Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies Basis of Presentation and Consolidation The consolidated financial statements are prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). Dollar amounts contained in these consolidated financial statements are in whole numbers, unless otherwise indicated. The accompanying consolidated financial statements prior to the closing of the Merger are representative of LBS’s operations as LBS was determined to be the accounting acquirer for financial reporting purpose (see Note 3). The consolidated financial statements subsequent to the closing of the Merger include the accounts of the Company and its wholly owned subsidiaries, Leading Biosciences, Inc. and Suzhou Neuralstem Biopharmaceutical Co., Ltd. All the entities are consolidated in the Company's consolidated financial statements and all intercompany activity and transactions, if any, have been eliminated. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates, judgments, and assumptions that impact the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the balance sheet, and the reported amounts of expenses during the reporting period. The most significant estimates in the Company’s consolidated financial statements relate to clinical trial accruals and the valuation of derivative liabilities and stock-based compensation instruments. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may materially differ from these estimates and assumptions. Segment Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, the Chief Executive Officer, in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business as one operating segment which consists of research and development activities. Cash and Cash Equivalents Cash and cash equivalents represent cash available in readily available checking and money market accounts. The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Restricted Cash As of December 31, 2021 and December 31, 2020 , the Company held restricted cash of $ 26,000 , in a separate restricted bank account as collateral for the Company’s corporate credit card program. The Company has classified these deposits as long-term restricted cash on its consolidated balance sheets. Deferred Transaction Costs Deferred transaction costs consist of the legal, accounting and other direct and incremental costs incurred by the Company related to the acquisition of assets under the Merger Agreement. These costs represent legal, accounting and other direct costs related to the acquisition of assets under the Merger Agreement. As of December 31, 2020 , deferred transaction costs related to the Merger were $ 1.8 million. For the year ended December 31, 2021 , total transaction costs related to the Merger of $ 4.7 million were included in the total purchase price (see Note 3 for additional disclosure). Concentration of Credit Risk Financial instruments, which potentially subject the Company to concentration of credit risk, consist primarily of cash and cash equivalents. The Company maintains deposits in federally insured financial institutions and in money market accounts, and at times balances may exceed federally insured limits. Management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held nor has the Company experienced any losses in these accounts. Property and Equipment, Net Property and equipment, which consist of computers, are stated at cost less accumulated depreciation. Depreciation is recognized using the straight-line method over the estimated useful lives of the assets (approximately three years). Repair and maintenance costs that do not improve service potential or extend economic life are expensed as incurred. Convertible Preferred Stock The Company’s Series C Convertible Preferred Stock ("Series C Convertible Preferred Stock") has been classified as temporary equity within the accompanying consolidated balance sheet, in accordance with authoritative guidance for the classification and measurement of potentially redeemable securities as the stock is conditionally redeemable upon certain change in control events outside of the Company’s control, including the liquidation, sale or transfer of control of the Company. Upon such change in control events the holders of the Series C Convertible Preferred Stock can cause its redemption. The Company did not adjust the carrying values of the Series C Convertible Preferred Stock to its redemption value as of December 31, 2020 since a liquidation event was not probable. In connection with the Merger, the Series C Convertible Preferred Stock converted to the Company's common stock. Fair Value of Financial Instruments The Company’s financial instruments consist principally of cash and cash equivalents, restricted cash, accounts payable, accrued liabilities, debt and derivative liabilities. The carrying amounts of financial instruments such as cash equivalents, restricted cash, accounts payable, and accrued liabilities approximate their related fair values due to the short-term nature of these instruments. The carrying value of the Company’s debt approximates its fair value due to the market rate of interest, which is based on level 2 inputs. The Company’s derivative financial instruments are carried at fair value based on level 3 inputs as defined below. None of the Company’s non-financial assets or liabilities are recorded at fair value on a nonrecurring basis. The Company follows ASC 820, Fair Value Measurements and Disclosures which, among other things, defines fair value, establishes a consistent framework for measuring fair value and expands disclosure for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. Fair value is 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 determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, a three-tier fair value hierarchy has been established, which prioritizes the inputs used in measuring fair value as follows: 1) Level 1: observable inputs such as quoted prices (unadjusted) in active markets for identical assets or liabilities; 2) Level 2: inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and 3) Level 3: unobservable inputs for which there is little or no market data, which require the reporting entity to develop its own assumptions, which reflect those that a market participant would use. Further information on the fair value of financial instruments can be found at Note 5, Fair Value Measurements. Derivative Financial Instruments The Company does not use derivative instruments to hedge exposures to cash flow, market, or foreign currency risks. The Company evaluates its financial instruments, including warrants, to determine if such instruments are derivatives or contain features that qualify as embedded derivatives. The Company values its derivatives using the Black-Scholes option-pricing model or other acceptable valuation models, including Monte-Carlo simulations. Derivative instruments are valued at inception, upon events such as an exercise of the underlying financial instrument, and at subsequent reporting periods. The classification of derivative instruments, including whether such instruments should be recorded as liabilities, is re-assessed at the end of each reporting period. The Company reviews the terms of debt instruments, equity instruments, and other financing arrangements to determine whether there are embedded derivative features, including embedded conversion options that are required to be bifurcated and accounted for separately as a derivative financial instrument. Additionally, in connection with the issuance of financing instruments, the Company may issue freestanding options and warrants, including options or warrants to non-employees in exchange for consulting or other services performed. The Company accounts for its common stock warrants in accordance with Accounting Standards Codification (“ASC”) 815, Derivatives and Hedging (“ASC 815”). Based upon the provisions of ASC 815, the Company accounts for common stock warrants as liabilities if the warrant requires net cash settlement or gives the holder the option of net cash settlement, or it fails the equity classification criteria. The Company accounts for common stock warrants as equity if the contract requires physical settlement or net physical settlement or if the Company has the option of physical settlement or net physical settlement and the warrants meet the requirements to be classified as equity. Common stock warrants classified as liabilities are initially recorded at fair value on the grant date and remeasured at fair value each balance sheet date with the offset adjustments recorded in change in fair value of warrant liability within the consolidated statements of operations. Common stock warrants classified as equity are initially measured at fair value on the grant date and are not subsequently remeasured. Research and Development Costs Research and development expenses consist primarily of salaries and other personnel related expenses including stock-based compensation costs, preclinical costs, clinical trial costs, costs related to acquiring and manufacturing clinical trial materials, and contract services. All research and development costs are expensed as incurred. Clinical Trial Expenses Expenses related to clinical studies are based on estimates of the services received and efforts expended pursuant to the Company’s contract arrangements. The financial terms of these agreements are subject to negotiation, vary from contract to contract, and may result in uneven payment flows. There may be instances in which payments made to the Company’s service providers will temporarily exceed the level of services provided and result in a prepayment of the clinical expense. Payments under some of these contracts depend on factors such as the successful enrollment of patients, site initiation and the completion of clinical milestones. The Company makes estimates of its accrued expenses as of each balance sheet date in its consolidated financial statements based on facts and circumstances known at that time. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from its estimate, the Company adjusts the accrual or prepaid expense balance accordingly. Historically, the Company’s estimated accrued liabilities have materially approximated actual expense incurred. Clinical trial expenses are included in research and development expenses in the consolidated statements of operations. Patent Costs Costs related to filing and pursuing patent applications (including direct application fees, and the legal and consulting expenses related to making such applications) are expensed as incurred, as recoverability of such expenditures is uncertain. These costs are included in general and administrative expenses in the consolidated statements of operations. Debt Issuance Costs Debt issuance costs incurred to obtain debt financing are deferred and are amortized over the term of the debt using the effective interest method. Debt issuance costs are recorded as a reduction to the carrying value of the debt and are amortized to interest expense in the consolidated statements of operations. Income Taxes The Company follows the ASC 740, Income Taxes, or ASC Topic 740 (“ASC 740”), in reporting deferred income taxes. ASC 740 requires a company to recognize deferred tax assets and liabilities for expected future income tax consequences of events that have been recognized in the Company’s consolidated financial statements. Under this method, deferred tax assets and liabilities are determined based on temporary differences between financial statement carrying amounts and the tax basis of assets and liabilities using enacted tax rates in the years in which the temporary differences are expected to reverse. Valuation allowances are provided if, based on the weight of available evidence, it is more likely than not that some of or all the deferred tax assets will not be realized. The Company accounts for uncertain tax positions pursuant to ASC 740, which prescribes a recognition threshold and measurement process for financial statement recognition of uncertain tax positions taken or expected to be taken in a tax return. If the tax position meets this threshold, the benefit to be recognized is measured as the tax benefit having the highest likelihood of being realized upon ultimate settlement with the taxing authority. The Company recognizes interest accrued related to unrecognized tax benefits and penalties in the provision for income taxes. Stock-Based Compensation Stock-based compensation expense represents the cost of the estimated grant date fair value of employee and non-employee stock option grants recognized over the requisite service period of the awards, which is usually the vesting period, on a straight-line basis. The Company recognizes forfeitures as they occur as a reduction of expense. The Company estimates the fair value of employee and non-employee stock option grants using the Black-Scholes option pricing model. Net Loss Per Share Basic earnings (loss) per share is computed by dividing net income (loss) available to common stockholders by the weighted average number of shares of common stock outstanding during the period. The Company’s Series C Convertible Preferred Stock, the Senior Secured Promissory Note Warrants, the May 2021 Warrants and the July 2021 Warrants (as defined at Note 5) contain non-forfeitable rights to dividends with the common stockholders, and therefore are considered to be participating securities. The Series C Convertible Preferred Stock and the warrants do not have a contractual obligation to fund the losses of the Company; therefore, the application of the two-class method is not required when the Company is in a net loss position but is required when the Company is in a net income position. When in an net income position, diluted earnings per share is computed using the more dilutive of the two-class method or the if-converted and treasury stock methods. As the Company was in a net loss position for both periods, basic and diluted loss per share for the years ended December 31, 2021 and December 31, 2020 were calculated under the if-converted and treasury stock methods. Certain of the liability classified warrants were dilutive in the second quarter of 2021 resulting in a dilutive impact for the year ended December 31, 2021. The following table presents the calculation of weighted average shares used to calculate basic and diluted loss per share (in thousands, except share and per share amounts): Year Ended December 31, 2021 2020 Basic net loss per common share: Net loss attributable to common shares - basic $ ( 26,616 ) $ ( 10,322 ) Weighted average shares used in calculating basic loss per share 9,309,774 2,774,370 Basic net loss per common share $ ( 2.86 ) $ ( 3.72 ) Diluted net loss per common share: Net loss $ ( 26,616 ) $ ( 10,322 ) Change in fair value of warrants ( 5,119 ) — Net loss attributable to common shares - diluted $ ( 31,735 ) $ ( 10,322 ) Weighted-average shares outstanding 9,309,774 2,774,370 Effect of potentially dilutive securities 38,170 — Weighted average shares used in calculating diluted loss per share 9,347,944 2,774,370 Diluted net loss per common share $ ( 3.39 ) $ ( 3.72 ) The following potentially dilutive securities were excluded from the calculation of diluted loss per share because their effects would be anti-dilutive: Year Ended December 31, 2021 2020 Stock options 1,956,855 826,769 Warrants for common stock 7,181,741 195,712 Series C Convertible Preferred Stock — 317,420 Series A Convertible Preferred Stock 6,479 — Total 9,145,075 1,339,901 Comprehensive Income (Loss) Comprehensive income (loss) is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss was the same as its reported net loss for all periods presented. Recently Adopted Accounting Pronouncements In December 2019 , the FASB issued ASU No. 2019-12 , Income Taxes ( Topic 740 ) - Simplifying the Accounting for Income Taxes (“ASU 2019-12 " ), as part of its initiative to reduce complexity in accounting standards. The amendments in ASU 2019-12 are effective for fiscal years beginning after December 15, 2020 , including interim periods therein. Early adoption of the standard is permitted, including adoption in interim or annual periods for which financial statements have not yet been issued. As required by ASU 2019-12 , we adopted this ASU effective January 1, 2021 . The adoption of ASU No. 2019-12 did not have a material impact on the Company's financial position, results of operations or cash flows. In May 2021 , the FASB issued ASU No. 2021-04 , Earnings Per Share (Topic 260), Debt — Modifications and Extinguishments ( Subtopic 470-50 ), Compensation — Stock Compensation (Topic 718), and Derivatives and Hedging — Contracts in Entity ’ s Own Equity (Subtopic 815-40): Issuer ’ s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (“ASU 2021-04 " ). The accounting standard update is effective for fiscal years beginning after December 15, 2021. The Company early adopted this standard effective January 1, 2021 and evaluated all outstanding financial instruments that would fall under the scope of ASU 2021-04 . The adoption of this standard did not have a significant impact on the on the Company's consolidated financial statement and related disclosures. Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13 , Financial Instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). The ASU introduced a new credit loss methodology, the Current Expected Credit Losses (“CECL”) methodology, which requires earlier recognition of credit losses, while also providing additional transparency about credit risk. The CECL methodology utilizes a lifetime “expected credit loss” measurement objective for the recognition of credit losses for loans, held-to maturity debt securities, trade receivables and other receivables measured at amortized cost at the time the financial asset is originated or acquired. After the issuance of ASU 2016-13 , the FASB issued several additional ASUs to clarify implementation guidance, provide narrow-scope improvements and provide additional disclosure guidance. In November 2019, the FASB issued an amendment making this ASU effective for fiscal years beginning after December 15, 2022 for smaller reporting companies. The Company plans to adopt this standard in the first quarter of 2023 and does not expect the adoption will have a significant impact on its consolidated financial statements and related disclosures. In August 2020, 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) — Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity ("ASU 2020-06"), which, among other things, provides guidance on how to account for contracts on an entity’s own equity. This ASU simplifies the accounting for certain financial instruments with characteristics of liabilities and equity. Specifically, the ASU eliminated the need for the Company to assess whether a contract on the entity’s own equity (1) permits settlement in unregistered shares, (2) whether counterparty rights rank higher stockholder’s rights, and (3) whether collateral is required. In addition, the ASU requires incremental disclosure related to contracts on the entity’s own equity and clarifies the treatment of certain financial instruments accounted for under this ASU on earnings per share. This ASU may be applied on a full retrospective of modified retrospective basis. For smaller reporting companies, this ASU is effective for fiscal years beginning after December 15, 2023 , including interim periods within those fiscal years. Early adoption of the ASU is permitted for fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. The Company is considering early adoption of this standard in 2022 and is currently evaluating the potential impact the adoption of this standard will have on its consolidated financial statements. |