Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The 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, its wholly owned subsidiaries and its majority-owned subsidiaries, as well as any variable interest entity (“VIE”) for which FibroGen is the primary beneficiary. All inter-company transactions and balances have been eliminated in consolidation. For any VIE for which FibroGen is not the primary beneficiary, the Company uses the equity method of accounting.

The Company operates in one reportable segment — the development and commercialization of novel therapeutics to treat serious unmet medical needs.

The Company believes that its existing cash and cash equivalents, short-term investments and accounts receivable will be sufficient to meet its anticipated cash requirements for at least the next 12 months from the date of issuance of the financial statements. However, the Company may need additional capital thereafter and its liquidity assumptions may materially differ. The Company may utilize its available financial resources sooner than it currently expects and may incur additional expenses not currently contemplated. In addition, the Company may elect to raise additional funds at any time through equity, equity-linked, debt financing arrangements or from other sources.

Foreign Currency Translation

The reporting currency of the Company and its subsidiaries is the U.S. dollar.

The functional currency of FibroGen Europe is the Euro. The functional currency of FibroGen (China) Medical Technology Development Co., Ltd. (“FibroGen Beijing”) is CNY. As such, monetary assets and liabilities of FibroGen Europe and FibroGen Beijing in currencies other than their functional currencies are remeasured using exchange rates in effect at the end of the period. The assets and liabilities of FibroGen Europe and FibroGen Beijing are translated to U.S. dollars at exchange rates in effect at the balance sheet date. All income statement accounts are translated at monthly average exchange rates. Resulting foreign currency translation adjustments are recorded directly in accumulated other comprehensive income (loss) as a separate component of stockholders’ equity (deficit).

The functional currency of FibroGen, Inc. and all other subsidiaries is the U.S. dollar. Accordingly, monetary assets and liabilities in the non-functional currency of these subsidiaries are remeasured using exchange rates in effect at the end of the period. Revenues and costs in local currency are remeasured using average exchange rates for the period, except for costs related to those balance sheet items that are remeasured using historical exchange rates. The resulting remeasurement gains and losses are included within interest income and other, net in the consolidated statements of operations as incurred and have not been material for all periods presented.

Use of Estimates

The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting period. The more significant areas requiring the use of management estimates and assumptions include valuation and recognition of revenue and deferred revenue, specifically, estimates in variable consideration for drug product sales, and estimates in transaction price per unit for the China performance obligation (as defined and discussed under Revenue Recognition below). On an ongoing basis, management reviews these estimates and assumptions. Changes in facts and circumstances may alter such estimates and actual results could differ from those estimates.

Concentration of Credit Risk

The Company is subject to risks associated with concentration of credit for cash and cash equivalents. Outside of short-term operating needs, the majority of cash on hand is invested in U.S. treasuries, corporate bonds, commercial paper and money market funds. Any remaining cash is deposited with major financial institutions primarily in the U.S., China and the Cayman Islands. At times, such deposits may be in excess of insured limits. The Company has not experienced any loss on its deposits of cash and cash equivalents. Included in current assets are significant balances of accounts receivable as follows:


	December 31,
	2023			2022
Falikang — Related party		42	%		65	%
AstraZeneca		33	%		16	%

As of December 31, 2023 and 2022, the aggregate accounts receivable related to roxadustat sales in China from distributors represented 17% and 10%, respectively, of the consolidated accounts receivable, with no material balance from any individual distributor.

Other Risks and Uncertainties

The Company’s future results of operations involve a number of risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, the results of clinical trials and the achievement of milestones, research developments, actions by regulatory authorities, market acceptance of the Company’s product candidates, competition from other products and larger companies, the liquidity and capital resources of the Company, intellectual property protection for the Company's proprietary technology, strategic relationships, and dependence on key individuals, suppliers, clinical organization, and other third parties.

Cash, Cash Equivalents and Restricted Time Deposits

The Company considers all highly liquid investments with maturities of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents also include money market accounts and various deposit accounts. As of December 31, 2023 and 2022, a total of $32.2 million and $92.5 million, respectively, of the Company’s cash and cash equivalents was held outside of the U.S. in the Company’s foreign subsidiaries to be used primarily for the Company’s China operations. Restricted time deposits include an irrevocable standby letter of credit as security deposit for a long-term property lease with the Company’s landlord. Restricted time deposits were $1.7 million and $2.1 million as of December 31, 2023 and 2022, respectively.

Investments

As of December 31, 2023, the Company’s investments consist primarily of diversified bonds, commercial paper, and money market funds. Those investments with original maturities of greater than three months and remaining maturities of less than 12 months (365 days) are considered short-term investments. Those investments with maturities greater than 12 months (365 days) from the balance sheet date are considered long-term investments. When such investments are held, the Company’s investments classified as available-for-sale are recorded at fair value based upon quoted market prices at period end. Unrealized gains and losses for available-for-sale debt investments that are deemed temporary in nature are recorded in accumulated other comprehensive income (loss) as a separate component of stockholder’ equity. Realized and unrealized gains or losses resulting from changes in value and sale of the Company’s marketable equity investments are recorded in other income (expenses) in the consolidated statement of operations.

A decline in the fair value of any security below cost that is deemed other than temporary results in a charge to earnings and the corresponding establishment of a new cost basis for the security. Premiums and discounts are amortized (accreted) over the life of the related security as an adjustment to its yield. Dividend and interest income are recognized when earned. Realized gains and losses are included in earnings and are derived using the specific identification method for determining the cost of investments sold.

Trade accounts receivable

The allowance for credit losses is based on the Company’s assessment of the collectability of customer accounts. The Company makes estimates of expected credit losses for the allowance for doubtful accounts by considering factors such as historical experience, credit quality, the age of the accounts receivable balances, current economic and regulatory conditions that may affect a customer’s ability to pay, and estimates of expected future losses. The Company’s bad debt expense for the years ended December 31, 2023, 2022 and 2021 and the allowance for credit losses as of December 31, 2023 and 2022 were immaterial.

Credit losses – Available-for-sale debt securities

The Company periodically assesses its available-for-sale investments for other-than-temporary impairment. For debt securities in an unrealized loss position, the Company first considers its intent to sell, or whether it is more likely than not that the Company will be required to sell the debt securities before recovery of their amortized cost basis. If either of these criteria are met, the amortized cost basis of such debt securities is written down to fair value through interest and other, net.

For debt securities in an unrealized loss position that do not meet the aforementioned criteria, the Company assesses whether the decline in the fair value of such debt securities has resulted from credit losses or other factors. The Company considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and any adverse conditions specifically related to the securities, among other factors. If this assessment indicates that a credit loss may exist, the Company then compares the present value of cash flows expected to be collected from such securities to their amortized cost basis. If the present value of 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 through interest and other, net, limited by the amount that the fair value is less than the amortized cost basis. Any additional impairment not recorded through an allowance for credit losses is recognized in other comprehensive income.

Changes in the allowance for credit losses are recorded as provision for, or reversal of, credit loss expense. Losses are charged against the allowance when the Company believes that an available-for-sale security is confirmed uncollectable or when either of the criteria regarding intent or requirement to sell is met.

Inventories

Inventories are stated at the lower of cost or net realizable value, on a first-in, first-out, or FIFO, basis. The cost of the Company’s inventories in China is determined using full absorption and standard costing method. The Company reviews the standard cost of raw materials, work-in-process and finished goods annually and more often as appropriate to ensure that its inventories approximate current actual cost. The cost of the Company’s inventories in the U.S. uses actual costs to determine its cost basis. The cost of inventories includes direct material cost, direct labor and manufacturing overhead.

When the technical feasibility of the Company’s future commercialization is considered probable and the future economic benefit is expected to be realized, based on management’s judgment, the Company capitalizes pre-launch inventory costs prior to regulatory approval. A number of factors are considered, including the status in the validation process in significant jurisdictions, regulatory application and approval process, and terms and condition for future sale of such inventory or future alternative use. The pre-launch inventory cost includes purchase cost of raw materials, cost paid to contract manufacturers for inventory manufacturing, freight and custom charges, and certain direct internal labor and overhead expenses.

The Company periodically reviews its inventories to identify obsolete, slow-moving, excess or otherwise unsaleable items. If obsolete, excess or unsaleable items are observed and there are no alternate uses for the inventory, an inventory valuation adjustment is recorded through a charge to cost of goods sold on the Company’s consolidated statements of operations. Inventory valuation adjustments require judgment including consideration of many factors, such as estimates of future product demand and product expiration period, among others.

Property and Equipment

Property and equipment are recorded at cost and depreciated over their estimated useful lives using the straight-line method. Computer equipment, laboratory equipment, machinery and furniture and fixtures are depreciated over three to five years. Leasehold improvements are recorded at cost and amortized over the term of the lease or their useful life, whichever is shorter.

Equity method investment - Variable Interest Entity

Under the Accounting Standards Codification (“ASC”) 810, Consolidation (“ASC 810”), when the Company obtains an economic interest in an entity, it evaluates the entity to determine if it should be deemed a VIE, and, if so, whether the Company is the primary beneficiary and is therefore required to consolidate the VIE, based on significant judgment whether the Company (i) has the power to direct the activities that most significantly impact the economic performance of the VIE and (ii) has the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the VIE.

On an ongoing basis, the Company re-evaluates the VIE assessment based on potential changes in facts and circumstances, including but not limited to, the shareholder loans to the entity and the execution of any future significant agreements between the entity and its shareholders and/or other third parties.

Leases

The Company determines if an arrangement is or contains a lease at inception date when it is given control of the underlying assets. The Company elected the practical expedient not to apply the lease recognition and measurement requirements to short-term leases, which is any lease with a term of 12 months or less as of the commencement date that does not include an option to purchase the underlying asset that the lessee is reasonably certain to exercise.

Lease right-of-use (“ROU”) assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. As its leases do not typically provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of future payments. The Company reassesses the incremental borrowing rate periodically for application to any new leases or lease modifications, which approximates the rate at which the Company would borrow, on a secured basis, in the country where the lease was executed. For any lease modification, the Company reassesses the lease classification, remeasures the related lease liability using an updated discount rate, and adjusts the related ROU asset under the lease modification guidance under the ASC 842, Leases, (“ASC 842”).

Lease ROU assets include any lease payments made and initial direct costs incurred. The Company has lease agreements with lease and non-lease components. The Company generally accounts for each lease component separately from the non-lease components, and excludes all non-lease components from the calculation of minimum lease payments in measuring the ROU asset and lease liability.

The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease terms.

Regarding leases denominated in a foreign currency, the related ROU assets and the corresponding ROU asset amortization costs are remeasured using the exchange rate in effect at the date of initial recognition; the related lease liabilities are remeasured using the exchange rate in effect at the end of the reporting period; the lease costs and interest expenses related to lease liability accretion are remeasured using average exchange rates for the reporting period.

Finance leases are included in finance lease ROU assets, finance lease liabilities, current and non-current on the Company’s consolidated balance sheets. Operating leases are included in operating lease ROU assets, operating lease liabilities, current and non-current on the Company’s consolidated balance sheets.

Impairment of Long-Lived Assets

The Company continually evaluates whether events or circumstances have occurred that indicate that the estimated remaining useful life of its long-lived assets may warrant revision or that the carrying value of these assets may be impaired. If the Company determines that an impairment trigger has been met, the Company evaluates the realizability of its long-lived assets (asset group) based on a comparison of projected undiscounted cash flows from use and eventual disposition with the carrying value of the related asset. Any write-downs (which are measured based on the difference between the fair value and the carrying value of the asset) are treated as permanent reductions in the carrying amount of the assets (asset group). Based on this evaluation, the Company believes that, as of each of the balance sheet dates presented, none of the Company’s long-lived assets were impaired. The Company had no impairment of long-lived assets for the years ended December 31, 2023, 2022 and 2021.

Liability Related to Sale of Future Revenues

The Company accounts for the sale of future revenue as a debt, because the risks and rewards to the investor are limited by the terms of the transaction as discussed further in Note 10, Liability Related to Sale of Future Revenues. The difference between the carrying amount of the initial liability and the gross proceeds received is accounted for as a discount. The Company recognizes interest expense based on an estimated effective annual interest rate, which is affected by the amount and timing of revenues recognized and changes in the timing of forecasted revenues. Quarterly, the Company reassesses the expected revenues and the timing of such revenues, recalculates the amortization and effective interest rate and adjusts the accounting prospectively as needed.

Asset Acquisition

The Company evaluates acquisitions of entities or assets to assess whether or not the transaction should be accounted for as a business combination or asset acquisition by first applying a screen test to determine whether 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 this screen criteria is met, the transaction is accounted for as an asset acquisition. If not, 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 definition of a business. The Company measures and recognizes asset acquisitions that are not deemed to be business combinations based on the cost to acquire the assets, which includes transaction costs.

In an asset acquisition, the cost allocated to acquire in-process research and development (“IPR&D”) with no alternative future use is charged to research and development expense at the acquisition date. The Company recognizes assets acquired and liabilities assumed in asset acquisitions, including contingent assets and liabilities, and non-controlling interests (“NCI”) in the acquired assets at their estimated fair values as of the date of acquisition.

An NCI represents the non-affiliated equity interest in the underlying entity or asset. The Company presents redeemable NCI in its consolidated statements of changes in equity within mezzanine equity. Nonredeemable NCI and redeemable NCI are initially recorded at their fair values. Subsequently, net loss in the underlying entity or asset is only allocated to nonredeemable NCI. Net income in the underlying entity or asset is allocated to nonredeemable NCI and redeemable NCI based on their respective stated rights.

Revenue Recognition

Revenues under collaboration agreements

The Company’s collaboration agreements include multiple performance obligations comprised of promised services, or bundles of services, that are distinct. Services that are not distinct are combined with other services in the agreement until they form a distinct bundle of services. The Company’s process for identifying performance obligations and an enumeration of each obligation for each agreement is outlined in Note 3, Collaboration Agreements, License Agreement and Revenues. Determining the performance obligations within a collaboration agreement often involves significant judgment and is specific to the facts and circumstances contained in each agreement.

The Company has identified the following material promises under its collaboration agreements: (1) license of FibroGen technology, (2) the performance of co-development services, including manufacturing of clinical supplies and other services during the development period, and (3) manufacture of commercial supply. The evaluation as to whether these promises are distinct, and therefore represent separate performance obligations, is described in more detail in Note 3, Collaboration Agreements, License Agreement and Revenues.

For revenue recognition purposes, the Company determines that the terms of its collaboration agreements begin on the effective date and end upon the completion of all performance obligations contained in the agreements. In each agreement, the contract term is defined as the period in which parties to the contract have present and enforceable rights and obligations. The Company believes that the existence of what it considers to be substantive termination penalties on the part of the counterparty create sufficient incentive for the counterparty to avoid exercising its right to terminate the agreement.

The transaction price for each collaboration agreement is determined based on the amount of consideration the Company expects to be entitled for satisfying all performance obligations within the agreement. The Company’s collaboration agreements include payments to the Company of one or more of the following: non-refundable upfront license fees; co-development billings; development, regulatory, and commercial milestone payments; payments from sales of active pharmaceutical ingredient (“API”); payments from sales of bulk drug product and royalties on net sales of licensed products.

Upfront license fees are non-contingent and non-refundable in nature and are included in the transaction price at the point when the license fees become due to the Company. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the customer and the transfer of the promised goods or services to the customer will be one year or less.

Co-development billings resulting from the Company’s research and development efforts, which are reimbursable under its collaboration agreements, are considered variable consideration. Determining the reimbursable amount of research and development efforts requires detailed analysis of the terms of the collaboration agreements and the nature of the research and development efforts incurred. Prior to CKD approval in the third quarter of 2021, determining the amount of variable consideration from co-development billings required the Company to make estimates of future research and development efforts, which involved significant judgment. Co-development billings are allocated entirely to the co-development services performance obligation when amounts are related specifically to research and development efforts necessary to satisfy the performance obligation, and such an allocation is consistent with the allocation objective.

Milestone payments are also considered variable consideration, which requires the Company to make estimates of when achievement of a particular milestone becomes probable. Similar to other forms of variable consideration, milestone payments are included in the transaction price when it becomes probable that such inclusion would not result in a significant revenue reversal. Milestones are therefore included in the transaction price when achievement of the milestone becomes probable.

For arrangements that include sales-based royalties and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, royalty revenue resulting from its collaboration arrangements was immaterial.

The transaction price is allocated to performance obligations based on their relative standalone selling price (“SSP”), with the exception of co-development billings allocated entirely to co-development services performance obligations. The SSP is determined based on observable prices at which the Company separately sells the products and services. If an SSP is not directly observable, then the Company will estimate the SSP considering marketing conditions, entity-specific factors, and information about the customer or class of customer that is reasonably available. The process for determining SSP involves significant judgment and includes consideration of multiple factors, including assumptions related to the market opportunity and the time needed to commercialize a product candidate pursuant to the relevant license, estimated direct expenses and other costs, which include the rates normally charged by contract research and contract manufacturing organizations for development and manufacturing obligations, and rates that would be charged by qualified outsiders for committee services.

Significant judgment may be required in determining whether a performance obligation is distinct, determining the amount of variable consideration to be included in the transaction price, and estimating the SSP of each performance obligation. An enumeration of the Company’s significant judgments is outlined in Note 3, Collaboration Agreements, License Agreement and Revenues.

For each performance obligation identified within an arrangement, the Company determines the period over which the promised services are transferred and the performance obligation is satisfied. Service revenue that was recognized over time was based on progress toward complete satisfaction of the performance obligation. For each performance obligation satisfied over time, the Company assesses the proper method to be used for revenue recognition, either an input method to measure progress toward the satisfaction of services or an output method of determining the progress of completion of performance obligation.

Revenue under license agreements

Under a license agreement, if the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenues from upfront license fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company determines whether the combined performance obligation is satisfied over time or at a point in time. If the combined performance obligation is satisfied over time, the Company uses judgment in determining the appropriate method of measuring progress for purposes of recognizing revenue from the up-front license fees. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition.

Product revenue, net

Product revenue, net consists of revenues from sales of roxadustat commercial product to Falikang, and directly to pharmaceutical distributors located in one province in China that are not covered by Falikang. Falikang is jointly owned by AstraZeneca AB (“AstraZeneca”) and FibroGen Beijing. The Company is not the primary beneficiary of Falikang for accounting purposes, as AstraZeneca is the final decision maker for all the roxadustat commercialization activities, and the Company lacks the power criterion to direct the activities of Falikang (see Note 5, Equity method investment - Variable Interest Entity).

Sales to Falikang

Falikang became fully operational in January 2021, at which time FibroGen Beijing began selling roxadustat commercial product to Falikang. Falikang is FibroGen Beijing’s primary customer in China and substantially all roxadustat product sales to distributors in China are made by Falikang. Falikang bears inventory risk once it receives and accepts the product from FibroGen Beijing, and is responsible for delivering product to its distributors.

The promises identified under the AstraZeneca China Agreement (as defined in Note 3, Collaboration Agreements, License Agreement and Revenues), including the license, co-development services and manufacturing of commercial supplies have been bundled into a single performance obligation (“China performance obligation”). Amounts of the transaction price allocable to this performance obligation under the Company’s agreements with AstraZeneca as outlined in Note 3, Collaboration Agreements, License Agreement and Revenues, are deferred until control of the manufactured commercial product is transferred to AstraZeneca.

The initiation of roxadustat sales to Falikang marked the beginning of the China performance obligation. Revenue is recognized at a point in time when control of roxadustat commercial product is transferred to Falikang. Revenue is recognized based on the estimated transaction price per unit and actual quantity of product delivered during the reporting period. Specifically, the transaction price per unit is determined based on the overall transaction price over the total estimated sales quantity for the estimated performance period in which the Company determined it is likely those sales would occur. The price per unit is subject to reassessment on a quarterly basis, which may result in cumulative catch up adjustments due to changes in estimates.

The overall transaction price for FibroGen Beijing’s product sales to Falikang includes the following elements of consideration:

•

Non-refundable upfront license fees; development, regulatory, and commercial milestone payments based on the AstraZeneca China Agreement allocated to the China performance obligation;

•

Co-development billings resulting from the Company’s research and development efforts, which are reimbursable under the AstraZeneca China Agreement;

•

Interim profit/loss share between FibroGen Beijing and AstraZeneca from April 1, 2020 through December 31, 2020; and

•

Net transaction price from product sales to Falikang from January 1, 2021 onwards. The net transaction price includes the following elements:

Gross transaction price: The gross transaction price is based on a percentage of Falikang’s net sales to its distributors, which takes into account Falikang’s operating expenses and its payments to AstraZeneca for roxadustat sales and marketing efforts, capped at a percentage of Falikang’s net roxadustat sales.

Profit share: The gross transaction price is then adjusted for an estimated amount to achieve the 50/50 profit share from current period roxadustat net sales in China. The adjustments to date have been a reduction to the transaction price and the related accounts receivable from Falikang.

The non-refundable upfront license fees constitute a fixed consideration. The remainder of the above are variable consideration components, which may be constrained, and included in the transaction price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period when the uncertainty associated with the variable consideration is subsequently resolved. The calculation of the above variable consideration includes significant assumptions such as total sales quantity, performance period, gross transaction price and profit share, which require significant judgment.

Any net transaction price in excess of the revenue recognized is deferred, and will be recognized over future periods as the performance obligations are satisfied.

Direct Sales to Distributors

The Company sells roxadustat in China directly to a number of pharmaceutical distributors located in one province in China that are not covered by Falikang. These pharmaceutical distributors are the Company’s customers. Hospitals order roxadustat through a distributor and the Company ships the product directly to the distributors. The delivery of roxadustat to a distributor represents a single performance obligation. Distributors are responsible for delivering product to end users, primarily hospitals. Distributors bear inventory risk once they receive and accept the product. Product revenue is recognized when control of the promised good is transferred to the customer in an amount that reflects the consideration that the Company expects to be entitled to in exchange for the product.

The period between the transfer of control of the promised goods and when the Company receives payment is based on 60-day payment terms. As such, product revenue is not adjusted for the effects of a significant financing component.

Product revenue is recorded at the net sales prices that includes certain estimates of variable consideration. These estimates include price adjustment calculated based on estimated channel inventory levels when China’s National Healthcare Security Administration releases price guidance for roxadustat under the National Reimbursement Drug List, various fixed-amount or percentage-based rebates and discounts recorded as a reduction to revenue at the point of sale to the distributor or when distributor meets eligibility requirements, and estimated sales return as distributors can request to return product to the Company only due to quality issues or for product purchased within one year prior to the product’s expiration date.

The calculation of the variable consideration is based on gross sales to the distributor, or estimated utilizing best available information from the distributor, maximum known exposures and other available information including estimated channel inventory levels and estimated sales made by the distributor to hospitals, which involve a significant judgment.

The rebates and discounts all together are eligible to be applied against the distributor’s future sales order, limited to certain maximums until such rebates and discounts are exhausted. These rebates and discounts are recorded as contract liabilities at the time they become eligible and in the same period that the related revenue is recorded. Due to the Company’s legal right to offset, at each balance sheet date, the rebates and discounts are presented as reductions to gross accounts receivable from the distributor, or as a current liability to the distributor to the extent that the total amount exceeds the gross accounts receivable or when the Company expects to settle the discount in cash. The Company’s legal right to offset is determined at the individual distributor level. The contract liabilities were included in accrued and other current liabilities in the consolidated balance sheet. The rebates and discounts reflected as reductions to gross accounts receivable for direct sales.

Drug product revenue

Drug product revenue includes commercial-grade API or bulk drug product sales to AstraZeneca and Astellas Pharma Inc. (“Astellas”) in support of pre-commercial preparation prior to the New Drug Application (“NDA”) or Marketing Authorization Application approval, and to Astellas for ongoing commercial activities in Japan and Europe. Drug product revenue is recognized when the Company fulfills the inventory transfer obligations.

The amount of variable consideration that is included in the transaction price may be constrained, and is included in the drug product revenue only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period when the uncertainty associated with the variable consideration is subsequently resolved. Estimating variable consideration and the related constraint requires the use of significant management judgment. The Company reviews new information that may affect its variable consideration estimate at every reporting period and records revenue adjustment, if certain and material. Actual amounts of consideration ultimately received in the future may differ from the Company’s estimates, for which the Company will adjust these estimates and affect the drug product revenue in the period such variances become known.

As each of the Company’s collaboration agreements provide for annual true up to the considerations paid for its commercial supplies, the Company will re-evaluate the transaction price in each reporting period and record adjustment to revenue as uncertain events are resolved or other changes in circumstances occur.

License Acquisition Agreement

In June 2021, the Company entered into an exclusive license and option agreement (the “HiFiBiO Agreement”) with HiFiBiO Therapeutics (“HiFiBiO”), pursuant to which the Company exclusively licensed all product candidates in HiFiBiO’s Galectin-9 program and subsequently exclusively licensed all product candidates in HiFiBiO’s CCR8 program in December 2021. Under the terms of the HiFiBiO Agreement, the Company has paid a $25.0 million upfront payment to HiFiBiO during the year ended December 31, 2021, and recorded a $35.0 million upfront payment for the CCR8 option exercise in accrued liabilities as of December 31, 2021, which was paid during the first quarter of 2022. HiFiBiO may receive R&D and regulatory milestone payments of up to $175 million, as well as sales milestones of up to $170 million. HiFiBiO will also be eligible to receive tiered royalties based upon worldwide net sales capped at 10%, subject to certain reductions. We expect to file INDs on product candidates for both the CCR8 and Galectin-9 programs in the first half of 2024.

The acquisition of these licenses was accounted for as an asset acquisition. The above-mentioned upfront payments of $60.0 million related to the license and options acquisition meets the definition of an in-process research and development asset (“IPR&D asset”) under the ASC 730, Research and Development. They relate to particular research and development projects and are determined to have no alternative future uses and thus have no separate economic value. Therefore, these upfront payments were recorded as research and development expenses during the year ended December 31, 2021, and the cash payments were reflected as investing activities in the consolidated statement of cash flows during the years ended December 31, 2022 and 2021, respectively.

Contingent consideration payments will be evaluated and recognized when they become probable and reasonably estimable. The related IPR&D asset will only be capitalized if it has an alternative future use other than in a particular research and development project. Otherwise, amounts allocated to IPR&D asset that have no alternative use will be expensed. As of December 31, 2023, the contingencies related to the milestone payments had not been resolved, therefore no contingent consideration was recognized. The Company will reassess the probability of future option payments and contingent payments on a quarterly basis.

Research and Development Expenses

Research and development expenses consist of above-mentioned expense for acquired IPR&D asset, independent research and development costs and the gross amount of costs associated with work performed under collaboration agreements. Research and development costs include employee-related expenses, expenses incurred under agreements with clinical research organizations, other clinical and preclinical costs and allocated direct and indirect overhead costs, such as facilities costs, information technology costs and other overhead. All research and development costs are expensed as incurred.

Clinical Trial Accruals

Clinical trial costs are a component of research and development expenses. The Company accrues and expenses clinical trial activities performed by third parties based upon actual work completed in accordance with agreements established with clinical research organizations and clinical sites. The Company determines the costs to be recorded based upon validation with the external service providers as to the progress or stage of completion of trials or services and the agreed-upon fee to be paid for such services.

Selling, General and Administrative Expenses

Selling, general and administrative (“SG&A”) expenses consist primarily of employee-related expenses for executive, operational, finance, legal, compliance and human resource functions. SG&A expenses also include facility-related costs, professional fees, accounting and legal services, other outside services including co-promotional expenses associated with our commercialization efforts in China, recruiting fees and expenses associated with obtaining and maintaining patents.

Restructuring Charge

A restructuring charge is recognized when the liability is incurred and accrued in the period in which it is probable that the employees are entitled to the restructuring benefits and the amounts can be reasonably estimated. The restructuring liability accrued but not paid at the end of the reporting period is included in accrued and other current liabilities in the consolidated balance sheets.

Income Taxes

The Company utilizes the asset and liability method of accounting for income taxes, which requires the recognition of deferred tax assets and liabilities for expected future consequences of temporary differences between the financial reporting and income tax bases of assets and liabilities using enacted tax rates. Management makes estimates, assumptions and judgments to determine the Company’s provision for income taxes and for deferred tax assets and liabilities, and any valuation allowances recorded against the Company’s deferred tax assets. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent the Company believes that recovery is not likely, the Company must establish a valuation allowance.

The calculation of the Company’s current provision for income taxes involves the use of estimates, assumptions and judgments while taking into account current tax laws, interpretation of current tax laws and possible outcomes of future tax audits. The Company has established reserves to address potential exposures related to tax positions that could be challenged by tax authorities. Although the Company believes its estimates, assumptions and judgments to be reasonable, any changes in tax law or its interpretation of tax laws and the resolutions of potential tax audits could significantly impact the amounts provided for income taxes in the Company’s consolidated financial statements.

The calculation of the Company’s deferred tax asset balance involves the use of estimates, assumptions and judgments while taking into account estimates of the amounts and type of future taxable income. Actual future operating results and the underlying amount and type of income could differ materially from the Company’s estimates, assumptions and judgments thereby impacting the Company’s financial position and results of operations.

The Company has adopted ASC 740-10, Accounting for Uncertainty in Income Taxes, that prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of uncertain tax positions taken or expected to be taken in the Company’s income tax return, and also provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosure and transition.

The Company includes interest and penalties related to unrecognized tax benefits within income tax expense in the Consolidated Statements of Operations.

Stock-Based Compensation

The Company maintains equity incentive plans under which equity awards are granted to employees, which are comprised of stock options, service-based restricted stock units (“RSUs”), performance-based RSUs (“PRSUs”), and total shareholder return (“TSR”) awards.

The Company measures and recognizes compensation expense for all stock options, RSUs and PRSUs granted to its employees and directors based on the estimated fair value of the award on the grant date. The Company uses the Black-Scholes valuation model to estimate the fair value of stock option awards. The determination of the grant date fair value of options using the Black-Scholes valuation model is affected by the Company’s estimated common stock fair value and requires management to make a number of assumptions including the expected life of the option, the volatility of the underlying stock, the risk-free interest rate and expected dividends. The Company determines the fair value of RSUs and PRSUs using the fair value of our common stock on the date of grant. To estimate the fair value of the TSR awards, the Company uses the Monte Carlo valuation model to simulate the probabilities of achievement, which requires management to make a number of assumptions including 30-day average price, volatility of the underlying stock and the Company’s peers, and the risk-free interest rate.

The compensation cost of service-based stock options and restricted stock units is recognized net of any estimated forfeitures on a straight-line basis over the employee requisite service period. Compensation cost for PRSUs is expensed over the respective vesting periods when the achievement of performance criteria is probable. Compensation cost for the TSR awards is recognized over the requisite service period, regardless of when, if ever, the market condition is satisfied.

The Company believes that the fair value of stock options granted to non-employees is more reliably measured than the fair value of the services received.

Comprehensive Income (Loss)

The Company is required to report all components of comprehensive income (loss), including net loss, in the consolidated financial statements in the period in which they are recognized. Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on investments and foreign currency translation adjustments. Comprehensive gains (losses) have been reflected in the consolidated statements of comprehensive income (loss) for all periods presented.

Recently Issued Accounting Guidance Not Yet Adopted

In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which requires all public entities, including public entities with a single reportable segment, to provide in interim and annual periods one or more measures of segment profit or loss used by the chief operating decision maker to allocate resources and assess performance. In addition, this guidance requires disclosures of significant segment expenses and other segment items as well as incremental qualitative disclosures. This guidance is effective for fiscal years beginning after December 15, 2023, and interim periods after December 15, 2024, with retrospective application required, and early adoption permitted. The Company is currently in the process of evaluating the effects of this guidance on its related disclosures.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires enhanced income tax disclosures, including specific categories and disaggregation of information in the effective tax rate reconciliation, disaggregated information related to income taxes paid, income or loss from continuing operations before income tax expense or benefit, and income tax expense or benefit from continuing operations. This guidance is effective for annual periods beginning after December 15, 2024, with early adoption permitted. The Company is currently in the process of evaluating the impact of this pronouncement on its related disclosures.