from customers are monitored and a provision for estimated credit losses may be created based upon historical experience and specific customer collection issues that may be identified. Inventories Inventories are valued at the lower of cost or net realizable value (“NRV”) using the first-in, first-out method. The reported “NRV” of inventory includes finished saleable products, work-in-process, and raw materials that will be sold or used in future periods. The Company reserves for expired, obsolete, and slow-moving inventory. Property, Plant and Equipment Property, plant, and equipment are recorded at cost, less accumulated depreciation. The Company provides for depreciation on a straight-line basis over the estimated useful lives of the assets which range from three years. Leasehold improvements will be amortized over the shorter of the lease term or the estimated useful life of the related assets when they are placed into service. The Company evaluates property, plant and equipment for impairment periodically to determine if changes in circumstances or the occurrence of events suggest the carrying value of the asset or asset group may not be recoverable. Maintenance and repairs are charged to operations as incurred. Expenditures which substantially increase the useful lives of the related assets are capitalized. Leases The Company determines if an arrangement is a lease at inception, in accordance with Accounting Standards Codification (“ASC”) Topic 842, Leases. All operating lease commitments with a lease term greater than 12 months are recognized as right-of-use assets and lease liabilities, on a discounted basis on the balance sheet. Leases with an initial term of 12 months or less are not recorded on the balance sheet. Certain of the Company’s lease agreements include lease payments that are adjusted periodically for an index or rate. The leases are initially measured using the present value of the projected payments adjusted for the index or rate in effect at the commencement date. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance and other expenses, which do not transfer a good or service to the Company and are generally referred to as non-lease components. Variable non-lease components are not measured as part of the right-of-use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and are recognized as part of a right-of-use asset and liability. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. The Company may have options to renew lease terms for facilities and other assets. Some leases contain clauses for renewal at the Company’s option with renewal terms that generally extend the lease term from 1 to 5 years. The exercise of lease renewal options is generally at the Company’s sole discretion. The Company evaluates renewal and termination options at the lease commencement date to determine if it is reasonably certain to exercise the option on the basis of economic factors. Fair Value Measurements The Company adheres to ASC 820, Fair Value Measurement, which defines fair value, establishes a framework for measuring fair value, and expands disclosures about fair value measurements. ASC 820 applies to reported balances that are required or permitted to be measured at fair value under existing accounting pronouncements; accordingly, the standard does not require any new fair value measurements of reported balances. ASC 820 emphasizes that fair value is a market-based measurement, not an entity-specific measurement. Therefore, a fair value measurement should be determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a fair value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the hierarchy). • Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; • Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; • Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. Revenue Recognition Revenue is generated from proprietary and partnered product sales and license and royalty arrangements. Revenue is recognized when or as the Company transfers control of the promised goods or services to its customers in an amount that reflects the consideration to which the Company expects to be entitled to in exchange for those goods or services. When obligations or contingencies remain after the products are shipped, such as training and certifying the treatment centers, revenue is deferred until the obligations or contingencies are satisfied. The Company may enter into contracts with partners that contain multiple elements such as licensing, development, manufacturing, and commercialization components. These arrangements are often complex, and the Company may receive various types of consideration over the life of the arrangement, including up-front fees, reimbursements for research and development services, milestone payments, payments on product shipments, margin sharing arrangements, license fees and royalties. The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers. The core principle of ASC 606 requires that an entity recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASC 606 defines a five-step process to achieve this core principle and, in doing so, it is possible more judgment and estimates may be required within the revenue recognition process, including identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. The following five steps are applied to achieve that core principle: • Step 1: Identify the contract with the customer; • Step 2: Identify the performance obligations in the contract; • Step 3: Determine the transaction price, including an estimation of any variable consideration expected to be received in connection with the contract; • Step 4: Allocate the transaction price to the performance obligations in the contract; and • Step 5: Recognize revenue when the company satisfies a performance obligation. Each of these steps in the revenue recognition process requires management to make judgments and/or estimates. The most significant judgements and estimates involve the determination of variable consideration to be included in the transaction price. Variable consideration is recognized at an amount management believes is not subject to significant reversal and is adjusted at each reporting period if the most likely amount of expected consideration changes or becomes fixed. Management believes this provides a reasonable basis for recognizing revenue; however, actual results could differ from estimates and significant changes in estimates could impact the Company’s results of operations in future periods. The Company’s total revenue and accounts receivable concentration from a CHEMOSAT customer for the year ended and as of December 31, 2023 was 16.1% and 21.1%, respectively, and 20.8% and 41.6%, respectively for the year ended December 31, 2022. As required by ASC 606, the Company disaggregates its revenue into the categories of product revenue and other revenue. The Company recognizes product revenue and milestone payments at a point in time, whereas other revenues (primarily license fees) are recognized over time. Milestone payments that are contingent upon the occurrence of future events, are evaluated and recorded at the most likely amount, and to the extent that it is probable that a significant reversal will not occur when the associated uncertainty is resolved. See Note 15 – Commitments and Contingencies – Litigations, Claims and Assessments – medac Matter. Selling, General and Administrative Selling, general and administrative costs include personnel costs and related expenses for the Company’s sales, marketing, general management and administrative staff, recruitment, costs related to the Company’s commercialization efforts, professional service fees, professional license fees, business development and certain general legal activities. All such costs are charged to expense when incurred. Research and Development Research and development costs include the costs of materials used for clinical trials, personnel costs associated with device and pharmaceutical development expenses, clinical affairs, medical affairs, medical science liaisons, and regulatory affairs, costs of outside services and applicable indirect costs incurred in the development of the Company’s proprietary drug delivery system. All such costs are charged to expense when incurred. Stock Based Compensation The Company accounts for its share-based compensation in accordance with the provisions of ASC 718, Stock-Based Compensation, which establishes accounting for equity instruments exchanged for services. Under the provisions of ASC 718, share-based compensation is measured at the grant date, based upon the fair value of the award, and is recognized as an expense over the option holders’ requisite service period, which is generally the vesting period of the equity grant. The Company expenses its share-based compensation granted under the accelerated method, which treats each vesting tranche as if it were an individual grant. The Company periodically grants stock options for a fixed number of shares of common stock to its employees, directors, and non-employee contractors, with an exercise price greater than or equal to the fair market value of the common stock at the date of the grant. The Company estimates the fair value of stock options using the Black-Scholes option pricing model. Key inputs used to estimate the fair value of stock options include the exercise price of the option, the expected term, the expected volatility of the stock over the option’s expected term, the risk-free interest rate over the option’s expected term, and the expected annual dividend yield. Estimates of fair value are not intended to predict actual future events or the value ultimately realized by persons who receive equity awards. Income Taxes The Company accounts for income taxes following the asset and liability method in accordance with the ASC 740, Income Taxes. Under such method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the consolidated financial statement carrying amounts of existing assets and liabilities and their respective tax bases. The Company applies the accounting guidance issued to address the accounting for uncertain tax positions. This guidance clarifies the accounting for income taxes, by prescribing a minimum recognition threshold a tax position is required to meet before being recognized in the financial statements as well as provides guidance on derecognition, measurement, classification, interest and penalties, accounting in interim periods, disclosure, and transition. The Company classifies interest and penalty expense related to uncertain tax positions as a component of income tax expense. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years that the asset is expected to be recovered or the liability settled. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. The ultimate realization of deferred tax assets depends on the generation of future taxable income during the period in which related temporary differences become deductible. The Company considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in its assessment of a valuation allowance. See Note 17 for additional information. Segment Information A single management team that reports to the Chief Executive Officer comprehensively manages the business. Accordingly, the Company does not have separately reportable segments. Foreign Currency and Currency Translation Transactions that are denominated in a foreign currency are remeasured into the functional currency at the current exchange rate on the date of the transaction. Any foreign currency-denominated monetary assets and liabilities are subsequently remeasured at current exchange rates, with gains or losses recognized as foreign exchange (losses)/gains in the statements of operations. The assets and liabilities of the Company’s international subsidiaries are translated from their functional currencies into United States dollars at exchange rates prevailing at the balance sheet date. The majority of the foreign subsidiaries revenues and operating expenses are denominated in Euros. The reporting currency for the Company is the United States dollar. Average rates of exchange during the period are used to translate the statement of operations, while historical rates of exchange are used to translate any equity transactions. Translation adjustments arising on consolidation due to differences between average rates and balance sheet rates, as well as unrealized foreign exchange gains or losses arising from translation of intercompany loans that are of a long-term-investment nature, are recorded in other comprehensive income. Subsequent Events Management has evaluated events occurring subsequent to the consolidated balance sheet date, through Marc h 26, 2 024, which is the date the consolidated financial statements were issued, determining all subsequent events have been disclosed. Recently Issued Accounting Pronouncements ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. The disclosure requirements must be applied retrospectively to all prior periods presented in the financial statements. The effective date for the standard is for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating the effects adoption of this guidance will have on the consolidated financial statements. ASU 2023-09, Improvements to Income Tax Disclosures On December 14, 2023, the FASB issued, ASU 2023-09, Improvements to Income Tax Disclosures, a final standard on improvements to income tax disclosures. The standard requires disaggregated information about a reporting entity’s effective tax rate reconciliation as well as information on income taxes paid. The standard applies to all entities subject to income taxes and is intended to benefit investors by providing more detailed income tax disclosures that would be useful in making capital allocation decisions. For public business entities (PBEs), the new requirements will be effective for annual periods beginning after December 15, 2024. The guidance will be applied on a prospective basis with the option to apply the standard retrospectively. The Company is currently in the process of evaluating the effect of this guidance on its financial statements.

Cash, Cash Equivalents and Rest

Cash, Cash Equivalents and Restricted Cash	12 Months Ended
	Dec. 31, 2023
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash Cash and cash equivalents that are restricted as to withdrawal or use under the terms of certain contractual agreements are recorded in Restricted Cash on the balance sheet. Restricted cash does not include required minimum balances. December 31, December 31, Cash and cash equivalents $ 12,646 $ 7,671 Restricted balance for loan agreement — 4,000 Letters of credit — 101 Security for credit cards 50 50 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 12,696 $ 11,822 On March 15, 2023, the Company returned to Avenue the $4.0 million held in restricted cash to pay down a portion of the outstanding Avenue Loan balance. See Note 11 - Loans and Convertible Notes Payable - Term Loan from Avenue Venture Opportunities Fund, L.P. for more information. On March 31, 2023, the letter of credit for the sub-lease agreement for office space at 1633 Broadway, New York, NY expired.

Investments

Investments	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Marketable debt securities held by the Company are classified as available-for-sale pursuant to ASC 320, Investments - Debt and Equity Securities, and carried at fair value in the accompanying condensed consolidated balance sheets. The following table summarizes the gross unrealized gains and losses on the Company’s marketable securities: December 31, Gross Unrealized Amortized Cost Gains Losses Credit Losses Estimated Fair Value U.S. government agency bonds $ 19,651 $ 157 $ — $ — $ 19,808 $ 19,651 $ 157 $ — $ — $ 19,808 Classified as: Short-term investments $ 19,808

Inventories

Inventories	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consist of: December 31, December 31, Raw materials $ 1,443 $ 763 Work-in-process 1,753 1,102 Finished goods 126 133 Total inventories $ 3,322 $ 1,998

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	12 Months Ended
	Dec. 31, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets include the following: December 31, December 31, Clinical trial expenses $ 222 $ 1,630 Insurance premiums 157 123 Professional services 133 121 Interest Receivable 151 — Other 428 95 Total prepaid expenses and other current assets $ 1,091 $ 1,969

Property, Plant, and Equipment

Property, Plant, and Equipment	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property, Plant, and Equipment	Property, Plant, and Equipment Property, plant, and equipment consists of: December 31, 2023 December 31, 2022 Estimated Useful Life Buildings and land $ 1,318 $ 1,301 30 years - Buildings Enterprise hardware and software 1,857 1,855 3 years Leaseholds 1,787 1,774 Lesser of lease term or estimated useful life Equipment 1,263 1,222 7 years Furniture 202 201 5 years Property, plant and equipment, gross 6,427 6,353 Accumulated depreciation (5,075) (4,931) Property, plant and equipment, net $ 1,352 $ 1,422 Depreciation expense for the years ended December 31, 2023 and 2022 was $0.1 million and $0.1 million, respectively.

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued Expenses	Accrued Expenses Current accrued expenses include the following: December 31, December 31, Clinical expenses $ 1,129 $ 1,470 Compensation, excluding taxes 1,859 1,040 Professional fees 272 1,087 Interest on convertible note 713 553 Inventory 585 — Other 691 535 Total accrued expenses $ 5,249 $ 4,685

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Leases	Leases The Company recognizes right-of-use (“ROU”) assets and lease liabilities when it obtains the right to control an asset under a leasing arrangement with an initial term greater than twelve months. The Company leases its facilities under non-cancellable operating leases. The Company evaluates the nature of each lease at the inception of an arrangement to determine whether it is an operating or financing lease and recognizes the ROU asset and lease liabilities based on the present value of future minimum lease payments over the expected lease term. The Company’s leases do not generally contain an implicit interest rate and therefore the Company uses the incremental borrowing rate it would expect to pay to borrow on a similar collateralized basis over a similar term in order to determine the present value of its lease payments. On June 25, 2020, the Company entered into a sub-lease agreement (the “2021 Sub-Lease”) with its previous sub-lessee pursuant to which, effective August 2, 2021, the previous sub-lessee would become the lessee and the Company would then sublease its portion of the premises in Galway, Ireland from the previous sub-lessee. The Company’s rent expense under the 2021 Sub-Lease is approximately $3,700 per month for a term of five years. On September 22, 2020, the Company entered into an amendment to a sub-lease agreement executed in March 2016 for approximately 6,877 square feet of office space at 1633 Broadway, New York, NY. The term of the sub-lease agreement began in April 2016 and, pursuant to amendments was extended through August 2023. As of August 31, 2023, this lease has been on a month-to-month basis. No ROU assets or lease liabilities are recognized on the balance sheet for this arrangement. The Company ended the sublease for its former corporate offices at 1633 Broadway, New York, NY in February 2024. For the years ended December 31, 2023 and 2022, lease expense of less than $0.2 million and $0.1 million, respectively, was recorded for short-term leases. The following table summarizes the Company’s operating leases as of December 31, 2023: U.S. Ireland Total Lease cost Operating cash flows from operating leases $ 238 $ 33 $ 271 Weighted average remaining lease term — 2.6 Weighted average discount rate - operating leases 8 % 8 % Maturities of the Company’s operating leases, excluding short-term leases, are as follows: U.S. Ireland Total Year ended December 31, 2024 $ — $ 44 $ 44 Year ended December 31, 2025 — 44 44 Year ended December 31, 2026 — 26 26 Total — 114 114 Less present value discount — (11) (11) Operating lease liabilities included in the condensed consolidated balance sheets at December 31, 2023 $ — $ 103 $ 103

Loans and Convertible Notes Pay

Loans and Convertible Notes Payable	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Loans and Convertible Notes Payable	Loans and Convertible Notes Payable December 31, 2023 December 31, 2022 Gross Discount Net Gross Discount Net Loans payable, current $ 5,610 $ (371) $ 5,239 $ 8,570 $ (724) $ 7,846 Loans payable, non-current — — — 3,353 (283) 3,070 Total - Loans payable 1 $ 5,610 $ (371) $ 5,239 $ 11,923 $ (1,007) $ 10,916 Convertible notes payable - current 5,000 (89) 4,911 — — — Convertible notes payable - non-current — — — 5,000 (228) 4,772 Total - Convertible notes payable $ 5,000 $ (89) $ 4,911 $ 5,000 $ (228) $ 4,772 Total - Loans and notes payable $ 10,610 $ (460) $ 10,150 $ 16,923 $ (1,235) $ 15,688 [1] The gross amount includes the 4.25% final payment of $0.5 million. Remaining maturities of the Company’s loan and convertible note payables are as follows: Loans Convertible Total Year ended December 31, 2024 $ 5,610 $ 5,000 $ 10,610 Year ended December 31, 2025 — — — Total $ 5,610 $ 5,000 $ 10,610 Term Loan from Avenue Venture Opportunities Fund, L.P. On August 6, 2021, the Company entered into a Loan and Security Agreement (the “Avenue Loan Agreement”) with Avenue Venture Opportunities Fund, L.P. (the “Lender,” or “Avenue”) for a term loan in an aggregate principal amount of up to $20.0 million (the “Avenue Loan”). The Avenue Loan bears interest at an annual rate equal to the greater of (a) the sum of 7.70% plus the prime rate as reported in The Wall Street Journal and (b) 10.95%. The interest rate at December 31, 2023 was 16.2%. The Avenue Loan is secured by all of the Company’s assets globally, including intellectual property. The Avenue Loan matures on August 1, 2024. The initial tranche of the Avenue Loan was $15.0 million, including $4.0 million that was funded into a restricted account. On March 15, 2023, the Company returned to Avenue $4.0 million held in the restricted cash to pay down a portion of the outstanding loan balance, principal payments of $2.1 million and an incremental 4.25% of the final payment of $0.2 million. On March 31, 2023, the Avenue Loan Agreement was amended (the “Avenue Amendment”) to defer the interest only period to September 30, 2023, with an additional extension option upon FDA Approval for the HEPZATO KIT and subsequent receipt of at least $10 million from the sale and issuance of equity securities. On August 14, 2023, the Company received FDA approval and has subsequently received over $10 million from the exercise of Tranche A Preferred Warrants. At the Company’s option, it has elected to extend the interest only period to December 31, 2023 and principal payments began in January 2024. Up to $3.0 million of the principal amount of the Avenue Loan outstanding may be converted, at Avenue’s option, into shares of the Company’s common stock at a conversion price of $11.98 per share. The Avenue Loan Agreement requires the Company to make and maintain representations and warranties and other agreements that are customary in loan agreements of this type. The Avenue Loan Agreement also contains customary events of default, including non-payment of principal or interest, violations of covenants, bankruptcy and material judgements. In connection with the initial entry into the Avenue Loan Agreement, the Company issued warrants to Avenue (the “Initial Avenue Warrant”) to purchase 127,755 shares of common stock at an exercise price per share equal to $0.01. The Initial Avenue Warrant is exercisable until August 31, 2026. Additionally, in connection with the Avenue Amendment, the Company issued to Avenue a warrant to purchase 34,072 shares of common stock at an exercise price per share equal to $0.01. The Company determined that the embedded conversion option associated with the Avenue Loan did not require bifurcation and met the criteria for equity classification. In addition, the amendment was recorded under debt modification guidance. Aggregate debt discount amortization of $0.8 million was recorded for the years ended December 31, 2023 and 2022. Interest expense incurred was $1.5 million and $1.9 million for the years ended December 31, 2023 and 2022, respectively. Convertible Notes Payable The Company has $2.0 million of principal outstanding related to Senior Secured Promissory Notes (the “Rosalind Notes”) which bear interest at 8% per annum. Pursuant to their original terms, the Rosalind Notes were convertible into Series E Preferred Stock at a price of $1,500 per share and were to mature on July 16, 2021. On August 6, 2021, the Company executed an agreement to amend the Rosalind Notes to (i) reduce the conversion price to $1,198 per share of the Company’s Series E Convertible Preferred Stock; and (ii) extend the maturity date to October 30, 2024. In addition, the holders of the Rosalind Notes agreed to subordinate all of the Company’s indebtedness and obligations to Avenue and all of the holders ’ security interest, to the Avenue Loan and Avenue ’ s security interest in the Company’s property. Interest expense relating to the Rosalind Notes was $0.2 million for the years ended December 31, 2023 and 2022.

Preferred Purchase Agreement

Preferred Purchase Agreement	12 Months Ended
	Dec. 31, 2023
Preferred Purchase Agreement [Abstract]
Preferred Purchase Agreement	Preferred Purchase Agreement On March 27, 2023, the Company entered into a securities purchase agreement with certain accredited investors (the “Preferred Purchase Agreement”), pursuant to which on March 29, 2023, the Company issued and sold, in a private placement (the “Series F Preferred Offering”), (i) 24,900 shares of Series F-1 Convertible Preferred Stock, par value $0.01 per share (the “Series F-1 Preferred Stock”), (ii) tranche A warrants (the “Preferred Tranche A Warrants”) to acquire 34,859 shares of Series F-3 Convertible Preferred Stock, par value $0.01 per share (the “Series F-3 Preferred Stock”) and (iii) tranche B warrants (the “Preferred Tranche B Warrants”, together with the Preferred Tranche A Warrants, the “Preferred Warrants”) to acquire 24,900 shares of Series F-4 Convertible Preferred Stock, par value $0.01 per share (the “Series F-4 Preferred Stock”) for an aggregate offering price of $24.9 million before deducting the fees paid to the placement agent and the financial advisors and other financing expenses payable by the Company. The gross proceeds of $24.9 million from the Series F Preferred Offering have been allocated first to the Preferred Warrant liabilities at their fair value of $4.9 million, with the residual of $20.0 million being allocated to the Series F-1 Preferred Stock. During the twelve months ended December 31, 2023, all of the Preferred Tranche A Warrants were exercised for an aggregate exercise price of $34.9 million into 34,859 shares of Series F-3 Preferred Stock and since then 23,839 shares of F-3 Preferred Stock were converted into 5,297,550 shares of common stock. The Preferred Tranche B Warrants are exercisable for 24,900 shares of Series F-4 Preferred Stock, with an aggregate exercise price of $24.9 million until the earlier of (i) 21 days following the Company’s announcement of receipt of at least $10 million in quarterly U.S. revenue from the commercialization of HEPZATO and (ii) March 31, 2026. Following stockholder approval, pursuant to the Certificate of Designation of Preferences, Rights and Limitations of the Series F Convertible Voting Preferred Stock (the “Certificate of Designation”), each share of Series F-1 Preferred Stock automatically converted into shares of common stock and/or, if applicable (in accordance with the beneficial ownership limitations then in effect), shares of Series F-2 Preferred Stock, par value $0.01 per share (the “Series F-2 Preferred Stock” and, together with the Series F-1 Preferred Stock, the Series F-3 Preferred Stock and the Series F-4 Preferred Stock, the “Series F Preferred Stock”) in lieu of common stock. Subject to limitations set forth in the Certificate of Designation, the shares of Series F-2, F-3 and F-4 Preferred Stock are convertible into common stock at the option of the holder at the conversion price of $3.30 per share, $4.50 per share and $6.00 per share, respectively, rounded down to the nearest whole share, and in each case subject to the terms and limitations contained in the Certificate of Designation. During the twelve months ended December 31, 2023, 46,197 shares of the Company’s Series F-1, F-2 and F-3 Preferred Stock were converted into 12,073,145 shares of common stock. As of December 31, 2023, there were 2,542 shares of Series F-2 Preferred Stock, 11,020 shares of Series F-3 Preferred Stock and no shares of Series F-4 Preferred Stock outstanding. The Series F-2, F-3 and F-4 Preferred Stock are not mandatorily redeemable, redeemable at the holder’s election or contingently redeemable at the holder’s election (at this point, a Deemed Liquidation Event would potentially trigger pro rata liquidation payments to the preferred and common stockholders on a pro rata “as converted” basis). Accordingly, the Series F-2, F-3 and F-4 Preferred are now classified as permanent equity. The Company determined that the outstanding Preferred Warrants should be liability-classified. See Critical Accounting Estimates - Fair Value Measurements - Warrant Liability

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders’ Equity Public and Private Placements Common Purchase Agreement On March 27, 2023, the Company entered into a securities purchase agreement (the “Common Purchase Agreement”) with the Company’s Chief Executive Officer, Gerard Michel, pursuant to which the Company agreed to issue and sell, in a private placement (the “Common Offering”) shares of common stock, tranche A warrants (“Common Tranche A Warrants”) to acquire 31,110 shares of common stock, tranche B warrants (“Common Tranche B Warrants”, together with the Common Tranche A Warrants, the “Common Warrants”) to acquire 16,666 shares of common stock. On March 29, 2023, the Company closed the Common Offering. The aggregate exercise price of the Common Tranche A Warrants issued pursuant to the Common Offering is approximately $0.1 million. On August 14, 2023, the Company announced the receipt of the FDA Approval and all Common Tranche A Warrants were exercised and converted into 31,110 shares of common stock. The aggregate exercise price of the Common Tranche B Warrants issued in the Common Offering is approximately $0.1 million. The Common Tranche B Warrants are exercisable for an aggregate of 16,666 shares of common stock until the earlier of 21 days following the Company’s announcement of receipt of recording at least $10 million in quarterly U.S. revenue from the commercialization of HEPZATO and March 31, 2026. Registration Rights for Preferred and Common Offerings Pursuant to the Preferred Purchase Agreement and the Common Purchase Agreement (collectively, the “Purchase Agreements”), the Company filed a registration statement on Form S-3 (the “Resale Registration Statement”) providing for the resale by the investors party thereto of the common stock issuable upon conversion of the Registrable Shares (as defined in the Purchase Agreements). The Resale Registration Statement became effective on June 28, 2023. There is no established public trading market for the Series F Preferred Stock, the Preferred Warrants, or the Common Warrants and the Company does not intend to list such securities on any national securities exchange or nationally recognized trading system. At-the-Market Offering The Company has entered into a Controlled Equity Offering SM Sales Agreement (“ATM Sales Agreement” ), with Cantor Fitzgerald & Co. (the “Sales Agent”), pursuant to which the Company may offer and sell, at its sole discretion through the Sales Agent, shares of common stock having an aggregate offering price of up to $17.0 million. To date, the Company has sold approximately $4.0 million of its common stock, prior to issuance costs, under the ATM Sales Agreement. No sales were made during the year ended December 31, 2023. Authorized Shares In June 2023, stockholders approved an amendment to the Company’s Amended and Restated Certificate of Incorporation to increase the total number of shares of its common stock authorized for issuance from 40 million to 80 million shares. The company is authorized to issue 80 million shares of common stock, $0.01 par value, and 10 million shares of preferred stock, $0.01 par value. As of December 31, 2023, the Company has designated the following preferred stock: Designated Preferred Shares December 31, 2023 Series A 4,200 Series B 2,360 Series C 590 Series D 10,000 Series E 40,000 Series E-1 12,960 Series F-1 24,900 Series F-2 24,900 Series F-3 34,860 Series F-4 24,900 Total 179,670 Preferred Stock As of December 31, 2023, there were an aggregate of 11,257 shares of Series E and Series E-1, 2,542 Series F-2 and 11,020 Series F-3 Convertible Preferred Stock outstanding, respectively. Equity Incentive Plans On September 30, 2020, the Company’s 2020 Omnibus Equity Incentive Plan (the “2020 Plan”) was adopted by the Company’s Board of Directors. On November 23, 2020, the Company’s stockholders approved the 2020 Plan. The 2020 Plan will continue in effect until the tenth anniversary of the date of its adoption by the Board or until earlier terminated by the Board. The 2020 Plan is administered by the Board of Directors or a committee designated by the Board of Directors. On June 12, 2023, the stockholders approved the amendment to the Company’s 2020 Plan to increase the number of shares of common stock available under the plan by 2.65 million shares. The 2020 Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance awards, as well as other stock-based awards or cash awards that are deemed to be consistent with the purposes of the plan to Company employees, directors and consultants. As of December 31, 2023, there are 5,123,742 shares of common stock reserved under the 2020 Plan for future issuance, of which 1,837,509 remained available to be granted. In addition to options granted from the 2020 Plan, the Company also grants employment inducement awards pursuant to Listing Rule 5635(c)(4) of the corporate governance rules of the NASDAQ Stock Market. The inducement grants are intended to provide incentive to certain individuals to enter into employment with the Company. Prior to December 5, 2023, the inducement awards were granted outside of the 2020 Plan, however they are governed in all respects as if they were issued under the 2020 Plan. These grants do not reduce the number of options available for issuance under the 2020 Plan. On December 5, 2023, the Company’s 2023 Inducement Plan (the “2023 Plan”) was adopted by the Company’s Board of Directors. The 2023 Plan is administered by a Compensation Committee of two or more Independent Directors appointed by the Board of Directors and is intended to provide for the grant of non-qualified stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance awards, as well as other stock-based awards or cash awards that are deemed appropriate to incentivize employment with the Company. Awards from the 2023 Plan can only be granted to individuals who have not previously worked for the Company or have not worked for the Company for a bona fide period of time. As of December 31, 2023, there are 650,000 shares of common stock reserved under the 2023 Plan, of which 623,000 remain available to be granted. Stock Options The following table sets forth information as of December 31, 2023 with respect to compensation plans (including individual compensation arrangements) under which shares of common stock of the Company are authorized for issuance. Plan category Number of securities to be issued upon exercise of outstanding options, warrants and rights (a) Weighted-average exercise price of outstanding options, warrants and rights (b) Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column (a)) (c) Equity compensation plans approved by security holders 3,286,233 $ 7.69 1,837,509 Equity compensation plans not approved by security holders (1) 896,999 $ 9.93 623,000 Total 4,183,232 $ 8.17 2,460,509 (1) Includes (a) stock options for an aggregate of 499 shares of common stock issued under the Company’s 2019 Equity Incentive Plan, which allows for grants in the form of incentive stock options, non-qualified stock options, stock units, stock awards, stock appreciation rights, and other stock-based awards to the Company’s officers, directors, employees, consultants, and advisors, including options to purchase shares of common stock at exercise prices not less than 100% of fair value on the dates of grant. As of November 2, 2020, no additional grants may be made under this plan, which has been superseded by the Company’s 2020 Omnibus Equity Incentive Plan; however, outstanding awards granted under this plan will remain outstanding and continue to be administered in accordance with the terms of this plan and the applicable award agreements; (b) pursuant to an employment agreement dated as of August 31, 2020 between the Company and Gerard Michel, the Company’s Chief Executive Officer, on October 1, 2020, a non-qualified and non-plan stock option “inducement award” to purchase 498,000 shares of the Company’s common stock in reliance on Nasdaq Rule 5635(c)(4) pursuant to the terms of a stock option award agreement between the Company and Mr. Michel; and (c) new hire inducement awards to purchase 398,500 shares of the Company’s common stock in reliance on Nasdaq Rule 5635(c)(4) pursuant to the terms of a stock option award agreement between the Company and 12 employees hired during 2022 and 2023. The following tables include information for all options granted, including inducement grants that are granted outside of the 2020 Plan. The Company values stock options using the Black-Scholes option pricing model and used the following assumptions during the reporting periods: Years Ended December 31 2023 2022 Expected terms (years) 0.8 - 5.9 0.7 - 8.4 Expected volatility 96.4% -172.8% 166.4.% - 180.3% Risk-free interest rate 3.9% - 5.4% 1.2% - 4.4% Expected dividends 0.00% 0.00% The weighted average estimated fair value of the stock options granted during the years ended December 31, 2023 and 2022 was approximately $5.62 and $6.05 per share, respectively. The following is a summary of stock option activity for the year ended December 31, 2023: Number of Options Weighted Average Exercise Price Per Share Weighted Average Grant Date Fair Value Per Share Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Outstanding at January 1, 2023 2,235,052 $ 10.30 $ 9.40 7.7 $ 36 Granted 2,218,757 5.97 5.62 9.1 Exercised (819) 4.67 4.51 $ 1 Expired (141,059) 8.40 5.76 Cancelled/Forfeited (128,699) 7.02 6.74 Outstanding at December 31, 2023 4,183,232 $ 8.17 $ 7.60 8.3 $ 147 Exercisable at December 31, 2023 2,252,556 $ 9.93 $ 9.15 7.6 $ 24 Unvested at December 31, 2023 1,930,676 $ 6.12 $ 5.79 9.1 $ 123 The following table summarizes information for stock option shares outstanding and exercisable at December 31, 2023: Options Exercisable Range of Exercise Prices Outstanding Number of Weighted Average Number of Options 2.83 - $51.50 4,182,733 8.3 2,252,057 51.50+ 499 5.1 499 4,183,232 8.3 2,252,556 The following is a summary of the share-based compensation expense in the statement of operations for the twelve months ended December 31, 2023: Years Ended 2023 2022 Selling, general and administrative $ 4,944 $ 5,282 Research and development 2,837 2,449 Cost of goods sold 370 210 Total $ 8,151 $ 7,941 At December 31, 2023, there was approximately $5.9 million of aggregate unrecognized compensation expense related to employee, consultant and Non-employee Director stock option grants. The Company does not estimate forfeitures and only recognizes forfeitures as they occur. The cost is expected to be recognized over a weighted average period of 2.1 years. Employee Stock Purchase Plan In August 2021, the Company’s Board of Directors, with shareholder approval in May 2022, adopted the Employee Stock Purchase Plan (the “ESPP”). The ESPP provides for a maximum of 260,295 shares of common stock to be purchased by participating employees of which 41,435 have been issued as of December 31, 2023 since the inception of the benefit in 2021. Employees who elect to participate in the ESPP will be able to purchase common stock at the lower of 85% of the fair market value of common stock on the first or last day of the applicable six-month offering period. In January 2024, an aggregate 21,140 shares were purchased by participating employees for the offering period of July 3, 2023 to December 29, 2023. Common Stock Warrants The following is a summary of common stock warrant activity for the year ended December 31, 2023: Warrants Weighted Average Weighted Average Outstanding at January 1, 2023 5,153,291 $ 7.01 Warrants issued 81,848 2.94 Warrants exercised (569,938) $ 0.26 Outstanding at December 31, 2023 4,665,201 $ 7.76 1.6 Exercisable at December 31, 2023 4,665,201 $ 7.76 1.6 The following table presents information related to stock warrants at December 31, 2023: Warrants Exercisable Range of Exercise Prices Outstanding Number Weighted Average Number of $0.01 1,037,792 3.2 1,037,792 $6.00 16,666 2.2 16,666 $10.00 3,610,743 1.2 3,610,743 4,665,201 1.6 4,665,201 Preferred Stock Warrants The following is a summary of preferred stock warrant activity for the year ended December 31, 2023: Warrants Weighted Average Weighted Average Outstanding at January 1, 2023 — $ — Warrants issued 59,759 1,000.00 Warrants exercised (34,859) $ 1,000.00 Outstanding at December 31, 2023 24,900 $ 1,000.00 2.3 Exercisable at December 31, 2023 24,900 $ 1,000.00 2.3

Net Loss per Share

Net Loss per Share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Net Loss per Share	Net Loss Per Share Basic net loss per share is determined by dividing net loss by the weighted average shares of common stock outstanding during the period, without consideration of potentially dilutive securities, except for those shares that are issuable for little or no cash consideration. Diluted net loss per share is determined by dividing net loss by diluted weighted average shares outstanding. Diluted weighted average shares reflects the dilutive effect, if any, of potentially dilutive common shares, such as stock options, stock purchased pursuant to the Company’s employee stock purchase plan, convertible notes and warrants calculated using the treasury stock method. In periods with reported net operating losses, all common stock options and warrants are generally deemed anti-dilutive such that basic net loss per share and diluted net loss per share are equal. For the years ended December 31, 2023 and 2022 the following potentially dilutive securities were excluded from the computation of diluted earnings per share because their effects would be antidilutive: December 31, 2023 2022 Common stock warrants - equity 3,627,409 3,610,743 Assumed conversion of preferred stock warrants 4,149,994 — Assumed conversion of preferred stock 4,344,909 1,135,721 Assumed conversion of convertible notes 488,031 488,031 Stock options 4,183,232 2,235,052 Total 16,793,575 7,469,547 At December 31, 2023, the Company had 1,037,792 pre-funded warrants outstanding. The following tables provides a reconciliation of the weighted average shares outstanding calculation for the year-ended December 31, 2023 and 2022. Year ended December 31, 2023 2022 Weighted average shares issued 15,039,630 8,290,529 Weighted average pre-funded warrants 1,190,301 574,086 Weighted average shares outstanding 16,229,931 8,864,615

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Litigation, Claims and Assessments medac Matter In April 2021, the Company’s wholly-owned subsidiary, Delcath Systems Ltd, issued to medac GmbH, a privately held, multi-national pharmaceutical company based in Germany (“medac”), an invoice for a €1 million milestone payment under a License, Supply and Marketing Agreement dated December 10, 2018 (the “medac Agreement”) between medac and the Company. The medac Agreement provided to medac the exclusive right to market and sell CHEMOSAT in certain designated countries for which the Company was entitled to a combination of upfront and success-based milestone payments as well as a fixed transfer price per unit of CHEMOSAT and specified royalties. In response to medac’s subsequent dispute and non-payment of the invoice, on October 12, 2021, the Company notified medac in writing that it was terminating the medac Agreement due to medac’s nonpayment of the €1 million milestone payment, with the effective date of termination of the medac Agreement being April 12, 2022. On December 16, 2021, the Company initiated an arbitration proceeding pursuant to the dispute resolution procedures of the medac Agreement for the non-payment of the invoice. On December 30, 2022, the parties reached a final settlement of the matter and the Company agreed to pay medac either (a) royalty on sales of CHEMOSAT units over a defined minimum for a period of five years or until a maximum payment has been reached, or (b) a minimum annual payment of $0.2 million in the event the annual royalty payment does not reach the agreed minimum payment amount. As of December 31, 2023, the Company has estimated the settlement to be $1.0 million and recorded $0.8 million as other liabilities, non-current and $0.2 million as accrued expenses on the Company’s condensed consolidated balance sheet. Lachman Consulting Services, Inc On January 24, 2023, Lachman Consultant Services, Inc. (“Lachman”) served the Company with a complaint alleging that Delcath owed Lachman approximately $0.9 million in unpaid consulting fees plus interest, costs and attorneys’ fees. The dispute arises from a July 22, 2021 agreement between Lachman and Delcath under which Lachman provided assistance to the Company in regard to preparing for a FDA inspection and good manufacturing practices, training and support. A settlement was reached on July 5, 2023, under which the Company paid Lachman $0.9 million. Manufacturing and Supply Agreements three

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Leases On January 18, 2024 (the “Lease Commencement Date”), the Company entered into a lease agreement (the “Queensbury Lease”) to lease approximately 18,000 square feet of manufacturing and office space in Queensbury, New York (the “Premises”). The initial term of the lease is 5 years with a right to extend the lease by an additional 5 years, exercisable under certain conditions set forth in the Queensbury Lease. The initial term is expected to begin within 90 days of the Lease Commencement Date. The annual base rent of the Queensbury Lease is initially $8 per square foot per year, subject to annual 3% increases in years four and five. Additionally, the Company is responsible for reimbursing the landlord for the Company’s share of the Premises ’ property taxes. Securities Purchase Agreement On March 14, 2024, the Company and certain accredited investors (each an “Investor” and collectively, the “Investors”) entered into a securities purchase agreement (the “Securities Purchase Agreement”) pursuant to which the Company agreed to sell and issue to the Investors in a private placement (the “Private Placement”) (i) an aggregate of 876,627 shares (the “Shares”) of the Company’s common stock, par value $0.01 per share (the “Common Stock”), at a purchase price of $3.72 per share, and (ii) to certain investors, in lieu of shares of Common Stock, 1,008,102 pre-funded warrants (the “Pre-Funded Warrants”) at a price per Pre-Funded Warrant of $3.71 (the “Warrant Shares” and together with the Shares, the “Securities”). The Pre-Funded Warrants will have an exercise price of $0.01 per share of Common Stock, be immediately exercisable and remain exercisable until exercised in full.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes There is no income tax provision for the years ended December 31, 2023 and 2022, respectively. Loss before income taxes consists of: For the Year Ended 2023 2022 Domestic $ (41,303) $ (34,547) Foreign (6,375) (1,960) Income before taxes $ (47,678) $ (36,507) The provision for income taxes differs from the amount computed by applying the statutory rate as follows: For the Year Ended 2023 2022 Income taxes using U.S federal statutory rate $ (10,012) $ (7,666) Nondeductible interest 127 139 Branch income (1,230) (385) State income taxes, net of federal benefit (31) (531) Foreign rate differential 506 165 Valuation allowance 7,099 9,221 Stock option expense, exercises and cancellations 2,899 752 Research and development costs (859) (708) Other (179) (987) Derivative Charge 1,680 — $ — $ — Significant components of the Company’s deferred tax assets are as follows: For the Year Ended 2023 2022 Deferred tax assets: Employee compensation accruals $ 1,377 $ 2,772 Accrued liabilities 54 197 Research tax credits 2,330 1,429 Lease obligation 4 38 Other 233 160 Research expense capitalization 5,441 3,203 Net operating losses 29,875 24,595 Total deferred tax assets $ 39,314 $ 32,394 For the Year Ended 2023 2022 Deferred tax liabilities: Right of use asset $ 13 $ 50 Total deferred tax liabilities 13 50 Valuation allowance 39,301 32,344 Net deferred tax assets $ — $ — As of December 31, 2023, and 2022, the Company had net operating loss carryforwards for U.S. federal income tax purposes of approximately $307.6 million and $290.4 million, respectively. A significant portion of the federal amount is subject to an annual limitation as low as $28 as a result of changes in the Company’s ownership in May 2003, November 2016, and multiple dates throughout 2017, 2018, 2019, 2021 and 2023, as defined by Section 382 of the United States Internal Revenue Code of 1986, as amended (the “IRC”), and the related income tax regulations. As a result of the limitations caused by the multiple ownership changes, approximately $200.5 million of the total net operating loss carryforwards is expected to expire unutilized and will be unavailable to offset future federal taxable income. Approximately $107.1 million of net operating loss carryforwards remains available to offset future federal taxable income, of which $1.7 million will expire between 2024 and 2037 and $105.4 million will have an unlimited carryforward period. In addition, the Company’s state net operating losses are also subject to annual limitations that generally follow the IRC Section 382 provisions (with the exception of Connecticut and Florida), adjusted for each state’s respective income apportionment percentages. As of December 31, 2023, and 2022, the Company had net operating loss carryforwards for states and city income tax purposes between approximately $0.8 million and $196.0 million and between approximately $0.3 million and $195.3 million, respectively, which expire through 2043. As a result of the Section 382 limitations, approximately $191.1 million and $175.4 million of New York State and New York City net operating losses are expected to expire unutilized and will be unavailable to offset future taxable income. Approximately $5.0 million and $4.9 million of net operating loss carryforwards, respectively, will be available to offset future state and city taxable income. As of December 31, 2023 and 2022, the Company had a net operating loss carryforward for foreign income tax purposes of $43.3 million and $33.4 million, respectively, which have indefinite carryforward periods. As of December 31, 2023 and 2022, the Company had federal research and development tax credit carryforwards of approximately $7.4 million and $6.5 million, respectively, which expire through 2043. As a result of the Section 382 limitations, all but $2.3 million of the tax credit carryforwards is expected to expire unutilized. Management has established a 100% valuation allowance against the deferred tax assets as management does not believe it is more likely than not that these assets will be realized. The Company’s valuation allowance increased by approximately $7.0 million and $9.2 million in 2023 and 2022, respectively. The change in valuation allowance is as follows: December 31, 2023 2022 Beginning Balance $ 32,344 $ 23,125 Charged to costs and expenses 7,099 9,221 Charged to other comprehensive income (142) (2) Ending balance $ 39,301 $ 32,344 The Company complies with the provisions of ASC 740-10 in accounting for its uncertain tax positions. ASC 740-10 addresses the determination of whether tax benefits claimed or expected to be claimed on a tax return should be recorded in the financial statements. Under ASC 740-10, the Company may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The Company has determined that the Company has no significant uncertain tax positions requiring recognition under ASC 740-10 and therefore has not included a tabular roll forward of unrecognized tax benefits. As there are no uncertain tax positions recognized, interest and penalties have not been accrued. The Company is subject to income tax in the United States, as well as various state and international jurisdictions. The Company has not been audited by any state tax authorities in connection with income taxes. The Company has not been audited by international tax authorities or any states in connection with income taxes. The Company’s New York State tax returns have been subject to annual desk reviews which have resulted in insignificant adjustments to the related franchise tax liabilities and credits. The Company is no longer subject to federal and state examination for tax years ending prior to December 31, 2020; tax years ending December 31, 2020 through December 31, 2023 remain open to examination. The Republic of Ireland is the Company’s only significant foreign jurisdiction. The Company is no longer subject to Ireland tax examination for tax years ending prior to December 31, 2018 (as Ireland has not initiated an audit of 2017 as of December 31, 2023); tax years ending December 31, 2019 through December 31, 2023 remain open to examination. However, the Company’s tax years December 31, 1998 through December 31, 2023 generally remain open to adjustment for all federal, state and foreign tax matters until its net operating loss and tax credit carryforwards are utilized or expire prior to utilization, and the applicable statutes of limitation have expired in the utilization year. The federal and state tax authorities can generally reduce a net operating loss (but not create taxable income) for a period outside the statute of limitations in order to determine the correct amount of net operating loss which may be allowed as a deduction against income for a period within the statute of limitations. The Company recognizes interest accrued related to unrecognized tax benefits and penalties, if incurred, as a component of income tax expense. The Company ’ s foreign subsidiaries have generally incurred losses since inception and the Company has no material undistributed earnings as of December 31, 2023.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company’s fair value measurements are classified and disclosed in one of the following three categories: • Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; • Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; • Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). The table below presents activity within Level 3 of the fair value hierarchy and the Company’s liabilities carried at fair value for the year ended December 31, 2023: Level 3 Contingent Liabilities Warrant Liabilities Total Balance at January 1, 2023 $ 1,280 $ — $ 1,280 Fair value of warrant liabilities issued — 4,940 4,940 Total change in exchange rate 46 — 46 Fair value adjustment (330) 1,688 1,358 Change due to warrant exercise — (1,080) (1,080) Balance at December 31, 2023 $ 996 $ 5,548 $ 6,544 Contingent liabilities are re-measured to fair value each reporting period using projected financial targets, discount rates, probabilities of payment, and projected payment dates. Projected contingent payment amounts are discounted back to the current period using a discounted cash flow model. Projected financial targets are based on the Company’s most recent internal operational budgets and may take into consideration alternate scenarios that could result in more or less profitability for the respective service line. Increases or decreases in projected financial targets and probabilities of payment may result in significant changes in the fair value measurements. Increases in discount rates and the time to payment may result in lower fair value measurements. Increases or decreases in any of those inputs in isolation may result in a significantly lower or higher fair value measurement. As disclosed in Note 12 of the Company’s consolidated financial statements, the Company allocated part of the proceeds of the Series F Preferred Offering to warrant liability issued in connection with the transaction. The valuations of the warrants were determined using option pricing models. The Company concluded that the Preferred Warrants were not in the scope of ASC 480, Distinguishing Liabilities from Equity, since the Preferred Warrants are not mandatorily redeemable; and do not have obligations to issue a variable number of shares of preferred stock. The Company determined the Preferred Warrants met the definition of a derivative in accordance with ASC 815 but were not considered indexed to the Company’s common stock since the warrants require early settlement by repurchasing the preferred warrants for cash in an amount equal to the Black-Scholes value in the event of a Fundamental Transaction at pre-specified volatility of 100% as an input to the Black-Scholes calculation. The Company determined to record the Preferred Warrants at fair value with subsequent changes in fair value recorded in earnings at the end of each reporting period. For the twelve months ended December 31, 2023, the Company recorded other expense of $8.0 million related to the change in fair value of the warrant liability and Tranche A Warrant exercises. These models use inputs such as the underlying price of the shares issued at the measurement date, volatility, risk free interest rate and expected life of the instrument. The Company has classified the warrants as a long-term liability due to certain provisions relating to the holders’ ability to exercise the warrants beyond twelve months of the reporting date. The fair value of the preferred and common warrants at December 31, 2023 and March 29, 2023 was determined by using option pricing models assuming the following: March 29, 2023 December 31, 2023 Risk free interest rate 3.80% - 4.80% 4.09% Expected term (years) 0.5 - 3.0 2.3 Expected volatility 70% - 75% 70% Expected dividends 0.00% 0.00% Additionally, the Company has determined that the warrant liability should be classified within Level 3 of the fair-value hierarchy by evaluating each input for the option pricing models against the fair-value hierarchy criteria and using the lowest level of input as the basis for the fair-value classification as called for in ASC 820. There are six inputs: closing price of the Company’s stock on the day of evaluation; the exercise price of the warrants; the remaining term of the warrants; the volatility of the Company’s stock over that term; annual rate of dividends; and the risk-free rate of return. Of those inputs, the exercise price of the warrants and the remaining term are readily observable in the warrant agreements. The annual rate of dividends is based on the Company’s historical practice of not granting dividends. The closing price of the Company’s stock would fall under Level 1 of the fair-value hierarchy as it is a quoted price in an active market, the risk-free rate of return is a Level 2 input, while the historical volatility is a Level 3 input as defined in ASC 820-10. Since the lowest level input is a Level 3, the Company determined the warrant liability is most appropriately classified within Level 3 of the fair value hierarchy. The following tables present information about the Company’s financial assets and liabilities that have been measured at fair value as of December 31, 2023 and December 31, 2022 and indicate the fair value hierarchy of the valuation inputs utilized to determine such fair value. December 31, December 31, Description Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets: Money market funds $ 392 $ — $ — $ 392 $ — $ — $ — $ — U.S. government agency bonds — 19,808 — 19,808 — — — — Total Assets 392 $ 19,808 $ — $ 20,200 $ — $ — $ — $ — Liabilities: Contingent Liability $ — $ — $ 996 $ 996 $ — $ — $ 1,280 $ 1,280 Warrant Liabilities — — 5,548 5,548 — — — — Total Liabilities $ — $ — $ 6,544 $ 6,544 $ — $ — $ 1,280 $ 1,280

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net loss	$ (47,678)	$ (36,508)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The Company bases its estimates and judgments on historical experience and on various other assumptions that it believes are reasonable under the circumstances. The amounts of assets and liabilities reported in the Company’s consolidated balance sheets and the amount of revenues and expenses reported for each of the periods presented are affected by estimates and assumptions, which are used for, but not limited to, the accounting for valuation of warrants, stock-based compensation, valuation of inventory, impairment of long-lived assets, income taxes and operating expense accruals. Such assumptions and estimates are subject to change in the future as additional information becomes available or as circumstances are modified. Actual results could differ from these estimates.
Cash Equivalents and Concentrations of Credit Risk	Cash Equivalents and Concentrations of Credit Risk
Restricted Cash	Restricted Cash
Investments	Investments
Accounts Receivable	Accounts Receivable
Inventories	Inventories
Property, Plant and Equipment	Property, Plant and Equipment Property, plant, and equipment are recorded at cost, less accumulated depreciation. The Company provides for depreciation on a straight-line basis over the estimated useful lives of the assets which range from three
Leases	Leases The Company determines if an arrangement is a lease at inception, in accordance with Accounting Standards Codification (“ASC”) Topic 842, Leases. All operating lease commitments with a lease term greater than 12 months are recognized as right-of-use assets and lease liabilities, on a discounted basis on the balance sheet. Leases with an initial term of 12 months or less are not recorded on the balance sheet. Certain of the Company’s lease agreements include lease payments that are adjusted periodically for an index or rate. The leases are initially measured using the present value of the projected payments adjusted for the index or rate in effect at the commencement date. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance and other expenses, which do not transfer a good or service to the Company and are generally referred to as non-lease components. Variable non-lease components are not measured as part of the right-of-use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and are recognized as part of a right-of-use asset and liability. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. The Company may have options to renew lease terms for facilities and other assets. Some leases contain clauses for renewal at the Company’s option with renewal terms that generally extend the lease term from 1 to 5 years. The exercise of lease renewal options is generally at the Company’s sole discretion. The Company evaluates renewal and termination options at the lease commencement date to determine if it is reasonably certain to exercise the option on the basis of economic factors.
Fair Value Measurements	Fair Value Measurements The Company adheres to ASC 820, Fair Value Measurement, which defines fair value, establishes a framework for measuring fair value, and expands disclosures about fair value measurements. ASC 820 applies to reported balances that are required or permitted to be measured at fair value under existing accounting pronouncements; accordingly, the standard does not require any new fair value measurements of reported balances. ASC 820 emphasizes that fair value is a market-based measurement, not an entity-specific measurement. Therefore, a fair value measurement should be determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a fair value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the hierarchy). • Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; • Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; • Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).
Revenue Recognition	Revenue Recognition Revenue is generated from proprietary and partnered product sales and license and royalty arrangements. Revenue is recognized when or as the Company transfers control of the promised goods or services to its customers in an amount that reflects the consideration to which the Company expects to be entitled to in exchange for those goods or services. When obligations or contingencies remain after the products are shipped, such as training and certifying the treatment centers, revenue is deferred until the obligations or contingencies are satisfied. The Company may enter into contracts with partners that contain multiple elements such as licensing, development, manufacturing, and commercialization components. These arrangements are often complex, and the Company may receive various types of consideration over the life of the arrangement, including up-front fees, reimbursements for research and development services, milestone payments, payments on product shipments, margin sharing arrangements, license fees and royalties. The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers. The core principle of ASC 606 requires that an entity recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASC 606 defines a five-step process to achieve this core principle and, in doing so, it is possible more judgment and estimates may be required within the revenue recognition process, including identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. The following five steps are applied to achieve that core principle: • Step 1: Identify the contract with the customer; • Step 2: Identify the performance obligations in the contract; • Step 3: Determine the transaction price, including an estimation of any variable consideration expected to be received in connection with the contract; • Step 4: Allocate the transaction price to the performance obligations in the contract; and • Step 5: Recognize revenue when the company satisfies a performance obligation. Each of these steps in the revenue recognition process requires management to make judgments and/or estimates. The most significant judgements and estimates involve the determination of variable consideration to be included in the transaction price. Variable consideration is recognized at an amount management believes is not subject to significant reversal and is adjusted at each reporting period if the most likely amount of expected consideration changes or becomes fixed. Management believes this provides a reasonable basis for recognizing revenue; however, actual results could differ from estimates and significant changes in estimates could impact the Company’s results of operations in future periods. The Company’s total revenue and accounts receivable concentration from a CHEMOSAT customer for the year ended and as of December 31, 2023 was 16.1% and 21.1%, respectively, and 20.8% and 41.6%, respectively for the year ended December 31, 2022.
Selling, General and Administrative	Selling, General and Administrative
Research and Development	Research and Development
Stock Based Compensation	Stock Based Compensation The Company accounts for its share-based compensation in accordance with the provisions of ASC 718, Stock-Based Compensation, which establishes accounting for equity instruments exchanged for services. Under the provisions of ASC 718, share-based compensation is measured at the grant date, based upon the fair value of the award, and is recognized as an expense over the option holders’ requisite service period, which is generally the vesting period of the equity grant. The Company expenses its share-based compensation granted under the accelerated method, which treats each vesting tranche as if it were an individual grant.
Income Taxes	Income Taxes
Segment Information	Segment Information
Foreign Currency and Currency Translation	Foreign Currency and Currency Translation Transactions that are denominated in a foreign currency are remeasured into the functional currency at the current exchange rate on the date of the transaction. Any foreign currency-denominated monetary assets and liabilities are subsequently remeasured at current exchange rates, with gains or losses recognized as foreign exchange (losses)/gains in the statements of operations. The assets and liabilities of the Company’s international subsidiaries are translated from their functional currencies into United States dollars at exchange rates prevailing at the balance sheet date. The majority of the foreign subsidiaries revenues and operating expenses are denominated in Euros. The reporting currency for the Company is the United States dollar. Average rates of exchange during the period are used to translate the statement of operations, while historical rates of exchange are used to translate any equity transactions. Translation adjustments arising on consolidation due to differences between average rates and balance sheet rates, as well as unrealized foreign exchange gains or losses arising from translation of intercompany loans that are of a long-term-investment nature, are recorded in other comprehensive income.
Subsequent Events	Subsequent Events Management has evaluated events occurring subsequent to the consolidated balance sheet date, through Marc h 26, 2
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. The disclosure requirements must be applied retrospectively to all prior periods presented in the financial statements. The effective date for the standard is for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating the effects adoption of this guidance will have on the consolidated financial statements. ASU 2023-09, Improvements to Income Tax Disclosures On December 14, 2023, the FASB issued, ASU 2023-09, Improvements to Income Tax Disclosures, a final standard on improvements to income tax disclosures. The standard requires disaggregated information about a reporting entity’s effective tax rate reconciliation as well as information on income taxes paid. The standard applies to all entities subject to income taxes and is intended to benefit investors by providing more detailed income tax disclosures that would be useful in making capital allocation decisions. For public business entities (PBEs), the new requirements will be effective for annual periods beginning after December 15, 2024. The guidance will be applied on a prospective basis with the option to apply the standard retrospectively. The Company is currently in the process of evaluating the effect of this guidance on its financial statements.

Cash, Cash Equivalents and Re_2

Cash, Cash Equivalents and Restricted Cash (Tables)	12 Months Ended
	Dec. 31, 2023
Cash and Cash Equivalents [Abstract]
Schedule of cash, cash equivalents and restricted cash	December 31, December 31, Cash and cash equivalents $ 12,646 $ 7,671 Restricted balance for loan agreement — 4,000 Letters of credit — 101 Security for credit cards 50 50 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 12,696 $ 11,822

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Schedule of unrealized gains and losses	The following table summarizes the gross unrealized gains and losses on the Company’s marketable securities: December 31, Gross Unrealized Amortized Cost Gains Losses Credit Losses Estimated Fair Value U.S. government agency bonds $ 19,651 $ 157 $ — $ — $ 19,808 $ 19,651 $ 157 $ — $ — $ 19,808 Classified as: Short-term investments $ 19,808

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Schedule of inventories	Inventories consist of: December 31, December 31, Raw materials $ 1,443 $ 763 Work-in-process 1,753 1,102 Finished goods 126 133 Total inventories $ 3,322 $ 1,998

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid expenses and other current assets	Prepaid expenses and other current assets include the following: December 31, December 31, Clinical trial expenses $ 222 $ 1,630 Insurance premiums 157 123 Professional services 133 121 Interest Receivable 151 — Other 428 95 Total prepaid expenses and other current assets $ 1,091 $ 1,969

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Components of property, plant and equipment	Property, plant, and equipment consists of: December 31, 2023 December 31, 2022 Estimated Useful Life Buildings and land $ 1,318 $ 1,301 30 years - Buildings Enterprise hardware and software 1,857 1,855 3 years Leaseholds 1,787 1,774 Lesser of lease term or estimated useful life Equipment 1,263 1,222 7 years Furniture 202 201 5 years Property, plant and equipment, gross 6,427 6,353 Accumulated depreciation (5,075) (4,931) Property, plant and equipment, net $ 1,352 $ 1,422

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Schedule of accrued expenses	Current accrued expenses include the following: December 31, December 31, Clinical expenses $ 1,129 $ 1,470 Compensation, excluding taxes 1,859 1,040 Professional fees 272 1,087 Interest on convertible note 713 553 Inventory 585 — Other 691 535 Total accrued expenses $ 5,249 $ 4,685

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Summary of operating leases	The following table summarizes the Company’s operating leases as of December 31, 2023: U.S. Ireland Total Lease cost Operating cash flows from operating leases $ 238 $ 33 $ 271 Weighted average remaining lease term — 2.6 Weighted average discount rate - operating leases 8 % 8 %
Maturities of operating leases	Maturities of the Company’s operating leases, excluding short-term leases, are as follows: U.S. Ireland Total Year ended December 31, 2024 $ — $ 44 $ 44 Year ended December 31, 2025 — 44 44 Year ended December 31, 2026 — 26 26 Total — 114 114 Less present value discount — (11) (11) Operating lease liabilities included in the condensed consolidated balance sheets at December 31, 2023 $ — $ 103 $ 103

Loans and Convertible Notes P_2

Loans and Convertible Notes Payable (Tables)	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Summary of loans and convertible notes payable	December 31, 2023 December 31, 2022 Gross Discount Net Gross Discount Net Loans payable, current $ 5,610 $ (371) $ 5,239 $ 8,570 $ (724) $ 7,846 Loans payable, non-current — — — 3,353 (283) 3,070 Total - Loans payable 1 $ 5,610 $ (371) $ 5,239 $ 11,923 $ (1,007) $ 10,916 Convertible notes payable - current 5,000 (89) 4,911 — — — Convertible notes payable - non-current — — — 5,000 (228) 4,772 Total - Convertible notes payable $ 5,000 $ (89) $ 4,911 $ 5,000 $ (228) $ 4,772 Total - Loans and notes payable $ 10,610 $ (460) $ 10,150 $ 16,923 $ (1,235) $ 15,688 [1] The gross amount includes the 4.25% final payment of $0.5 million.
Summary of remaining maturities of loan and convertible notes payable	Remaining maturities of the Company’s loan and convertible note payables are as follows: Loans Convertible Total Year ended December 31, 2024 $ 5,610 $ 5,000 $ 10,610 Year ended December 31, 2025 — — — Total $ 5,610 $ 5,000 $ 10,610

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Schedule of stock by class	As of December 31, 2023, the Company has designated the following preferred stock: Designated Preferred Shares December 31, 2023 Series A 4,200 Series B 2,360 Series C 590 Series D 10,000 Series E 40,000 Series E-1 12,960 Series F-1 24,900 Series F-2 24,900 Series F-3 34,860 Series F-4 24,900 Total 179,670
Schedule of compensation plans	The following table sets forth information as of December 31, 2023 with respect to compensation plans (including individual compensation arrangements) under which shares of common stock of the Company are authorized for issuance. Plan category Number of securities to be issued upon exercise of outstanding options, warrants and rights (a) Weighted-average exercise price of outstanding options, warrants and rights (b) Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column (a)) (c) Equity compensation plans approved by security holders 3,286,233 $ 7.69 1,837,509 Equity compensation plans not approved by security holders (1) 896,999 $ 9.93 623,000 Total 4,183,232 $ 8.17 2,460,509 (1)
Summary of valuation assumptions	The Company values stock options using the Black-Scholes option pricing model and used the following assumptions during the reporting periods: Years Ended December 31 2023 2022 Expected terms (years) 0.8 - 5.9 0.7 - 8.4 Expected volatility 96.4% -172.8% 166.4.% - 180.3% Risk-free interest rate 3.9% - 5.4% 1.2% - 4.4% Expected dividends 0.00% 0.00%
Summary of stock option activity	The following is a summary of stock option activity for the year ended December 31, 2023: Number of Options Weighted Average Exercise Price Per Share Weighted Average Grant Date Fair Value Per Share Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Outstanding at January 1, 2023 2,235,052 $ 10.30 $ 9.40 7.7 $ 36 Granted 2,218,757 5.97 5.62 9.1 Exercised (819) 4.67 4.51 $ 1 Expired (141,059) 8.40 5.76 Cancelled/Forfeited (128,699) 7.02 6.74 Outstanding at December 31, 2023 4,183,232 $ 8.17 $ 7.60 8.3 $ 147 Exercisable at December 31, 2023 2,252,556 $ 9.93 $ 9.15 7.6 $ 24 Unvested at December 31, 2023 1,930,676 $ 6.12 $ 5.79 9.1 $ 123
Summary of stock option shares outstanding and exercisable	The following table summarizes information for stock option shares outstanding and exercisable at December 31, 2023: Options Exercisable Range of Exercise Prices Outstanding Number of Weighted Average Number of Options 2.83 - $51.50 4,182,733 8.3 2,252,057 51.50+ 499 5.1 499 4,183,232 8.3 2,252,556
Summary of recognized share-based compensation cost	The following is a summary of the share-based compensation expense in the statement of operations for the twelve months ended December 31, 2023: Years Ended 2023 2022 Selling, general and administrative $ 4,944 $ 5,282 Research and development 2,837 2,449 Cost of goods sold 370 210 Total $ 8,151 $ 7,941
Summary of warrant activity	The following is a summary of common stock warrant activity for the year ended December 31, 2023: Warrants Weighted Average Weighted Average Outstanding at January 1, 2023 5,153,291 $ 7.01 Warrants issued 81,848 2.94 Warrants exercised (569,938) $ 0.26 Outstanding at December 31, 2023 4,665,201 $ 7.76 1.6 Exercisable at December 31, 2023 4,665,201 $ 7.76 1.6 The following is a summary of preferred stock warrant activity for the year ended December 31, 2023: Warrants Weighted Average Weighted Average Outstanding at January 1, 2023 — $ — Warrants issued 59,759 1,000.00 Warrants exercised (34,859) $ 1,000.00 Outstanding at December 31, 2023 24,900 $ 1,000.00 2.3 Exercisable at December 31, 2023 24,900 $ 1,000.00 2.3
Schedule of information related to stock warrants	The following table presents information related to stock warrants at December 31, 2023: Warrants Exercisable Range of Exercise Prices Outstanding Number Weighted Average Number of $0.01 1,037,792 3.2 1,037,792 $6.00 16,666 2.2 16,666 $10.00 3,610,743 1.2 3,610,743 4,665,201 1.6 4,665,201

Net Loss per Share (Tables)

Net Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Anti-dilutive securities excluded from the computation of earnings per share	For the years ended December 31, 2023 and 2022 the following potentially dilutive securities were excluded from the computation of diluted earnings per share because their effects would be antidilutive: December 31, 2023 2022 Common stock warrants - equity 3,627,409 3,610,743 Assumed conversion of preferred stock warrants 4,149,994 — Assumed conversion of preferred stock 4,344,909 1,135,721 Assumed conversion of convertible notes 488,031 488,031 Stock options 4,183,232 2,235,052 Total 16,793,575 7,469,547
Summary of reconciliation of weighted average shares outstanding calculation	The following tables provides a reconciliation of the weighted average shares outstanding calculation for the year-ended December 31, 2023 and 2022. Year ended December 31, 2023 2022 Weighted average shares issued 15,039,630 8,290,529 Weighted average pre-funded warrants 1,190,301 574,086 Weighted average shares outstanding 16,229,931 8,864,615

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of loss before income taxes	Loss before income taxes consists of: For the Year Ended 2023 2022 Domestic $ (41,303) $ (34,547) Foreign (6,375) (1,960) Income before taxes $ (47,678) $ (36,507)
Income tax reconciliation	The provision for income taxes differs from the amount computed by applying the statutory rate as follows: For the Year Ended 2023 2022 Income taxes using U.S federal statutory rate $ (10,012) $ (7,666) Nondeductible interest 127 139 Branch income (1,230) (385) State income taxes, net of federal benefit (31) (531) Foreign rate differential 506 165 Valuation allowance 7,099 9,221 Stock option expense, exercises and cancellations 2,899 752 Research and development costs (859) (708) Other (179) (987) Derivative Charge 1,680 — $ — $ —
Significant components of deferred tax assets and liabilities	Significant components of the Company’s deferred tax assets are as follows: For the Year Ended 2023 2022 Deferred tax assets: Employee compensation accruals $ 1,377 $ 2,772 Accrued liabilities 54 197 Research tax credits 2,330 1,429 Lease obligation 4 38 Other 233 160 Research expense capitalization 5,441 3,203 Net operating losses 29,875 24,595 Total deferred tax assets $ 39,314 $ 32,394 For the Year Ended 2023 2022 Deferred tax liabilities: Right of use asset $ 13 $ 50 Total deferred tax liabilities 13 50 Valuation allowance 39,301 32,344 Net deferred tax assets $ — $ —
Summary of change in valuation allowance	The change in valuation allowance is as follows: December 31, 2023 2022 Beginning Balance $ 32,344 $ 23,125 Charged to costs and expenses 7,099 9,221 Charged to other comprehensive income (142) (2) Ending balance $ 39,301 $ 32,344

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair value measurements using significant unobservable inputs	The table below presents activity within Level 3 of the fair value hierarchy and the Company’s liabilities carried at fair value for the year ended December 31, 2023: Level 3 Contingent Liabilities Warrant Liabilities Total Balance at January 1, 2023 $ 1,280 $ — $ 1,280 Fair value of warrant liabilities issued — 4,940 4,940 Total change in exchange rate 46 — 46 Fair value adjustment (330) 1,688 1,358 Change due to warrant exercise — (1,080) (1,080) Balance at December 31, 2023 $ 996 $ 5,548 $ 6,544
Fair value assumptions	The fair value of the preferred and common warrants at December 31, 2023 and March 29, 2023 was determined by using option pricing models assuming the following: March 29, 2023 December 31, 2023 Risk free interest rate 3.80% - 4.80% 4.09% Expected term (years) 0.5 - 3.0 2.3 Expected volatility 70% - 75% 70% Expected dividends 0.00% 0.00%
Assets and liabilities measured at fair value	The following tables present information about the Company’s financial assets and liabilities that have been measured at fair value as of December 31, 2023 and December 31, 2022 and indicate the fair value hierarchy of the valuation inputs utilized to determine such fair value. December 31, December 31, Description Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets: Money market funds $ 392 $ — $ — $ 392 $ — $ — $ — $ — U.S. government agency bonds — 19,808 — 19,808 — — — — Total Assets 392 $ 19,808 $ — $ 20,200 $ — $ — $ — $ — Liabilities: Contingent Liability $ — $ — $ 996 $ 996 $ — $ — $ 1,280 $ 1,280 Warrant Liabilities — — 5,548 5,548 — — — — Total Liabilities $ — $ — $ 6,544 $ 6,544 $ — $ — $ 1,280 $ 1,280

Description of Business (Detail

Description of Business (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Cash, cash equivalents and restricted cash	$ 12,696	$ 11,822	$ 26,953
Short-term investments	19,808	0
Cash used in operating activities	31,251	24,950
Principal payments	6,313	$ 714
Accounts Payable Accrued Expenses And Lease Liabilities
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Current capital commitments	6,300
Loan Principal Payments
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Current capital commitments	10,600
Lease Liabilities
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Noncurrent capital commitments	5,000
Third Party Settlement
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Noncurrent capital commitments	100
Convertibe Note Principal Payments
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Noncurrent capital commitments	$ 800

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Summary Of Significant Accounting Policies [Line Items]
Maximum period of investments with original maturities from date of acquisition to be cash equivalents	3 months
Customer Concentration Risk | Revenue Benchmark | Chemosat
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	16.10%	20.80%
Customer Concentration Risk | Accounts Receivable | Chemosat
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	21.10%	41.60%
Minimum
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	3 years
Extension term	1 year
Maximum
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	7 years
Extension term	5 years

Cash, Cash Equivalents and Re_3

Cash, Cash Equivalents and Restricted Cash - Schedule of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 12,646	$ 7,671
Restricted balance for loan agreement	0	4,000
Letters of credit	0	101
Security for credit cards	50	50
Total	$ 12,696	$ 11,822	$ 26,953

Cash, Cash Equivalents and Re_4

Cash, Cash Equivalents and Restricted Cash - Schedule of Cash, Cash Equivalents, and Restricted Cash - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Mar. 15, 2023	Dec. 31, 2022
Cash and Cash Equivalents [Line Items]
Restricted Cash	$ 50		$ 4,151
Avenue Loan
Cash and Cash Equivalents [Line Items]
Restricted Cash		$ 4,000

Investments (Details)

Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 19,651
Gross Unrealized Gains	157
Gross Unrealized Losses	0
Gross Unrealized Credit Loss	0
Estimated Fair Value	19,808	$ 0
Interest Receivable	151	$ 0
U.S. government agency bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	19,651
Gross Unrealized Gains	157
Gross Unrealized Losses	0
Gross Unrealized Credit Loss	0
Estimated Fair Value	$ 19,808

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Inventory Disclosure [Abstract]
Raw materials	$ 1,443	$ 763
Work-in-process	1,753	1,102
Finished goods	126	133
Total inventories	$ 3,322	$ 1,998

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Prepaid Expense and Other Assets, Current [Abstract]
Clinical trial expenses	$ 222	$ 1,630
Insurance premiums	157	123
Professional services	133	121
Interest receivable	151	0
Other	428	95
Total prepaid expenses and other current assets	$ 1,091	$ 1,969

Property, Plant, and Equipmen_2

Property, Plant, and Equipment - Components of Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 6,427	$ 6,353
Accumulated depreciation	(5,075)	(4,931)
Property, plant and equipment, net	1,352	1,422
Buildings and land
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1,318	1,301
Buildings
Property Plant And Equipment [Line Items]
Estimated Useful Life	30 years
Enterprise hardware and software
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1,857	1,855
Estimated Useful Life	3 years
Leaseholds
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1,787	1,774
Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1,263	1,222
Estimated Useful Life	7 years
Furniture
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 202	$ 201
Estimated Useful Life	5 years

Property, Plant, and Equipmen_3

Property, Plant, and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 128	$ 132

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Clinical expenses	$ 1,129	$ 1,470
Compensation, excluding taxes	1,859	1,040
Professional fees	272	1,087
Interest on convertible note	713	553
Inventory	585	0
Other	691	535
Total accrued expenses	$ 5,249	$ 4,685

Leases - Additional Information

Leases - Additional Information (Details) $ in Millions		12 Months Ended
	Jun. 25, 2020 $ / ft²	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 22, 2020 ft²
Lessee Lease Description [Line Items]
Short-term lease, cost | $		$ 0.2	$ 0.1
2021 Sub-Lease
Lessee Lease Description [Line Items]
Monthly base rent (in USD per sq ft) | $ / ft²	3,700
Lease term	5 years
2016 Sub-Lease
Lessee Lease Description [Line Items]
Area of space | ft²				6,877

Leases - Summary of Operating L

Leases - Summary of Operating Leases (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Lease cost
Operating cash flows from operating leases	$ 271
U.S.
Lease cost
Operating cash flows from operating leases	$ 238
Weighted average discount rate - operating leases	8%
Ireland
Lease cost
Operating cash flows from operating leases	$ 33
Weighted average remaining lease term	2 years 7 months 6 days
Weighted average discount rate - operating leases	8%

Leases - Schedule of Remaining

Leases - Schedule of Remaining Maturities of Operating Leases (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Lessee Lease Description [Line Items]
Year ended December 31, 2024	$ 44
Year ended December 31, 2025	44
Year ended December 31, 2026	26
Total	114
Less present value discount	(11)
Operating lease liabilities included in the condensed consolidated balance sheets at December 31, 2023	103
U.S.
Lessee Lease Description [Line Items]
Year ended December 31, 2024	0
Year ended December 31, 2025	0
Year ended December 31, 2026	0
Total	0
Less present value discount	0
Operating lease liabilities included in the condensed consolidated balance sheets at December 31, 2023	0
Ireland
Lessee Lease Description [Line Items]
Year ended December 31, 2024	44
Year ended December 31, 2025	44
Year ended December 31, 2026	26
Total	114
Less present value discount	(11)
Operating lease liabilities included in the condensed consolidated balance sheets at December 31, 2023	$ 103

Loans and Convertible Notes P_3

Loans and Convertible Notes Payable - Summary of Loans and Convertible Notes Payable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Loans and notes payable, gross	$ 10,610	$ 16,923
Discount	(460)	(1,235)
Loans and notes payable, net	$ 10,150	15,688
Percentage of final payment included in gross amount	4.25%
Final payment	$ 500
Loans Payable
Debt Instrument [Line Items]
Loans and notes payable, current, gross	5,610	8,570
Loans and notes payable, non-current, gross	0	3,353
Loans and notes payable, gross	5,610	11,923
Discount, current	(371)	(724)
Discount, non-current	0	(283)
Discount	(371)	(1,007)
Loans and notes payable, current, net	5,239	7,846
Loans and notes payable, non-current, net	0	3,070
Loans and notes payable, net	5,239	10,916
Convertible Notes Payable
Debt Instrument [Line Items]
Loans and notes payable, current, gross	5,000	0
Loans and notes payable, non-current, gross	0	5,000
Loans and notes payable, gross	5,000	5,000
Discount, current	(89)	0
Discount, non-current	0	(228)
Discount	(89)	(228)
Loans and notes payable, current, net	4,911	0
Loans and notes payable, non-current, net	0	4,772
Loans and notes payable, net	$ 4,911	$ 4,772

Loans and Convertible Notes P_4

Loans and Convertible Notes Payable - Summary of Remaining Maturities of Company's Loan and Convertible Note Payables (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Loans	$ 5,610
Convertible Notes	5,000
Total	10,610
Year ended December 31, 2024
Debt Instrument [Line Items]
Loans	5,610
Convertible Notes	5,000
Total	10,610
Year ended December 31, 2025
Debt Instrument [Line Items]
Loans	0
Convertible Notes	0
Total	$ 0

Loans and Convertible Notes P_5

Loans and Convertible Notes Payable - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands					12 Months Ended
	Aug. 14, 2023	Mar. 31, 2023	Mar. 15, 2023	Aug. 06, 2021	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Restricted Cash					$ 50	$ 4,151
Final payment					500
Proceeds from exercise of warrants					$ 35,004	0
Preferred Tranche A Warrant
Debt Instrument [Line Items]
Proceeds from exercise of warrants	$ 10,000
Avenue Loan
Debt Instrument [Line Items]
Debt instrument, principal face amount				$ 3,000
Debt instrument, interest rate (as a percent)				7.70%
Debt instrument, interest rate				10.95%	16.20%
Initial tranche of loan			$ 15,000
Loan amount funded into restricted account			4,000
Restricted Cash			4,000
Principal payment			$ 2,100
Debt instrument, incremental final payment			4.25%
Final payment			$ 200
Debt instrument, conversion price (in dollars per share)				$ 11.98
Amortization of premiums and discounts on marketable securities					$ 800	800
Interest expense incurred					1,500	1,900
Avenue Loan | Warrant
Debt Instrument [Line Items]
Warrants issued to purchase of common stock (in shares)				127,755
Warrant exercise price (in dollars per share)				$ 0.01
Avenue Loan | Condition for the Extension of Period of Interest Only Payments
Debt Instrument [Line Items]
Estimated minimum proceeds on issue of common stock for extension of due date of interest only interest payments		$ 10,000
Warrant exercise price (in dollars per share)		$ 0.01
Number of warrants outstanding (in shares)		34,072
Rosalind Notes | Convertible Debt
Debt Instrument [Line Items]
Interest expense incurred					$ 200	$ 200
Rosalind Notes | Series E
Debt Instrument [Line Items]
Debt instrument, conversion price (in dollars per share)					$ 1,500
Rosalind Notes | Secured Convertible Notes Payable
Debt Instrument [Line Items]
Debt instrument, principal face amount				$ 2,000
Rosalind Notes | Secured Convertible Notes Payable | Series E
Debt Instrument [Line Items]
Debt instrument, conversion price (in dollars per share)				$ 1,198
Rosalind Notes | Convertible Notes Payable
Debt Instrument [Line Items]
Debt instrument, interest rate (as a percent)					8%
Maximum | Avenue Loan
Debt Instrument [Line Items]
Debt instrument, principal face amount				$ 20,000

Preferred Purchase Agreement (D

Preferred Purchase Agreement (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Mar. 29, 2023	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Disclosure Of Preferred Purchase Agreement [Line Items]
Preferred stock, par value (in dollars per share)		$ 0.01	$ 0.01	$ 0.01
Fair value of warrant liabilities		$ 6,544		$ 1,280
Deferred revenue	$ 10,000	$ 10,000
Preferred stock, shares outstanding (in shares)		24,819		11,357
Series F-3
Disclosure Of Preferred Purchase Agreement [Line Items]
Preferred stock, par value (in dollars per share)		$ 4.50
Preferred stock, shares outstanding (in shares)		11,020
Common Stock
Disclosure Of Preferred Purchase Agreement [Line Items]
Number of shares converted (in shares)		12,073,145
Series F-4
Disclosure Of Preferred Purchase Agreement [Line Items]
Preferred stock, par value (in dollars per share)		$ 6
Preferred stock, shares outstanding (in shares)		0
Series F-2
Disclosure Of Preferred Purchase Agreement [Line Items]
Preferred stock, par value (in dollars per share)		$ 3.30
Preferred stock, shares outstanding (in shares)		2,542
Series F1, Series F2 and F3 Preferred Stock
Disclosure Of Preferred Purchase Agreement [Line Items]
Conversion of Preferred Shares to common stock (in shares)		46,197
Preferred Tranche A Warrant | Series F-3
Disclosure Of Preferred Purchase Agreement [Line Items]
Number of exercisable preferred warrants (in shares)	34,859
Preferred Warrant Liabilities
Disclosure Of Preferred Purchase Agreement [Line Items]
Proceeds from issuance of warrants	$ 24,900
Fair value of warrant liabilities	4,900
Preferred Warrant Liabilities | Series F-1
Disclosure Of Preferred Purchase Agreement [Line Items]
Proceeds from issuance of warrants	$ 20,000
Preferred Purchase Agreement | Series F-1
Disclosure Of Preferred Purchase Agreement [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred Purchase Agreement | Series F-3
Disclosure Of Preferred Purchase Agreement [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred Purchase Agreement | Common Stock
Disclosure Of Preferred Purchase Agreement [Line Items]
Number of shares converted (in shares)		5,297,550
Preferred Purchase Agreement | Series F-2
Disclosure Of Preferred Purchase Agreement [Line Items]
Preferred stock, par value (in dollars per share)		$ 0.01
Preferred Purchase Agreement | Series F-1
Disclosure Of Preferred Purchase Agreement [Line Items]
Number of exercisable preferred warrants (in shares)	24,900
Preferred Purchase Agreement | Preferred Tranche A Warrant
Disclosure Of Preferred Purchase Agreement [Line Items]
Number of exercisable preferred warrants (in shares)		34,859
Aggregate exercise price of preferred warrants		$ 34,900
Preferred Purchase Agreement | Preferred Tranche A Warrant | Common Stock
Disclosure Of Preferred Purchase Agreement [Line Items]
Conversion of Preferred Shares to common stock (in shares)		23,839
Preferred Purchase Agreement | Preferred Tranche B Warrant
Disclosure Of Preferred Purchase Agreement [Line Items]
Aggregate exercise price of preferred warrants		$ 24,900
Warrant exercise period		21 days
Preferred Purchase Agreement | Series F-4
Disclosure Of Preferred Purchase Agreement [Line Items]
Number of exercisable preferred warrants (in shares)		24,900

Stockholders' Equity - Equity O

Stockholders' Equity - Equity Offerings and Placements (Details) - USD ($) $ in Millions	Mar. 29, 2023	Dec. 31, 2023	Aug. 14, 2023	Mar. 27, 2023
Stockholders Equity Note [Line Items]
Deferred revenue	$ 10	$ 10
Tranche A Warrants | Common Purchase Agreement
Stockholders Equity Note [Line Items]
Number of warrants outstanding (in shares)			31,110	31,110
Aggregate exercise price of preferred warrants	0.1
Tranche B Warrants | Common Purchase Agreement
Stockholders Equity Note [Line Items]
Number of warrants outstanding (in shares)				16,666
Aggregate exercise price of preferred warrants	$ 0.1
Warrants exercisable, period		21 days

Stockholders' Equity - At-the-M

Stockholders' Equity - At-the-Market Offering (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stockholders Equity Note [Line Items]
Sale of stock consideration received on the transaction	$ 228	$ 100
Number of shares sold (in shares)	0
Controlled Equity Offering Sales Agreement | Cantor Fitzgerald & Co
Stockholders Equity Note [Line Items]
Common stock, aggregate offering price	$ 17,000
Sale of stock consideration received on the transaction	$ 4,000

Stockholders' Equity - Authoriz

Stockholders' Equity - Authorized Shares and Preferred Stock (Details) - $ / shares	Dec. 31, 2023	Jun. 30, 2023	May 31, 2023	Dec. 31, 2022
Stockholders Equity Note [Line Items]
Common stock, shares authorized (in shares)	80,000,000	80,000,000	40,000,000	80,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01		$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000		10,000,000
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01		$ 0.01
Preferred stock, shares outstanding (in shares)	24,819			11,357
Series E
Stockholders Equity Note [Line Items]
Preferred stock, shares outstanding (in shares)	11,257
Series E-1
Stockholders Equity Note [Line Items]
Preferred stock, shares outstanding (in shares)	11,257
Series F-2
Stockholders Equity Note [Line Items]
Preferred stock, par value (in dollars per share)	$ 3.30
Preferred stock, shares outstanding (in shares)	2,542
Series F-3
Stockholders Equity Note [Line Items]
Preferred stock, par value (in dollars per share)	$ 4.50
Preferred stock, shares outstanding (in shares)	11,020

Stockholders' Equity - Designat

Stockholders' Equity - Designated Preferred Shares (Details)	Dec. 31, 2023 shares
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	179,670
Series A
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	4,200
Series B
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	2,360
Series C
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	590
Series D
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	10,000
Series E
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	40,000
Series E-1
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	12,960
Series F-1
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	24,900
Series F-2
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	24,900
Series F-3
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	34,860
Series F-4
Class of Stock [Line Items]
Preferred stock, shares designated (in shares)	24,900

Stockholders' Equity - Equity I

Stockholders' Equity - Equity Incentive Plan (Details) - shares	Jun. 12, 2023	Dec. 31, 2023
2020 Plan
Class Of Warrant Or Right [Line Items]
Increase in shares available under equity incentive plan (in shares)	2,650,000
Common stock capital shares reserved (in shares)		5,123,742
Number of shares available for grant (in shares)		1,837,509
2023 Plan
Class Of Warrant Or Right [Line Items]
Common stock capital shares reserved (in shares)		650,000
Number of shares available for grant (in shares)		623,000

Stockholders' Equity - Common S

Stockholders' Equity - Common Stock of the Company are Authorized For Issuance (Details)		12 Months Ended	24 Months Ended
	Oct. 01, 2020 shares	Dec. 31, 2023 $ / shares shares	Dec. 31, 2023 employee $ / shares shares
Class Of Warrant Or Right [Line Items]
Number of securities to be issued upon exercise of outstanding options, warrants and rights (in shares)		4,183,232	4,183,232
Weighted-average exercise price of outstanding options, warrants and rights (in dollars per share) | $ / shares		$ 8.17	$ 8.17
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column) (in shares)		2,460,509	2,460,509
Exercise price as a percentage of fair value		100%
Granted (in shares)		2,218,757
Number of employees hired | employee			12
CEO Inducement Award Options
Class Of Warrant Or Right [Line Items]
Granted (in shares)	498,000
New Hire Inducement Award Options
Class Of Warrant Or Right [Line Items]
Granted (in shares)		398,500
Equity compensation plans approved by security holders
Class Of Warrant Or Right [Line Items]
Number of securities to be issued upon exercise of outstanding options, warrants and rights (in shares)		3,286,233	3,286,233
Weighted-average exercise price of outstanding options, warrants and rights (in dollars per share) | $ / shares		$ 7.69	$ 7.69
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column) (in shares)		1,837,509	1,837,509
Equity compensation plans not approved by security holders
Class Of Warrant Or Right [Line Items]
Number of securities to be issued upon exercise of outstanding options, warrants and rights (in shares)		896,999	896,999
Weighted-average exercise price of outstanding options, warrants and rights (in dollars per share) | $ / shares		$ 9.93	$ 9.93
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column) (in shares)		623,000	623,000
2019 Equity Incentive Plan
Class Of Warrant Or Right [Line Items]
Common Stock issued (in shares)		499	499

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Assumptions to Estimate Fair Value of Stock Options Using Black-Scholes Option Pricing Model (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividends	0%	0%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected terms (years)	9 months 18 days	8 months 12 days
Expected volatility	96.40%	166.40%
Risk-free interest rate	3.90%	1.20%
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected terms (years)	5 years 10 months 24 days	8 years 4 months 24 days
Expected volatility	172.80%	180.30%
Risk-free interest rate	5.40%	4.40%

Stockholders' Equity - Stock Op

Stockholders' Equity - Stock Options Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Weighted average estimated fair value of the stock options granted (in dollars per share)	$ 5.62	$ 6.05
Unrecognized compensation expense related to non-vested share-based compensation awards	$ 5.9
Cost expected to be recognized over weighted average period (in years)	2 years 1 month 6 days

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Options
Outstanding, beginning of period (in shares)	2,235,052
Granted (in shares)	2,218,757
Exercised (in shares)	(819)
Expired (in shares)	(141,059)
Cancelled/Forfeited (in shares)	(128,699)
Outstanding, end of period (in shares)	4,183,232	2,235,052
Exercisable (in shares)	2,252,556
Unvested at December 31, 2023 (in shares)	1,930,676
Weighted Average Exercise Price Per Share
Outstanding, Weighted Average Exercise Price Per Share, beginning of period (in dollars per share)	$ 10.30
Granted, Weighted Average Exercise Price Per Share (in dollars per share)	5.97
Exercised, Weighted Average Exercise Price Per Share (in dollars per share)	4.67
Expired, Weighted Average Exercise Price Per Share (in dollars per share)	8.40
Cancelled-Forfeited, Weighted Average Exercise Price Per Share (in dollars per share)	7.02
Outstanding, Weighted Average Exercise Price Per Share, end of period (in dollars per share)	8.17	$ 10.30
Weighted Average Exercise Price, Exercisable (in dollars per share)	9.93
Weighted Average Exercise Price, Unvested (in dollars per share)	6.12
Weighted Average Grant Date Fair Value Per Share
Outstanding, Weighted average grant date fair value at beginning of period (in dollars per share)	9.40
Weighted average estimated fair value of the stock options granted (in dollars per share)	5.62	6.05
Exercised, Weighted average grant date fair value (in dollars per share)	4.51
Expired, Weighted average grant date fair value (in dollars per share)	5.76
Cancelled/Forfeited, Weighted average grant date fair value (in dollars per share)	6.74
Ending, Weighted average grant date fair value at beginning of period (in dollars per share)	7.60	$ 9.40
Exercisable, Weighted average grant date fair value (in dollars per share)	9.15
Unvested Weighted average grant date fair value (in dollars per share)	$ 5.79
Weighted Average Remaining Contractual Term (in years) and Aggregate Intrinsic Value
Weighted Average Remaining Contractual Term (in years)	8 years 3 months 18 days	7 years 8 months 12 days
Weighted Average Remaining Contractual Term (in years), Granted	9 years 1 month 6 days
Weighted Average Remaining Contractual Term (Years), Exercisable	7 years 7 months 6 days
Weighted Average Remaining Contractual Term (in years), Unvested	9 years 1 month 6 days
Aggregate Intrinsic Value, Outstanding	$ 147	$ 36
Aggregate Intrinsic Value, Exercised	1
Aggregate Intrinsic Value, Exercisable	24
Aggregate Intrinsic Value, Unvested	$ 123

Stockholders' Equity - Summar_2

Stockholders' Equity - Summary of Stock Option Shares Outstanding and Exercisable (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of securities to be issued upon exercise of outstanding options, warrants and rights (in shares)	4,183,232	2,235,052
Weighted Average Remaining Option Term (in years)	8 years 3 months 18 days	7 years 8 months 12 days
Number of Options Exercisable (in shares)	2,252,556
$2.83 - $51.50
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of securities to be issued upon exercise of outstanding options, warrants and rights (in shares)	4,182,733
Weighted Average Remaining Option Term (in years)	8 years 3 months 18 days
Number of Options Exercisable (in shares)	2,252,057
$2.83 - $51.50 | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Range of Exercise Prices (in dollars per share)	$ 2.83
$2.83 - $51.50 | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Range of Exercise Prices (in dollars per share)	$ 51.50
51.50+
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of securities to be issued upon exercise of outstanding options, warrants and rights (in shares)	499
Weighted Average Remaining Option Term (in years)	5 years 1 month 6 days
Number of Options Exercisable (in shares)	499
Range of Exercise Prices (in dollars per share)	$ 51.50

Stockholders' Equity - Summar_3

Stockholders' Equity - Summary of Recognized Share-based Compensation Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	$ 8,151	$ 7,941
Selling, general and administrative
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	4,944	5,282
Research and development
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	2,837	2,449
Cost of goods sold
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	$ 370	$ 210

Stockholders' Equity - Summar_4

Stockholders' Equity - Summary of Employee Stock Purchase Plan (Details) - May 2022 Employee Stock Purchase Plan - shares	1 Months Ended		29 Months Ended
	Jan. 31, 2024	Aug. 31, 2021	Dec. 31, 2023
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Share-based compensation arrangement by share-based payment award number of shares authorized (in shares)		260,295
Share-based compensation arrangement by share-based payment award purchase price of common stock (as a percent)		85%
Employee stock purchase plan, offering period		6 months
Employee Stock
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares issued in period (in shares)			41,435
Employee Stock | Subsequent Event
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares issued in period (in shares)	21,140

Stockholders' Equity - Common_2

Stockholders' Equity - Common Stock Warrants (Details) - Common Warrants - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Class Of Warrant Or Right [Line Items]
Outstanding Number of Warrants (in shares)	4,665,201	5,153,291
Class Of Warrant Or Right Weighted Average Exercise Price (in dollars per share)	$ 7.76	$ 7.01
Warrants issued (in shares)	81,848
Warrants issued (in dollars per share)	$ 2.94
Warrants exercised (in shares)	(569,938)
Warrants exercised (in dollars per share)	$ 0.26
Warrants Exercisable, Weighted Average Remaining Warrant Term (in years)	1 year 7 months 6 days
Warrants Exercisable, Number of Warrants (in shares)	4,665,201
Warrants Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 7.76
Weighted Average Remaining Life, Exercisable	1 year 7 months 6 days

Stockholders' Equity - Summar_5

Stockholders' Equity - Summary of Warrants Outstanding and Exercisable (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Common Warrants
Class Of Warrant Or Right [Line Items]
Outstanding Number of Warrants (in shares)	4,665,201	5,153,291
Warrants Exercisable, Weighted Average Remaining Warrant Term (in years)	1 year 7 months 6 days
Warrants Exercisable, Number of Warrants (in shares)	4,665,201
$0.01
Class Of Warrant Or Right [Line Items]
Warrant exercise price (in dollars per share)	$ 0.01
$0.01 | Common Warrants
Class Of Warrant Or Right [Line Items]
Outstanding Number of Warrants (in shares)	1,037,792
Warrants Exercisable, Weighted Average Remaining Warrant Term (in years)	3 years 2 months 12 days
Warrants Exercisable, Number of Warrants (in shares)	1,037,792
$6.00
Class Of Warrant Or Right [Line Items]
Warrant exercise price (in dollars per share)	$ 6
$6.00 | Common Warrants
Class Of Warrant Or Right [Line Items]
Outstanding Number of Warrants (in shares)	16,666
Warrants Exercisable, Weighted Average Remaining Warrant Term (in years)	2 years 2 months 12 days
Warrants Exercisable, Number of Warrants (in shares)	16,666
$10.00
Class Of Warrant Or Right [Line Items]
Warrant exercise price (in dollars per share)	$ 10
$10.00 | Common Warrants
Class Of Warrant Or Right [Line Items]
Outstanding Number of Warrants (in shares)	3,610,743
Warrants Exercisable, Weighted Average Remaining Warrant Term (in years)	1 year 2 months 12 days
Warrants Exercisable, Number of Warrants (in shares)	3,610,743

Stockholders' Equity - Preferre

Stockholders' Equity - Preferred Stock Warrants (Details) - Preferred Warrants - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Class Of Warrant Or Right [Line Items]
Outstanding Number of Warrants (in shares)	24,900	0
Class Of Warrant Or Right Weighted Average Exercise Price (in dollars per share)	$ 1,000	$ 0
Warrants issued (in shares)	59,759
Warrants issued (in dollars per share)	$ 1,000
Warrants exercised (in shares)	(34,859)
Warrants exercised (in dollars per share)	$ 1,000
Warrants Exercisable, Weighted Average Remaining Warrant Term (in years)	2 years 3 months 18 days
Warrants Exercisable, Number of Warrants (in shares)	24,900
Warrants Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 1,000
Weighted Average Remaining Life, Exercisable	2 years 3 months 18 days

Net Loss per Share - Anti-Dilut

Net Loss per Share - Anti-Dilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	16,793,575	7,469,547
Common stock warrants - equity
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	3,627,409	3,610,743
Assumed conversion of preferred stock warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	4,149,994	0
Assumed conversion of preferred stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	4,344,909	1,135,721
Assumed conversion of convertible notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	488,031	488,031
Stock options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	4,183,232	2,235,052

Net Loss per Share - Additional

Net Loss per Share - Additional Information (Details)	3 Months Ended
	Dec. 31, 2023 shares
Earnings Per Share [Abstract]
Pre-funded penny warrants outstanding	1,037,792

Net Loss per Share - Summary of

Net Loss per Share - Summary of Reconciliation of Weighted Average Shares Outstanding Calculation (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Weighted average shares issued (in shares)	15,039,630	8,290,529
Weighted average pre-funded warrants (in shares)	1,190,301	574,086
Weighted average number of basic shares outstanding (in shares)	16,229,931	8,864,615
Weighted average number of diluted shares outstanding (in shares)	16,229,931	8,864,615

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Thousands, € in Millions			12 Months Ended
	Jul. 05, 2023 USD ($)	Dec. 30, 2022 USD ($)	Dec. 31, 2023 USD ($)	Jan. 24, 2023 USD ($)	Oct. 12, 2021 EUR (€)	Apr. 30, 2021 EUR (€)
Loss Contingencies [Line Items]
Milestone payment unpaid | €					€ 1
Purchase obligation, option to extend, term			3 years
Purchase obligation, next fiscal year			$ 2,250
Medac
Loss Contingencies [Line Items]
Term over which the royalty is to be paid (in years)		5 years
Minimum annual payments		$ 200
Lachman
Loss Contingencies [Line Items]
Unpaid consulting fees				$ 900
Medac
Loss Contingencies [Line Items]
Accounts receivable | €						€ 1
Lachman
Loss Contingencies [Line Items]
Settlement amount	$ 900
Other Liabilities | Medac
Loss Contingencies [Line Items]
Loss contingency accrual			1,000
Other Noncurrent Liabilities | Medac
Loss Contingencies [Line Items]
Loss contingency accrual			800
Accrued Expenses | Medac
Loss Contingencies [Line Items]
Loss contingency accrual			$ 200

Subsequent Events (Details)

Subsequent Events (Details) $ / shares in Units, $ in Millions			12 Months Ended
	Mar. 19, 2024 USD ($)	Mar. 14, 2024 $ / shares shares	Dec. 31, 2023 $ / shares shares	Jan. 18, 2024 ft² $ / ft²	Jun. 30, 2023 $ / shares	Dec. 31, 2022 $ / shares
Subsequent Event [Line Items]
Number of shares sold (in shares) | shares			0
Common stock, par value (in dollars per share)			$ 0.01		$ 0.01	$ 0.01
Subsequent Event
Subsequent Event [Line Items]
Common stock, par value (in dollars per share)		$ 0.01
Warrant exercise price (in dollars per share)		$ 0.01
Subsequent Event | Private Placement
Subsequent Event [Line Items]
Gross proceeds from sale | $	$ 7
Subsequent Event | Private Placement | Common Stock
Subsequent Event [Line Items]
Number of shares sold (in shares) | shares		876,627
Purchase price (in dollars per share)		$ 3.72
Subsequent Event | Private Placement | Warrant
Subsequent Event [Line Items]
Number of shares sold (in shares) | shares		1,008,102
Purchase price (in dollars per share)		$ 3.71
Subsequent Event | Queensbury Lease
Subsequent Event [Line Items]
Area of space | ft²				18,000
Lease term				5 years
Extension term				5 years
Initial term commencement period				90 days
Annual base rent (in USD per sq ft) | $ / ft²				8
Annual base rent increase percentage in years four and five				3%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating Loss Carryforwards [Line Items]
Income tax provision	$ 0	$ 0
Percentage of valuation allowance against deferred tax assets	100%
Increase in deferred tax assets valuation allowance	$ 7,000	9,200
New York State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards net, expected to expire unutilized and unavailable to offset future federal taxable income	191,100
New York City
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards net, expected to expire unutilized and unavailable to offset future federal taxable income	175,400
Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	290,400	307,600
Operating loss carryforwards, annual limitation	28
Operating loss carryforwards net, expected to expire unutilized and unavailable to offset future federal taxable income	200,500
Operating loss carryforwards available for offset future taxable income	107,100
Operating loss carryforwards for unlimited period	105,400
Federal | Research and Development Tax Credit Carryforwards
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards	7,400	6,500
Tax credit carryforwards expected to expire unutilized	2,300
Federal | Expire Between 2019 and 2037
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards available for offset future taxable income	1,700
State and City
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	5,000	4,900
State | Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	800
State | Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	196,000
City | Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	300
City | Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	195,300
Foreign
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 43,300	$ 33,400

Income Taxes - Schedule of Loss

Income Taxes - Schedule of Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Domestic	$ (41,303)	$ (34,547)
Foreign	(6,375)	(1,960)
Income before taxes	$ (47,678)	$ (36,507)

Income Taxes - Income Tax Recon

Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Provision for income taxes [Abstract]
Income taxes using U.S federal statutory rate	$ (10,012)	$ (7,666)
Nondeductible interest	127	139
Branch income	(1,230)	(385)
State income taxes, net of federal benefit	(31)	(531)
Foreign rate differential	506	165
Valuation allowance	7,099	9,221
Stock option expense, exercises and cancellations	2,899	752
Research and development costs	(859)	(708)
Other	(179)	(987)
Derivative Charge	1,680	0
Total	$ 0	$ 0

Income Taxes - Significant Comp

Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Employee compensation accruals	$ 1,377	$ 2,772
Accrued liabilities	54	197
Research tax credits	2,330	1,429
Lease obligation	4	38
Other	233	160
Research expense capitalization	5,441	3,203
Net operating losses	29,875	24,595
Total deferred tax assets	39,314	32,394
Deferred tax liabilities:
Right of use asset	13	50
Total deferred tax liabilities	13	50
Valuation allowance	39,301	32,344	$ 23,125
Net deferred tax assets	$ 0	$ 0

Income Taxes - Summary of Chang

Income Taxes - Summary of Change in Valuation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Change in Deferred Tax Assets [Roll Forward]
Beginning Balance	$ 32,344	$ 23,125
Charged to costs and expenses	7,099	9,221
Charged to other comprehensive income	(142)	(2)
Ending balance	$ 39,301	$ 32,344

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measurements Using Significant Unobservable Inputs (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,280
Fair value of warrant liabilities issued	4,940
Total change in exchange rate	46
Fair value adjustment	1,358
Change due to warrant exercise	(1,080)
Ending balance	$ 6,544
Fair value adjustment, location	Fair value adjustment
Contingent Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,280
Fair value of warrant liabilities issued	0
Total change in exchange rate	46
Fair value adjustment	(330)
Change due to warrant exercise	0
Ending balance	996
Warrant Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0
Fair value of warrant liabilities issued	4,940
Total change in exchange rate	0
Fair value adjustment	1,688
Change due to warrant exercise	(1,080)
Ending balance	$ 5,548

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Warrant liability fair value adjustment	$ 7,998	$ 0

Fair Value Measurements - Fai_2

Fair Value Measurements - Fair Value Assumptions (Details) - Option pricing model - Preferred And Common Warrants	Dec. 31, 2023	Mar. 29, 2023
Risk free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input	0.0409
Risk free interest rate | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input		3.80
Risk free interest rate | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input		4.80
Expected term (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants, expected term	2 years 3 months 18 days
Expected term (years) | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants, expected term		6 months
Expected term (years) | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants, expected term		3 years
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input	0.70
Expected volatility | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input		70
Expected volatility | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input		75
Expected dividends
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input	0	0

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of the Company's Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets:
Total Assets	$ 20,200	$ 0
Liabilities:
Contingent Liability	996	1,280
Warrant Liability	5,548	0
Total Liabilities	6,544	1,280
Money market funds
Assets:
Total Assets	392	0
U.S. government agency bonds
Assets:
Total Assets	19,808	0
Level 1
Assets:
Total Assets	392	0
Liabilities:
Contingent Liability	0	0
Warrant Liability	0	0
Total Liabilities	0	0
Level 1 | Money market funds
Assets:
Total Assets	392	0
Level 1 | U.S. government agency bonds
Assets:
Total Assets	0	0
Level 2
Assets:
Total Assets	19,808	0
Liabilities:
Contingent Liability	0	0
Warrant Liability	0	0
Total Liabilities	0	0
Level 2 | Money market funds
Assets:
Total Assets	0	0
Level 2 | U.S. government agency bonds
Assets:
Total Assets	19,808	0
Level 3
Assets:
Total Assets	0	0
Liabilities:
Contingent Liability	996	1,280
Warrant Liability	5,548	0
Total Liabilities	6,544	1,280
Level 3 | Money market funds
Assets:
Total Assets	0	0
Level 3 | U.S. government agency bonds
Assets:
Total Assets	$ 0	$ 0