Nature of Operations. Avadel Pharmaceuticals plc (Nasdaq: AVDL) (“Avadel,” the “Company,” “we,” “our,” or “us”) is a biopharmaceutical company. The Company is registered as an Irish public limited company. The Company’s headquarters are in Dublin, Ireland with operations in Dublin, Ireland and St. Louis, Missouri, United States (“U.S”).

The Company’s lead product candidate, LUMRYZ, also known as FT218, is an investigational once-at-bedtime, extended-release formulation of sodium oxybate for the treatment of cataplexy or excessive daytime sleepiness (“EDS”) in adults with narcolepsy. On July 18, 2022, the U.S. Food and Drug Administration (“FDA”) granted tentative approval to LUMRYZ for this indication. Tentative approval indicates that LUMRYZ has met all required quality, safety, and efficacy standards necessary for approval in the U.S. On March 1, 2023, the Company submitted an amendment to the FDA requesting final approval of the LUMRYZ new drug application (“NDA”) and is currently awaiting a final approval decision from the FDA. The Company cannot legally market LUMRYZ in the U.S. until final approval is granted by the FDA.

The accompanying consolidated financial statements are prepared in accordance with accounting principles generally accepted in the U.S. (“U.S. GAAP”) applicable to a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business.

The Company has a recent history of generating losses and negative cash flows from operations, an accumulated shareholders’ deficit as of the date of these audited consolidated financial statements and approximately $73,981 of cash and cash equivalents and $22,518 of marketable securities available for use to fund its operations, debt service and capital requirements. The Company’s ability to generate revenue is expected to start following the launch of LUMRYZ, which is dependent, in part, on final approval of LUMRYZ by the FDA.

As of December 31, 2022, the Company had $17,500 aggregate principal amount of its 4.50% exchangeable senior notes due February 2023 (the “February 2023 Notes”) and $117,375 aggregate principal amount of its 4.50% exchangeable senior notes due October 2023 (the “October 2023 Notes”) (together, the “2023 Notes”). Avadel Finance Cayman Limited, a Cayman Islands exempted company and an indirect wholly-owned subsidiary of Avadel Pharmaceuticals plc (the “Issuer”), repaid, with cash on hand, the remaining $17,500 aggregate principal amount of its February 2023 Notes on the maturity date of February 1, 2023.

On March 29, 2023, the Issuer executed an agreement to exchange $96,188 of its $117,375 October 2023 Notes for a new series of 6.0% exchangeable notes due April 2027 (the “April 2027 Notes”) (the “2023 Exchange Transaction”). The remaining $21,187 aggregate principal amount of the October 2023 Notes will maintain a maturity date of October 2, 2023.

On March 29, 2023, the Company executed a royalty purchase agreement with RTW Investments, L.P. that could provide the Company up to $75,000 of royalty financing. The $75,000 of royalty financing will be accessible following achievement of certain regulatory and financial milestones, including final FDA approval and commercial launch of LUMRYZ.

In accordance with Accounting Standards Codification (“ASC”) 205-40, Going Concern, the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that these consolidated financial statements are issued. The Company has concluded that it does not currently have sufficient liquidity to meet its operating, debt service and capital requirements for the next twelve months following the date of this Annual Report, which include repayment of the $21,187 aggregate principal amount of the October 2023 Notes. These conditions and events raised substantial doubt about the Company’s ability to continue as a going concern within one year after the date that these audited consolidated financial statements are issued.

In response to these conditions and events, the Company is evaluating various financing strategies to obtain sufficient additional liquidity to meet its operating, debt service and capital requirements for the next twelve months following the date of this Annual Report. The potential sources of financing that the Company is evaluating include one or any combination of royalty financing (as described above), secured or unsecured debt, convertible debt and equity. The Company also currently has authorized and available the use of its at-the-market offering program (“ATM Program”), described in more detail within Note

13: Equity Instruments and Transactions, which could provide the Company up to approximately $93,200, net of commissions, if fully utilized. While the Company has the ability to utilize the ATM Program, it intends to pursue the other financing strategies described above. Based on the Company’s ability to raise funds through the ATM Program and its cash, cash equivalents and marketable securities as of December 31, 2022, the Company has concluded that it is probable that such proceeds would provide sufficient additional capital to meet the Company’s operating, debt service and capital requirements for the next twelve months following the date of this Annual Report. As a result, the Company has concluded that management’s plans are probable of being achieved to alleviate the substantial doubt about the Company’s ability to continue as a going concern.

The sources of financing described above that could be available to the Company and the timing and probability of obtaining sufficient capital depends, in part, on obtaining final FDA approval of LUMRYZ, resolving any legal and regulatory matters that could preclude the Company from launching LUMRYZ and future capital market conditions. If the Company’s current assumptions regarding timing of potential final approval, the timing of the launch of LUMRYZ or if there are any other changes or differences in current assumptions that negatively impact our financing strategy, the Company may have to further reduce expenditures or significantly delay, scale back or discontinue the development or commercialization of LUMRYZ in order to extend its cash resources.

Basis of Presentation. These consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“U.S. GAAP”). The consolidated financial statements include the accounts of the Company and all subsidiaries. All intercompany accounts and transactions have been eliminated.

Certain reclassifications are made to prior year amounts whenever necessary to conform with the current year presentation. Certain reclassifications have been made to the Consolidated Statement of Loss and the Consolidated Statements of Cash Flows for the fiscal year ended December 31, 2021 to condense line items of the same nature into a single line. This change does not affect previously reported net loss in the Consolidated Statement of Loss and or net cash flows used in operating activities in the Consolidated Statements of Cash Flows.

Research and Development (“R&D”). R&D expenses consist primarily of costs related to outside services, personnel expenses, clinical studies and other R&D expenses. Outside services and clinical studies costs relate primarily to services performed by clinical research organizations and related clinical or development manufacturing costs, materials and supplies, filing fees, regulatory support, and other third-party fees. Personnel expenses relate primarily to salaries, benefits and share-based compensation. Other R&D expenses primarily include overhead allocations consisting of various support and facilities-related costs. R&D expenditures are charged to operations as incurred. Raw materials used in the production of pre-clinical and clinical products are expensed as R&D costs.

Share-based Compensation. The Company accounts for share-based compensation based on the estimated grant-date fair value. The fair value of stock options is estimated using Black-Scholes option-pricing valuation models (“Black-Scholes model”). As required by the Black-Scholes model, estimates are made of the underlying volatility of Avadel stock, a risk-free rate and an expected term of the option or warrant. The Company estimates the expected term using a simplified method, as the Company does not have enough historical exercise data for a majority of such options upon which to estimate an expected term. The Company recognizes compensation cost, net of an estimated forfeiture rate, using the accelerated method over the requisite service period of the award.

Income Taxes. The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, the Company determines deferred tax assets and liabilities on the basis of the differences between the financial statement and tax bases of assets and liabilities by using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date.

The Company recognizes deferred tax assets to the extent that the Company believes that these assets are more likely than not to be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results

of recent operations. If the Company determines that it would be able to realize its deferred tax assets in the future in excess of their net recorded amount, the Company would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes. As of December 31, 2022, the Company's cumulative loss position was significant negative evidence in assessing the need for a valuation allowance on its deferred tax assets. Given the weight of objectively verifiable historical losses from operations, the Company recorded a full valuation allowance on its deferred tax assets. The Company will be able to reverse the valuation allowance when it has shown its ability to generate taxable income on a consistent basis in future periods. The valuation allowance does not have an impact on the Company's ability to utilize any net operating losses or other tax attributes to offset cash taxes payable as these items are still eligible to be used.

The Company records uncertain tax positions on the basis of a two-step process in which (1) the Company determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, the Company recognizes the largest amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority.

The Company recognizes interest and penalties related to unrecognized tax benefits in the income tax expense line in the consolidated statements of loss. Accrued interest and penalties are included on the related tax liability line in the consolidated balance sheets.

Marketable Securities. The Company’s marketable securities are considered to be available for sale and are carried at fair value, with unrealized gains and losses, net of taxes, reported as a component of accumulated other comprehensive loss in shareholders’ (deficit) equity, with the exception of unrealized gains and losses on equity instruments and allowances for expected credit losses, if any, which are reported in earnings in the current period. The cost of securities sold is based upon the specific identification method.

For available-for-sale debt securities in an unrealized loss position, the Company assesses whether it intends to sell or if it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value. If the criteria are not met, the Company evaluates whether the decline in fair value has resulted from a credit loss or other factors. In making this assessment, management considers, among other factors, the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of the cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded for the credit loss, limited by the amount that the fair value is less than the amortized costs basis.

Allowance for Credit Losses. Amounts owed to the Company are presented net of an allowance that includes as assessment of expected credit losses. An allowance for credit losses is established based on expected losses. Expected losses are estimated by reviewing individual accounts, considering aging, financial condition of the debtor, payment history, current and forecast economic conditions and other relevant factors. To the extent that the Company identifies that any individual customer's credit quality has deteriorated, the Company establishes allowances based on the individual risk characteristics of that customer. The Company makes concerted efforts to collect all outstanding balances due from customers; however, amounts are written off against the allowance when the related balances are no longer deemed collectible.

Goodwill. Goodwill represents the excess of the acquisition consideration over the fair value of assets acquired and liabilities assumed. The Company has determined that it operates in a single segment and have a single reporting unit associated with the development and commercialization of pharmaceutical products. The Company tests goodwill for impairment annually and when events or changes in circumstances indicate that the carrying value may not be recoverable. The Company determined that no impairment of goodwill existed at December 31, 2022 and 2021.

Long-Lived Assets. Long-lived assets include fixed assets and right of use assets at contract manufacturing organizations. Long-lived assets are reviewed for impairment whenever conditions indicate that the carrying value of the assets may not be fully recoverable. Such impairment tests are based on a comparison of the pretax undiscounted cash flows expected to be generated by the asset to the recorded value of the asset or other market-based value approaches. If impairment is indicated, the asset value is written down to its market value if readily determinable or its estimated fair value based on discounted cash flows. Any significant changes in business or market conditions that vary from current expectations could have an impact on the fair value of these assets and any potential associated impairment. Certain long-lived assets are amortized using the straight-line method over a five year useful life. Total amortization expense of long-lived assets for the year ended December 31, 2022 and 2021 was $391 and $0, respectively.

Lease Obligations. The Company determines if a contract is a lease at the inception of the arrangement. Right-of-use assets and operating lease liabilities are recognized at commencement date based on the present value of remaining lease payments over the lease term. For this purpose, the Company considers only payments that are fixed and determinable at the time of commencement. The Company reviews all options to extend, terminate, or purchase its right-of-use assets at the inception of the lease and will include these options in the lease term when they are reasonably certain of being exercised. Short term leases with an initial term of 12 months or less are not recorded on the balance sheet and the associated lease payments are recognized in the consolidated statements of loss on a straight-line basis over the lease term. The Company’s lease contracts do not provide a readily determinable implicit rate. The Company’s estimated incremental borrowing rate is based on information available at the inception of the lease. The Company’s lease agreements may contain variable costs such as common area maintenance, insurance, real estate taxes or other costs. Variable lease costs are expensed as incurred on the consolidated statements of loss.