International Stem Cell (ISCO) 10-K 30 Mar 21 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2020	Mar. 26, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Trading Symbol	ISCO
Title of 12(g) Security	Common Stock, $0.001 par value per share
Security Exchange Name	NONE
Entity Registrant Name	International Stem Cell CORP
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	5950 Priestly Drive
Entity Address, City or Town	Carlsbad
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92008
City Area Code	760
Local Phone Number	940-6383
Entity Public Float			$ 2,853,000
Entity Common Stock, Shares Outstanding		7,539,089
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
Documents Incorporated by Reference	Information from portions of the registrant’s definitive Proxy Statement for its Annual Meeting of Stockholders to be held in 2021 is incorporated by reference into Part III of this Form 10-K.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash	$ 689,000	$ 484,000
Accounts receivable, net	403,000	1,515,000
Inventory, net	917,000	1,246,000
Prepaid expenses and other current assets	174,000	207,000
Total current assets	2,183,000	3,452,000
Non-current inventory	371,000	358,000
Property and equipment, net	534,000	668,000
Intangible assets, net	1,262,000	1,335,000
Right-of-use assets	874,000	717,000
Deposits and other assets	63,000	90,000
Total assets	5,287,000	6,620,000
Current liabilities:
Accounts payable	360,000	654,000
Accrued liabilities	386,000	642,000
Operating lease liabilities, current	346,000	367,000
Advances	250,000	250,000
Paycheck Protection Program loan, current	141,000
Total current liabilities	1,483,000	1,913,000
Related party note payable	2,475,000	2,370,000
Paycheck Protection Program loan, net of current portion	517,000
Fair value of warrant liability		207,000
Operating lease liabilities, net of current portion	845,000	718,000
Total liabilities	5,320,000	5,208,000
Commitments and contingencies (Note 11)
Stockholders' Deficit:
Common stock, $0.001 par value; 120,000,000 shares authorized; 7,539,089 shares issued and outstanding at December 31, 2020 and 2019	8,000	8,000
Additional paid-in capital	104,769,000	103,490,000
Accumulated deficit	(109,115,000)	(106,391,000)
Total stockholders' deficit	(4,333,000)	(2,888,000)
Total liabilities, redeemable convertible preferred stock and stockholders' deficit	5,287,000	6,620,000
Series D Redeemable Convertible Preferred Stock [Member]
Current liabilities:
Series D redeemable convertible preferred stock, $0.001 par value; 50 shares authorized; 43 shares issued and outstanding; liquidation preference of $4,300 at December 31, 2020 and 2019	4,300,000	4,300,000
Nonredeemable Convertible Preferred Stock [Member]
Stockholders' Deficit:
Non-redeemable convertible preferred stock, $0.001 par value; 10,006,310 shares authorized; 5,255,124 shares issued and outstanding; liquidation preference of $10,565 and $10,550 at December 31, 2020 and 2019, respectively	$ 5,000	$ 5,000

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
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	7,539,089	7,539,089
Common stock, shares outstanding	7,539,089	7,539,089
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	10,006,310	10,006,310
Non-redeemable convertible preferred stock, shares issued	5,255,124	5,255,124
Non-redeemable convertible preferred stock, shares outstanding	5,255,124	5,255,124
Liquidation preference	$ 10,565	$ 10,550

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Total revenues	$ 7,128	$ 9,472
Type Of Revenue Extensible List	us-gaap:ProductMember	us-gaap:ProductMember
Operating expenses:
Cost of sales	$ 2,781	$ 3,933
Research and development	988	1,386
Selling and marketing	1,755	2,685
General and administrative	4,422	7,196
Total operating expenses	9,946	15,200
Loss from operations	(2,818)	(5,728)
Other income (expense):
Change in fair value of warrant liability	207	1,538
Interest expense	(113)	(77)
Miscellaneous income		2
Total other income, net	94	1,463
Net loss	$ (2,724)	$ (4,265)
Net loss per common share, basic and diluted	$ (0.36)	$ (0.57)
Weighted-average common shares used to compute net loss per share, basic and diluted	7,539	7,513

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, 2018	$ 2,537		$ 5	$ 7	$ 109,188	$ (106,663)
Beginning balance, shares at Dec. 31, 2018			5,255	6,934
Out of period correction	(4,300)				(8,837)	4,537
Out of period correction, Redeemable Convertible Redeemable Preferred Stock		$ 4,300
Conversion of bridge loan from a related party to common stock	1,049			$ 1	1,048
Conversion of bridge loan from a related party to common stock, shares				599
Stock-based compensation	2,087				2,087
Issuance of common stock	4				4
Issuance of common stock, shares				6
Net loss	(4,265)					(4,265)
Ending balance at Dec. 31, 2019	(2,888)		$ 5	$ 8	103,490	(106,391)
Ending balance at Dec. 31, 2019		4,300
Ending balance, shares at Dec. 31, 2019			5,255	7,539
Stock-based compensation	1,279				1,279
Net loss	(2,724)					(2,724)
Ending balance at Dec. 31, 2020	$ (4,333)		$ 5	$ 8	$ 104,769	$ (109,115)
Ending balance at Dec. 31, 2020		$ 4,300
Ending balance, shares at Dec. 31, 2020			5,255	7,539

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net loss	$ (2,724)	$ (4,265)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	253	285
Operating lease expense	265	289
Stock-based compensation	1,279	2,087
Common stock issued for services		4
Change in fair value of warrant liability	(207)	(1,538)
Interest expense on related party note payable	105	73
Impairment of intangible assets	65	1,540
Changes in operating assets and liabilities:
Accounts receivable, net	1,112	(864)
Inventory, net	316	702
Prepaid expenses and other current assets	33	336
Deposits and other assets	27	(12)
Accounts payable	(294)	196
Accrued liabilities	(256)	74
Operating lease liabilities	(315)	(304)
Net cash used in operating activities	(341)	(1,397)
Cash flows from investing activities
Purchases of property and equipment	(28)	(164)
Payments for patent licenses	(80)	(330)
Net cash used in investing activities	(108)	(494)
Cash flows from financing activities
Proceeds from Paycheck Protection Program loan	654
Proceeds from note payable from a related party		1,300
Net cash provided by financing activities	654	1,300
Net increase (decrease) in cash	205	(591)
Cash, beginning of period	484	1,075
Cash, end of period	689	484
Supplemental disclosure of cash flow information:
Cash paid for interest	5	5
Supplemental disclosure of non-cash investing and financing activities:
Right-of-use asset obtained in exchange for operating lease liability	421
Patent license costs included in accrued liabilities	$ 3
Conversion of bridge loan from a related party to common stock		$ 1,049

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
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. COVID-19 Pandemic The COVID-19 pandemic has caused business disruptions in the Company’s business globally. The Company’s consolidated financial statements reflect judgments and estimates that could change in the future as a result of the COVID-19 pandemic. For the year ended December 31, 2020, the Company experienced a year-over-year decline in product sales. In response, the Company has reduced its capital spending and, where possible, operating expenses while facilitating ongoing safe and reliable operations. As of the date of this report, the Company expects the COVID-19 pandemic will continue to adversely impact its business, financial condition, liquidity, and future results of operations. The full extent to which the COVID-19 pandemic will impact the Company remains uncertain and ultimately will be dictated by the length and severity of the pandemic, as well as the economic recovery and federal, state and local government actions taken in response. The Company is continuing to monitor the impact of COVID-19 on the Company’s operations, workforce, suppliers, customers and industry. Liquidity and Going Concern The Company had an accumulated deficit of approximately $109.1 million as of December 31, 2020 and has, on an annual basis, incurred net losses and negative operating cash flows since inception. 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 through one year from the issuance date of these 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 through the exercise of outstanding warrants, 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 2021 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 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; • the development of major public health concerns, including COVID-19 or other pandemics arising globally, and the current and future impact that such concerns may have on the Company’s operations and funding requirements; and • the extent, if any, of forgiveness of our loans under the SBA Paycheck Protection Program. As a result of the COVID-19 pandemic and actions taken to slow its spread, the global credit and financial markets have experienced extreme volatility and disruptions, including inconsistent liquidity and credit availability, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. As the pandemic continues and restrictions remain in place or new restrictions are imposed, it may make any additional debt and/or equity financing more difficult, more costly and more dilutive. In addition, 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. Reclassifications For the year ended December 31, 2019, the Company reclassified certain prior period amounts to conform to the current period presentation, as follows: • The carrying value and shares of the Company’s Series B, Series G, Series I-1 and Series I-2 non-redeemable convertible preferred stock were aggregated on the accompanying consolidated balance sheets and consolidated statements of changes in redeemable convertible preferred stock and stockholders’ deficit. Refer to Note 6 – Convertible Preferred Stock, for further discussion; • Non-cash operating lease expense was reclassified from changes in operating assets and liabilities to adjustments to reconcile net loss to net cash used in operating activities on the accompanying consolidated statements of cash flows; and • Allowance for inventory obsolescence was reclassified from adjustments to reconcile net loss to net cash used in operating expenses to inventory, net, in the changes in operating assets and liabilities on the accompanying consolidated statements of cash flows. These reclassifications had no effect on previously reported net loss, stockholders’ deficit, or cash flows for the prior period. 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), inventory carrying values, allowance for excess and obsolete inventories, allowance for sales returns and doubtful accounts, and transactions using the Black-Scholes option valuation model, for example, common stock options and warrants, as well as the Monte-Carlo simulation method for certain common stock warrants. 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. Inventory Inventory is 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. Inventory balances 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 inventory has a long product life cycle, does 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 and obsolescence using historical sales data and inventory turnover rates. The establishment of a reserve for excess and obsolete inventory establishes a new cost basis in the inventory. If the Company is able to sell such inventory, any related reserves would be reduced in the period of sale. The value of the inventory that is not expected to be sold within twelve months of the current reporting period is classified as non-current inventory 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 considers receivables past due based on the contractual payment terms. The Company reviews its exposure to accounts receivable and reserves specific amounts if collectability is no longer reasonably assured. The Company recorded an allowance for doubtful accounts of $12,000 as of December 31, 2020 and 2019. Advances In June 2008, the Company entered into an agreement with BioTime, Inc. (“BioTime”), whereby BioTime paid an advance of $250,000 to LCT to produce, make, and distribute certain products. The $250,000 advance will be paid down with the first $250,000 of net revenues that otherwise would be allocated to LCT under the agreement. As of December 31, 2020, 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. The costs of major remodeling and leasehold improvements are capitalized and amortized over the shorter of the remaining term of the lease or the estimated life of the asset. 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. 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 sold through two sales channels: ecommerce and professional. The ecommerce channel sells direct to customers through online orders, while professional sales are to spas, salons and other skincare providers. The following table presents the Company’s revenue disaggregated by segment, product and geography (in thousands): Biomedical market: Year Ended December 31, 2020 Total % of Total Domestic International Revenues Revenues Biomedical products Cells $ 838 $ 389 $ 1,227 22 % Media 3,903 447 4,350 78 % Other 17 — 17 — Total $ 4,758 $ 836 $ 5,594 100 % Year Ended December 31, 2019 Total % of Total Domestic International Revenues Revenues Biomedical products Cells $ 851 $ 395 $ 1,246 17 % Media 5,750 483 6,233 83 % Other 20 — 20 — Total $ 6,621 $ 878 $ 7,499 100 % Anti-aging market: Years Ended December 31, 2020 2019 Total % of Total Total % of Total Revenues Revenues Revenues Revenues Skin care sales channels Ecommerce $ 1,050 68 % $ 1,043 53 % Professional 484 32 % 930 47 % Total $ 1,534 100 % $ 1,973 100 % 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 delivery 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, 2020 and 2019. The Company elects to account for shipping and handling costs 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. As of December 31, 2020 and 2019, accounts receivable, net, totaled $403,000 and $1.5 million, respectively. For the years ended December 31, 2020 and 2019, the Company did not 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, 2020 and 2019, 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. 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 with alternative future uses. Research and development costs are net of research and development tax credits earned by Cyto Therapeutics, the Company’s wholly-owned subsidiary based in Australia. 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. Since the refund does not depend on an entity’s tax status or tax position, it is outside of the scope of accounting for income taxes and is treated as grant income. The Company recognized reductions to research and development costs of $157,000 and $615,000 for the years ended December 31, 2020 and 2019, respectively, attributable to the refundable tax credit. 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 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 of Financial Instruments The Company believes that the carrying value of its cash, accounts receivables, accounts payable, accrued liabilities, Paycheck Protection Program loan and related party note payable as of December 31, 2020 and 2019 approximate their fair values because of the short-term nature of those instruments. The fair value of warrants was determined at each issuance date and reporting date using the Monte-Carlo simulation model. Fair Value Measurements Fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the accounting guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1: Observable inputs such as quoted prices in active markets. Level 2: Inputs, other than the quoted prices in active markets that are observable either directly or indirectly. Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. The Company has no financial assets or liabilities, other than the warrant liability described below, measured at fair value on a recurring basis. No transfers between levels have occurred during the periods presented. The table below sets forth a summary of the Company’s liabilities which are measured at fair value on a recurring basis as of December 31, 2020 and 2019 (in thousands). Fair Value Measurements at Reporting Date Using Quoted Prices Significant in Active Other Significant Markets for Observable Unobservable Identical Assets Inputs Inputs Total (Level 1) (Level 2) (Level 3) As of December 31, 2020 Warrant liability $ — $ — $ — $ — As of December 31, 2019 Warrant liability $ 207 $ — $ — $ 207 The following table presents the rollforward activity of liabilities with inputs that are both significant to the fair value measurement and unobservable (supported by little or no market activity) (in thousands): Warrant Liability Balance at December 31, 2018 $ 1,745 Change in fair value of warrant liability (1,538 ) Balance at December 31, 2019 207 Change in fair value of warrant liability (207 ) Balance at December 31, 2020 $ - Warrant Liability The Company is required to recognize warrant agreements as a liability since they did not meet the specific conditions for equity classification and therefore need to be recognized at its fair value. The fair value of the warrant liability is calculated using the Monte-Carlo simulation model, which requires the use of certain estimates. The fair value of these warrants is re-measured at each financial reporting period with any changes in fair value being recognized as a component of other income, net, in the accompanying consolidated statements of operations. The following assumptions were used as inputs to the model: December 31, December 31, 2020 2019 Risk-free interest rate 0.08% 1.55% - 1.59% Volatility 80.0% 85.0% Term to expiration (in years) 0.21 0.29 - 1.21 Subsequent financing 0.0% 0.0% 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 loss attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury-stock and if-converted methods. Potentially dilutive common stock equivalents are comprised of stock options, common stock warrants and convertible preferred stock. For the years ended December 31, 2020 and 2019, 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, 2020 and 2019, the following common stock options, common stock warrants and convertible preferred stock were not included in the diluted net loss per share calculation because the effect would be anti-dilutive. Years Ended December 31, 2020 2019 Options outstanding 4,652,988 4,936,673 Common stock warrants outstanding 3,949,281 3,951,052 Redeemable convertible preferred stock 2,457,143 2,457,143 Non-redeemable convertible preferred stock 3,675,135 3,675,135 Total 14,734,547 15,020,003 Comprehensive Loss Comprehensive loss includes all changes in stockholders’ equity 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, 2020 and 2019. Customer Concentrations For the year ended December 31, 2020, one major customer accounted for approximately 41% of product sales. For the year ended December 31, 2019, two major customers accounted for 37% and 15% of product sales, respectively. No other single customer accounted for more than 10% of product sales for the year ended. Recently Issued Accounting Pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments— Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes In August 2020, the FASB issued 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) Recently Adopted Accounting Pronouncements In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement

Inventory

Inventory	12 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Inventory	2. Inventory The components of inventories are as follows (in thousands): December 31, December 31, 2020 2019 Raw materials $ 427 $ 688 Work in process 481 492 Finished goods 991 1,219 1,899 2,399 Less: allowance for inventory excess and obsolescence (611 ) (795 ) Total current and non-current inventory, net $ 1,288 $ 1,604 Inventory, net $ 917 $ 1,246 Non-current inventory 371 358 Total current and non-current inventory, net $ 1,288 $ 1,604 During the year ended December 31, 2020, the Company disposed of obsolete inventory in the amount of $131,000. The inventory had been fully reserved for and the write-off had no impact on the Company’s consolidated statements of operations. No obsolete inventory was disposed of during the year ended December 31, 2019.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Property and Equipment	3. Property and Equipment Property and equipment consist of the following (in thousands): December 31, December 31, 2020 2019 Machinery and equipment $ 1,661 $ 1,642 Computer equipment and software 241 236 Office equipment 230 230 Leasehold improvements 1,303 1,290 Construction in progress 3 12 3,438 3,410 Less: accumulated depreciation and amortization (2,904 ) (2,742 ) Property and equipment, net $ 534 $ 668 Depreciation and amortization expense for the years ended December 31, 2020 and 2019 was $162,000 and $156,000, respectively.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible Assets	4. Intangible Assets Intangible Assets consists of the following (in thousands): December 31, December 31, 2020 2019 Patents $ 2,286 $ 2,268 Less: accumulated amortization (1,099 ) (1,008 ) 1,187 1,260 Indefinite life logos and trademarks 75 75 Intangible assets, net $ 1,262 $ 1,335 Amortization expense for the years ended December 31, 2020 and 2019 was $91,000 and $129,000, respectively. During the years ended December 31, 2020 and 2019, the Company abandoned and fully impaired certain patents that the Company concluded it would no longer defend or incur additional costs to maintain. Impairment charges for the years ended December 31, 2020 and 2019 was $65,000 and $1.5 million, respectively. The timing of approval of pending patent applications is uncertain and, therefore, are included in the thereafter period below until issued. Pending patents at December 31, 2020 was $139,000. At December 31, 2020, future amortization expense related to intangible assets subject to amortization is expected to be as follows (in thousands): Years ending December 31, 2021 $ 93 2022 93 2023 93 2024 93 2025 93 Thereafter 722 Total $ 1,187

Paycheck Protection Program Loa

Paycheck Protection Program Loan	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Paycheck Protection Program Loan	5. Paycheck Protection Program Loan In May 2020, the Company received a loan of $654,000 from its lender under the Paycheck Protection Program (the “PPP Loan”). The Paycheck Protection Program (“PPP”), as amended, was established under the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) and is administered by the U.S. Small Business Administration (“SBA”). The PPP Loan required the Company to, in good faith, certify that the current economic uncertainty made the loan request necessary to support the ongoing operations of the Company. This certification required the Company to take into account its current business activity and its ability to access other sources of liquidity sufficient to support ongoing operations in a manner that is not significantly detrimental to the business. Based in part on the Company’s assessment of other sources of liquidity, uncertainty associated with future revenues created by the COVID-19 pandemic, and the going concern uncertainty reflected in the Company’s consolidated financial statements, the Company believes in good faith that it met the eligibility requirements for the PPP Loan. If it is later determined that the Company had violated any applicable laws or regulations or it is otherwise determined the Company was ineligible to receive the PPP Loan, it may be required to repay the PPP Loan in its entirety and/or be subject to additional penalties and potential liabilities. The PPP Loan has a two-year term and bears interest at a rate of 1% per annum. Principal and interest payments are deferred for ten months following the loan forgiveness period, which is defined as the 24-week period following the loan origination date, at which time the loan balance is payable in monthly installments unless the Company applies for, and receives, forgiveness in accordance with the CARES Act and the terms of the loan executed by the Company and its lender. As required by the CARES Act, the Company used the proceeds from the PPP Loan for payroll, healthcare benefits, rent and other qualifying expenses. The PPP provides that the use of the PPP Loan shall be limited to certain qualifying expenses and may be partially or wholly forgiven by the SBA in accordance with the requirements set forth in the CARES Act. While the Company intends to apply for forgiveness of at least a portion of the PPP Loan, there is no assurance that the Company will obtain forgiveness of the PPP Loan in whole or in part. As of December 31, 2020, $141,000 and $517,000 of outstanding principal and accrued interest of the PPP Loan was classified as current and non-current, respectively, on the accompanying consolidated balance sheets based on the contractual payment schedule of the PPP Loan. On March 18, 2021, the Company applied for and received approval for a second draw under the Paycheck Protection Program (“Second Draw”) in the amount of $474,147. See Note 13 – Subsequent Events, for further information.

Convertible Preferred Stock

Convertible Preferred Stock	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Convertible Preferred Stock	6. Convertible Preferred Stock As of December 31, 2020 and 2019, 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 a total of 10,006,310 shares of Series B, Series G, Series I-1 and Series I-2 non-redeemable convertible preferred stock. The Company’s Series B, Series G, Series I-1 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, 2020 consist of the following: Shares Shares Issued Liquidation Carrying Authorized and Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 441 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-1 2,000 814 814 — Series I-2 4,310 4,310 4,310 — Total 10,006,310 5,255,124 $ 10,565 $ 5 The authorized, issued and outstanding shares of non-redeemable convertible preferred stock as of December 31, 2019 consist of the following: Shares Shares Issued Liquidation Carrying Authorized and Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 426 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-1 2,000 814 814 — Series I-2 4,310 4,310 4,310 — Total 10,006,310 5,255,124 $ 10,550 $ 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. No dividends have been declared as of December 31, 2020. Liquidation Liquidation preference among classes of preferred shares is first with Series D with priority, followed by Series G, Series B, Series I-1 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, Series I-1 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, Series I-1 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-1 and 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 at December 31, 2020 and 2019: Initial Current Conversion Conversion Conversion Ratio to Price Price Common Stock Series B $ 75.00 $ 1.08 0.9259260 Series D $ 37.50 $ 1.75 57,142.8605 Series G $ 60.00 $ 9.70 0.103099 Series I-1 $ 1.75 $ 1.75 571.428571 Series I-2 $ 1.75 $ 1.75 571.428571 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 based on the NASDAQ listing requirements. The holders of Series I-1 and Series I-2 have 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, 2020
Stockholders Equity Note [Abstract]
Stockholders' Deficit	7. Stockholders’ Deficit Common Stock As of December 31, 2020, the Company was authorized to issue 120,000,000 shares of common stock, $0.001 par value per share. On January 21, 2019, the Company issued 599,222 shares of common stock upon conversion of a portion of the Company’s outstanding indebtedness with a principal amount of $1.0 million and accrued and unpaid interest on the principal of $49,000. In accordance with the Series G Certificate of Designation, the issuance of common stock at the conversion price of $1.75 per share triggered further adjustment in the conversion price and conversion ratio of the Series G Preferred Stock from $9.92 per share and 0.1008 shares to $9.70 per share and 0.1031 shares, respectively. The deemed dividend as a result of the down-round adjustment was immaterial. Common Stock Warrants In October 2014 and March 2016, the Company issued warrants exercisable for 62,047 and 11,159,995 shares of common stock, respectively, at an exercise price of $1.75 per share to certain placement agents and existing investors in connection with financing arrangements. As of December 31, 2019, 2,483 common stock warrants issued in October 2014 were outstanding. In April 2020, the common stock warrants issued in October 2014 expired unexercised. The common stock warrants issued in March 2016 expire on March 15, 2021. As of December 31, 2020 and 2019, 3,948,569 common stock warrants issued in March 2016 were outstanding. Common Stock Reserved for Future Issuance At December 31, 2020, the Company had shares of common stock reserved for future issuance as follows: Options outstanding 4,255,371 Common stock warrants outstanding 3,948,569 Common stock available for issuance under the 2010 Plan 5,281,104 Redeemable convertible preferred stock 2,457,143 Non-redeemable convertible preferred stock 3,675,135 Total 19,617,322

Equity Incentive Plans

Equity Incentive Plans	12 Months Ended
	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity Incentive Plans	8. 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 (the “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. 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. The following tables summarize the changes in options outstanding and the related exercise prices for the Company’s common stock options issued: Weighted- Average Remaining Number of Weighted- Contractual Aggregate Outstanding Average Term Intrinsic Value Options Exercise (in years) (in thousands) Outstanding at December 31, 2019 4,936,673 $ 3.38 8.09 $ — Granted 245,714 $ 1.08 Forfeited or canceled (923,994 ) $ 2.01 Expired (3,022 ) $ 193.50 Outstanding at December 31, 2020 4,255,371 $ 3.41 7.25 $ — Vested and expected to vest at December 31, 2020 4,219,033 $ 3.43 7.24 $ — Exercisable at December 31, 2020 3,541,030 $ 3.81 7.04 $ — Restricted Stock Awards Restricted stock awards are grants that entitle the holder to acquire shares of common stock at zero or a fixed price, which is typically nominal. The Company accounts for the restricted stock awards as issued and outstanding common stock, even though the shares covered by a restricted stock award cannot be sold, pledged, or otherwise disposed of until the award vests and any unvested shares may be reacquired by the Company for the original purchase price following the awardee’s termination of service. The fair value of restricted stock awards is based on the market value of the common stock on the date of grant. For the years ended December 31, 2020 and 2019, no restricted stock awards were awarded or vested. As of December 31, 2020, there was no unrecognized compensation costs related to unvested awards. 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, 2020 and 2019 were as follows: Years Ended December 31, 2020 2019 Risk-free interest rate 0.37% 2.44% Expected stock price volatility 88.82% 84.95% Expected dividend yield 0% 0% Expected life of options (in years) 5.36 5.71 Total stock-based compensation expense for the years ended December Years Ended December 31, 2020 2019 Cost of sales $ 87 $ 112 Research and development 135 519 Selling and marketing 78 118 General and administrative 979 1,338 Total $ 1,279 $ 2,087 Unrecognized compensation expense related to stock options as of December 31, 2020 was $604,000, which is expected to be recognized over a weighted-average period of less than one year. Unrecognized compensation expense related to stock options as of December 31, 2019 was $1.9 million, which was expected to be recognized over a weighted-average period of approximately 1.51 years.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	9. Related Party Transactions During the first quarter of 2011, the Company executed an operating lease for its corporate offices with S Real Estate Holdings LLC. S Real Estate Holdings LLC is owned by Dr. Russell Kern, the Company’s Executive Vice President and Chief Scientific Officer and a director and was previously owned by Dr. Andrey Semechkin, the Company’s Chief Executive Officer and Co-Chairman of the Board of Directors. The lease agreement was negotiated at arm’s length 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. In March 2017, the Company signed an amendment to the lease agreement to extend the term of the lease until 2020 and include annual adjustments to the monthly lease payments. In March 2020, the Company entered into an amendment to the lease agreement. The amendment extended the term of the lease for three years (until February 28, 2023) and provided for a 2% increase in monthly rent. For the years ended December 31, 2020 and 2019, the Company recorded $169,000 and $160,000, respectively, in operating lease cost that was related to the facility lease arrangement with related parties. Between March 6, 2018 and August 8, 2018, to obtain funding for working capital purposes, the Company borrowed a total of $2.0 million from Dr. Semechkin and issued an unsecured non-convertible promissory note in the principal amount of $2.0 million (the “Note”) to Dr. Semechkin (the “Noteholder”). The outstanding principal amount under the Note accrued interest at a rate of 4% per annum. The Note was due and payable November 1, 2018 and on November 12, 2018, to satisfy the indebtedness incurred on the Note, an amendment to the Note was entered into extending the due date to January 15, 2019. On January 21, 2019, the Company entered into a Note Conversion Agreement with Dr. Semechkin (the “Conversion Agreement”). The Conversion Agreement provides for the conversion of a total of $1.05 million (representing $1.0 million of principal and $49,000 of accrued interest, representing all accrued interest on the amount owed to Dr. Semechkin through January 21, 2019) under the promissory note issued to Dr. Semechkin on August 8, 2018, into a total of 599,222 shares of the Company’s common stock, representing a conversion price of $1.75 per share, which was greater than the fair value of common stock on the date of conversion at a price of $1.60 per share. Dr. Semechkin took less than fair value to avoid further dilution by triggering down-round adjustments to outstanding common stock warrants and convertible preferred stock. Due to Dr. Semechkin’s role and controlling interest in the Company, no gain was recorded by the Company upon conversion and the excess was recorded within additional paid-in capital due to the absence of retained earnings. Under the Conversion Agreement, the remaining $1.0 million owed to Dr. Semechkin under the Note has been reflected in a new unsecured, non-convertible promissory note in the principal amount of $1.0 million (the “Conversion Note”). The outstanding principal amount under the Conversion Note accrued interest at a rate of 4.5% per annum. The Conversion Note was due and payable on January 15, 2020. On April 17, 2019, to obtain additional funding for working capital purposes, the Company issued an unsecured, non-convertible promissory note (the “New Promissory Note”) in the amount of $1.8 million to Dr. Semechkin. Dr. Semechkin surrendered the Conversion Note and provided an additional $800,000 of funds to the Company. The outstanding principal amount accrued interest at a rate of 4.5% per annum and was due and payable on January 15, 2020. On December 17, 2019, to obtain additional funding for working capital purposes the Company issued an unsecured, non-convertible promissory note in the principal amount of $2.3 million (the “New Note”) to Dr. Andrey Semechkin. On December 17, 2019, the Noteholder provided an additional $500,000 of funds to the Company and surrendered the New Promissory Note, in return for the New Note. The outstanding principal amount under the New Note accrues interest at a rate of 4.5% per annum. The New Note, including outstanding amounts of principal and accrued interest, is due and payable January 15, 2021 but may be pre-paid by the Company without penalty at any time. On January 15, 2021, the Company and Dr. Semechkin agreed to extend the maturity date of the New Note to January 15, 2022. Additionally, on March 5, 2021, the Company issued Dr. Semechkin a promissory note in the amount of $2,650,000, and in exchange, Dr. Semechkin surrendered the New Note and provided an additional $350,000 of funds to the Company. See Note 13 – Subsequent Events, for further information.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes As of December 31, 2020, the Company had available net operating loss carryforwards for federal income tax reporting purposes of approximately $73.0 million and for state income tax reporting purposes of approximately $52.6 million, which may be applied against future taxable income and will expire in various years through 2037. However, any net operating loss carryforwards generated in 2018 and future years will not expire and are carried forward indefinitely. The increase in federal operating loss carryforwards for the year ended December 31, 2020 was approximately $2.0 million. The amount of and ultimate realization of the benefits from the operating loss 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 the loss carryforwards, the Company has established a valuation allowance equal to the tax effect of the loss carryforwards, research and development credits, and accruals; therefore, no net deferred tax asset has been recognized. A reconciliation of the statutory federal income tax rate and the effective income tax rate for the years ended December 31, 2020 and 2019 follows: Years Ended December 31, 2020 2019 Statutory federal income tax rate 21.0 % 21.0 % Permanent items (2.8 %) 3.0 % State income taxes, net of federal taxes (0.1 %) (0.4 %) Foreign (0.3 %) 5.0 % Change in valuation allowance (19.1 %) (13.1 %) Lease accounting (0.1 %) 1.8 % Stock options true-up (5.4 %) (18.3 %) Other 6.8 % 1.0 % Effective income tax rate 0.0 % 0.0 % The Company files income tax returns in the U.S. federal jurisdiction and various states. The Company is no longer subject to U.S. federal, state and local income tax examinations by tax authorities for years before 2016. The Company does not have any material uncertain tax positions as of December 31, 2020 and 2019. The Company does not believe it is reasonably possible that the total amount of unrecognized tax benefits as of December 31, 2020 will materially change in the next 12 months. The Company may be subject to IRC Code Section 382 and 383, which could limit the amount of the net operating loss and tax credit carryovers that can be used in future years. The Company has not 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 due to the complexity and cost associated with such study, and the fact that there may be additional such ownership changes in the future. The Company estimates that if such a change did occur, the federal and state net operating loss carryforwards and research and development credit carryforwards that can be utilized in the future would be significantly limited. 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 loss carryforwards or credit carryforwards, either due to ongoing operating losses or due to ownership change limitations. The CARES Act provides sweeping tax changes in response to the COVID-19 pandemic. Some of the more significant provisions are removal of certain limitations on utilization of net operating losses, increasing the loss carryback period for certain losses to five years, and increasing the ability to deduct interest expense, as well as amending certain provisions of the previously enacted Tax Cuts and Jobs Act. As of December 31, 2020, the Company has not recorded any material adjustments to its income tax provision related to the provisions within the CARES Act. The Company will continue to analyze the impact that the CARES Act will have, if any, on its financial position, results of operations or cash flows. Significant components of deferred tax assets and liabilities are as follows (in thousands): December 31, December 31, 2020 2019 Net operating loss carryforwards $ 19,152 $ 18,452 Stock-based compensation 1,936 1,980 Research and development tax credit 2,899 2,871 Other 397 547 Non-current deferred tax assets 24,384 23,850 Valuation allowance (24,384 ) (23,850 ) Net deferred tax assets $ — $ —

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies Leases The Company has three operating leases for real estate in California and Maryland: • Carlsbad, California – corporate offices with a term date of February 2023 and leased from a related party (see also Note 9 – Related Party Transactions); • Oceanside, California – primary research facility and laboratory space with a term date of December 2021; • Frederick, Maryland – mixed laboratory and administrative space with a term date of November 2025. 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. 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 of December 31, 2020, total right-of-use assets and operating lease liabilities were approximately $874,000 and $1.2 million, respectively. All operating lease expense is recognized on a straight-line basis over the lease term. As of December 31, 2020, 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): Years Ended December 31, 2020 2019 Operating lease costs $ 464 $ 490 Short-term lease costs 7 11 Variable lease costs 211 228 Total lease costs $ 682 $ 729 Operating cash used for operating leases 509 486 Right-of-use asset obtained in exchange for operating lease liability 421 — Weighted-average remaining lease term (years) 3.90 5.02 Weighted-average discount rate 17.05 % 17.65 % Maturities of lease liabilities as of December 31, 2020 were as follows (in thousands): Years ending December 31, 2021 $ 517 2022 394 2023 255 2024 233 2025 240 Total minimum lease payments 1,639 Less: imputed interest (448 ) Total future minimum lease payments 1,191 Less: operating lease liabilities, current (346 ) Operating lease liabilities, net of current portion $ 845 Licensed Patents The Company has a minimum annual license fee of $75,000 payable in two installments per year to Astellas Pharma pursuant to the amended UMass IP license agreement. The license agreement with Astellas Pharma may be terminated by the Company at any time with a 30-day notice.

Segments and Geographic Informa

Segments and Geographic Information	12 Months Ended
	Dec. 31, 2020
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 operating income (loss). Revenues, expenses and operating income (loss) by market segment were as follows (in thousands): Years Ended December 31, 2020 2019 Revenues: Biomedical market $ 5,594 $ 7,499 Anti-aging market 1,534 1,973 Total revenues 7,128 9,472 Operating expenses: Therapeutic market 3,410 6,345 Biomedical market 4,785 6,156 Anti-aging market 1,751 2,699 Total operating expenses 9,946 15,200 Operating income (loss) Therapeutic market (3,410 ) (6,345 ) Biomedical market 809 1,343 Anti-aging market (217 ) (726 ) Total operating loss $ (2,818 ) $ (5,728 ) Geographic Information The Company’s wholly-owned subsidiaries are located in Maryland, California and Melbourne, Australia, and have customer and vendor relationships worldwide. Significant revenues in the following regions are those that are attributable to the individual country within the region to which the product was shipped (in thousands): Years Ended December 31, 2020 2019 North America $ 6,277 $ 8,583 Asia 538 540 Europe 290 325 All other regions 23 24 Total $ 7,128 $ 9,472

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events On January 15, 2021, the Company and Dr. Semechkin, the Company’s Co-Chairman and Chief Executive Officer, agreed to extend the maturity date of the New Note to January 15, 2022. No other terms of the note were modified as a result of the extension. The New Note will continue to accrue interest at a rate of 4.5% per annum and may be pre-paid by the Company without penalty at any time. On March 5, 2021, to obtain additional funding for working capital purposes, the Company issued an unsecured, non-convertible promissory note (the “2021 Promissory Note”) in the amount of $2,650,000 to Dr. Semechkin. In exchange, Dr. Semechkin surrendered the New Note and provided an additional $350,000 of funds to the Company. The 2021 Promissory Note, including outstanding amounts of principal and accrued interest, is due and payable on January 15, 2022 but may be pre-paid by the Company without penalty at any time. On March 18, 2021, the Company received a loan of $474,147 as a Second Draw of the Paycheck Protection Program. The Second Draw is available to certain eligible borrowers and may be used to help fund payroll and benefit costs, rent, utilities, worker protection costs related to COVID-19, certain supplier costs and expenses for operations, and other related expenses. The Company’s Second Draw has a five-year term and bears interest at a rate of 1% per annum. Principal and interest payments are deferred until August 2022, at which time the loan balance is payable in monthly installments unless the Company applies for, and receives, forgiveness in accordance with the CARES Act, as amended, and the terms of the loan executed by the Company and its lender.

Description of Business and S_2

Description of Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
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.
COVID-19 Pandemic	COVID-19 Pandemic The COVID-19 pandemic has caused business disruptions in the Company’s business globally. The Company’s consolidated financial statements reflect judgments and estimates that could change in the future as a result of the COVID-19 pandemic. For the year ended December 31, 2020, the Company experienced a year-over-year decline in product sales. In response, the Company has reduced its capital spending and, where possible, operating expenses while facilitating ongoing safe and reliable operations. As of the date of this report, the Company expects the COVID-19 pandemic will continue to adversely impact its business, financial condition, liquidity, and future results of operations. The full extent to which the COVID-19 pandemic will impact the Company remains uncertain and ultimately will be dictated by the length and severity of the pandemic, as well as the economic recovery and federal, state and local government actions taken in response. The Company is continuing to monitor the impact of COVID-19 on the Company’s operations, workforce, suppliers, customers and industry.
Liquidity and Going Concern	Liquidity and Going Concern The Company had an accumulated deficit of approximately $109.1 million as of December 31, 2020 and has, on an annual basis, incurred net losses and negative operating cash flows since inception. 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 through one year from the issuance date of these 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 through the exercise of outstanding warrants, 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 2021 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 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; • the development of major public health concerns, including COVID-19 or other pandemics arising globally, and the current and future impact that such concerns may have on the Company’s operations and funding requirements; and • the extent, if any, of forgiveness of our loans under the SBA Paycheck Protection Program. As a result of the COVID-19 pandemic and actions taken to slow its spread, the global credit and financial markets have experienced extreme volatility and disruptions, including inconsistent liquidity and credit availability, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. As the pandemic continues and restrictions remain in place or new restrictions are imposed, it may make any additional debt and/or equity financing more difficult, more costly and more dilutive. In addition, 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.
Reclassifications	Reclassifications For the year ended December 31, 2019, the Company reclassified certain prior period amounts to conform to the current period presentation, as follows: • The carrying value and shares of the Company’s Series B, Series G, Series I-1 and Series I-2 non-redeemable convertible preferred stock were aggregated on the accompanying consolidated balance sheets and consolidated statements of changes in redeemable convertible preferred stock and stockholders’ deficit. Refer to Note 6 – Convertible Preferred Stock, for further discussion; • Non-cash operating lease expense was reclassified from changes in operating assets and liabilities to adjustments to reconcile net loss to net cash used in operating activities on the accompanying consolidated statements of cash flows; and • Allowance for inventory obsolescence was reclassified from adjustments to reconcile net loss to net cash used in operating expenses to inventory, net, in the changes in operating assets and liabilities on the accompanying consolidated statements of cash flows. These reclassifications had no effect on previously reported net loss, stockholders’ deficit, or cash flows for the prior period.
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), inventory carrying values, allowance for excess and obsolete inventories, allowance for sales returns and doubtful accounts, and transactions using the Black-Scholes option valuation model, for example, common stock options and warrants, as well as the Monte-Carlo simulation method for certain common stock warrants. 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.
Inventory	Inventory Inventory is 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. Inventory balances 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 inventory has a long product life cycle, does 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 and obsolescence using historical sales data and inventory turnover rates. The establishment of a reserve for excess and obsolete inventory establishes a new cost basis in the inventory. If the Company is able to sell such inventory, any related reserves would be reduced in the period of sale. The value of the inventory that is not expected to be sold within twelve months of the current reporting period is classified as non-current inventory 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 considers receivables past due based on the contractual payment terms. The Company reviews its exposure to accounts receivable and reserves specific amounts if collectability is no longer reasonably assured. The Company recorded an allowance for doubtful accounts of $12,000 as of December 31, 2020 and 2019.
Advances	Advances In June 2008, the Company entered into an agreement with BioTime, Inc. (“BioTime”), whereby BioTime paid an advance of $250,000 to LCT to produce, make, and distribute certain products. The $250,000 advance will be paid down with the first $250,000 of net revenues that otherwise would be allocated to LCT under the agreement. As of December 31, 2020, 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. The costs of major remodeling and leasehold improvements are capitalized and amortized over the shorter of the remaining term of the lease or the estimated life of the asset.
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.
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 sold through two sales channels: ecommerce and professional. The ecommerce channel sells direct to customers through online orders, while professional sales are to spas, salons and other skincare providers. The following table presents the Company’s revenue disaggregated by segment, product and geography (in thousands): Biomedical market: Year Ended December 31, 2020 Total % of Total Domestic International Revenues Revenues Biomedical products Cells $ 838 $ 389 $ 1,227 22 % Media 3,903 447 4,350 78 % Other 17 — 17 — Total $ 4,758 $ 836 $ 5,594 100 % Year Ended December 31, 2019 Total % of Total Domestic International Revenues Revenues Biomedical products Cells $ 851 $ 395 $ 1,246 17 % Media 5,750 483 6,233 83 % Other 20 — 20 — Total $ 6,621 $ 878 $ 7,499 100 % Anti-aging market: Years Ended December 31, 2020 2019 Total % of Total Total % of Total Revenues Revenues Revenues Revenues Skin care sales channels Ecommerce $ 1,050 68 % $ 1,043 53 % Professional 484 32 % 930 47 % Total $ 1,534 100 % $ 1,973 100 % 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 delivery 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, 2020 and 2019. The Company elects to account for shipping and handling costs 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. As of December 31, 2020 and 2019, accounts receivable, net, totaled $403,000 and $1.5 million, respectively. For the years ended December 31, 2020 and 2019, the Company did not 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, 2020 and 2019, 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.
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 with alternative future uses. Research and development costs are net of research and development tax credits earned by Cyto Therapeutics, the Company’s wholly-owned subsidiary based in Australia. 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. Since the refund does not depend on an entity’s tax status or tax position, it is outside of the scope of accounting for income taxes and is treated as grant income. The Company recognized reductions to research and development costs of $157,000 and $615,000 for the years ended December 31, 2020 and 2019, respectively, attributable to the refundable tax credit.
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 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 of Financial Instruments	Fair Value of Financial Instruments The Company believes that the carrying value of its cash, accounts receivables, accounts payable, accrued liabilities, Paycheck Protection Program loan and related party note payable as of December 31, 2020 and 2019 approximate their fair values because of the short-term nature of those instruments. The fair value of warrants was determined at each issuance date and reporting date using the Monte-Carlo simulation model.
Fair Value Measurements	Fair Value Measurements Fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the accounting guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1: Observable inputs such as quoted prices in active markets. Level 2: Inputs, other than the quoted prices in active markets that are observable either directly or indirectly. Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. The Company has no financial assets or liabilities, other than the warrant liability described below, measured at fair value on a recurring basis. No transfers between levels have occurred during the periods presented. The table below sets forth a summary of the Company’s liabilities which are measured at fair value on a recurring basis as of December 31, 2020 and 2019 (in thousands). Fair Value Measurements at Reporting Date Using Quoted Prices Significant in Active Other Significant Markets for Observable Unobservable Identical Assets Inputs Inputs Total (Level 1) (Level 2) (Level 3) As of December 31, 2020 Warrant liability $ — $ — $ — $ — As of December 31, 2019 Warrant liability $ 207 $ — $ — $ 207 The following table presents the rollforward activity of liabilities with inputs that are both significant to the fair value measurement and unobservable (supported by little or no market activity) (in thousands): Warrant Liability Balance at December 31, 2018 $ 1,745 Change in fair value of warrant liability (1,538 ) Balance at December 31, 2019 207 Change in fair value of warrant liability (207 ) Balance at December 31, 2020 $ -
Warrant Liability	Warrant Liability The Company is required to recognize warrant agreements as a liability since they did not meet the specific conditions for equity classification and therefore need to be recognized at its fair value. The fair value of the warrant liability is calculated using the Monte-Carlo simulation model, which requires the use of certain estimates. The fair value of these warrants is re-measured at each financial reporting period with any changes in fair value being recognized as a component of other income, net, in the accompanying consolidated statements of operations. The following assumptions were used as inputs to the model: December 31, December 31, 2020 2019 Risk-free interest rate 0.08% 1.55% - 1.59% Volatility 80.0% 85.0% Term to expiration (in years) 0.21 0.29 - 1.21 Subsequent financing 0.0% 0.0%
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 loss attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury-stock and if-converted methods. Potentially dilutive common stock equivalents are comprised of stock options, common stock warrants and convertible preferred stock. For the years ended December 31, 2020 and 2019, 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, 2020 and 2019, the following common stock options, common stock warrants and convertible preferred stock were not included in the diluted net loss per share calculation because the effect would be anti-dilutive. Years Ended December 31, 2020 2019 Options outstanding 4,652,988 4,936,673 Common stock warrants outstanding 3,949,281 3,951,052 Redeemable convertible preferred stock 2,457,143 2,457,143 Non-redeemable convertible preferred stock 3,675,135 3,675,135 Total 14,734,547 15,020,003
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes all changes in stockholders’ equity 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, 2020 and 2019.
Customer Concentrations	Customer Concentrations For the year ended December 31, 2020, one major customer accounted for approximately 41% of product sales. For the year ended December 31, 2019, two major customers accounted for 37% and 15% of product sales, respectively. No other single customer accounted for more than 10% of product sales for the year ended.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments— Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes In August 2020, the FASB issued 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) Recently Adopted Accounting Pronouncements In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement

Description of Business and S_3

Description of Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
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): Biomedical market: Year Ended December 31, 2020 Total % of Total Domestic International Revenues Revenues Biomedical products Cells $ 838 $ 389 $ 1,227 22 % Media 3,903 447 4,350 78 % Other 17 — 17 — Total $ 4,758 $ 836 $ 5,594 100 % Year Ended December 31, 2019 Total % of Total Domestic International Revenues Revenues Biomedical products Cells $ 851 $ 395 $ 1,246 17 % Media 5,750 483 6,233 83 % Other 20 — 20 — Total $ 6,621 $ 878 $ 7,499 100 % Anti-aging market: Years Ended December 31, 2020 2019 Total % of Total Total % of Total Revenues Revenues Revenues Revenues Skin care sales channels Ecommerce $ 1,050 68 % $ 1,043 53 % Professional 484 32 % 930 47 % Total $ 1,534 100 % $ 1,973 100 %
Fair Values of Liabilities on a Recurring Basis	The table below sets forth a summary of the Company’s liabilities which are measured at fair value on a recurring basis as of December 31, 2020 and 2019 (in thousands). Fair Value Measurements at Reporting Date Using Quoted Prices Significant in Active Other Significant Markets for Observable Unobservable Identical Assets Inputs Inputs Total (Level 1) (Level 2) (Level 3) As of December 31, 2020 Warrant liability $ — $ — $ — $ — As of December 31, 2019 Warrant liability $ 207 $ — $ — $ 207
Fair Value Measurement and Unobservable Rollforward Activity of Liabilities	The following table presents the rollforward activity of liabilities with inputs that are both significant to the fair value measurement and unobservable (supported by little or no market activity) (in thousands): Warrant Liability Balance at December 31, 2018 $ 1,745 Change in fair value of warrant liability (1,538 ) Balance at December 31, 2019 207 Change in fair value of warrant liability (207 ) Balance at December 31, 2020 $ -
Assumptions Used as Inputs for Warrant Liability	The following assumptions were used as inputs to the model: December 31, December 31, 2020 2019 Risk-free interest rate 0.08% 1.55% - 1.59% Volatility 80.0% 85.0% Term to expiration (in years) 0.21 0.29 - 1.21 Subsequent financing 0.0% 0.0%
Summary of Antidilutive Securities not Included in Diluted Net Loss Per Share Calculation	For the years ended December 31, 2020 and 2019, the following common stock options, common stock warrants and convertible preferred stock were not included in the diluted net loss per share calculation because the effect would be anti-dilutive. Years Ended December 31, 2020 2019 Options outstanding 4,652,988 4,936,673 Common stock warrants outstanding 3,949,281 3,951,052 Redeemable convertible preferred stock 2,457,143 2,457,143 Non-redeemable convertible preferred stock 3,675,135 3,675,135 Total 14,734,547 15,020,003

Inventory (Tables)

Inventory (Tables)	12 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Summary of the Components of Inventory	The components of inventories are as follows (in thousands): December 31, December 31, 2020 2019 Raw materials $ 427 $ 688 Work in process 481 492 Finished goods 991 1,219 1,899 2,399 Less: allowance for inventory excess and obsolescence (611 ) (795 ) Total current and non-current inventory, net $ 1,288 $ 1,604 Inventory, net $ 917 $ 1,246 Non-current inventory 371 358 Total current and non-current inventory, net $ 1,288 $ 1,604

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Summary of Property and Equipment	Property and equipment consist of the following (in thousands): December 31, December 31, 2020 2019 Machinery and equipment $ 1,661 $ 1,642 Computer equipment and software 241 236 Office equipment 230 230 Leasehold improvements 1,303 1,290 Construction in progress 3 12 3,438 3,410 Less: accumulated depreciation and amortization (2,904 ) (2,742 ) Property and equipment, net $ 534 $ 668

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Summary of Intangible Assets	Intangible Assets consists of the following (in thousands): December 31, December 31, 2020 2019 Patents $ 2,286 $ 2,268 Less: accumulated amortization (1,099 ) (1,008 ) 1,187 1,260 Indefinite life logos and trademarks 75 75 Intangible assets, net $ 1,262 $ 1,335
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 at December 31, 2020 was $139,000. At December 31, 2020, future amortization expense related to intangible assets subject to amortization is expected to be as follows (in thousands): Years ending December 31, 2021 $ 93 2022 93 2023 93 2024 93 2025 93 Thereafter 722 Total $ 1,187

Convertible Preferred Stock (Ta

Convertible Preferred Stock (Tables)	12 Months Ended
	Dec. 31, 2020
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, 2020 consist of the following: Shares Shares Issued Liquidation Carrying Authorized and Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 441 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-1 2,000 814 814 — Series I-2 4,310 4,310 4,310 — Total 10,006,310 5,255,124 $ 10,565 $ 5 The authorized, issued and outstanding shares of non-redeemable convertible preferred stock as of December 31, 2019 consist of the following: Shares Shares Issued Liquidation Carrying Authorized and Outstanding Preference Value (in thousands) Series B 5,000,000 250,000 $ 426 $ — Series G 5,000,000 5,000,000 5,000 5 Series I-1 2,000 814 814 — Series I-2 4,310 4,310 4,310 — Total 10,006,310 5,255,124 $ 10,550 $ 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 at December 31, 2020 and 2019: Initial Current Conversion Conversion Conversion Ratio to Price Price Common Stock Series B $ 75.00 $ 1.08 0.9259260 Series D $ 37.50 $ 1.75 57,142.8605 Series G $ 60.00 $ 9.70 0.103099 Series I-1 $ 1.75 $ 1.75 571.428571 Series I-2 $ 1.75 $ 1.75 571.428571

Stockholders' Deficit (Tables)

Stockholders' Deficit (Tables)	12 Months Ended
	Dec. 31, 2020
Stockholders Equity Note [Abstract]
Summary of Shares of Common Stock Reserved for Future Issuance	At December 31, 2020, the Company had shares of common stock reserved for future issuance as follows: Options outstanding 4,255,371 Common stock warrants outstanding 3,948,569 Common stock available for issuance under the 2010 Plan 5,281,104 Redeemable convertible preferred stock 2,457,143 Non-redeemable convertible preferred stock 3,675,135 Total 19,617,322

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	12 Months Ended
	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [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: Weighted- Average Remaining Number of Weighted- Contractual Aggregate Outstanding Average Term Intrinsic Value Options Exercise (in years) (in thousands) Outstanding at December 31, 2019 4,936,673 $ 3.38 8.09 $ — Granted 245,714 $ 1.08 Forfeited or canceled (923,994 ) $ 2.01 Expired (3,022 ) $ 193.50 Outstanding at December 31, 2020 4,255,371 $ 3.41 7.25 $ — Vested and expected to vest at December 31, 2020 4,219,033 $ 3.43 7.24 $ — Exercisable at December 31, 2020 3,541,030 $ 3.81 7.04 $ —
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, 2020 and 2019 were as follows: Years Ended December 31, 2020 2019 Risk-free interest rate 0.37% 2.44% Expected stock price volatility 88.82% 84.95% Expected dividend yield 0% 0% Expected life of options (in years) 5.36 5.71
Schedule of Total Stock-Based Compensation Expense	Total stock-based compensation expense for the years ended December Years Ended December 31, 2020 2019 Cost of sales $ 87 $ 112 Research and development 135 519 Selling and marketing 78 118 General and administrative 979 1,338 Total $ 1,279 $ 2,087

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
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, 2020 and 2019 follows: Years Ended December 31, 2020 2019 Statutory federal income tax rate 21.0 % 21.0 % Permanent items (2.8 %) 3.0 % State income taxes, net of federal taxes (0.1 %) (0.4 %) Foreign (0.3 %) 5.0 % Change in valuation allowance (19.1 %) (13.1 %) Lease accounting (0.1 %) 1.8 % Stock options true-up (5.4 %) (18.3 %) Other 6.8 % 1.0 % Effective income tax rate 0.0 % 0.0 %
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, 2020 2019 Net operating loss carryforwards $ 19,152 $ 18,452 Stock-based compensation 1,936 1,980 Research and development tax credit 2,899 2,871 Other 397 547 Non-current deferred tax assets 24,384 23,850 Valuation allowance (24,384 ) (23,850 ) Net deferred tax assets $ — $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2020
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): Years Ended December 31, 2020 2019 Operating lease costs $ 464 $ 490 Short-term lease costs 7 11 Variable lease costs 211 228 Total lease costs $ 682 $ 729 Operating cash used for operating leases 509 486 Right-of-use asset obtained in exchange for operating lease liability 421 — Weighted-average remaining lease term (years) 3.90 5.02 Weighted-average discount rate 17.05 % 17.65 %
Schedule of Maturities of Lease Liabilities	Maturities of lease liabilities as of December 31, 2020 were as follows (in thousands): Years ending December 31, 2021 $ 517 2022 394 2023 255 2024 233 2025 240 Total minimum lease payments 1,639 Less: imputed interest (448 ) Total future minimum lease payments 1,191 Less: operating lease liabilities, current (346 ) Operating lease liabilities, net of current portion $ 845

Segments and Geographic Infor_2

Segments and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Revenues, Expenses and Operating Income (Loss) by Market Segment	Revenues, expenses and operating income (loss) by market segment were as follows (in thousands): Years Ended December 31, 2020 2019 Revenues: Biomedical market $ 5,594 $ 7,499 Anti-aging market 1,534 1,973 Total revenues 7,128 9,472 Operating expenses: Therapeutic market 3,410 6,345 Biomedical market 4,785 6,156 Anti-aging market 1,751 2,699 Total operating expenses 9,946 15,200 Operating income (loss) Therapeutic market (3,410 ) (6,345 ) Biomedical market 809 1,343 Anti-aging market (217 ) (726 ) Total operating loss $ (2,818 ) $ (5,728 )
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 (in thousands): Years Ended December 31, 2020 2019 North America $ 6,277 $ 8,583 Asia 538 540 Europe 290 325 All other regions 23 24 Total $ 7,128 $ 9,472

Description of Business and S_4

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)SegmentUnitsProductCategorySalesChannelCustomer	Dec. 31, 2019USD ($)Customer	Jun. 30, 2008USD ($)
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit	$ 109,115,000	$ 106,391,000
Number of reporting segments | Segment	3
Number of business units | Units	2
Allowance for doubtful accounts receivable	$ 12,000	12,000
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
Number of sales channels | SalesChannel	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 sold through two sales channels: ecommerce and professional. The ecommerce channel sells direct to customers through online orders, while professional sales are to spas, salons and other skincare providers
Accounts receivable, net	$ 403,000	1,515,000
Write-offs of receivables	$ 0	0
Product return guarantee period	30 days
Allowance for sales returns	$ 0	$ 0
Financial assets	0
Financial liabilities	0
Assets transfers between Level 1 to Level 2	0
Assets transfers between Level 2 to Level 1	0
Liability transfers between Level 1 to Level 2	0
Liability transfers between Level 2 to Level 1	0
Asset transfers into Level 3	0
Asset transfers out of Level 3	0
Liability transfers into Level 3	0
Liability transfers out of Level 3	$ 0
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Jan. 1, 2020
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]	true
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201813Member
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of customers more than ten percentage of revenue | Customer		2
Customer Concentration Risk [Member] | Major customer 1 [Member] | Revenue Benchmark [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of customers more than ten percentage of revenue | Customer	1
Concentration risk percentage	41.00%	37.00%
Customer Concentration Risk [Member] | Major Customer 2 [Member] | Revenue Benchmark [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		15.00%
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%
Reductions to research and development costs	$ 157,000	$ 615,000
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, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 7,128	$ 9,472
Biomedical Market [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 5,594	$ 7,499
% of Total Revenues	100.00%	100.00%
Biomedical Market [Member] | Cells [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 1,227	$ 1,246
% of Total Revenues	22.00%	17.00%
Biomedical Market [Member] | Media [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 4,350	$ 6,233
% of Total Revenues	78.00%	83.00%
Biomedical Market [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 17	$ 20
Biomedical Market [Member] | U.S. [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	4,758	6,621
Biomedical Market [Member] | U.S. [Member] | Cells [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	838	851
Biomedical Market [Member] | U.S. [Member] | Media [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	3,903	5,750
Biomedical Market [Member] | U.S. [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	17	20
Biomedical Market [Member] | International [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	836	878
Biomedical Market [Member] | International [Member] | Cells [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	389	395
Biomedical Market [Member] | International [Member] | Media [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	447	483
Anti-Aging Skincare Market [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 1,534	$ 1,973
% of Total Revenues	100.00%	100.00%
Anti-Aging Skincare Market [Member] | Ecommerce [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 1,050	$ 1,043
% of Total Revenues	68.00%	53.00%
Anti-Aging Skincare Market [Member] | Professional [Member]
Disaggregation Of Revenue [Line Items]
Total Revenues	$ 484	$ 930
% of Total Revenues	32.00%	47.00%

Description of Business and S_6

Description of Business and Summary of Significant Accounting Policies - Fair Values of Liabilities on a Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liability	$ 0	$ 207	$ 1,745
Fair Value, Measurements, Recurring [Member] | Warrants [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liability		207
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Warrants [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Warrant liability		$ 207

Description of Business and S_7

Description of Business and Summary of Significant Accounting Policies - Fair Value Measurement and Unobservable Rollforward Activity of Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Beginning Balance	$ 207	$ 1,745
Change in fair value of warrant liability	(207)	(1,538)
Ending Balance	$ 0	$ 207

Description of Business and S_8

Description of Business and Summary of Significant Accounting Policies - Assumptions Use as Inputs for Warrant Liability (Detail)	Dec. 31, 2020	Dec. 31, 2019
Risk-Free Interest Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.08
Risk-Free Interest Rate [Member] | Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input		1.55
Risk-Free Interest Rate [Member] | Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input		1.59
Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	80	85
Term to Expiration [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Term	2 months 15 days
Term to Expiration [Member] | Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Term		3 months 14 days
Term to Expiration [Member] | Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Term		1 year 2 months 15 days
Subsequent Financing [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0	0

Description of Business and S_9

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, 2020	Dec. 31, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	14,734,547	15,020,003
Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	4,652,988	4,936,673
Common Stock Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	3,949,281	3,951,052
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	3,675,135	3,675,135

Inventory - Summary of the Comp

Inventory - Summary of the Components of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 427	$ 688
Work in process	481	492
Finished goods	991	1,219
Total current and non-current inventory, gross	1,899	2,399
Less: allowance for inventory excess and obsolescence	(611)	(795)
Total current and non-current inventory, net	1,288	1,604
Inventory, net	917	1,246
Non-current inventory	$ 371	$ 358

Inventory - Additional Informat

Inventory - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Disposed of obsolete inventory	$ 131,000	$ 0

Property and Equipment - Summar

Property and Equipment - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,438	$ 3,410
Less: accumulated depreciation and amortization	(2,904)	(2,742)
Property and equipment, net	534	668
Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,661	1,642
Computer Equipment and Software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	241	236
Office Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	230	230
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,303	1,290
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3	$ 12

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Abstract]
Depreciation and amortization expense	$ 162	$ 156

Intangible Assets - Summary of

Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Patents	$ 2,286	$ 2,268
Less: accumulated amortization	(1,099)	(1,008)
Total	1,187	1,260
Indefinite life logos and trademarks	75	75
Intangible assets, net	$ 1,262	$ 1,335

Intangible Assets - Additional

Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense	$ 91,000	$ 129,000
Impairment charges	65,000	$ 1.5
Pending patents	$ 139,000

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, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
2021	$ 93
2022	93
2023	93
2024	93
2025	93
Thereafter	722
Total	$ 1,187	$ 1,260

Paycheck Protection Program L_2

Paycheck Protection Program Loan - Additional Information (Detail) - USD ($)	Mar. 18, 2021	May 31, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Proceeds from Paycheck Protection Program loan as government aid		$ 654,000
Paycheck Protection Program loan maturity period		2 years
Paycheck Protection Program loan interest rate		1.00%
Paycheck Protection Program loan deferred payment period		10 months
Paycheck Protection Program loan forgiveness period		168 days
Paycheck Protection Program loan, current			$ 141,000
Paycheck Protection Program loan, non-current			$ 517,000
Subsequent Event [Member]
Debt Instrument [Line Items]
Proceeds from Paycheck Protection Program loan as government aid	$ 474,147
Paycheck Protection Program loan maturity period	5 years
Paycheck Protection Program loan interest rate	1.00%

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Detail) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
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	10,006,310	10,006,310

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, 2020	Dec. 31, 2019
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	$ 441	$ 426
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-1 [Member]
Class Of Stock [Line Items]
Shares Authorized	2,000	2,000
Shares Issued	814	814
Shares Outstanding	814	814
Liquidation Preference	$ 814	$ 814
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, Series I-1 and Series I-2 Non-redeemable Convertible Preferred Stock [Member]
Class Of Stock [Line Items]
Shares Authorized	10,006,310	10,006,310
Shares Issued	5,255,124	5,255,124
Shares Outstanding	5,255,124	5,255,124
Liquidation Preference	$ 10,565	$ 10,550
Carrying Value	$ 5	$ 5

Convertible Preferred Stock - D

Convertible Preferred Stock - Description of Convertible Preferred Stock - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)Directorsshares	Dec. 31, 2019shares
Class Of Stock [Line Items]
Dividends declared | $	$ 0
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. The holders of Series I-1 and Series I-2 have no voting rights
Series I-2 Preferred stock [Member]
Class Of Stock [Line Items]
Percentage of share liquidation premium	1.00%
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

Convertible Preferred Stock -_2

Convertible Preferred Stock - Summary of Number of Shares of Common Stock into Each Share of Convertible Preferred Stock Converted (Detail) - $ / shares	Jan. 21, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Series B [Member]
Class Of Stock [Line Items]
Initial Conversion Price		$ 75	$ 75
Conversion Price		$ 1.08	$ 1.08
Conversion Ratio to Common Stock		0.9259260	0.9259260
Series D Preferred Stock [Member]
Class Of Stock [Line Items]
Initial Conversion Price		$ 37.50	$ 37.50
Conversion Price		$ 1.75	$ 1.75
Conversion Ratio to Common Stock		57,142.8605	57,142.8605
Series G [Member]
Class Of Stock [Line Items]
Initial Conversion Price		$ 60	$ 60
Conversion Price	$ 9.70	$ 9.70	$ 9.70	$ 9.92
Conversion Ratio to Common Stock	0.1031	0.103099	0.103099	0.1008
Series I-1 [Member]
Class Of Stock [Line Items]
Initial Conversion Price		$ 1.75	$ 1.75
Conversion Price		$ 1.75	$ 1.75
Conversion Ratio to Common Stock		571.428571	571.428571
Series I-2 [Member]
Class Of Stock [Line Items]
Initial Conversion Price		$ 1.75	$ 1.75
Conversion Price		$ 1.75	$ 1.75
Conversion Ratio to Common Stock		571.428571	571.428571

Stockholders' Deficit - Common

Stockholders' Deficit - Common Stock - Additional Information (Detail) - USD ($)	Jan. 21, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class Of Stock [Line Items]
Common stock, shares authorized		120,000,000	120,000,000
Common stock, par value		$ 0.001	$ 0.001
Non-convertible promissory note, principal amount	$ 1,000,000
Accrued and unpaid interest	$ 49,000
Convertible common stock, conversion price		1.75
Common Stock [Member]
Class Of Stock [Line Items]
Conversion of bridge loan from a related party to common stock, shares	599,222		599,000
Series G Preferred Stock [Member]
Class Of Stock [Line Items]
Convertible preferred stock, conversion price	$ 9.70	$ 9.70	$ 9.70	$ 9.92
Conversion ratio for each share	0.1031	0.103099	0.103099	0.1008

Stockholders' Deficit - Commo_2

Stockholders' Deficit - Common Stock Warrants - Additional Information (Detail) - $ / shares	1 Months Ended
	Mar. 31, 2016	Oct. 31, 2014	Dec. 31, 2020	Dec. 31, 2019
Class Of Warrant Or Right [Line Items]
Warrants issued exercisable for shares of common stock	11,159,995	62,047
Exercise price of warrants	$ 1.75	$ 1.75
October 2014 [Member]
Class Of Warrant Or Right [Line Items]
Common stock warrants issued expiration date			Apr. 30, 2020
Common stock warrants outstanding				2,483
March 2016 [Member]
Class Of Warrant Or Right [Line Items]
Common stock warrants issued expiration date			Mar. 15, 2021
Common stock warrants outstanding			3,948,569	3,948,569

Stockholders' Deficit - Summary

Stockholders' Deficit - Summary of Shares of Common Stock Reserved for Future Issuance (Detail)	Dec. 31, 2020shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	19,617,322
Options Outstanding [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	4,255,371
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	3,675,135
Common Stock Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance net	3,948,569
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	5,281,104

Equity Incentive Plans - Additi

Equity Incentive Plans - Additional Information (Detail) - shares	1 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Apr. 30, 2010	Dec. 31, 2006
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
Options granted to employees, directors and consultants		0
2006 Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options that may be granted				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] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options that may be granted			9,700,000

Equity Incentive Plans - Stock

Equity Incentive Plans - Stock Options - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020
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] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Outstanding Options, Outstanding, Beginning balance		4,936,673
Number of Outstanding Options, Granted		245,714
Number of Outstanding Options, Forfeited or canceled	(923,994)
Number of Outstanding Options, Expired	(3,022)
Number of Outstanding Options, Outstanding, Ending balance	4,255,371
Number of Outstanding Options, Vested and expected to vest at December 31, 2020	4,219,033
Number of Outstanding Options, Exercisable at December 31, 2020	3,541,030
Weighted Average Exercise, Outstanding, Beginning balance		$ 3.38
Weighted Average Exercise, Granted		$ 1.08
Weighted Average Exercise, Forfeited or canceled	$ 2.01
Weighted Average Exercise, Expired	193.50
Weighted Average Exercise, Outstanding, Ending balance	3.41
Weighted Average Exercise, Vested and expected to vest at December 31, 2020	3.43
Weighted Average Exercise, Exercisable at December 31, 2020	$ 3.81
Weighted Average Remaining Contractual Term (in years), Options Outstanding Ending Balance	7 years 3 months	8 years 1 month 2 days
Weighted Average Remaining Contractual Term (in years), Vested and expected to vest at December 31, 2020	7 years 2 months 26 days
Weighted Average Remaining Contractual Term (in years), Exercisable at December 31, 2020	7 years 14 days

Equity Incentive Plans - Restri

Equity Incentive Plans - Restricted Stock Awards - Additional Information (Detail) - Under 2006 Plan and 2010 Plan [Member] - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Granted	0	0
Number of Shares, Vested	0	0
Grant-date fair value of restricted stock awards	$ 0	$ 0
Unrecognized compensation costs	$ 0

Equity Incentive Plans - Fair V

Equity Incentive Plans - Fair Value of Stock Options Grants, Weighted Average Assumptions (Detail) - Options [Member]	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	0.37%	2.44%
Expected stock price volatility	88.82%	84.95%
Expected dividend yield	0.00%	0.00%
Expected life of options (in years)	5 years 4 months 9 days	5 years 8 months 15 days

Equity Incentive Plans - Schedu

Equity Incentive Plans - Schedule of Total Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,279	$ 2,087
Cost of Sales [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	87	112
Research and Development [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	135	519
Selling and Marketing [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	78	118
General and Administrative [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 979	$ 1,338

Equity Incentive Plans - Stock-

Equity Incentive Plans - Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock options	$ 604,000	$ 1,900,000
Unrecognized compensation cost related to unvested shares expected to be recognized, weighted-average period		1 year 6 months 3 days
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested shares expected to be recognized, weighted-average period	1 year

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	Mar. 05, 2021	Jan. 15, 2021	Jan. 15, 2021	Dec. 17, 2019	Apr. 17, 2019	Jan. 21, 2019	Aug. 08, 2018	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Operating lease cost								$ 464,000	$ 490,000
Non-convertible promissory note, principal amount						$ 1,000,000
Debt conversion, converted instrument				$ 500,000
Accrued interest on promissory note						$ 49,000
Conversion of debt									$ 1,049,000
Conversion note surrendered				500,000	$ 800,000
Common Stock [Member]
Related Party Transaction [Line Items]
Conversion of bridge loan from a related party to common stock, shares						599,222			599,000
Conversion of debt									$ 1,000
Unsecured Non-convertible Promissory Note [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount					$ 1,800,000
Maturity date					Jan. 15, 2020
Annual interest rate					4.50%
Related party transaction, description								The outstanding principal amount accrued interest at a rate of 4.5% per annum and was due and payable on January 15, 2020
Unsecured Non-convertible Promissory Note [Member] | Subsequent Event [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount	$ 2,650,000
Conversion note surrendered	350,000
Extended maturity date			Jan. 15, 2022
Unsecured Non-convertible Promissory Note [Member] | Chief Executive Officer and Co-Chairman [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount							$ 2,000,000
Maturity date							Nov. 1, 2018
Annual interest rate							4.00%
Related party transaction, description								The outstanding principal amount under the Note accrued interest at a rate of 4% per annum. The Note was due and payable November 1, 2018 and on November 12, 2018, to satisfy the indebtedness incurred on the Note, an amendment to the Note was entered into extending the due date to January 15, 2019.
Unsecured Non-convertible Promissory Note [Member] | Co Chairman And Chief Executive Officer [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount				$ 2,300,000
Maturity date				Jan. 15, 2021
Annual interest rate				4.50%
Related party transaction, description								The outstanding principal amount under the New Note accrues interest at a rate of 4.5% per annum. The New Note, including outstanding amounts of principal and accrued interest, is due and payable January 15, 2021 but may be pre-paid by the Company without penalty at any time.
Unsecured Non-convertible Promissory Note [Member] | Co Chairman And Chief Executive Officer [Member] | Subsequent Event [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount	$ 2,650,000
Maturity date	Jan. 15, 2022	Jan. 15, 2022
Annual interest rate		4.50%
Related party transaction, description	The 2021 Promissory Note, including outstanding amounts of principal and accrued interest, is due and payable on January 15, 2022 but may be pre-paid by the Company without penalty at any time	The New Note will continue to accrue interest at a rate of 4.5% per annum and may be pre-paid by the Company without penalty at any time
Conversion note surrendered	$ 350,000
S Real Estate Holding LLC [Member]
Related Party Transaction [Line Items]
Extended term of lease								3 years
Expiry of lease								Feb. 28, 2023
Percentage of increase in monthly base rent								2.00%
Operating lease cost								$ 169,000	$ 160,000
Note Conversion Agreement [Member] | Co Chairman And Chief Executive Officer [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount						$ 1,000,000
Related party transaction, description								The outstanding principal amount under the Conversion Note accrued interest at a rate of 4.5% per annum. The Conversion Note was due and payable on January 15, 2020.
Debt conversion, converted instrument						1,050,000
Accrued interest on promissory note						$ 49,000
Conversion price						$ 1.75
Fair value of common stock price per share						$ 1.60
Gain on conversion						$ 0
Note Conversion Agreement [Member] | Co Chairman And Chief Executive Officer [Member] | Common Stock [Member]
Related Party Transaction [Line Items]
Conversion of bridge loan from a related party to common stock, shares						599,222
Note Conversion Agreement [Member] | Unsecured Non-convertible Promissory Note [Member] | Co Chairman And Chief Executive Officer [Member]
Related Party Transaction [Line Items]
Non-convertible promissory note, principal amount						$ 1,000,000
Maturity date						Jan. 15, 2020
Annual interest rate						4.50%
Conversion of debt						$ 1,000,000

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax [Line Items]
Operating loss carryforwards, latest expiration year	2037
Operating loss carryforwards, expiration date	various years through 2037
Net deferred tax assets recognized	$ 0	$ 0
Loss carryback period	5 years
Federal Income Tax [Member]
Income Tax [Line Items]
Operating loss carryforwards	$ 73,000,000
Change in operating loss carry forwards	2,000,000
State Income Tax [Member]
Income Tax [Line Items]
Operating loss carryforwards	$ 52,600,000

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Statutory Federal Income Tax Rate and Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Statutory federal income tax rate	21.00%	21.00%
Permanent items	(2.80%)	3.00%
State income taxes, net of federal taxes	(0.10%)	(0.40%)
Foreign	(0.30%)	5.00%
Change in valuation allowance	(19.10%)	(13.10%)
Lease accounting	(0.10%)	1.80%
Stock options true-up	(5.40%)	(18.30%)
Other	6.80%	1.00%
Effective income tax rate	0.00%	0.00%

Income Taxes - Summary of Signi

Income Taxes - Summary of Significant Components of Deferred Tax Assets and Liabilities (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 19,152,000	$ 18,452,000
Stock-based compensation	1,936,000	1,980,000
Research and development tax credit	2,899,000	2,871,000
Other	397,000	547,000
Non-current deferred tax assets	24,384,000	23,850,000
Valuation allowance	(24,384,000)	(23,850,000)
Net deferred tax assets	$ 0	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)LeaseInstallment	Dec. 31, 2019USD ($)
Commitments And Contingencies [Line Items]
Number of operating leases for real estate | Lease	3
Right-of-use assets	$ 874,000	$ 717,000
Operating lease liabilities	1,191,000
Finance leases	0
Astellas Pharma [Member]
Commitments And Contingencies [Line Items]
Minimum license fee payable	$ 75,000
Number of installments per year | Installment	2
Notice of termination under license agreement	30 days
Carlsbad, California [Member]
Commitments And Contingencies [Line Items]
Operating leases with term date	2023-02
Oceanside, California [Member]
Commitments And Contingencies [Line Items]
Operating leases with term date	2021-12
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 ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Leases Future Minimum Payments Due [Abstract]
Operating lease costs	$ 464	$ 490
Short-term lease costs	7	11
Variable lease costs	211	228
Total lease costs	682	729
Operating cash used for operating leases	509	$ 486
Right-of-use asset obtained in exchange for operating lease liability	$ 421
Weighted-average remaining lease term (years)	3 years 10 months 24 days	5 years 7 days
Weighted-average discount rate	17.05%	17.65%

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Maturities of Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating Leases Future Minimum Payments Due [Abstract]
2021	$ 517
2022	394
2023	255
2024	233
2025	240
Total minimum lease payments	1,639
Less: imputed interest	(448)
Total future minimum lease payments	1,191
Less: operating lease liabilities, current	(346)	$ (367)
Operating lease liabilities, net of current portion	$ 845	$ 718

Segments and Geographic Infor_3

Segments and Geographic Information - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020SegmentUnits
Segment Reporting [Abstract]
Number of reporting segments | Segment	3
Number of business units | Units	2

Segments and Geographic Infor_4

Segments and Geographic Information - Revenues, Expenses and Operating Income (Loss) by Market Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenues:
Total revenues	$ 7,128	$ 9,472
Operating expenses:
Total operating expenses	9,946	15,200
Operating income (loss)
Total operating income (loss)	(2,818)	(5,728)
Anti-aging Market [Member]
Revenues:
Total revenues	1,534	1,973
Operating expenses:
Total operating expenses	1,751	2,699
Operating income (loss)
Total operating income (loss)	(217)	(726)
Biomedical Market [Member]
Revenues:
Total revenues	5,594	7,499
Operating expenses:
Total operating expenses	4,785	6,156
Operating income (loss)
Total operating income (loss)	809	1,343
Therapeutics Market [Member]
Operating expenses:
Total operating expenses	3,410	6,345
Operating income (loss)
Total operating income (loss)	$ (3,410)	$ (6,345)

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, 2020	Dec. 31, 2019
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	$ 7,128	$ 9,472
North America [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	6,277	8,583
Asia [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	538	540
Europe [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	290	325
All Other Regions [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenues	$ 23	$ 24

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($)	Mar. 18, 2021	Mar. 05, 2021	Jan. 15, 2021	Dec. 17, 2019	Apr. 17, 2019	May 31, 2020	Dec. 31, 2020	Jan. 21, 2019
Subsequent Event [Line Items]
Non-convertible promissory note, principal amount								$ 1,000,000
Conversion note surrendered				$ 500,000	$ 800,000
Proceeds from Paycheck Protection Program loan as government aid						$ 654,000
Paycheck Protection Program loan maturity period						2 years
Paycheck Protection Program loan interest rate						1.00%
Unsecured Non-convertible Promissory Note [Member]
Subsequent Event [Line Items]
Annual interest rate					4.50%
Maturity date					Jan. 15, 2020
Related party transaction, description							The outstanding principal amount accrued interest at a rate of 4.5% per annum and was due and payable on January 15, 2020
Non-convertible promissory note, principal amount					$ 1,800,000
Co Chairman And Chief Executive Officer [Member] | Unsecured Non-convertible Promissory Note [Member]
Subsequent Event [Line Items]
Annual interest rate				4.50%
Maturity date				Jan. 15, 2021
Related party transaction, description							The outstanding principal amount under the New Note accrues interest at a rate of 4.5% per annum. The New Note, including outstanding amounts of principal and accrued interest, is due and payable January 15, 2021 but may be pre-paid by the Company without penalty at any time.
Non-convertible promissory note, principal amount				$ 2,300,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Proceeds from Paycheck Protection Program loan as government aid	$ 474,147
Paycheck Protection Program loan maturity period	5 years
Paycheck Protection Program loan interest rate	1.00%
Subsequent Event [Member] | Unsecured Non-convertible Promissory Note [Member]
Subsequent Event [Line Items]
Non-convertible promissory note, principal amount		$ 2,650,000
Conversion note surrendered		$ 350,000
Subsequent Event [Member] | Co Chairman And Chief Executive Officer [Member] | Unsecured Non-convertible Promissory Note [Member]
Subsequent Event [Line Items]
Annual interest rate			4.50%
Maturity date		Jan. 15, 2022	Jan. 15, 2022
Related party transaction, description		The 2021 Promissory Note, including outstanding amounts of principal and accrued interest, is due and payable on January 15, 2022 but may be pre-paid by the Company without penalty at any time	The New Note will continue to accrue interest at a rate of 4.5% per annum and may be pre-paid by the Company without penalty at any time
Non-convertible promissory note, principal amount		$ 2,650,000
Conversion note surrendered		$ 350,000