International Stem Cell (ISCO) 10-K 28 Mar 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2023	Mar. 25, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Title of 12(g) Security	Common Stock, $0.001 par value per share
Entity Registrant Name	INTERNATIONAL STEM CELL CORPORATION
Entity Central Index Key	0001355790
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well Known Seasoned Issuer	No
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Entity File Number	0-51891
Entity Tax Identification Number	20-4494098
Entity Address, Address Line One	9745 Businesspark Ave
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92131
City Area Code	760
Local Phone Number	940-6383
Entity Public Float			$ 481,068
Entity Common Stock, Shares Outstanding		8,004,389
Entity Incorporation, State or Country Code	DE
Entity Interactive Data Current	Yes
Document Annual Report	true
Document Transition Report	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction	false
Auditor Name	BDO USA, P.C.
Auditor Location	San Diego, California
Auditor Firm ID	243
Documents Incorporated by Reference	Information from portions of the registrant’s definitive Proxy Statement for its Annual Meeting of Stockholders to be held in 2024 is incorporated by reference into Part III of this Form 10-K.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash	$ 1,588	$ 742
Accounts receivable, net	574	747
Inventories	1,263	1,384
Prepaid expenses and other current assets	96	90
Total current assets	3,521	2,963
Non-current inventories	266	286
Property and equipment, net	215	248
Intangible assets, net	800	878
Right-of-use assets	557	727
Deposits and other assets	31	33
Total assets	5,390	5,135
Current liabilities:
Accounts payable	364	322
Accrued liabilities	485	508
Operating lease liabilities, current	276	230
Advances	250	250
Related party note payable	$ 3,457	$ 3,325
Notes Payable, Current, Related Party, Type [Extensible Enumeration]	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember
Total current liabilities	$ 4,832	$ 4,635
Operating lease liabilities, net of current portion	445	720
Total liabilities	5,277	5,355
Commitments and contingencies (Note 11)
Stockholders' Deficit:
Common stock, $0.001 par value; 120,000,000 shares authorized; 8,004,389 shares issued and outstanding at December 31, 2023 and December 31, 2022	8	8
Additional paid-in capital	106,276	105,812
Accumulated deficit	(110,476)	(110,345)
Total stockholders' deficit	(4,187)	(4,520)
Total liabilities, redeemable convertible preferred stock and stockholders' deficit	5,390	5,135
Series D Redeemable Convertible Preferred Stock [Member]
Current liabilities:
Series D redeemable convertible preferred stock, $0.001 par value; 50 share authorized; 43 shares issued and outstanding; liquidation preference of $4,300 at December 31, 2023 and December 31, 2022	4,300	4,300
Nonredeemable Convertible Preferred Stock [Member]
Stockholders' Deficit:
Non-redeemable convertible preferred stock, $0.001 par value; 10,004,310 and 10,004,310 shares authorized; 5,254,310 and 5,254,310 shares issued and outstanding; liquidation preference of $9,796 and $9,781 at December 31, 2023 and December 31, 2022, respectively	$ 5	$ 5

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Non-redeemable convertible preferred stock, par value	$ 0.001	$ 0.001
Non-redeemable convertible preferred stock, shares authorized	20,000,000	20,000,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	8,004,389	8,004,389
Common stock, shares outstanding	8,004,389	8,004,389
Series D Redeemable Convertible Preferred Stock [Member]
Temporary equity, par value	$ 0.001	$ 0.001
Temporary equity, shares authorized	50	50
Temporary equity, shares issued	43	43
Temporary equity, shares outstanding	43	43
Temporary equity, liquidation preference	$ 4,300	$ 4,300
Nonredeemable Convertible Preferred Stock [Member]
Non-redeemable convertible preferred stock, par value	$ 0.001	$ 0.001
Non-redeemable convertible preferred stock, shares authorized	10,004,310	10,004,310
Non-redeemable convertible preferred stock, shares issued	5,254,310	5,254,310
Non-redeemable convertible preferred stock, shares outstanding	5,254,310	5,254,310
Liquidation preference	$ 9,796	$ 9,781

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Product sales	$ 7,789	$ 8,180
Revenue, Product and Service [Extensible Enumeration]	Product [Member]	Product [Member]
Operating expenses:
Cost of sales	$ 3,181	$ 3,269
General and administrative	3,514	3,357
Selling and marketing	1,246	1,245
Research and development	511	492
Total operating expenses	8,452	8,363
Loss from operations	(663)	(183)
Other income (expense):
Employee retention credit	663
Interest expense	(139)	(135)
Other income (expense)	8	(13)
Total other income (expense), net	532	(148)
Net loss	$ (131)	$ (331)
Net loss per common share, basic	$ (0.02)	$ (0.04)
Net loss per common share, diluted	$ (0.02)	$ (0.04)
Weighted-average common shares used to compute net loss per share, basic	8,004,389	8,004,389
Weighted-average common shares used to compute net loss per share, diluted	8,004,389	8,004,389

Consolidated Statements of Chan

Consolidated Statements of Changes in Redeemable Convertible Preferred Stock and Stockholders' Deficit - USD ($) shares in Thousands, $ in Thousands	Total	Series D Redeemable Convertible Preferred Stock [Member]	Non-redeemable Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2021	$ (4,588)		$ 5	$ 8	$ 105,413	$ (110,014)
Beginning balance at Dec. 31, 2021		$ 4,300
Beginning balance, shares at Dec. 31, 2021			5,254	8,004
Stock-based compensation	399				399
Net loss	(331)					(331)
Ending balance at Dec. 31, 2022	(4,520)		$ 5	$ 8	105,812	(110,345)
Ending balance at Dec. 31, 2022		4,300
Ending balance, shares at Dec. 31, 2022			5,254	8,004
Stock-based compensation	464				464
Net loss	(131)					(131)
Ending balance at Dec. 31, 2023	$ (4,187)		$ 5	$ 8	$ 106,276	$ (110,476)
Ending balance at Dec. 31, 2023		$ 4,300
Ending balance, shares at Dec. 31, 2023			5,254	8,004

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	$ (131)	$ (331)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	194	218
Non-cash operating lease expense	170	141
Stock-based compensation	464	399
Interest expense on related party note payable	132	132
Changes in operating assets and liabilities:
Accounts receivable	173	97
Inventories	141	(114)
Prepaid expenses and other current assets	(6)	45
Deposits and other assets	2	6
Accounts payable	42	(186)
Accrued liabilities	(23)	104
Operating lease liabilities	(229)	(179)
Net cash provided by operating activities	929	332
Cash flows from investing activities
Purchases of property and equipment	(80)	(1)
Payments for patent licenses	(3)	(10)
Net cash used in investing activities	(83)	(11)
Cash flows from financing activities
Proceeds from note payable from a related party		250
Net cash provided by financing activities		250
Net increase in cash	846	571
Cash, beginning of period	742	171
Cash, end of period	1,588	742
Supplemental disclosure of cash flow information:
Cash paid for interest	6	3
Supplemental disclosure of non-cash investing activities:
Patent license costs included in accounts payable and accrued expense	$ 1	$ 2

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Summary of Significant Accounting Policies	1. Description of Business and Summary of Significant Accounting Policies Description of Business International Stem Cell Corporation (the “Company”) was organized in Delaware in June 2005 and is publicly traded on the OTCQX under the symbol “ISCO”. The Company is primarily a research and development company, for the therapeutic market, which has focused on advancing potential clinical applications of human parthenogenetic stem cells (“hpSCs”) for the treatment of various diseases of the central nervous system and liver diseases. The Company has the following wholly owned subsidiaries: • Lifeline Cell Technology, LLC (“LCT”) – for the biomedical market, develops, manufactures and commercializes primary human cell research products including over 200 human cell culture products, including frozen human “primary” cells and the reagents (called “media”) needed to grow, maintain and differentiate the cells; • Lifeline Skin Care, Inc. (“LSC”) – for the anti-aging market, develops, manufactures and markets a category of anti-aging skin care products based on the Company’s proprietary parthenogenetic stem cell technology and small molecule technology; • Cyto Therapeutics Pty. Ltd. (“Cyto Therapeutics”) – performs research and development (“R&D”) for the therapeutic market and is currently conducting clinical trials in Australia for the use of ISC-hpNSC® in the treatment of Parkinson’s disease. Liquidity and Going Concern The Company had an accumulated deficit of approximately $ 110.5 million as of December 31, 2023 and has historically incurred net losses and negative operating cash flows. The Company has had no revenue from its principal operations in therapeutic and clinical product development through research and development efforts. Unless the Company obtains additional financing, the Company does not have sufficient cash on hand to sustain operations for at least one year from the issuance date of these consolidated financial statements. There can be no assurance that the Company will be successful in maintaining normal operating cash flow or obtaining additional funding. These circumstances raise substantial doubt about the Company’s ability to continue as a going concern. For the foreseeable future, the Company’s ability to continue its operations is dependent upon its ability to obtain additional financing. The accompanying consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from the outcome of the uncertainty concerning the Company’s ability to continue as a going concern. The Company continues to evaluate various financing sources and options to raise working capital to help fund current research and development programs and operations. The Company will need to obtain significant additional funding from sources, including debt and/or equity financing, license arrangements, grants and/or collaborative research arrangements to sustain its operations and develop products. The timing and degree of any future capital requirements will depend on many factors, including: • the accuracy of the assumptions underlying the estimates for capital needs in 2024 and beyond; • the extent that revenues from sales of LSC and LCT products cover the related costs and provide capital; • scientific progress in research and development programs; • the magnitude and scope of the Company’s research and development programs and its ability to establish, enforce and maintain strategic arrangements for research, development, clinical testing, manufacturing and marketing; • the progress with preclinical development and clinical trials; • the extent to which third party interest in Company’s research and commercial products can be realized through effective partnerships; • the time and costs involved in obtaining regulatory approvals; • the costs involved in preparing, filing, prosecuting, maintaining, defending and enforcing patent claims; • the number and type of product candidates that the Company decides to pursue; and • the development of major public health concerns, such as the novel coronavirus outbreak, or other pandemics arising globally, and the current and future impact that such concerns may have on the Company’s operations and funding requirements. Additional debt financing may be expensive and require the Company to pledge all or a substantial portion of its assets. If additional funds are obtained through arrangements with collaborative partners, these arrangements may require the Company to relinquish rights to some of its technologies, product candidates or products that the Company would otherwise seek to develop and commercialize on its own. Furthermore, if sufficient capital is not available, the Company may be required to delay, reduce the scope of or eliminate one or more of its product initiatives. The Company’s failure to raise capital or enter into applicable arrangements when needed would have a negative impact on its financial condition. Principles of Consolidation and Foreign Currency Transactions The consolidated financial statements include the accounts of International Stem Cell Corporation and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The functional currency of the Company and its subsidiaries, including its wholly owned Australian subsidiary, Cyto Therapeutics, is the U.S. dollar. Assets and liabilities that are not denominated in the functional currency are remeasured into U.S. dollars at foreign currency exchange rates in effect at the respective balance sheet dates. Revenue and expenses are translated at the average rate in effect on the date of the transaction. Net realized and unrealized gains and losses from foreign currency transactions and remeasurement are reported in general and administrative expense in the accompanying consolidated statements of operations and were not material for the periods presented. Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying consolidated financial statements. Significant estimates include patent life (remaining legal life versus remaining useful life), allowance for excess and obsolete inventories, and stock option awards using the Black-Scholes option valuation model. Actual results could differ from those estimates. Segments The Company’s chief operating decision-maker reviews financial information presented on a consolidated basis, accompanied by disaggregated information by each reportable company’s statement of operations. The Company operates the business on the basis of three reporting segments, the parent company and two business units: ISCO – therapeutic market; LCT – biomedical market; and LSC – anti-aging market. Inventories Inventories are accounted for using the average cost and first-in, first-out (“FIFO”) methods for LCT cell culture media and reagents, average cost and specific identification methods for LSC products, and specific identification method for other LCT products. Inventories are stated at the lower of cost or net realizable value. Laboratory supplies used in the research and development process are expensed as consumed. LCT’s inventories have a long product life cycle, do not have a shelf life when frozen, and future demand is uncertain. As such, at each reporting period, the Company estimates its reserve for allowance for excess and obsolete inventory using historical sales data and inventory turnover rates. The establishment of a reserve for excess and obsolete inventory establishes a new cost basis of inventories. If the Company is able to sell such inventories, any related reserves would be reduced in the period of sale. The value of inventories that are not expected to be sold within one year of the current reporting period is classified as non-current inventories on the accompanying consolidated balance sheets. Accounts Receivable Trade accounts receivable are recorded at the net invoice value and are not interest bearing. Accounts receivable primarily consist of trade accounts receivable from the sales of LCT’s products, timing of cash receipts by the Company related to LSC credit card sales to customers, as well as LSC trade receivable amounts related to spa and distributor sales. The Company measures expected credit losses for financial instruments at each reporting date based on historical experience, current conditions, and reasonable forecasts. The allowance for credit losses represents the Company's estimate of expected credit losses relating to these factors. Amounts are written off against the allowances for credit losses when the Company determines that a customer account is uncollectible. As of both December 31, 2023 and 2022 , the Company's allowance for credit losses was immaterial. Advances In June 2008, the Company entered into an agreement with BioTime, Inc. (“BioTime”), whereby BioTime paid an advance of $ 250 thousand to LCT to produce, make, and distribute certain products. The $ 250 thousand advance will be paid down with the first $ 250 thousand of net revenues that otherwise would be allocated to LCT under the agreement. As of December 31, 2023 , no revenues were realized and attributable to BioTime under this agreement. Property and Equipment Property and equipment are stated at cost. The provision for depreciation and amortization is computed using the straight-line method over the estimated useful lives of the assets, which are generally three to five years . Leasehold improvements are capitalized and amortized over the shorter of the remaining term of the lease or the estimated life of the assets. Intangible Assets Intangible assets consist of acquired patent licenses and capitalized legal fees related to the acquisition, filing, maintenance, and defense of patents and trademarks. Amortization begins once the patent is issued by the appropriate authoritative bodies. In the period in which a patent application is rejected or efforts to pursue the patent are abandoned, all the related accumulated costs are expensed. Patents and other intangible assets are amortized on a straight-line basis over the shorter of the useful life of the underlying patent, which is generally 15 years, or when the intangible asset is rejected or abandoned. All amortization expense and impairment charges related to intangible assets are included in general and administrative expense in the accompanying consolidated statements of operations. Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in right-of-use assets, operating lease obligations, current, and operating lease obligations, net of current portion, on the Company’s consolidated balance sheets. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the present value of future minimum lease payments over the lease term. As the Company’s leases do not provide an implicit rate, the Company uses a discount rate based on its estimated incremental borrowing rate to determine the right-of-use asset and operating lease liabilities to be recognized. The Company determines its incremental borrowing rate based on the terms and lease payments of its operating leases and what it would normally pay to borrow, on a collateralized basis, over similar terms for an amount equal to the lease payments. Operating lease expense is recognized on a straight-line basis over the lease term. In addition, the Company does not separate lease components from non-lease components. Long-Lived Asset Impairment The Company reviews long-lived assets for impairment when events or changes in circumstances (“triggering event”) indicate that the carrying value of an asset or group of assets may not be recovered. If a triggering event is determined to have occurred, the carrying value of an asset or group of assets is compared to the future undiscounted cash flows expected to be generated by the asset or group of assets. If the carrying value exceeds the undiscounted cash flows of the asset or group of assets, then impairment exists. Fair value is generally determined using the asset’s expected future discounted cash flows or market value, if readily determinable. Revenue Recognition The Company's revenue consists primarily of sales of products from its two revenue-generating operating segments: the biomedical products market and anti-aging products market. The biomedical market segment markets and sells primary human cell research products with two product categories, cells and media, which are sold both domestically within the United States and internationally. The anti-aging market segment markets and sells a line of skincare products directly to customers through online orders via the ecommerce sales channel. The following table presents the Company’s revenue disaggregated by segment, product and geography (in thousands, except percentages): Biomedical market: Year Ended December 31, 2023 Total % of Total Domestic International Revenues Revenues Biomedical products Media $ 4,059 $ 683 $ 4,742 69 % Cells 1,602 522 2,124 31 % Total $ 5,661 $ 1,205 $ 6,866 100 % Year Ended December 31, 2022 Total % of Total Domestic International Revenues Revenues Biomedical products Media $ 4,572 $ 618 $ 5,190 73 % Cells 1,442 499 1,941 27 % Total $ 6,014 $ 1,117 $ 7,131 100 % Anti-aging market: Year Ended December 31, 2023 2022 Skin care products $ 923 $ 1,049 Contract terms for unit price, quantity, shipping and payment are governed by sales agreements, invoices or online order forms which the Company considers to be a customer's contract in all cases. The unit price is considered the observable stand-alone selling price for the arrangements. Any promotional or volume sales discounts are applied evenly to the units sold for purposes of calculating standalone selling price. The Company recognizes revenue when its customer obtains control of the promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. Product sales generally consist of a single performance obligation that the Company satisfies at a point in time (i.e., upon shipment of the product). For LSC products, online sales and professional sales are pre-paid through credit card charges. The Company sometimes extends 15, 30, or 60-day credit terms to select professional accounts. For biomedical products, standard payment terms for its customers are generally 30 days after the Company satisfies the performance obligation(s). For LSC, the Company honors a 30-day return policy, but historical returns have been minimal and as such, no estimated allowance for sales returns was recorded as of December 31, 2023 and 2022. The Company accounts for shipping and handling costs, recognized as cost of sales, as activities to fulfill the promise to transfer the goods to a customer. As a result, no consideration is allocated to shipping and handling costs. Rather, the Company accrues the cost of shipping and handling upon shipment of the product, and all contract revenue (i.e., the transaction price) is recognized at the same time. Variable Consideration The Company records revenue from customers in an amount that reflects the transaction price it expects to be entitled to after transferring control of those goods or services. From time to time, the Company offers sales promotions on its skincare products such as discounts and free product offers. Variable consideration is estimated at contract inception only to the extent that it is probable that a significant reversal of revenue will not occur and updated at the end of each reporting period as additional information becomes available. Contract Balances The Company records a receivable when it has an unconditional right to receive consideration after a performance obligation is satisfied. The opening and closing balances of accounts receivable, net for the year ended December 31, 2023 was $ 747 thousand and $ 574 thousand, respectively. The opening and closing balances of accounts receivable, net for the year ended December 31, 2022 was $ 844 thousand and $ 747 thousand, respectively. For the years ended December 31, 2023 and 2022 , the Company did no t incur material write-offs of its receivables. Practical Expedients The Company has elected the practical expedient to not determine whether contacts with customers contain significant financing components. The Company pays commissions on certain sales for its biomedical and anti-aging product markets once the customer payment has been received, which are accrued at the time of the sale. The Company generally expenses sales commissions when incurred because the amortization period would have been one year or less. These costs are recorded within sales and marketing expenses. In addition, the Company has elected to exclude sales taxes consideration from the determined transaction price. Allowance for Sales Returns The Company’s anti-aging products have a 30 -day product return guarantee; however, the Company determined that there is a low probability that returns will occur based on its historical rate of returns. Historically, returns have not been significant and are recognized as a reduction to current period revenue. As of December 31, 2023 and 2022 , the Company recorded no allowance for sales returns. Cost of Sales Cost of sales consists primarily of salaries and benefits associated with employee efforts expended directly on the production of the Company’s products, as well as related direct materials, general laboratory supplies and an allocation of overhead. Certain of the Company’s licensed technology agreements may require the Company to pay royalties based on the future sale of the Company’s products. Such royalties will be recorded as a component of cost of sales when incurred. Additionally, milestone payments or the amortization of license fees related to developed technologies used in the Company’s products will be included as a component of cost of sales to the extent that such payments become due in the future. Advertising Adverting costs are expensed as incurred and included as a component of selling and marketing costs on the accompanying consolidated statements of operations. For the years ended December 31, 2023 and 2022, advertising costs were approximately $ 204 thousand and $ 220 thousand, respectively. Research and Development Costs Research and development costs, which are expensed as incurred, primarily consist of salaries and benefits associated with research and development personnel, overhead and occupancy costs, contract services costs and amortization of license costs for technology used in research and development without alternative future uses, offset by the research and development tax credits provided by the Australian Taxation Office for qualified expenditures. Australian Research and Development Tax Credit The Company’s wholly owned subsidiary, Cyto Therapeutics, conducts various research and development activities on the Company’s product candidates in Australia. Under Australian tax law, the Australian Taxation Office provides for a refundable tax credit in the form of a cash refund equal to 43.5 % of qualified research and development expenditures, not to exceed established thresholds. The Australian Research and Development tax incentive program is a self-assessment process, and the Australian Government has the right to review the Company’s qualifying programs and related expenditures for a period of four years. If such a review were to occur and, as a result of the review and failure of a related appeal, the qualified program and related expenditures were disqualified, the respective research and development refunds could be recalled with penalties and interest. The refundable tax credit does not depend on the Company’s generation of future taxable income or ongoing tax status or position. Accordingly, the credit is not considered an element of income tax accounting under FASB Accounting Standards Codification (“ASC”) 740 – Income Taxes. The Company uses the grant accounting model by analogy to International Accounting Standards (“IAS”) 20 to account for the refundable tax credit from the Australian government. The Company recognizes the research and development tax credit as a reduction to research and development expense when there is reasonable assurance that the tax credit will be received, the relevant expenses have been incurred, and the amount can be reliably measured. During the year ended December 31, 2023 and 2022, the Company recognized a reduction in research and development expenses of $ 99 thousand and $ 80 thousand, respectively, within research and development expense on the accompanying consolidated statement of operations. As of December 31, 2023 and 2022 , the Company recognized a research and development tax credit receivable of zero and $ 80 thousand, respectively, within prepaid expenses and other current assets on the accompanying consolidated balance sheet. Employee Retention Credit Similar to the Australian Research and Development tax credit, the Company uses the grant accounting model by analogy to IAS 20 to account for the refundable Employee Retention Tax Credit (“ERC”) from the U.S. government. The Company recognized the refundable tax credit as other income when there was reasonable assurance that the tax credit will be received, the relevant expenses have been incurred, and the amount can be reliably measured. Laws and regulations concerning government programs, including the ERC, are complex and subject to varying interpretations. Claims made under these programs may also be subject to retroactive audit and review. While the Company does not believe there is a basis for estimation of an audit or recapture risk at this time, there can be no assurance that regulatory authorities will not challenge the Company’s claim to the ERC in a future period. Refer to Note 8 – Employee Retention Credit within the consolidated financial statements for further discussion. Stock-Based Compensation The cost of a stock-based award is measured at the grant date based on the estimated fair value of the award, and is recognized as expense on a straight-line basis, net of forfeitures which are recognized as incurred, over the requisite service period of the award. The fair value of stock options is estimated using the Black-Scholes option valuation model, which requires the input of subjective assumptions, including price volatility of the underlying stock, risk-free interest rate, dividend yield, and expected life of the option. The Company uses the Simplified Method to estimate the term of options granted. The fair value of restricted stock awards is based on the market value of the Company’s common stock on the date of grant. Fair Value Measurements The carrying amounts of the Company’s accounts receivable, accounts payable, and accrued liabilities are considered to be representative of their respective fair values because of the short-term nature of those instruments. The carrying value of the Company's related party note payable does not approximate fair value. Refer to Note 10 – Related Party Transactions within the consolidated financial statements for further discussion. Income Taxes The Company uses the asset and liability method of accounting for income taxes. When the Company prepares its consolidated financial statements, it estimates income taxes based on the various jurisdictions and countries where it conducts business. This requires the Company to estimate current tax exposure and to assess temporary differences that result from differing treatments of certain items for tax and accounting purposes. Deferred income taxes are recognized based on the differences between the financial statement and income tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The Company then assesses the likelihood that deferred tax assets will be realized. Valuation allowances are established, when it is more likely than not the deferred tax assets will not be realized. When the Company establishes a valuation allowance or increases this allowance in an accounting period, it records a corresponding tax expense in the consolidated statements of operations. The Company includes interest and penalties related to income taxes within its provision for income taxes. Net Loss Per Share Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per share attributable to common stockholders is computed by dividing the net income attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury and two-class or "if-converted" methods. The two-class method is not applicable during periods with a net loss, as the holders of the convertible preferred stock do not have an obligation to fund losses. Potentially dilutive common stock equivalents are comprised of stock options and convertible preferred stock. For the years ended December 31, 2023 and 2022, there was no difference in the number of shares used to calculate basic and diluted shares outstanding as the Company was in a net loss position. For the years ended December 31, 2023 and 2022, the following common stock options and convertible preferred stock were not included in the diluted net loss per share calculation because the effect would be anti-dilutive. Year Ended December 31, 2023 2022 Employee stock options 8,590,455 6,460,654 Redeemable convertible preferred stock 2,457,143 2,457,143 Non-redeemable convertible preferred stock 5,061,687 3,619,379 Total 16,109,285 12,537,176 Comprehensive Loss Comprehensive loss includes all changes in stockholders’ deficit except those resulting from investments by owners and distributions to owners. The Company did not have any items of comprehensive loss other than net loss from operations for the years ended December 31, 2023 and 2022 . Customer Concentrations For the years ended December 31, 2023 and 2022 , one customer accounted for approxim ately 46 % and 45 % , respectively, of consolidated product sales, and approximately 52 % and 51 %, respectively, of biomedical product sales. As of December 31, 2023 and 2022, the same customer accounted for 47 % and 73 % , respectively, of accounts receivable, net. No other single customer accounted for more than 10% of product sales, net for the years ended December 31, 2023 and 2022 in either segment. As of December 31, 2023 , three customers individually accounted for more than 10 % of accounts receivable, net and in the aggregate, accounted for 33 % of accounts receivable, net. No other single customer accounted for more than 10% of accounts receivable, net as of December 31, 2022 . Recently Issued Accounting Pronouncements In August 2020, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity (“ASU 2020-06”). ASU 2020-06 intends to simplify the accounting for convertible debt instruments by reducing the number of accounting models and the number of embedded features that could be recognized separately from the host contract. Among other things, the amendment allows certain convertible debt instruments to be accounted for as a single liability measured at its amortized cost, as long as no other features require bifurcation and recognition as derivatives. Further, the amendments require use of the if-converted method in the diluted earnings per share calculation for convertible instruments. The new standard will be effective for the Company on January 1, 2024. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements and related disclosures. In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosure s (“ASU 2023-07”). ASU 2023-07 intends to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. Among other things, the amendments in ASU 2023-07 require additional information regarding significant segment expenses provided to the chief operating decision maker (“CODM”), qualitative and quantitative disclosures regarding other segment items, any additional segment profit or loss measures contemplated by the CODM when assessing segment performance, how the CODM allocates resources among segments, and the title and position of the CODM. Further, the amendments require interim segment reporting disclosures that were previously only required to be disclosed annually. ASU 2023-07 will be effective for the Company for the fiscal year ending December 31, 2024 and for interim periods beginning January 1, 2025. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosure (“ASU 2023-09”). ASU 2023-09 intends to provide improved transparency about income tax information through improvements to income tax disclosures. Among other things, the amendments in ASU 2023-09 require enhanced disclosures regarding federal, state, and foreign income taxes primarily related to the income tax rate reconciliation and income taxes paid. Further, the amendments eliminate certain disclosure requirements related to uncertain tax positions and unrecognized deferred tax liabilities. The new standard will be effective for the Company for the fiscal year ending December 31, 2025. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements and related disclosures. Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). The ASU introduced a new credit loss methodology, the Current Expected Credit Losses (“CECL”) methodology, which requires earlier recognition of credit losses, while also providing additional transparency about credit risk. The CECL methodology utilizes a lifetime “expected credit loss” measurement objective for the recognition of credit losses for loans, held-to maturity debt securities, trade receivables and other receivables measured at amortized cost at the time the financial asset is originated or acquired. Subsequent to the issuance of ASU 2016-13, the FASB issued several additional ASUs to clarify implementation guidance, provide narrow-scope improvements and provide additional disclosure guidance. The Company adopted ASC 2016-13 on January 1, 2023 . The adoption of this standard did no t have a material impact on the Company's consolidated financial statements.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Inventories	2. Inventories The components of inventories are as follows (in thousands): December 31, 2023 2022 Raw materials $ 526 $ 615 Work in process 597 498 Finished goods 1,145 1,194 2,268 2,307 Less: allowance for inventory excess and obsolescence ( 739 ) ( 637 ) Total inventories $ 1,529 $ 1,670 Inventories $ 1,263 $ 1,384 Non-current inventories 266 286 Total inventories $ 1,529 $ 1,670 As of December 31, 2023 and 2022, the allowance for inventory excess and obsolescence consists of the following activity (in thousands): December 31, 2023 2022 Balance, beginning of year $ 637 $ 526 Provision for inventory reserve 277 218 Write-offs ( 175 ) ( 107 ) Balance, end of year $ 739 $ 637 The write-offs include scrapped inventories and reserved inventories sold.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property and Equipment	3. Property and Equipment Property and equipment consist of the following (in thousands): December 31, 2023 2022 Machinery and equipment $ 1,602 $ 1,603 Computer equipment and software 221 217 Office equipment 89 89 Leasehold improvements 617 558 Construction in progress 12 — 2,541 2,467 Less: accumulated depreciation and amortization ( 2,326 ) ( 2,219 ) Property and equipment, net $ 215 $ 248 Depreciation and amortization expense for the years ended December 31, 2023 and 2022 was $ 112 thousand and $ 137 thousand. During the year ended December 31, 2023 and 2022, the Company disposed of approximately $ 5 thousand and $ 41 thousand, respectively, in property and equipment that had been depreciated and amortized in full and had no impact on the accompanying consolidated statements of operations.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	4. Intangible Assets Intangible Assets consists of the following (in thousands): December 31, 2023 2022 Patents $ 1,290 $ 1,286 Less: accumulated amortization ( 565 ) ( 483 ) 725 803 Indefinite life logos and trademarks 75 75 Intangible assets, net $ 800 $ 878 Amortization expense for the years ended December 31, 2023 and 2022 was $ 82 thousand and $ 81 thousand, respectively. No impairment charges were recorded for the years ended December 31, 2023 and 2022. The timing of approval of pending patent applications is uncertain and, therefore, are included in the thereafter period below until issued. Pending patents as of December 31, 2023 and 2022 was $ 61 thousand and $ 57 thousand. As of December 31, 2023, future amortization expense related to intangible assets subject to amortization is expected to be as follows (in thousands): Years ending December 31, 2024 $ 82 2025 80 2026 76 2027 73 2028 73 Thereafter 341 Total $ 725

Convertible Preferred Stock

Convertible Preferred Stock	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Convertible Preferred Stock	5. Convertible Preferred Stock As of December 31, 2023 and 2022, the Company was authorized to issue 20,000,000 shares of preferred stock , $ 0.001 par value per share. The Company has designated 50 shares of Series D redeemable convertible preferred stock and as of both December 31, 2023 and 2022, a total of 10,004,310 of Series B, Series G and Series I-2 non-redeemable convertible preferred stock. The Company’s Series B, Series G and Series I-2 non-redeemable convertible preferred stock has been classified as equity on the accompanying consolidated balance sheets. The authorized, issued and outstanding shares of non-redeemable convertible preferred stock as of December 31, 2023 consist of the following: Shares Shares Issued and Liquidation Carrying Authorized Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 486 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-2 4,310 4,310 4,310 — Total 10,004,310 5,254,310 $ 9,796 $ 5 The authorized, issued and outstanding shares of non-redeemable convertible preferred stock as of December 31, 2022 consist of the following: Shares Shares Issued and Liquidation Carrying Authorized Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 471 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-2 4,310 4,310 4,310 — Total 10,004,310 5,254,310 $ 9,781 $ 5 The significant rights and preferences of the Company’s convertible preferred stock are as follows: Dividends Holders of the Company’s convertible preferred stock are entitled to participating dividends with common stock when and if declared by the Company’s Board of Directors. The Series D and G convertible preferred stock previously had rights to cumulative dividends in liquidation whether declared or not declared. Since the holders waived the rights to such dividends in prior years, this does not have an ongoing impact. No dividends have been declared for the year ended December 31, 2023. Liquidation Liquidation preference among classes of preferred shares is first with Series D with priority, followed by Series G, Series B and Series I-2 on the proceeds from any sale or liquidation of the Company in an amount equal to the purchase price of shares plus (in the case of the Series B) an amount equal to 1 % of the Series B original issue price for every two calendar months from February 1, 2008. Following the satisfaction of the liquidation preferences, all shares of common stock participate in any remaining distribution. Conversion The conversion rates of the Series B, Series D, and Series I-2 are subject to anti-dilution adjustments whereby, subject to specified exceptions, if the Company issues equity securities or securities convertible into equity at a price below the applicable conversion price of the Series B, Series D, and Series I-2, the conversion price of each such series shall be adjusted downward to equal the price of the new securities. The conversion rate of the Series G is subject to a weighted-average adjustment in the event of the issuance of additional shares of common stock below the conversion price, subject to specified exceptions. Upon the occurrence of an event that triggers a down round protection, the Company will recognize the value of the down round as a beneficial conversion discount. The conversion price of the Series I-2 are also subject to certain resets as set forth in the Certificates of Designation, including a reverse stock split. The following table summarizes the number of shares of common stock into which each share of convertible preferred stock can be converted as of December 31, 2023: Conversion Initial Current Ratio to Conversion Conversion Common Price Price Stock Series B $ 75.00 $ 0.12 8.33 Series D $ 37.50 $ 1.75 57,142.86 Series G $ 60.00 $ 9.69 0.10 Series I-2 $ 1.75 $ 1.75 571.43 Voting The holders of Series B, Series D, and Series G are entitled to one vote for each share of common stock into which it would convert. As long as there are at least 10 shares of Series D outstanding, the holders of Series D have (i) the right to nominate and elect two members of the Board of Directors, and (ii) the right to approve specified significant transactions affecting the Company. As long as there are at least 1,000,000 shares of Series G outstanding, the holders of Series G have the initial right to propose the nomination of two members of the Board, at least one of which such nominees shall be subject to the approval of the Company’s independent directors, for election by the stockholders at the Company’s next annual meeting of stockholders, or, elected by the full board of directors to fill a vacancy, as the case may be. At least one of the two directors nominated by holders of the Series G shall be independent. The holder of Series I-2 has no voting rights, except as required by law. Series D Preferred Stock Redemption The Company’s Series D redeemable convertible preferred stock contains a contingent redemption feature that is not solely within the Company’s control. Accordingly, the Series D redeemable convertible preferred stock is classified in temporary equity (outside of permanent equity) on the accompanying consolidated balance sheets.

Stockholders' Deficit

Stockholders' Deficit	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Stockholders' Deficit	6. Stockholders’ Deficit Common Stock As of December 31, 2023, the Company was authorized to issue 120,000,000 shares of common stock, $ 0.001 par value per share. Common Stock Reserved for Future Issuance As of December 31, 2023, the Company had shares of common stock reserved for future issuance as follows: Options outstanding 11,807,494 Common stock available for issuance under the 2010 Plan 18,025,564 Redeemable convertible preferred stock 2,457,143 Non-redeemable convertible preferred stock 5,061,687 Total 37,351,888

Equity Incentive Plans

Equity Incentive Plans	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Equity Incentive Plans	7. Equity Incentive Plans The Company adopted the 2006 Equity Participation Plan (as amended, the “2006 Plan”), which provides for the grant of stock options, restricted stock and other equity-based awards. Awards for up to 100,000 shares may be granted to employees, directors and consultants under this Plan. The options granted under the 2006 Plan may be either qualified or non-qualified options. Options may be granted with different vesting terms and expire no later than 10 years from the date of grant. The 2006 Plan expired on November 16, 2016 . Options and other equity-based awards granted prior to the expiration of the 2006 Plan will continue in effect until the option or award is exercised or terminates pursuant to its terms. No new awards may be granted under the 2006 Plan following its expiration. In April 2010, the Company adopted the 2010 Equity Participation Plan, as amended (“2010 Plan”), which provides for the grant of stock options, restricted stock and other equity-based awards. Awards for up to 9,700,000 shares may be granted to employees, directors and consultants under the 2010 Plan. The options granted under the 2010 Plan may be either qualified or non-qualified options. Options may be granted with different vesting terms and expire no later than 10 years from the date of grant. In June 2020, the Company amended the 2010 Plan to extend the term of the 2010 Plan until March 2030 . No other material provisions were amended. In September 2023, the Company's Board of Directors voted to amend the 2010 Plan (“2010 Plan Amendment”) to 1) increase the number of shares that may be issued under the 2010 Plan from 9,700,000 shares to an aggregate of 30,000,000 shares of common stock and 2) increase the number of awards an employee may receive in a calendar year from 800,000 shares to 10,000,000 shares. The majority shareholders approved the 2010 Plan Amendment on September 21, 2023 and the Company filed the Notice of Internet Availability of Information Statement (the “Notice”) on September 27, 2023, noting the 2010 Plan Amendment would become effective no earlier than 40 calendar days after the Notice was first made available to shareholders. Accordingly, on November 6, 2023, the 2010 Plan Amendment became effective. For the year ended December 31, 2023, there were no restricted stock units granted. As of December 31, 2023, there were no restricted stock units outstanding. Stock Options Transactions involving stock options issued to employees, directors and consultants under the 2006 Plan and the 2010 Plan are summarized below. Options issued have a maximum life of 10 years and no options were exercised in the years ended December 31, 2023 and 2022 . The following tables summarize the changes in options outstanding and the related exercise prices for the Company’s common stock options issued: Average Weighted- Remaining Aggregate Number of Average Contractual Intrinsic Outstanding Exercise Term Value Options Price (in years) (in thousands) Outstanding at December 31, 2022 6,858,492 $ 1.02 Granted 4,950,410 $ 0.13 Expired ( 1,408 ) $ 39.98 Outstanding at December 31, 2023 11,807,494 $ 0.64 7.75 $ — Vested and expected to vest at December 31, 2023 11,213,305 $ 0.67 7.66 $ — Exercisable at December 31, 2023 6,482,569 $ 1.01 6.41 $ — Stock-Based Compensation The weighted-average assumptions used in the Black-Scholes option valuation model to determine the fair value of stock options grants for the years ended December 31, 2023 and 2022 were as follows: Year Ended December 31, 2023 2022 Risk-free interest rate 4.28 % 2.86 % Expected stock price volatility 91.50 % 90.29 % Expected dividend yield 0 % 0 % Expected life of options (in years) 5.69 5.71 Weighted-average grant date fair value $ 0.10 $ 0.33 Total stock-based compensation expense for the years ended December 31, 2023 and 2022 was comprised of the following (in thousands): Year Ended December 31, 2023 2022 Cost of sales $ 3 $ 5 General and administrative 359 345 Selling and marketing 7 7 Research and development 95 42 Total $ 464 $ 399 Unrecognized compensation expense related to stock options as of December 31, 2023 was $ 650 thousand, which is expected to be recognized over a weighted-average period of approximately 1.84 years.

Employee Retention Credit

Employee Retention Credit	12 Months Ended
	Dec. 31, 2023
Employee Retention Credit [Abstract]
Employee Retention Credit	8. Employee Retention Credit Other income is primarily attributable to the one-time receipt of the Employee Retention Tax Credit from the Internal Revenue Service (the "IRS"). As a response to the COVID-19 outbreak, the U.S. government enacted the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”), which contained a number of programs to assist workers, families and businesses. Part of the CARES Act provides an Employee Retention Credit (“ERC”), which is a refundable tax credit against certain employment taxes equal to 50 % of qualified wages paid, up to $ 10,000 per employee annually, from March 12, 2020 through January 1, 2021. Additional relief provisions were passed by the United States government, which extended and expanded the qualified wage caps on these credits to 70 % of qualified wages paid through June 30, 2021 and 100 % of qualified wages paid through December 31, 2021, up to $ 10,000 per employee per quarter. In January 2023, the Company filed Form 941-X for the three months ended March 31, June 30 and September 30, 2021 to claim a refund for the ERC. The Company elected to account for the ERC under IAS 20 when there was reasonable assurance of receipt, which was determined to be when the notification of acceptance of Form 941-X was received by the IRS. In June 2023, the Company received confirmation from the IRS that changes to the Company’s Q1, Q2 and Q3 941 forms amounting to $ 224 thousand in the first quarter of 2021, $ 238 thousand in the second quarter of 2021, and $ 201 thousand in the third quarter of 2021 had been accepted. The Company received payment from the IRS related to the ERC during the second quarter of 2023 and recorded other income of $ 663 thousand in the accompanying consolidated statement of operations.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	9. Income Taxes Pre-tax loss consists of the following jurisdictions (in thousands): December 31, December 31, 2023 2022 Domestic pre-tax book loss $ ( 76 ) $ ( 228 ) Foreign pre-tax book loss ( 55 ) ( 103 ) Consolidated pre-tax book loss $ ( 131 ) $ ( 331 ) A reconciliation of the statutory federal income tax rate and the effective income tax rate for the years ended December 31, 2023 and 2022 is as follows: Year Ended December 31, 2023 2022 Statutory federal income tax rate 21.0 % 21.0 % State income taxes, net of federal taxes ( 68.0 %) ( 8.5 %) Foreign rate differentials 41.3 % 0.8 % Permanent items ( 9.2 %) ( 5.1 %) Change in valuation allowance 11,815.8 % 190.7 % Research and development tax credits limitation ( 1,241.0 %) 0.0 % Employee retention credit income 104.5 % 0.0 % Stock-based compensation ( 226.9 %) 8.0 % Adjustments to NOL ( 10,830.5 %) ( 40.6 %) ASC 740-10 adjustments 402.0 % ( 170.0 %) Other ( 9.0 %) 3.7 % Effective income tax rate 0.0 % 0.0 % The Company files income tax returns in the U.S. federal jurisdiction, and various states. With few exceptions, the Company is no longer subject to U.S. federal, state, and local income tax examinations by tax authorities for years before 2017. The Company follows the provisions of FASB ASC 740-10 – Accounting for Uncertainty in Income Taxes. ASC 740-10 prescribes a comprehensive model for the recognition, measurement, presentation and disclosure in consolidated financial statements of uncertain tax positions that have been taken or are expected to be taken on a tax return. As of December 31, 2023 and 2022, the Company's reserve for unrecognized tax benefits was approximately $ 478 thousand and $ 953 thousand, respectively. Due to the full valuation allowance as of December 31, 2023, current adjustments to the unrecognized tax benefits will have no impact on the Company's effective tax rate. The Company does not anticipate any significant changes in its unrecognized tax benefits within 12 months of this reporting date. For the years ended December 31, 2023 and 2022, there were no penalties or interest recognized related to unrecognized tax benefits given the Company's historical loss position and full valuation allowance. A reconciliation of the reserve for unrecognized tax benefits is as follows (in thousands): Balance as of December 31, 2021 $ — Increase (decrease) related to prior year tax positions 953 Increase (decrease) related to current year tax positions — Increase (decrease) related to settlements with taxing authorities — Increase (decrease) related to lapse in statute of limitations — Balance as of December 31, 2022 953 Increase (decrease) related to prior year tax positions ( 475 ) Increase (decrease) related to current year tax positions — Increase (decrease) related to settlements with taxing authorities — Increase (decrease) related to lapse in statute of limitations — Balance as of December 31, 2023 $ 478 As of December 31, 2023, the Company has available federal net operating loss (“NOL”) carryforwards of approximately $ 20.3 million, which may be applied against future taxable income and will expire in various years beginning 2026 through 2037 . However, any NOL carryforwards generated in 2018 and future tax years will not expire and are carried forward indefinitely. State NOL carryforwards will start to expire in 2036 . As of December 31, 2022, the Company had federal NOL carryforwards of approximately $ 73.5 million. The decrease in federal NOL carryforwards for the year ended December 31, 2023 is approximately $ 53.2 million, which is primarily attributable to the Internal Revenue Code (“IRC”) Section 382 limitation. As of December 31, 2023, the Company has Australian NOL carryforwards of approximately $ 1.0 million, which may be carried forward indefinitely. The amount of and ultimate realization of the benefits from NOL carryforwards for income tax purposes is dependent, in part, upon the tax laws in effect, the future earnings of the Company, and other future events, the effects of which cannot be determined at this time. Because of the uncertainty surrounding the realization of NOL carryforwards, the Company has established a valuation allowance equal to the tax effect of the NOL carryforwards, research and development (“R&D”) credits, and accruals; therefore, no net deferred tax asset has been recognized as of December 31, 2023. The Company is subject to IRC Sections 382 and 383, which limits the amount of NOL and tax credit carryovers that can be used in future years. The Company has completed a study to assess whether an ownership change has occurred, as defined by IRC Sections 382 and 383, or whether there have been ownership changes since the Company's formation. Based on the completed study, it was determined that the Company had significant ownership changes that occurred in January 2009 and November 2015. As a result of the ownership changes, under IRC Sections 382 and 383, the NOL and R&D tax credit carryforwards that were generated in the year prior to November 2015 have been significantly limited and a substantial unused amount will expire. The Company estimates that if another future change in ownership did occur, the federal and state NOL and R&D tax credit carryforwards that can be utilized in the future would be significantly limited as well. There can be no assurance that the Company will ever be able to realize the benefit of some or all of the federal and state NOL and R&D tax credit carryforwards, either due to ongoing operating losses or significant ownership change limitations. Significant components of deferred tax assets and liabilities are as follows (in thousands): December 31, December 31, 2023 2022 Deferred tax assets: Net operating loss carryforwards $ 5,476 $ 19,266 Research and development tax credits 922 1,993 Stock-based compensation 995 1,252 IRC Section 174 costs 172 95 Intangibles 166 191 Lease liabilities 161 224 Accrued expenses 123 128 Deferred tax assets 8,015 23,149 Less: valuation allowance ( 7,858 ) ( 22,936 ) Net deferred tax assets 157 213 Deferred tax liabilities: Right-of-use assets ( 125 ) ( 171 ) Depreciation ( 32 ) ( 42 ) Total deferred tax liabilities ( 157 ) ( 213 ) Net deferred tax assets $ — $ —

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2023
Related Party Transactions [Abstract]
Related Party Transactions	10. Related Party Transactions Related party lease agreements On October 26, 2021, the Company and S Real Estate Holdings, LLC jointly entered into a lease agreement with Rehco Holdings, LLC (the “Lease”), for the purpose of establishing a new corporate headquarters, including corporate, R&D, and manufacturing operations. S Real Estate Holdings LLC is owned by Dr. Russell Kern, the Company’s Executive Vice President and Chief Scientific Officer. The lease agreement was approved by the Board of Directors and was reviewed by the Company’s outside legal counsel. The terms of the lease were reviewed by a committee of independent directors, and the Company believes that, in total, those terms are at least as favorable to the Company as could be obtained for comparable facilities from an unaffiliated party. The Lease was personally guaranteed by the Dr. Russell Kern, the Company’s Executive Vice President and Chief Scientific Officer. On December 15, 2021, the Company and S Real Estate Holdings LLC entered into a co-tenant agreement, whereby the Company and S Real Estate Holdings LLC agreed to allocate portions of the base rent and variable charges, including insurance, maintenance costs, taxes and operating expenses, between the parties. During the term of the Lease, the Company will be liable for 40 % of all costs incurred in connection with the Lease, while S Real Estate Holdings LLC will be liable for the remaining 60 %. Refer to Note 11 – Commitments & Contingencies within the consolidated financial statements for further discussion. Related party note payable Between March 2018 and March 2021, to obtain funding for working capital purposes, the Company borrowed a total of $ 2.7 million from Dr. Semechkin and issued an unsecured, non-convertible promissory note in the principal amount of $ 2.7 million (the “Note”) to Dr. Semechkin. The outstanding principal amount under the Note accrued interest at a rate of 4.5 % per annum. The outstanding principal and accrued interest on the Note were due and payable on January 15, 2022 and could be pre-paid without penalty at any time. In January 2022, to obtain additional funding for working capital purposes, the Company further modified the Note and issued an unsecured, non-convertible promissory note (the “January 2022 Note”) in the amount of $ 2.9 million to Dr. Semechkin. In exchange, Dr. Semechkin surrendered the Note and provided additional funding in the amount of $ 250 thousand to the Company. The outstanding principal amount under the January 2022 Note accrues interest at a rate of 4.5 % per annum. The outstanding principal and accrued interest on the January 2022 Note were due and payable on March 15, 2022 and may be pre-paid by the Company without penalty at any time. In March 2022, the Noteholder surrendered the January 2022 Note, and the Company issued a new promissory note (“March 2022 Note”), which featured all the same terms as the previously outstanding note, with the exception of an extension of the maturity date from March 15, 2022 to September 15, 2022 . The March 2022 Note has a principal balance of $ 2.9 million, an interest rate of 4.5 %, and features optional prepayment terms. There were no debt issuance fees associated with this issuance. In September 2022, the Noteholder surrendered the March 2022 Note, and the Company issued a new promissory note (“September 2022 Note”), which featured all the same terms as the previously outstanding note, with the exception of an extension of the maturity date from September 15, 2022 to March 15, 2023 . The September 2022 Note has a principal balance of $ 2.9 million, an interest rate of 4.5 %, and features optional prepayment terms. There were no debt issuance fees associated with this issuance. In March 2023, the Noteholder surrendered the September 2022 Note, and the Company issued a new promissory note (“March 2023 Note”), which featured all the same terms as the previously outstanding note, with the exception of an extension of the maturity date from March 15, 2023 to September 15, 2023 . The March 2023 Note has a principal balance of $ 2.9 million, an interest rate of 4.5 %, and features optional prepayment terms. There were no debt issuance fees associated with this issuance. In September 2023, the Noteholder surrendered the March 2023 Note, and the Company issued a new promissory note (“September 2023 Note”), which featured all the same terms as the previously outstanding note, with the exception of an extension of the maturity date from September 15, 2023 to September 15, 2024 . The September 2023 Note has a principal balance of $ 2.9 million, accrues interest at 4.5 % per annum from the original borrowing date, and features optional prepayment terms. There were no debt issuance fees associated with this issuance. All amendments during the years ended December 31, 2023 and 2022 qualified as troubled debt restructurings, which did not result in a gain as the carrying amount of the debt was less than the total future cash payments of the restructured debt.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies Leases As of December 31, 2023 , the Company has three operating leases for real estate in California and Maryland: • San Diego, California – corporate headquarters, including corporate, R&D, and manufacturing operations, with a term date of December 2026 , jointly leased with a related party (refer to Note 10 – Related Party Transactions within the consolidated financial statements for further discussion); • San Diego, California – supplemental office space adjacent to the Company’s corporate headquarters with a term date of December 2026 ; and • Frederick, Maryland – mixed laboratory and administrative space with a term date of November 2025 . In October 2021, the Company entered into an operating lease for its new corporate headquarters. The lease commenced in November 2021 and expires on December 31, 2026 . At commencement, base rent due under the lease was approximately $ 11 thousand and increases approximately 3.5 % per annum over the lease term. The lease is subject to additional variable charges, including insurance, maintenance costs, taxes and operating expenses. Base rent and additional variable charges are shared between the Company and S Real Estate Holdings LLC, a related party, with base rent for months two through five of the lease term abated by 50 %. At lease commencement, the Company recognized a right-of-use asset and lease liabilities of approximately $ 232 thousand. In November 2021, the Company entered into an operating lease for supplemental office space adjacent to its new corporate headquarters with the same landlord. The lease commenced in December 2021 and expires on December 31, 2026 , and is not subject to the co-tenant agreement with S Real Estate Holdings, LLC. At commencement, base rent due under the supplemental office lease was approximately $ 4 thousand per month and increases at a fixed amount per annum over the lease term. At lease commencement, the Company recognized a right-of-use asset and lease liabilities of approximately $ 247 thousand. The Company’s operating leases for real estate are subject to additional variable charges for common area maintenance and other variable costs, and do not include an option to extend the lease term. As of December 31, 2023, total right-of-use assets and operating lease liabilities were approximately $ 557 thousand and $ 721 thousand, respectively. As of December 31, 2023 , the Company had no finance leases. Information related to the Company’s right-of-use assets and related lease liabilities were as follows (in thousands, except years and percentages): Year Ended December 31, 2023 2022 Operating lease costs $ 278 $ 278 Short-term lease costs 5 7 Variable lease costs 159 167 Total lease costs $ 442 $ 452 Cash paid for amounts included in measurement of lease liabilities $ 338 $ 317 Weighted-average remaining lease term (years) 2.44 3.43 Weighted-average discount rate 13.20 % 13.38 % Maturities of lease liabilities as of December 31, 2023 were as follows (in thousands): Years ending December 31, 2024 $ 349 2025 360 2026 119 Total minimum lease payments 828 Less: imputed interest ( 107 ) Total future minimum lease payments 721 Less: operating lease liabilities, current ( 276 ) Operating lease liabilities, net of current portion $ 445 Licensed Patents The Company had a minimum annual license fee of $ 75 thousand payable in two installments per year to Astellas Pharma pursuant to the amended UMass IP license agreement. The patents, along with the license agreement, expired at the end of July 2022 . These patents were fully impaired in prior years and, therefore, the expiration did not result in any impairment for the year ended December 31, 2022. The Company does not anticipate any short-term liquidity effects from this obligation as they will no longer be liable for the annual licensing fee.

Segments and Geographic Informa

Segments and Geographic Information	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Segments and Geographic Information	12. Segments and Geographic Information The Company operates the business on the basis of three reporting segments, the parent company and two business units: ISCO – therapeutic market; LCT – biomedical market; and LSC – anti-aging market. The Company does not measure the performance of its segments on any asset-based metrics. Therefore, segment information is presented only for net loss. Results of operations by market segment were as follows (in thousands): Year Ended December 31, 2023 2022 Revenues: Biomedical market $ 6,866 $ 7,131 Anti-aging market 923 1,049 Total revenues 7,789 8,180 Operating expenses: Therapeutic market 2,518 2,369 Biomedical market 4,492 4,384 Anti-aging market 1,442 1,610 Total operating expenses 8,452 8,363 Operating income (loss): Therapeutic market ( 2,518 ) ( 2,369 ) Biomedical market 2,374 2,747 Anti-aging market ( 519 ) ( 561 ) Total operating loss ( 663 ) ( 183 ) Other income (expense), net: Therapeutic market 532 ( 135 ) Biomedical market — ( 8 ) Anti-aging market — ( 5 ) Total other income (expense), net 532 ( 148 ) Net income (loss): Therapeutic market ( 1,986 ) ( 2,504 ) Biomedical market 2,374 2,739 Anti-aging market ( 519 ) ( 566 ) Total net loss $ ( 131 ) $ ( 331 ) Geographic Information The Company’s wholly owned subsidiaries are located in Maryland, California and Melbourne, Australia, and have customer and vendor relationships worldwide. The Company's long-lived assets including property, plant, and equipment, net, right-of-use assets, and intangible assets, net are domiciled in the United States. Significant revenues in the following regions are those that are attributable to the individual country within the region to which the product was shipped were as follows (in thousands): Year Ended December 31, 2023 2022 United States $ 6,548 $ 7,016 Asia 726 690 Europe 395 393 All other regions 120 81 Total $ 7,789 $ 8,180

Description of Business and S_2

Description of Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business International Stem Cell Corporation (the “Company”) was organized in Delaware in June 2005 and is publicly traded on the OTCQX under the symbol “ISCO”. The Company is primarily a research and development company, for the therapeutic market, which has focused on advancing potential clinical applications of human parthenogenetic stem cells (“hpSCs”) for the treatment of various diseases of the central nervous system and liver diseases. The Company has the following wholly owned subsidiaries: • Lifeline Cell Technology, LLC (“LCT”) – for the biomedical market, develops, manufactures and commercializes primary human cell research products including over 200 human cell culture products, including frozen human “primary” cells and the reagents (called “media”) needed to grow, maintain and differentiate the cells; • Lifeline Skin Care, Inc. (“LSC”) – for the anti-aging market, develops, manufactures and markets a category of anti-aging skin care products based on the Company’s proprietary parthenogenetic stem cell technology and small molecule technology; • Cyto Therapeutics Pty. Ltd. (“Cyto Therapeutics”) – performs research and development (“R&D”) for the therapeutic market and is currently conducting clinical trials in Australia for the use of ISC-hpNSC® in the treatment of Parkinson’s disease.
Liquidity and Going Concern	Liquidity and Going Concern The Company had an accumulated deficit of approximately $ 110.5 million as of December 31, 2023 and has historically incurred net losses and negative operating cash flows. The Company has had no revenue from its principal operations in therapeutic and clinical product development through research and development efforts. Unless the Company obtains additional financing, the Company does not have sufficient cash on hand to sustain operations for at least one year from the issuance date of these consolidated financial statements. There can be no assurance that the Company will be successful in maintaining normal operating cash flow or obtaining additional funding. These circumstances raise substantial doubt about the Company’s ability to continue as a going concern. For the foreseeable future, the Company’s ability to continue its operations is dependent upon its ability to obtain additional financing. The accompanying consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from the outcome of the uncertainty concerning the Company’s ability to continue as a going concern. The Company continues to evaluate various financing sources and options to raise working capital to help fund current research and development programs and operations. The Company will need to obtain significant additional funding from sources, including debt and/or equity financing, license arrangements, grants and/or collaborative research arrangements to sustain its operations and develop products. The timing and degree of any future capital requirements will depend on many factors, including: • the accuracy of the assumptions underlying the estimates for capital needs in 2024 and beyond; • the extent that revenues from sales of LSC and LCT products cover the related costs and provide capital; • scientific progress in research and development programs; • the magnitude and scope of the Company’s research and development programs and its ability to establish, enforce and maintain strategic arrangements for research, development, clinical testing, manufacturing and marketing; • the progress with preclinical development and clinical trials; • the extent to which third party interest in Company’s research and commercial products can be realized through effective partnerships; • the time and costs involved in obtaining regulatory approvals; • the costs involved in preparing, filing, prosecuting, maintaining, defending and enforcing patent claims; • the number and type of product candidates that the Company decides to pursue; and • the development of major public health concerns, such as the novel coronavirus outbreak, or other pandemics arising globally, and the current and future impact that such concerns may have on the Company’s operations and funding requirements. Additional debt financing may be expensive and require the Company to pledge all or a substantial portion of its assets. If additional funds are obtained through arrangements with collaborative partners, these arrangements may require the Company to relinquish rights to some of its technologies, product candidates or products that the Company would otherwise seek to develop and commercialize on its own. Furthermore, if sufficient capital is not available, the Company may be required to delay, reduce the scope of or eliminate one or more of its product initiatives. The Company’s failure to raise capital or enter into applicable arrangements when needed would have a negative impact on its financial condition.
Principles of Consolidation and Foreign Currency Transactions	Principles of Consolidation and Foreign Currency Transactions The consolidated financial statements include the accounts of International Stem Cell Corporation and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The functional currency of the Company and its subsidiaries, including its wholly owned Australian subsidiary, Cyto Therapeutics, is the U.S. dollar. Assets and liabilities that are not denominated in the functional currency are remeasured into U.S. dollars at foreign currency exchange rates in effect at the respective balance sheet dates. Revenue and expenses are translated at the average rate in effect on the date of the transaction. Net realized and unrealized gains and losses from foreign currency transactions and remeasurement are reported in general and administrative expense in the accompanying consolidated statements of operations and were not material for the periods presented.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying consolidated financial statements. Significant estimates include patent life (remaining legal life versus remaining useful life), allowance for excess and obsolete inventories, and stock option awards using the Black-Scholes option valuation model. Actual results could differ from those estimates.
Segments	Segments The Company’s chief operating decision-maker reviews financial information presented on a consolidated basis, accompanied by disaggregated information by each reportable company’s statement of operations. The Company operates the business on the basis of three reporting segments, the parent company and two business units: ISCO – therapeutic market; LCT – biomedical market; and LSC – anti-aging market.
Inventories	Inventories Inventories are accounted for using the average cost and first-in, first-out (“FIFO”) methods for LCT cell culture media and reagents, average cost and specific identification methods for LSC products, and specific identification method for other LCT products. Inventories are stated at the lower of cost or net realizable value. Laboratory supplies used in the research and development process are expensed as consumed. LCT’s inventories have a long product life cycle, do not have a shelf life when frozen, and future demand is uncertain. As such, at each reporting period, the Company estimates its reserve for allowance for excess and obsolete inventory using historical sales data and inventory turnover rates. The establishment of a reserve for excess and obsolete inventory establishes a new cost basis of inventories. If the Company is able to sell such inventories, any related reserves would be reduced in the period of sale. The value of inventories that are not expected to be sold within one year of the current reporting period is classified as non-current inventories on the accompanying consolidated balance sheets.
Accounts Receivable	Accounts Receivable Trade accounts receivable are recorded at the net invoice value and are not interest bearing. Accounts receivable primarily consist of trade accounts receivable from the sales of LCT’s products, timing of cash receipts by the Company related to LSC credit card sales to customers, as well as LSC trade receivable amounts related to spa and distributor sales. The Company measures expected credit losses for financial instruments at each reporting date based on historical experience, current conditions, and reasonable forecasts. The allowance for credit losses represents the Company's estimate of expected credit losses relating to these factors. Amounts are written off against the allowances for credit losses when the Company determines that a customer account is uncollectible. As of both December 31, 2023 and 2022 , the Company's allowance for credit losses was immaterial.
Advances	Advances In June 2008, the Company entered into an agreement with BioTime, Inc. (“BioTime”), whereby BioTime paid an advance of $ 250 thousand to LCT to produce, make, and distribute certain products. The $ 250 thousand advance will be paid down with the first $ 250 thousand of net revenues that otherwise would be allocated to LCT under the agreement. As of December 31, 2023 , no revenues were realized and attributable to BioTime under this agreement.
Property and Equipment	Property and Equipment Property and equipment are stated at cost. The provision for depreciation and amortization is computed using the straight-line method over the estimated useful lives of the assets, which are generally three to five years . Leasehold improvements are capitalized and amortized over the shorter of the remaining term of the lease or the estimated life of the assets.
Intangible Assets	Intangible Assets Intangible assets consist of acquired patent licenses and capitalized legal fees related to the acquisition, filing, maintenance, and defense of patents and trademarks. Amortization begins once the patent is issued by the appropriate authoritative bodies. In the period in which a patent application is rejected or efforts to pursue the patent are abandoned, all the related accumulated costs are expensed. Patents and other intangible assets are amortized on a straight-line basis over the shorter of the useful life of the underlying patent, which is generally 15 years, or when the intangible asset is rejected or abandoned. All amortization expense and impairment charges related to intangible assets are included in general and administrative expense in the accompanying consolidated statements of operations.
Leases	Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in right-of-use assets, operating lease obligations, current, and operating lease obligations, net of current portion, on the Company’s consolidated balance sheets. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the present value of future minimum lease payments over the lease term. As the Company’s leases do not provide an implicit rate, the Company uses a discount rate based on its estimated incremental borrowing rate to determine the right-of-use asset and operating lease liabilities to be recognized. The Company determines its incremental borrowing rate based on the terms and lease payments of its operating leases and what it would normally pay to borrow, on a collateralized basis, over similar terms for an amount equal to the lease payments. Operating lease expense is recognized on a straight-line basis over the lease term. In addition, the Company does not separate lease components from non-lease components.
Long-Lived Asset Impairment	Long-Lived Asset Impairment The Company reviews long-lived assets for impairment when events or changes in circumstances (“triggering event”) indicate that the carrying value of an asset or group of assets may not be recovered. If a triggering event is determined to have occurred, the carrying value of an asset or group of assets is compared to the future undiscounted cash flows expected to be generated by the asset or group of assets. If the carrying value exceeds the undiscounted cash flows of the asset or group of assets, then impairment exists. Fair value is generally determined using the asset’s expected future discounted cash flows or market value, if readily determinable.
Revenue Recognition	Revenue Recognition The Company's revenue consists primarily of sales of products from its two revenue-generating operating segments: the biomedical products market and anti-aging products market. The biomedical market segment markets and sells primary human cell research products with two product categories, cells and media, which are sold both domestically within the United States and internationally. The anti-aging market segment markets and sells a line of skincare products directly to customers through online orders via the ecommerce sales channel. The following table presents the Company’s revenue disaggregated by segment, product and geography (in thousands, except percentages): Biomedical market: Year Ended December 31, 2023 Total % of Total Domestic International Revenues Revenues Biomedical products Media $ 4,059 $ 683 $ 4,742 69 % Cells 1,602 522 2,124 31 % Total $ 5,661 $ 1,205 $ 6,866 100 % Year Ended December 31, 2022 Total % of Total Domestic International Revenues Revenues Biomedical products Media $ 4,572 $ 618 $ 5,190 73 % Cells 1,442 499 1,941 27 % Total $ 6,014 $ 1,117 $ 7,131 100 % Anti-aging market: Year Ended December 31, 2023 2022 Skin care products $ 923 $ 1,049 Contract terms for unit price, quantity, shipping and payment are governed by sales agreements, invoices or online order forms which the Company considers to be a customer's contract in all cases. The unit price is considered the observable stand-alone selling price for the arrangements. Any promotional or volume sales discounts are applied evenly to the units sold for purposes of calculating standalone selling price. The Company recognizes revenue when its customer obtains control of the promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. Product sales generally consist of a single performance obligation that the Company satisfies at a point in time (i.e., upon shipment of the product). For LSC products, online sales and professional sales are pre-paid through credit card charges. The Company sometimes extends 15, 30, or 60-day credit terms to select professional accounts. For biomedical products, standard payment terms for its customers are generally 30 days after the Company satisfies the performance obligation(s). For LSC, the Company honors a 30-day return policy, but historical returns have been minimal and as such, no estimated allowance for sales returns was recorded as of December 31, 2023 and 2022. The Company accounts for shipping and handling costs, recognized as cost of sales, as activities to fulfill the promise to transfer the goods to a customer. As a result, no consideration is allocated to shipping and handling costs. Rather, the Company accrues the cost of shipping and handling upon shipment of the product, and all contract revenue (i.e., the transaction price) is recognized at the same time. Variable Consideration The Company records revenue from customers in an amount that reflects the transaction price it expects to be entitled to after transferring control of those goods or services. From time to time, the Company offers sales promotions on its skincare products such as discounts and free product offers. Variable consideration is estimated at contract inception only to the extent that it is probable that a significant reversal of revenue will not occur and updated at the end of each reporting period as additional information becomes available. Contract Balances The Company records a receivable when it has an unconditional right to receive consideration after a performance obligation is satisfied. The opening and closing balances of accounts receivable, net for the year ended December 31, 2023 was $ 747 thousand and $ 574 thousand, respectively. The opening and closing balances of accounts receivable, net for the year ended December 31, 2022 was $ 844 thousand and $ 747 thousand, respectively. For the years ended December 31, 2023 and 2022 , the Company did no t incur material write-offs of its receivables. Practical Expedients The Company has elected the practical expedient to not determine whether contacts with customers contain significant financing components. The Company pays commissions on certain sales for its biomedical and anti-aging product markets once the customer payment has been received, which are accrued at the time of the sale. The Company generally expenses sales commissions when incurred because the amortization period would have been one year or less. These costs are recorded within sales and marketing expenses. In addition, the Company has elected to exclude sales taxes consideration from the determined transaction price.
Allowance for Sales Returns	Allowance for Sales Returns The Company’s anti-aging products have a 30 -day product return guarantee; however, the Company determined that there is a low probability that returns will occur based on its historical rate of returns. Historically, returns have not been significant and are recognized as a reduction to current period revenue. As of December 31, 2023 and 2022 , the Company recorded no allowance for sales returns.
Cost of Sales	Cost of Sales Cost of sales consists primarily of salaries and benefits associated with employee efforts expended directly on the production of the Company’s products, as well as related direct materials, general laboratory supplies and an allocation of overhead. Certain of the Company’s licensed technology agreements may require the Company to pay royalties based on the future sale of the Company’s products. Such royalties will be recorded as a component of cost of sales when incurred. Additionally, milestone payments or the amortization of license fees related to developed technologies used in the Company’s products will be included as a component of cost of sales to the extent that such payments become due in the future.
Advertising	Advertising Adverting costs are expensed as incurred and included as a component of selling and marketing costs on the accompanying consolidated statements of operations. For the years ended December 31, 2023 and 2022, advertising costs were approximately $ 204 thousand and $ 220 thousand, respectively.
Research and Development Costs	Research and Development Costs Research and development costs, which are expensed as incurred, primarily consist of salaries and benefits associated with research and development personnel, overhead and occupancy costs, contract services costs and amortization of license costs for technology used in research and development without alternative future uses, offset by the research and development tax credits provided by the Australian Taxation Office for qualified expenditures. Australian Research and Development Tax Credit The Company’s wholly owned subsidiary, Cyto Therapeutics, conducts various research and development activities on the Company’s product candidates in Australia. Under Australian tax law, the Australian Taxation Office provides for a refundable tax credit in the form of a cash refund equal to 43.5 % of qualified research and development expenditures, not to exceed established thresholds. The Australian Research and Development tax incentive program is a self-assessment process, and the Australian Government has the right to review the Company’s qualifying programs and related expenditures for a period of four years. If such a review were to occur and, as a result of the review and failure of a related appeal, the qualified program and related expenditures were disqualified, the respective research and development refunds could be recalled with penalties and interest. The refundable tax credit does not depend on the Company’s generation of future taxable income or ongoing tax status or position. Accordingly, the credit is not considered an element of income tax accounting under FASB Accounting Standards Codification (“ASC”) 740 – Income Taxes. The Company uses the grant accounting model by analogy to International Accounting Standards (“IAS”) 20 to account for the refundable tax credit from the Australian government. The Company recognizes the research and development tax credit as a reduction to research and development expense when there is reasonable assurance that the tax credit will be received, the relevant expenses have been incurred, and the amount can be reliably measured. During the year ended December 31, 2023 and 2022, the Company recognized a reduction in research and development expenses of $ 99 thousand and $ 80 thousand, respectively, within research and development expense on the accompanying consolidated statement of operations. As of December 31, 2023 and 2022 , the Company recognized a research and development tax credit receivable of zero and $ 80 thousand, respectively, within prepaid expenses and other current assets on the accompanying consolidated balance sheet. Employee Retention Credit Similar to the Australian Research and Development tax credit, the Company uses the grant accounting model by analogy to IAS 20 to account for the refundable Employee Retention Tax Credit (“ERC”) from the U.S. government. The Company recognized the refundable tax credit as other income when there was reasonable assurance that the tax credit will be received, the relevant expenses have been incurred, and the amount can be reliably measured. Laws and regulations concerning government programs, including the ERC, are complex and subject to varying interpretations. Claims made under these programs may also be subject to retroactive audit and review. While the Company does not believe there is a basis for estimation of an audit or recapture risk at this time, there can be no assurance that regulatory authorities will not challenge the Company’s claim to the ERC in a future period. Refer to Note 8 – Employee Retention Credit within the consolidated financial statements for further discussion.
Stock-Based Compensation	Stock-Based Compensation The cost of a stock-based award is measured at the grant date based on the estimated fair value of the award, and is recognized as expense on a straight-line basis, net of forfeitures which are recognized as incurred, over the requisite service period of the award. The fair value of stock options is estimated using the Black-Scholes option valuation model, which requires the input of subjective assumptions, including price volatility of the underlying stock, risk-free interest rate, dividend yield, and expected life of the option. The Company uses the Simplified Method to estimate the term of options granted. The fair value of restricted stock awards is based on the market value of the Company’s common stock on the date of grant.
Fair Value Measurements	Fair Value Measurements The carrying amounts of the Company’s accounts receivable, accounts payable, and accrued liabilities are considered to be representative of their respective fair values because of the short-term nature of those instruments. The carrying value of the Company's related party note payable does not approximate fair value. Refer to Note 10 – Related Party Transactions within the consolidated financial statements for further discussion.
Income Taxes	Income Taxes The Company uses the asset and liability method of accounting for income taxes. When the Company prepares its consolidated financial statements, it estimates income taxes based on the various jurisdictions and countries where it conducts business. This requires the Company to estimate current tax exposure and to assess temporary differences that result from differing treatments of certain items for tax and accounting purposes. Deferred income taxes are recognized based on the differences between the financial statement and income tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The Company then assesses the likelihood that deferred tax assets will be realized. Valuation allowances are established, when it is more likely than not the deferred tax assets will not be realized. When the Company establishes a valuation allowance or increases this allowance in an accounting period, it records a corresponding tax expense in the consolidated statements of operations. The Company includes interest and penalties related to income taxes within its provision for income taxes.
Net Loss Per Share	Net Loss Per Share Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per share attributable to common stockholders is computed by dividing the net income attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury and two-class or "if-converted" methods. The two-class method is not applicable during periods with a net loss, as the holders of the convertible preferred stock do not have an obligation to fund losses. Potentially dilutive common stock equivalents are comprised of stock options and convertible preferred stock. For the years ended December 31, 2023 and 2022, there was no difference in the number of shares used to calculate basic and diluted shares outstanding as the Company was in a net loss position. For the years ended December 31, 2023 and 2022, the following common stock options and convertible preferred stock were not included in the diluted net loss per share calculation because the effect would be anti-dilutive. Year Ended December 31, 2023 2022 Employee stock options 8,590,455 6,460,654 Redeemable convertible preferred stock 2,457,143 2,457,143 Non-redeemable convertible preferred stock 5,061,687 3,619,379 Total 16,109,285 12,537,176
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes all changes in stockholders’ deficit except those resulting from investments by owners and distributions to owners. The Company did not have any items of comprehensive loss other than net loss from operations for the years ended December 31, 2023 and 2022 .
Customer Concentrations	Customer Concentrations For the years ended December 31, 2023 and 2022 , one customer accounted for approxim ately 46 % and 45 % , respectively, of consolidated product sales, and approximately 52 % and 51 %, respectively, of biomedical product sales. As of December 31, 2023 and 2022, the same customer accounted for 47 % and 73 % , respectively, of accounts receivable, net. No other single customer accounted for more than 10% of product sales, net for the years ended December 31, 2023 and 2022 in either segment. As of December 31, 2023 , three customers individually accounted for more than 10 % of accounts receivable, net and in the aggregate, accounted for 33 % of accounts receivable, net. No other single customer accounted for more than 10% of accounts receivable, net as of December 31, 2022 .
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In August 2020, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity (“ASU 2020-06”). ASU 2020-06 intends to simplify the accounting for convertible debt instruments by reducing the number of accounting models and the number of embedded features that could be recognized separately from the host contract. Among other things, the amendment allows certain convertible debt instruments to be accounted for as a single liability measured at its amortized cost, as long as no other features require bifurcation and recognition as derivatives. Further, the amendments require use of the if-converted method in the diluted earnings per share calculation for convertible instruments. The new standard will be effective for the Company on January 1, 2024. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements and related disclosures. In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosure s (“ASU 2023-07”). ASU 2023-07 intends to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. Among other things, the amendments in ASU 2023-07 require additional information regarding significant segment expenses provided to the chief operating decision maker (“CODM”), qualitative and quantitative disclosures regarding other segment items, any additional segment profit or loss measures contemplated by the CODM when assessing segment performance, how the CODM allocates resources among segments, and the title and position of the CODM. Further, the amendments require interim segment reporting disclosures that were previously only required to be disclosed annually. ASU 2023-07 will be effective for the Company for the fiscal year ending December 31, 2024 and for interim periods beginning January 1, 2025. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosure (“ASU 2023-09”). ASU 2023-09 intends to provide improved transparency about income tax information through improvements to income tax disclosures. Among other things, the amendments in ASU 2023-09 require enhanced disclosures regarding federal, state, and foreign income taxes primarily related to the income tax rate reconciliation and income taxes paid. Further, the amendments eliminate certain disclosure requirements related to uncertain tax positions and unrecognized deferred tax liabilities. The new standard will be effective for the Company for the fiscal year ending December 31, 2025. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements and related disclosures. Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). The ASU introduced a new credit loss methodology, the Current Expected Credit Losses (“CECL”) methodology, which requires earlier recognition of credit losses, while also providing additional transparency about credit risk. The CECL methodology utilizes a lifetime “expected credit loss” measurement objective for the recognition of credit losses for loans, held-to maturity debt securities, trade receivables and other receivables measured at amortized cost at the time the financial asset is originated or acquired. Subsequent to the issuance of ASU 2016-13, the FASB issued several additional ASUs to clarify implementation guidance, provide narrow-scope improvements and provide additional disclosure guidance. The Company adopted ASC 2016-13 on January 1, 2023 . The adoption of this standard did no t have a material impact on the Company's consolidated financial statements.

Description of Business and S_3

Description of Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Revenue Disaggregated by Segment, Product and Geography	The following table presents the Company’s revenue disaggregated by segment, product and geography (in thousands, except percentages): Biomedical market: Year Ended December 31, 2023 Total % of Total Domestic International Revenues Revenues Biomedical products Media $ 4,059 $ 683 $ 4,742 69 % Cells 1,602 522 2,124 31 % Total $ 5,661 $ 1,205 $ 6,866 100 % Year Ended December 31, 2022 Total % of Total Domestic International Revenues Revenues Biomedical products Media $ 4,572 $ 618 $ 5,190 73 % Cells 1,442 499 1,941 27 % Total $ 6,014 $ 1,117 $ 7,131 100 % Anti-aging market: Year Ended December 31, 2023 2022 Skin care products $ 923 $ 1,049
Summary of Antidilutive Securities not Included in Diluted Net Loss Per Share Calculation	For the years ended December 31, 2023 and 2022, the following common stock options and convertible preferred stock were not included in the diluted net loss per share calculation because the effect would be anti-dilutive. Year Ended December 31, 2023 2022 Employee stock options 8,590,455 6,460,654 Redeemable convertible preferred stock 2,457,143 2,457,143 Non-redeemable convertible preferred stock 5,061,687 3,619,379 Total 16,109,285 12,537,176

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Summary of the Components of Inventories	The components of inventories are as follows (in thousands): December 31, 2023 2022 Raw materials $ 526 $ 615 Work in process 597 498 Finished goods 1,145 1,194 2,268 2,307 Less: allowance for inventory excess and obsolescence ( 739 ) ( 637 ) Total inventories $ 1,529 $ 1,670 Inventories $ 1,263 $ 1,384 Non-current inventories 266 286 Total inventories $ 1,529 $ 1,670
Schedule of Allowance for Inventory Excess and Obsolescence	As of December 31, 2023 and 2022, the allowance for inventory excess and obsolescence consists of the following activity (in thousands): December 31, 2023 2022 Balance, beginning of year $ 637 $ 526 Provision for inventory reserve 277 218 Write-offs ( 175 ) ( 107 ) Balance, end of year $ 739 $ 637

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment	Property and equipment consist of the following (in thousands): December 31, 2023 2022 Machinery and equipment $ 1,602 $ 1,603 Computer equipment and software 221 217 Office equipment 89 89 Leasehold improvements 617 558 Construction in progress 12 — 2,541 2,467 Less: accumulated depreciation and amortization ( 2,326 ) ( 2,219 ) Property and equipment, net $ 215 $ 248

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Intangible Assets	Intangible Assets consists of the following (in thousands): December 31, 2023 2022 Patents $ 1,290 $ 1,286 Less: accumulated amortization ( 565 ) ( 483 ) 725 803 Indefinite life logos and trademarks 75 75 Intangible assets, net $ 800 $ 878
Summary of Future Amortization Expense Related to Intangible Assets Subject to Amortization	The timing of approval of pending patent applications is uncertain and, therefore, are included in the thereafter period below until issued. Pending patents as of December 31, 2023 and 2022 was $ 61 thousand and $ 57 thousand. As of December 31, 2023, future amortization expense related to intangible assets subject to amortization is expected to be as follows (in thousands): Years ending December 31, 2024 $ 82 2025 80 2026 76 2027 73 2028 73 Thereafter 341 Total $ 725

Convertible Preferred Stock (Ta

Convertible Preferred Stock (Tables)	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Schedule of Authorized, Issued and Outstanding Shares of Non-redeemable Convertible Preferred Stock	The authorized, issued and outstanding shares of non-redeemable convertible preferred stock as of December 31, 2023 consist of the following: Shares Shares Issued and Liquidation Carrying Authorized Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 486 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-2 4,310 4,310 4,310 — Total 10,004,310 5,254,310 $ 9,796 $ 5 The authorized, issued and outstanding shares of non-redeemable convertible preferred stock as of December 31, 2022 consist of the following: Shares Shares Issued and Liquidation Carrying Authorized Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 471 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-2 4,310 4,310 4,310 — Total 10,004,310 5,254,310 $ 9,781 $ 5
Summary of Number of Shares of Common Stock into Each Share of Preferred Stock Converted	The following table summarizes the number of shares of common stock into which each share of convertible preferred stock can be converted as of December 31, 2023: Conversion Initial Current Ratio to Conversion Conversion Common Price Price Stock Series B $ 75.00 $ 0.12 8.33 Series D $ 37.50 $ 1.75 57,142.86 Series G $ 60.00 $ 9.69 0.10 Series I-2 $ 1.75 $ 1.75 571.43

Stockholders' Deficit (Tables)

Stockholders' Deficit (Tables)	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Summary of Shares of Common Stock Reserved for Future Issuance	As of December 31, 2023, the Company had shares of common stock reserved for future issuance as follows: Options outstanding 11,807,494 Common stock available for issuance under the 2010 Plan 18,025,564 Redeemable convertible preferred stock 2,457,143 Non-redeemable convertible preferred stock 5,061,687 Total 37,351,888

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Changes in Options Outstanding and Related Exercise Prices for Company's Common Stock Options Issued	The following tables summarize the changes in options outstanding and the related exercise prices for the Company’s common stock options issued: Average Weighted- Remaining Aggregate Number of Average Contractual Intrinsic Outstanding Exercise Term Value Options Price (in years) (in thousands) Outstanding at December 31, 2022 6,858,492 $ 1.02 Granted 4,950,410 $ 0.13 Expired ( 1,408 ) $ 39.98 Outstanding at December 31, 2023 11,807,494 $ 0.64 7.75 $ — Vested and expected to vest at December 31, 2023 11,213,305 $ 0.67 7.66 $ — Exercisable at December 31, 2023 6,482,569 $ 1.01 6.41 $ —
Fair Value of Stock Options Grants, Weighted Average Assumptions	The weighted-average assumptions used in the Black-Scholes option valuation model to determine the fair value of stock options grants for the years ended December 31, 2023 and 2022 were as follows: Year Ended December 31, 2023 2022 Risk-free interest rate 4.28 % 2.86 % Expected stock price volatility 91.50 % 90.29 % Expected dividend yield 0 % 0 % Expected life of options (in years) 5.69 5.71 Weighted-average grant date fair value $ 0.10 $ 0.33
Schedule of Total Stock-Based Compensation Expense	Total stock-based compensation expense for the years ended December 31, 2023 and 2022 was comprised of the following (in thousands): Year Ended December 31, 2023 2022 Cost of sales $ 3 $ 5 General and administrative 359 345 Selling and marketing 7 7 Research and development 95 42 Total $ 464 $ 399

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of Pre-tax Loss for the Jurisdictions	Pre-tax loss consists of the following jurisdictions (in thousands): December 31, December 31, 2023 2022 Domestic pre-tax book loss $ ( 76 ) $ ( 228 ) Foreign pre-tax book loss ( 55 ) ( 103 ) Consolidated pre-tax book loss $ ( 131 ) $ ( 331 )
Reconciliation of Statutory Federal Income Tax Rate and Effective Income Tax Rate	A reconciliation of the statutory federal income tax rate and the effective income tax rate for the years ended December 31, 2023 and 2022 is as follows: Year Ended December 31, 2023 2022 Statutory federal income tax rate 21.0 % 21.0 % State income taxes, net of federal taxes ( 68.0 %) ( 8.5 %) Foreign rate differentials 41.3 % 0.8 % Permanent items ( 9.2 %) ( 5.1 %) Change in valuation allowance 11,815.8 % 190.7 % Research and development tax credits limitation ( 1,241.0 %) 0.0 % Employee retention credit income 104.5 % 0.0 % Stock-based compensation ( 226.9 %) 8.0 % Adjustments to NOL ( 10,830.5 %) ( 40.6 %) ASC 740-10 adjustments 402.0 % ( 170.0 %) Other ( 9.0 %) 3.7 % Effective income tax rate 0.0 % 0.0 %
Reconciliation of the Reserve for Unrecognized Tax Benefits	A reconciliation of the reserve for unrecognized tax benefits is as follows (in thousands): Balance as of December 31, 2021 $ — Increase (decrease) related to prior year tax positions 953 Increase (decrease) related to current year tax positions — Increase (decrease) related to settlements with taxing authorities — Increase (decrease) related to lapse in statute of limitations — Balance as of December 31, 2022 953 Increase (decrease) related to prior year tax positions ( 475 ) Increase (decrease) related to current year tax positions — Increase (decrease) related to settlements with taxing authorities — Increase (decrease) related to lapse in statute of limitations — Balance as of December 31, 2023 $ 478
Summary of Significant Components of Deferred Tax Assets and Liabilities	Significant components of deferred tax assets and liabilities are as follows (in thousands): December 31, December 31, 2023 2022 Deferred tax assets: Net operating loss carryforwards $ 5,476 $ 19,266 Research and development tax credits 922 1,993 Stock-based compensation 995 1,252 IRC Section 174 costs 172 95 Intangibles 166 191 Lease liabilities 161 224 Accrued expenses 123 128 Deferred tax assets 8,015 23,149 Less: valuation allowance ( 7,858 ) ( 22,936 ) Net deferred tax assets 157 213 Deferred tax liabilities: Right-of-use assets ( 125 ) ( 171 ) Depreciation ( 32 ) ( 42 ) Total deferred tax liabilities ( 157 ) ( 213 ) Net deferred tax assets $ — $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Information Related to Right-of-use Assets and Lease Liabilities	Information related to the Company’s right-of-use assets and related lease liabilities were as follows (in thousands, except years and percentages): Year Ended December 31, 2023 2022 Operating lease costs $ 278 $ 278 Short-term lease costs 5 7 Variable lease costs 159 167 Total lease costs $ 442 $ 452 Cash paid for amounts included in measurement of lease liabilities $ 338 $ 317 Weighted-average remaining lease term (years) 2.44 3.43 Weighted-average discount rate 13.20 % 13.38 %
Schedule of Maturities of Lease Liabilities	Maturities of lease liabilities as of December 31, 2023 were as follows (in thousands): Years ending December 31, 2024 $ 349 2025 360 2026 119 Total minimum lease payments 828 Less: imputed interest ( 107 ) Total future minimum lease payments 721 Less: operating lease liabilities, current ( 276 ) Operating lease liabilities, net of current portion $ 445

Segments and Geographic Infor_2

Segments and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Results of Operations by Market Segment	Results of operations by market segment were as follows (in thousands): Year Ended December 31, 2023 2022 Revenues: Biomedical market $ 6,866 $ 7,131 Anti-aging market 923 1,049 Total revenues 7,789 8,180 Operating expenses: Therapeutic market 2,518 2,369 Biomedical market 4,492 4,384 Anti-aging market 1,442 1,610 Total operating expenses 8,452 8,363 Operating income (loss): Therapeutic market ( 2,518 ) ( 2,369 ) Biomedical market 2,374 2,747 Anti-aging market ( 519 ) ( 561 ) Total operating loss ( 663 ) ( 183 ) Other income (expense), net: Therapeutic market 532 ( 135 ) Biomedical market — ( 8 ) Anti-aging market — ( 5 ) Total other income (expense), net 532 ( 148 ) Net income (loss): Therapeutic market ( 1,986 ) ( 2,504 ) Biomedical market 2,374 2,739 Anti-aging market ( 519 ) ( 566 ) Total net loss $ ( 131 ) $ ( 331 )
Summary of Significant Revenues in Following Regions	Significant revenues in the following regions are those that are attributable to the individual country within the region to which the product was shipped were as follows (in thousands): Year Ended December 31, 2023 2022 United States $ 6,548 $ 7,016 Asia 726 690 Europe 395 393 All other regions 120 81 Total $ 7,789 $ 8,180

Description of Business and S_4

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 USD ($) ProductCategory Segment Customer Units	Dec. 31, 2022 USD ($) Customer	Dec. 31, 2021 USD ($)	Jun. 30, 2008 USD ($)
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit	$ 110,476,000	$ 110,345,000
Number of reporting segments | Segment	3
Number of business units | Units	2
Advances	$ 250,000	250,000		$ 250,000
Specified amount of revenue to be utilized for advances				$ 250,000
Revenue realized from agreement	$ 0
Intangible assets useful life	15 years
Number of revenue-generating operating segments | Segment	2
Number of product categories | ProductCategory	2
Description of payment terms	The Company's revenue consists primarily of sales of products from its two revenue-generating operating segments: the biomedical products market and anti-aging products market. The biomedical market segment markets and sells primary human cell research products with two product categories, cells and media, which are sold both domestically within the United States and internationally. The anti-aging market segment markets and sells a line of skincare products directly to customers through online orders via the ecommerce sales channel.
Accounts receivable, net	$ 574,000	747,000	$ 844,000
Write-offs of receivables	$ 0	0
Product return guarantee period	30 days
Allowance for sales returns	$ 0	0
Advertising costs	204,000	220,000
Research and development tax credit	922,000	1,993,000
Reduction in research and development expenses	$ 99,000	$ 80,000
ASU 2016-13 [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Jan. 01, 2023
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]	true
Customer Concentration Risk [Member] | Revenue, Segment Benchmark | Product Sales [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of customers more than ten percentage of revenue | Customer	1	1
Customer Concentration Risk [Member] | Major Customer [Member] | Revenue, Segment Benchmark | Product Sales [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	46%	45%
Customer Concentration Risk [Member] | Major Customer [Member] | Accounts Receivable, Net [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	47%	73%
Customer Concentration Risk [Member] | Three Customers [Member] | Accounts Receivable, Net [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of customers more than ten percentage of accounts receivable | Customer	3
Concentration risk percentage	10%
Concentration risk aggregate percentage	33%
Biomedical Market [Member] | Customer Concentration Risk [Member] | Major Customer [Member] | Revenue, Segment Benchmark
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	52%	51%
Prepaid Expenses and Other Current Assets [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Research and development tax credit	$ 0	$ 80,000
Australian Taxation Office [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Percentage of refundable tax credit on qualified research and development	43.50%
LSC [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Allowance for doubtful accounts receivable	$ 0	$ 0
Minimum [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of property and equipment	3 years
Maximum [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of property and equipment	5 years
Sales commissions amortization period	1 year

Description of Business and S_5

Description of Business and Summary of Significant Accounting Policies - Summary of Revenue Disaggregated by Segment, Product and Geography (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 7,789	$ 8,180
U.S. [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	6,548	7,016
Biomedical Market [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 6,866	$ 7,131
% of Total Revenues	100%	100%
Biomedical Market [Member] | U.S. [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 5,661	$ 6,014
Biomedical Market [Member] | International [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	1,205	1,117
Biomedical Market [Member] | Cells [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 2,124	$ 1,941
% of Total Revenues	31%	27%
Biomedical Market [Member] | Cells [Member] | U.S. [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 1,602	$ 1,442
Biomedical Market [Member] | Cells [Member] | International [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	522	499
Biomedical Market [Member] | Media [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 4,742	$ 5,190
% of Total Revenues	69%	73%
Biomedical Market [Member] | Media [Member] | U.S. [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 4,059	$ 4,572
Biomedical Market [Member] | Media [Member] | International [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	683	618
Anti-Aging Skincare Market [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 923	$ 1,049

Description of Business and S_6

Description of Business and Summary of Significant Accounting Policies - Summary of Antidilutive Securities not Included in Diluted Net Loss Per Share Calculation (Detail) - 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	16,109,285	12,537,176
Employee Stock Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	8,590,455	6,460,654
Redeemable Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	2,457,143	2,457,143
Non-redeemable Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	5,061,687	3,619,379

Inventories - Summary of the Co

Inventories - Summary of the Components of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Inventory Disclosure [Abstract]
Raw materials	$ 526	$ 615
Work in process	597	498
Finished goods	1,145	1,194
Total inventory, gross	2,268	2,307
Less: allowance for inventory excess and obsolescence	(739)	(637)
Total inventories	1,529	1,670
Inventories	1,263	1,384
Non-current inventories	$ 266	$ 286

Inventories - Schedule of Allow

Inventories - Schedule of Allowance for Inventory Excess and Obsolescence (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Inventory [Line Items]
Balance, beginning of year	$ 637
Balance, end of year	739	$ 637
Inventory Valuation and Obsolescence [Member]
Inventory [Line Items]
Balance, beginning of year	637	526
Provision for inventory reserve	277	218
Write-offs	(175)	(107)
Balance, end of year	$ 739	$ 637

Property and Equipment - Summar

Property and Equipment - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,541	$ 2,467
Less: accumulated depreciation and amortization	(2,326)	(2,219)
Property and equipment, net	215	248
Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,602	1,603
Computer Equipment and Software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	221	217
Office Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	89	89
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	617	$ 558
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 12

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 112	$ 137
Disposal of property and equipment	$ 5	$ 41

Intangible Assets - Summary of

Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Patents	$ 1,290	$ 1,286
Less: accumulated amortization	(565)	(483)
Total	725	803
Indefinite life logos and trademarks	75	75
Intangible assets, net	$ 800	$ 878

Intangible Assets - Additional

Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense	$ 82	$ 81
Pending patents	$ 61	$ 57

Intangible Assets - Summary o_2

Intangible Assets - Summary of Future Amortization Expense Related to Intangible Assets Subject to Amortization (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
2024	$ 82
2025	80
2026	76
2027	73
2028	73
Thereafter	341
Total	$ 725	$ 803

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Detail) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Class Of Stock [Line Items]
Preferred stock, shares authorized	20,000,000	20,000,000
Non-redeemable convertible preferred stock, par value	$ 0.001	$ 0.001
Series D Redeemable Convertible Preferred Stock [Member]
Class Of Stock [Line Items]
Redeemable convertible preferred stock shares authorized	50	50
Series B, Series G, Series I-1 and Series I-2 Non-redeemable Convertible Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock, shares authorized	10,004,310	10,004,310

Convertible Preferred Stock - S

Convertible Preferred Stock - Schedule of Authorized, Issued and Outstanding Shares of Non-redeemable Convertible Preferred Stock (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Class Of Stock [Line Items]
Shares Authorized	20,000,000	20,000,000
Series B [Member]
Class Of Stock [Line Items]
Shares Authorized	5,000,000	5,000,000
Shares Issued	250,000	250,000
Shares Outstanding	250,000	250,000
Liquidation Preference	$ 486	$ 471
Series G [Member]
Class Of Stock [Line Items]
Shares Authorized	5,000,000	5,000,000
Shares Issued	5,000,000	5,000,000
Shares Outstanding	5,000,000	5,000,000
Liquidation Preference	$ 5,000	$ 5,000
Carrying Value	$ 5	$ 5
Series I-2 [Member]
Class Of Stock [Line Items]
Shares Authorized	4,310	4,310
Shares Issued	4,310	4,310
Shares Outstanding	4,310	4,310
Liquidation Preference	$ 4,310	$ 4,310
Series B, Series G and Series I-2 Non-redeemable Convertible Preferred Stock [Member]
Class Of Stock [Line Items]
Shares Authorized	10,004,310	10,004,310
Shares Issued	5,254,310	5,254,310
Shares Outstanding	5,254,310	5,254,310
Liquidation Preference	$ 9,796	$ 9,781
Carrying Value	$ 5	$ 5

Convertible Preferred Stock - D

Convertible Preferred Stock - Dividends - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 USD ($)
Equity [Abstract]
Dividends declared	$ 0

Convertible Preferred Stock - L

Convertible Preferred Stock - Liquidation - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023
Series I-2 Preferred stock [Member]
Class of Stock [Line Items]
Percentage of share liquidation premium	1%

Convertible Preferred Stock -_2

Convertible Preferred Stock - Summary of Number of Shares of Common Stock into Each Share of Convertible Preferred Stock Converted (Detail)	Dec. 31, 2023 $ / shares shares
Series B [Member]
Class Of Stock [Line Items]
Initial Conversion Price	$ 75
Conversion Price	$ 0.12
Conversion Ratio to Common Stock | shares	8.33
Series D [Member]
Class Of Stock [Line Items]
Initial Conversion Price	$ 37.50
Conversion Price	$ 1.75
Conversion Ratio to Common Stock | shares	57,142.86
Series G [Member]
Class Of Stock [Line Items]
Initial Conversion Price	$ 60
Conversion Price	$ 9.69
Conversion Ratio to Common Stock | shares	0.10
Series I-2 [Member]
Class Of Stock [Line Items]
Initial Conversion Price	$ 1.75
Conversion Price	$ 1.75
Conversion Ratio to Common Stock | shares	571.43

Convertible Preferred Stock - V

Convertible Preferred Stock - Voting - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 Directors shares	Dec. 31, 2022 shares
Class Of Stock [Line Items]
Voting rights	The holders of Series B, Series D, and Series G are entitled to one vote for each share of common stock into which it would convert.
Series D Preferred Stock [Member]
Class Of Stock [Line Items]
Number of directors to be nominated and elected by preferred shareholders | Directors	2
Series D Preferred Stock [Member] | Minimum [Member]
Class Of Stock [Line Items]
Preferred stock, shares outstanding | shares	10
Series G Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock, shares outstanding | shares	5,000,000	5,000,000
Number of directors to be nominated by preferred shareholders | Directors	2
Number of independent directors out of directors to be nominated by preferred shareholders | Directors	1
Series G Preferred Stock [Member] | Minimum [Member]
Class Of Stock [Line Items]
Convertible Redeemable Preferred stock, shares outstanding | shares	1,000,000

Stockholders' Deficit - Common

Stockholders' Deficit - Common Stock - Additional Information (Detail) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Common stock, shares authorized	120,000,000	120,000,000
Common stock, par value	$ 0.001	$ 0.001

Stockholders' Deficit - Summary

Stockholders' Deficit - Summary of Shares of Common Stock Reserved for Future Issuance (Detail)	Dec. 31, 2023 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	37,351,888
Options Outstanding [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	11,807,494
Redeemable Convertible Preferred Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	2,457,143
Nonredeemable Convertible Preferred Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	5,061,687
Common Stock [Member] | 2010 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	18,025,564

Equity Incentive Plans - Additi

Equity Incentive Plans - Additional Information (Detail) - shares	1 Months Ended		12 Months Ended
	Sep. 30, 2023	Jun. 30, 2020	Dec. 31, 2023	Dec. 31, 2022	Apr. 30, 2010	Dec. 31, 2006
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, exercised			0	0
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted			0
Number of shares, outstanding			0
2006 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options			10 years
Stock options expiration date			Nov. 16, 2016
Number of options granted			0
2006 Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shaes issued						100,000
2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options			10 years
Share based payment award extended expiration, month and year		2030-03
2010 Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shaes issued	9,700,000
Number of options granted	800,000
2010 Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shaes issued	30,000,000				9,700,000
Number of options granted	10,000,000

Equity Incentive Plans - Stock

Equity Incentive Plans - Stock Options - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023
2006 Plan and 2010 Plan [Member] | Stock Options [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options	10 years

Equity Incentive Plans - Summar

Equity Incentive Plans - Summary of Changes in Options Outstanding and Related Exercise Prices for Company's Common Stock Options Issued (Detail) - 2006 Plan and 2010 Plan [Member]	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Outstanding Options, Outstanding, Beginning balance | shares	6,858,492
Number of Outstanding Options, Granted | shares	4,950,410
Number of Outstanding Options, Expired | shares	(1,408)
Number of Outstanding Options, Outstanding, Ending balance | shares	11,807,494
Number of Outstanding Options, Vested and expected to vest at December 31, 2023 | shares	11,213,305
Number of Outstanding Options, Exercisable at December 31, 2023 | shares	6,482,569
Weighted Average Exercise Price, Outstanding, Beginning balance | $ / shares	$ 1.02
Weighted Average Exercise Price, Granted | $ / shares	0.13
Weighted Average Exercise Price, Expired | $ / shares	39.98
Weighted Average Exercise Price, Outstanding, Ending balance | $ / shares	0.64
Weighted Average Exercise Price, Vested and expected to vest at December 31, 2023 | $ / shares	0.67
Weighted Average Exercise Price, Exercisable at December 31, 2023 | $ / shares	$ 1.01
Weighted Average Remaining Contractual Term (in years), Options Outstanding Ending Balance	7 years 9 months
Weighted Average Remaining Contractual Term (in years), Vested and expected to vest at December 31, 2023	7 years 7 months 28 days
Weighted Average Remaining Contractual Term (in years), Exercisable at December 31, 2023	6 years 4 months 28 days

Equity Incentive Plans - Summ_2

Equity Incentive Plans - Summary of Fair Value of Stock Options Grants, Weighted Average Assumptions (Detail) - Stock Options [Member] - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	4.28%	2.86%
Expected stock price volatility	91.50%	90.29%
Expected dividend yield	0%	0%
Expected life of options (in years)	5 years 8 months 8 days	5 years 8 months 15 days
Weighted-average grant date fair value	$ 0.1	$ 0.33

Equity Incentive Plans - Schedu

Equity Incentive Plans - Schedule of Total Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 464	$ 399
Cost of Sales [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	3	5
General and Administrative [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	359	345
Selling and Marketing [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	7	7
Research and Development [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 95	$ 42

Equity Incentive Plans - Stock-

Equity Incentive Plans - Stock-Based Compensation - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock options	$ 650
Unrecognized compensation cost related to unvested shares expected to be recognized, weighted-average period	1 year 10 months 2 days

Employee Retention Credit - Add

Employee Retention Credit - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended	10 Months Ended	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2021	Sep. 30, 2021	Mar. 31, 2021
IRS [Member]
Employees Retention Credit [Line Items]
Internal revenue service refunds		$ 238,000			$ 201,000	$ 224,000
Other income	$ 663,000
ERC [Member] | CARES Act [Member]
Employees Retention Credit [Line Items]
Percentage of qualified wages		70%	50%	100%
Maximum annual refundable tax credit			$ 10,000
Maximum refundable tax credit per employee per quarter				$ 10,000

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax [Line Items]
Net operating loss carryforwards	$ 5,476,000	$ 19,266,000
Net operating loss carryforwards, expiration date	various years beginning 2026 through 2037
Net deferred tax assets recognized	$ 0	0
Unrecognized tax benefits	478,000	953,000
Penalties or interest recognized related to unrecognized tax benefits	0	0
Federal Income Tax [Member]
Income Tax [Line Items]
Net operating loss carryforwards	$ 20,300,000	$ 73,500,000
Net operating loss carry forwards, beginning expiration year	2026
Net operating loss carryforwards, latest expiration year	2037
Federal Income Tax [Member] | Internal Revenue Code [Member]
Income Tax [Line Items]
Change in net operating loss carry forwards	$ (53,200,000)
Foreign Tax Authority [Member]
Income Tax [Line Items]
Net operating loss carryforwards	$ 1,000,000
State Income Tax [Member]
Income Tax [Line Items]
Net operating loss carryforwards, latest expiration year	2036

Income Taxes - Schedule of Pre-

Income Taxes - Schedule of Pre-tax Loss for the Jurisdictions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Domestic pre-tax book loss	$ (76)	$ (228)
Foreign pre-tax book loss	(55)	(103)
Consolidated pre-tax book loss	$ (131)	$ (331)

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Statutory Federal Income Tax Rate and Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Statutory federal income tax rate	21%	21%
State income taxes, net of federal taxes	(68.00%)	(8.50%)
Foreign rate differentials	41.30%	0.80%
Permanent items	(9.20%)	(5.10%)
Change in valuation allowance	11,815.80%	190.70%
Research and development tax credits limitation	(1241.00%)	0%
Employee retention credit income	104.50%	0%
Stock-based compensation	(226.90%)	8%
Adjustments to NOL	(10830.50%)	(40.60%)
ASC 740-10 adjustments	402%	(170.00%)
Other	(9.00%)	3.70%
Effective income tax rate	0%	0%

Income Taxes - Reconciliation_2

Income Taxes - Reconciliation of the Reserve for Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Balance at December 31, 2022	$ 953
Increase (decrease) related to prior year tax positions		$ 953
Increase (decrease) related to prior year tax positions	(475)
Balance at December 31, 2023	$ 478	$ 953

Income Taxes - Summary of Signi

Income Taxes - Summary of Significant Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 5,476	$ 19,266
Research and development tax credit	922	1,993
Stock-based compensation	995	1,252
IRC Section 174 costs	172	95
Intangibles	166	191
Lease liabilities	161	224
Accrued expenses	123	128
Deferred tax assets	8,015	23,149
Less: valuation allowance	(7,858)	(22,936)
Net deferred tax assets	157	213
Deferred tax liabilities:
Right-of-use assets	(125)	(171)
Depreciation	(32)	(42)
Total deferred tax liabilities	(157)	(213)
Net deferred tax assets	$ 0	$ 0

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)		1 Months Ended					12 Months Ended	37 Months Ended
	Dec. 15, 2021	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Mar. 31, 2022	Jan. 31, 2022	Dec. 31, 2023	Mar. 31, 2021
Related Party Transaction [Line Items]
Lease costs incurred percentage	40%
Unsecured Non-convertible Promissory Note [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount		$ 2,900,000	$ 2,900,000	$ 2,900,000	$ 2,900,000	$ 2,900,000
Maturity date						Mar. 15, 2022
Annual interest rate		4.50%	4.50%	4.50%	4.50%	4.50%
Conversion note surrendered						$ 250,000
Other Liability, Current, Related Party, Type [Extensible Enumeration]						us-gaap:RelatedPartyMember
Related party transaction, description							The outstanding principal and accrued interest on the January 2022 Note were due and payable on March 15, 2022 and may be pre-paid by the Company without penalty at any time.
Debt issuance fees		$ 0	$ 0	$ 0	$ 0
Unsecured Non-convertible Promissory Note [Member] | Chief Executive Officer and Co-Chairman [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount								$ 2,700,000
Maturity date		Sep. 15, 2023	Mar. 15, 2023	Sep. 15, 2022	Mar. 15, 2022			Jan. 15, 2022
Annual interest rate								4.50%
Extended maturity date		Sep. 15, 2024	Sep. 15, 2023	Mar. 15, 2023	Sep. 15, 2022
S Real Estate Holding LLC [Member]
Related Party Transaction [Line Items]
Lease costs incurred remaining percentage	60%

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Thousands	1 Months Ended		12 Months Ended
	Nov. 30, 2021 USD ($)	Oct. 31, 2021 USD ($)	Dec. 31, 2023 USD ($) Installment Lease	Dec. 31, 2022 USD ($)
Commitments And Contingencies [Line Items]
Number of operating leases for real estate | Lease			3
Expiry of lease	Dec. 31, 2026	Dec. 31, 2026
Base rent due under lease	$ 4	$ 11
Percentage of increase rent per annum over lease term		3.50%
Percentage of base rent abated of lease term		50%
Right-of-use asset	247	$ 232	$ 557	$ 727
Operating lease liabilities	$ 247	$ 232	721
Finance leases			0
Astellas Pharma [Member]
Commitments And Contingencies [Line Items]
Minimum license fee payable			$ 75
Number of installments per year | Installment			2
License Agreement Terminated Month Year			2022-07
San Diego | Corporate Headquarters [Member]
Commitments And Contingencies [Line Items]
Operating leases with term date			2026-12
San Diego | Supplemental Office Space [Member]
Commitments And Contingencies [Line Items]
Operating leases with term date			2026-12
Frederick, Maryland [Member]
Commitments And Contingencies [Line Items]
Operating leases with term date			2025-11

Commitments and Contingencies_2

Commitments and Contingencies - Information Related to Right-of-use Assets and Lease Liabilities (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating lease costs	$ 278	$ 278
Short-term lease costs	5	7
Variable lease costs	159	167
Total lease costs	442	452
Cash paid for amounts included in measurement of lease liabilities	$ 338	$ 317
Weighted-average remaining lease term (years)	2 years 5 months 8 days	3 years 5 months 4 days
Weighted-average discount rate	13.20%	13.38%

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Maturities of Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Nov. 30, 2021	Oct. 31, 2021
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2024	$ 349
2025	360
2026	119
Total minimum lease payments	828
Less: imputed interest	(107)
Total future minimum lease payments	721		$ 247	$ 232
Less: operating lease liabilities, current	(276)	$ (230)
Operating lease liabilities, net of current portion	$ 445	$ 720

Segments and Geographic Infor_3

Segments and Geographic Information - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 Segment Units
Segment Reporting [Abstract]
Number of reporting segments | Segment	3
Number of business units | Units	2

Segments and Geographic Infor_4

Segments and Geographic Information - Results of Operations by Market Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenues:
Total revenues	$ 7,789	$ 8,180
Operating expenses:
Total operating expenses	8,452	8,363
Operating income (loss)
Loss from operations	(663)	(183)
Other income (expense), net:
Total other income (expense), net	532	(148)
Net income (loss):
Total net loss	(131)	(331)
Anti-aging Market [Member]
Revenues:
Total revenues	923	1,049
Operating expenses:
Total operating expenses	1,442	1,610
Operating income (loss)
Loss from operations	(519)	(561)
Other income (expense), net:
Total other income (expense), net	0	(5)
Net income (loss):
Total net loss	(519)	(566)
Biomedical Market [Member]
Revenues:
Total revenues	6,866	7,131
Operating expenses:
Total operating expenses	4,492	4,384
Operating income (loss)
Loss from operations	2,374	2,747
Other income (expense), net:
Total other income (expense), net	0	(8)
Net income (loss):
Total net loss	2,374	2,739
Therapeutic Market [Member]
Operating expenses:
Total operating expenses	2,518	2,369
Operating income (loss)
Loss from operations	(2,518)	(2,369)
Other income (expense), net:
Total other income (expense), net	532	(135)
Net income (loss):
Total net loss	$ (1,986)	$ (2,504)

Segments and Geographic Infor_5

Segments and Geographic Information - Summary of Significant Revenues in Following Regions (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	$ 7,789	$ 8,180
United States [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	6,548	7,016
Asia [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	726	690
Europe [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	395	393
All Other Regions [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	$ 120	$ 81