Use of Estimates—The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The Company bases its estimates and judgments on historical experience and on various other assumptions. The amounts of assets and liabilities reported in the Company's balance sheets and the amounts of revenues and expenses reported for each period presented are affected by estimates and assumptions, which are used for, but not limited to, the accounting for revenue allowances, stock-based compensation, income taxes, loss contingencies, acquisition related intangibles including in process research and development (IPR&D) and goodwill, fair value of contingent consideration, and accounting for research and development costs. Actual results could differ from those estimates.

Marketable Securities—Marketable securities consists of available-for-sale investments in US Treasury Notes with an original maturity of greater than 90 days. Marketable securities under this classification are recorded at fair value and unrealized gains and losses are recorded within accumulated other comprehensive (loss) income. The estimated fair value of available-for-sale marketable securities is determined based on quoted market prices. Marketable securities maturing in one year or less are classified as current assets and marketable securities maturing in more than one year are classified as non-current assets. The Company did not have available-for-sale securities with a maturity of more than one year as of December 31, 2023. As of December 31, 2022, management did not expect the Company's available-for-sale securities with a maturity of more than one year to be sold or redeemed within the next year and therefore has classified the marketable securities as long-term assets in the consolidated balance sheet.

Fixed Assets, Net—Fixed assets are recorded at cost and are depreciated on a straight-line basis over the estimated useful lives of the assets. Estimated useful lives of three years to five years are used for computer equipment. Estimated useful lives of seven years are used for laboratory equipment, office equipment, manufacturing equipment and furniture and fixtures. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset.

Impairment Assessment—The Company reviews the recoverability of its finite-lived intangible assets and long-lived assets for indicators of impairments. Events or circumstances that may require an impairment assessment include negative clinical trial results, a significant decrease in the market price of the asset, or a significant adverse change in legal factors or the manner in which the asset is used. If such indicators are present, the Company assesses the recoverability of affected assets by determining if the carrying value of such assets is less than the sum of the undiscounted future cash flows of the assets. If such assets are found to not be recoverable, the Company measures the amount of the impairment by comparing the carrying value of the assets to the fair value of the assets. The Company determined that no indicators of impairment of finite-lived intangible assets or long-lived assets existed at December 31, 2023.

Business Combinations and Asset Acquisitions—The Company evaluates acquisitions of assets and other similar transactions to assess whether or not the transaction should be accounted for as a business combination or asset acquisition by first applying a screen to determine if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or group of similar identifiable assets. If the screen is met, the transaction is accounted for as an asset acquisition. If the screen is not met, further determination is required as to whether or not the Company has acquired inputs and processes that have the ability to create outputs, which would meet the requirements of a business. If determined to be a business combination, the Company accounts for the transaction under the acquisition method of accounting as indicated in Accounting Standards Update (ASU) 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business, which requires the acquiring entity in a business combination to recognize the fair value of all assets acquired, liabilities assumed, and any non-controlling interest in the acquiree and establishes the acquisition date as the fair value measurement point. Accordingly, the Company recognizes assets acquired and liabilities assumed in business combinations, including contingent assets and liabilities, and non-controlling interest in the acquiree based on the fair value estimates as of the date of acquisition. In accordance with ASC 805, Business Combinations, the Company recognizes and measures goodwill as of the acquisition date, as the excess of the fair value of the consideration paid over the fair value of the identified net assets acquired.

The consideration for the Company’s business acquisitions may include future payments that are contingent upon the occurrence of a particular event or events. The obligations for such contingent consideration payments are recorded at fair value on the acquisition date. The contingent consideration obligations are then evaluated each reporting period. Changes in the fair value of contingent consideration, other than changes due to payments, are recognized as a gain or loss and recorded within change in the fair value of deferred and contingent consideration liabilities in the consolidated statements of comprehensive loss.

If determined to be an asset acquisition, the Company accounts for the transaction under ASC 805-50, which requires the acquiring entity in an asset acquisition to recognize assets acquired and liabilities assumed based on the cost to the acquiring entity on a relative fair value basis, which includes transaction costs in addition to consideration given. No gain or loss is recognized as of the date of acquisition unless the fair value of non-cash assets given as consideration differs from the assets’ carrying amounts on the acquiring entity’s books. Consideration transferred that is non-cash will be measured based on either the cost (which shall be measured based on the fair value of the consideration given) or the fair value of the assets acquired and liabilities assumed, whichever is more reliably measurable. Goodwill is not recognized in an asset acquisition and any excess consideration transferred over the fair value of the net assets acquired is allocated to the identifiable assets based on relative fair values. If the in-licensed agreement for IPR&D does not meet the definition of a business and the assets have not reached technological feasibility and therefore have no alternative future use, the Company expenses payments made under such license agreements as acquired IPR&D expense in its consolidated statements of comprehensive loss.

Contingent consideration payments in asset acquisitions are recognized when the contingency is resolved and the consideration is paid or becomes payable, unless the contingent consideration meets the definition of a derivative, in which case the amount becomes part of the basis in the asset acquired. None of the Company's contingent consideration met the definition of a derivative. Upon recognition of the contingent consideration payment, the amount is included in the cost of the acquired asset or group of assets.

Indefinite-lived Intangible Assets—Indefinite-lived intangible assets consist of IPR&D. IPR&D acquired directly in a transaction other than a business combination is capitalized if the projects will be further developed or have an alternative future use; otherwise, they are expensed. The fair values of IPR&D project assets acquired in business combinations are capitalized. The Company generally utilizes the Multi-Period Excess Earning Method to determine the estimated fair value of the IPR&D assets acquired in a business combination. The projections used in this valuation approach are based on many factors, such as relevant market size, patent protection, and expected pricing and industry trends. The estimated future net cash flows are then discounted to the present value using an appropriate discount rate. These assets are treated as indefinite-lived intangible assets until completion or abandonment of the projects, at which time the assets are amortized over the remaining useful life or written off, as appropriate. Intangible assets with indefinite lives, including IPR&D, are tested for impairment if impairment indicators arise and, at a minimum, annually. However, an entity is permitted to first assess qualitative factors to determine if a quantitative impairment test is necessary. Further testing is only required if the entity determines, based on the qualitative assessment, that it is more likely than not that an indefinite-lived intangible asset’s fair value is less than its carrying amount. The indefinite-lived intangible asset impairment test consists of a one-step analysis that compares the fair value of the intangible asset with its carrying amount. If the carrying amount of an intangible asset exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. The Company considers many factors in evaluating whether the value of its intangible assets with indefinite lives may not be recoverable, including, but not limited to, expected growth rates, the cost of equity and debt capital, general economic conditions, the Company’s outlook and market performance of the Company’s industry and recent and forecasted financial performance. The Company performs a qualitative test for its indefinite-lived intangible assets annually as of October 1. During the year ended December 31, 2023, the Company concluded that no impairment exists.

Goodwill—Goodwill represents the amount of consideration paid in excess of the fair value of net assets acquired as a result of the Company’s business acquisitions accounted for using the acquisition method of accounting. Goodwill is not amortized and is subject to impairment testing at a reporting unit level on an annual basis or when a triggering event occurs that may indicate the carrying value of the goodwill is impaired. An entity is permitted to first assess qualitative factors to determine if a quantitative impairment test is necessary. Further testing is only required if the entity determines, based on the qualitative assessment, that it is more likely than not that the fair value of the reporting unit is less than its carrying amount. The Company reassesses its reporting units as part of its annual segment review. As of December 31, 2023, the Company concluded that it continues to operate as one reporting unit. As of October 1, 2023, the Company's single reporting unit for purposes of its goodwill impairment test had a negative carrying value and the Company performed a qualitative impairment test for goodwill. During the year ended December 31, 2023, the Company concluded that no impairment exists.

Leases—A lease is a contract, or part of a contract, that conveys the right to control the use of explicitly or implicitly identified property, plant or equipment in exchange for consideration. Control of an asset is conveyed to the Company if the Company obtains the right to obtain substantially all of the economic benefits of the asset or the right to direct the use of the asset. The Company recognizes right-of-use (ROU) assets and lease liabilities at the lease commencement date based on the present value of future, fixed lease payments over the term of the arrangement. ROU assets are amortized on a straight-line basis over the term of the lease or are amortized based on consumption, if this approach is more representative of the pattern in which benefit is expected to be derived from the underlying asset. Lease liabilities accrete to yield and are reduced at the time

Leases are measured at present value using the rate implicit in the lease or, if the implicit rate is not determinable, the lessee's implicit borrowing rate. As the implicit rate is not typically available, the Company uses its implicit borrowing rate based on the information available at the lease commencement date to determine the present value of future lease payments. The implicit borrowing rate approximates the rate the Company would pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments. See Note 9 - Leases for further details.

Foreign Currency—The Company has operations in the US, France, Germany, Ireland, Italy, the Netherlands, Switzerland, the UK, and Japan. The results of the Company's non-US dollar based functional currency operations are translated to US dollars at the average exchange rates during the period. Assets and liabilities are translated at the exchange rate prevailing at the balance sheet date. Equity is translated at the prevailing exchange rate at the date of the equity transaction. Translation adjustments are included in shareholders' (deficit) equity, as a component of accumulated other comprehensive (loss) income.

Derivatives—In the normal course of business, the Company is exposed to the effects of interest rate changes. The Company may enter into derivative instruments, including interest rate swaps and caps, to manage or hedge interest rate risk. Derivative instruments are recorded at fair value on the balance sheet date. The Company has not elected hedge accounting treatment for the changes in the fair value of derivatives. Changes in the fair value of derivatives are recorded each period and are included in change in fair value of interest rate swap in the consolidated statements of comprehensive loss and consolidated statements of cash flows.

Concentration of Credit Risk—Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company places its cash equivalents with high credit-quality financial institutions and may invest its short-term investments in US treasury securities, mutual funds and government agency bonds. The Company has established guidelines relative to credit ratings and maturities that seek to maintain safety and liquidity.

The Company is exposed to risks associated with extending credit to customers related to the sale of products. The Company does not require collateral to secure amounts due from its customers. The Company uses an expected loss methodology to calculate allowances for trade receivables. The Company's measurement of expected credit losses is based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. The Company does not currently have a material allowance for uncollectible trade receivables. The following table presents the percentage of gross product revenue represented by the Company's three largest customers as of the year ended December 31, 2023 and their respective percentages for the year ended December 31, 2022.

Inventory and Cost of Product Revenues (excluding amortization of intangible assets)—Inventory is stated at the lower of cost and net realizable value. Inventory is sold on a first-in, first-out (FIFO) basis. The Company periodically reviews inventory for expiry and obsolescence and, if necessary, writes down accordingly. If quality specifications are not met during the manufacturing process, such inventory is written off to cost of product revenues (excluding amortization of intangible assets) in the period identified.

Research and Development—R&D expenses consist primarily of salaries, benefits and other related costs, including stock-based compensation, for personnel serving in the Company's research and development functions, including medical affairs. R&D expense also includes other internal operating expenses, the cost of manufacturing a product candidate, including the medical devices for drug delivery, for clinical study, the cost of conducting clinical studies, and the cost of conducting preclinical and research activities. In addition, R&D expenses include payments to third parties for the license rights to products in development (prior to marketing approval), such as brensocatib, and may include the cost of asset acquisitions (as described further above). The Company's expenses related to manufacturing its product candidates and medical devices for clinical study are primarily related to activities at CMOs that manufacture its clinical product supply of ARIKAYCE, brensocatib, TPIP and early-stage research. The Company's expenses related to clinical trials are primarily related to activities at CROs that conduct and manage clinical trials on the Company's behalf. These contracts set forth the scope of work to be completed at a fixed fee or amount per patient enrolled. Payments under these contracts primarily depend on performance criteria such as the successful enrollment of patients or the completion of clinical trial milestones as well as time-based fees. Expenses are accrued based on contracted amounts applied to the level of patient enrollment and to activity according to the clinical trial protocol. Nonrefundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized. Such amounts are then recognized as an expense as the related goods are delivered or the services are performed, or when the goods or services are no longer expected to be provided.

Stock-based Compensation—The Company recognizes stock-based compensation expense for awards of equity instruments to employees and directors based on the grant-date fair value of those awards. The grant-date fair value of the award is recognized as compensation expense ratably over the requisite service period, which generally equals the vesting period of the award. The Company may also grant performance-based stock options and performance stock units (PSUs) to employees from time to time. The grant-date fair value of performance-based stock options is recognized as compensation expense over the implicit service period using the accelerated attribution method once it is probable that the performance condition will be achieved. The grant-date fair value of performance stock units is recognized as compensation expense on the date the performance conditions become probable, with an initial recording of the cumulative expense that would have been recognized if the PSU expense had been recognized on a straight-line basis since the date of grant. The remaining unamortized fair value of the awards will then be expensed prospectively on a straight-line basis over the remaining service period. Stock-based compensation expense is included in both R&D and SG&A expenses in the consolidated statements of comprehensive loss.

Income Taxes—The Company accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss carry forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date.

The Company may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by taxing authorities, based solely on the technical merits of the position. The tax benefits recognized in the financial statements from such a position should be measured based on the largest benefit that is more likely than not to be sustained upon ultimate settlement. As any adjustment to the Company’s uncertain tax positions would not result in a cash tax liability, it has not recorded any accrued interest or penalties related to its uncertain tax positions.

Net Loss Per Share—Basic net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by the weighted average number of common shares and other dilutive securities outstanding during the period. Potentially dilutive securities from stock options, restricted stock (RS), restricted stock units (RSUs), PSUs and convertible debt securities would be anti-dilutive as the Company incurred a net loss. Potentially dilutive common shares resulting from the assumed exercise of outstanding stock options and from the assumed conversion of the Company's convertible notes are determined based on the treasury stock method.

The following table sets forth the reconciliation of the weighted average number of shares used to compute basic and diluted net loss per share for the years ended December 31, 2023, 2022 and 2021.


	Years Ended December 31,
	2023		2022		2021
	(in thousands, except per share amounts)
Numerator:
Net loss	$	(749,567)	$	(481,534)	$	(434,654)
Denominator:
Weighted average common shares used in calculation of basic net loss per share:	140,433		123,035		112,111
Effect of dilutive securities:
Common stock options	—		—		—
RS and RSUs	—		—		—
PSUs	—		—		—
Convertible debt securities	—		—		—
Weighted average common shares outstanding used in calculation of diluted net loss per share	140,433		123,035		112,111
Net loss per share:
Basic and diluted	$	(5.34)	$	(3.91)	$	(3.88)

Segment Information—The Company currently operates in one business segment, which is the development and commercialization of therapies for patients with rare diseases. The Company has a single management team that reports to the Chief Executive Officer, the chief operating decision maker, who comprehensively manages the entire business. The Company does not operate separate lines of business with respect to its products or product candidates. Accordingly, the Company has one reportable segment.

Recently Adopted Accounting Pronouncements—In August 2020, the Financial Accounting Standards Board (FASB) issued ASU 2020-06, Debt — Accounting for Convertible Instruments, to reduce the complexity associated with applying GAAP to certain financial instruments with characteristics of liabilities and equity. For convertible instruments, the number of accounting models for convertible debt instruments is reduced, which results in fewer embedded conversion features being separately recognized from the host contract as compared with current GAAP. Only convertible instruments that meet the definition of a derivative or are issued with substantial premiums will continue to be subject to the separation models. ASU 2020-06 is effective for fiscal years beginning after December 15, 2021. A modified retrospective and a fully retrospective transition method are both permitted. The Company transitioned using the modified retrospective method. The impact of adopting ASU 2020-06 on January 1, 2022 resulted in an opening balance sheet adjustment increasing debt by approximately $221.9 million and issuance costs classified to debt by approximately $6.1 million, decreasing the deferred tax liability by $1.4 million, as well as an increase to retained earnings of approximately $50.2 million, with an offsetting reduction to additional paid-in-capital of $264.6 million, net of tax.

Recent Accounting Pronouncements (Not Yet Adopted)—In December 2023, the FASB issued ASU 2023-09 Income Taxes—Improvements to Income Tax Disclosures, in order to enhance the transparency and decision usefulness of income tax disclosures. ASU 2023-09 requires greater disaggregation of income tax disclosures related to the income tax rate reconciliation and income taxes paid. ASU 2023-09 will be effective for fiscal years beginning after December 15, 2024. The Company is currently evaluating the impact of adoption of ASU 2023-09 on its consolidated financial statements.