In June 2005, the Company entered into a collaboration agreement with Astellas for the development and commercialization (but not manufacture) of roxadustat for the treatment of anemia in Japan (“Japan Agreement”). Under this agreement, Astellas paid license fees and other consideration totaling $40.1 million (such amounts were fully received as of February 2009). Under the Japan Agreement, the Company is also eligible to receive from Astellas an aggregate of approximately $132.5 million in potential milestone payments, comprised of (i) up to $22.5 million in milestone payments upon achievement of specified clinical and development milestone events (such amounts were fully received as of July 2016), (ii) up to $95.0 million in milestone payments upon achievement of specified regulatory milestone events, and (iii) up to approximately $15.0 million in milestone payments upon the achievement of specified commercial sales milestone. The Japan Agreement also provides for tiered payments based on net sales of product (as defined) in the low 20% range of the list price published by the Japanese Ministry of Health, Labour and Welfare, adjusted for certain elements, after commercial launch.

During the fourth quarter of 2020, the Japanese Ministry of Health, Labour and Welfare approved EVRENZO® (roxadustat) for the treatment of anemia of CKD in adult patients not on dialysis. This approval triggered a $15.0 million milestone payable to the Company by Astellas under the Japan Agreement. Accordingly, the consideration of $15.0 million associated with this milestone was included in the transaction price and allocated to performance obligations under the Japan Agreement in the fourth quarter of 2020, substantially all of which was recognized as revenue during the year ended December 31, 2020 from performance obligations satisfied or partially satisfied.

In September 2019, the Japanese Ministry of Health, Labour and Welfare approved EVRENZO® (generic name: roxadustat; tradename EVRENZO® in Japan) for the treatment of anemia associated with CKD in dialysis patients. This approval triggered a $12.5 million milestone payable to the Company by Astellas under the Japan Agreement. Accordingly, the consideration of $12.5 million associated with this milestone was included in the transaction price and allocated to performance obligations under the Japan Agreement in the third quarter of 2019, substantially all of which was recognized as revenue during the year ended December 31, 2019 from performance obligations satisfied or partially satisfied.

The aggregate amount of the considerations received under the Japan Agreement, through December 31, 2021 totals $105.1 million, excluding drug product revenue that is discussed separately below.

In 2018, FibroGen and Astellas entered into an amendment to the Japan Agreement that allows Astellas to manufacture roxadustat drug product for commercialization in Japan (the “Japan Amendment”). Under this amendment, FibroGen would continue to manufacture and supply roxadustat API to Astellas for the roxadustat commercial launch in Japan. The commercial terms of the Japan Agreement relating to the transfer price for roxadustat for commercial use remain substantially the same, reflecting an adjustment for the manufacture of drug product by Astellas rather than FibroGen. The related drug product revenue, as described in details under Drug Product Revenue section below, were $2.1 million, $4.3 million and $(36.3) million in the years ended December 31, 2021, 2020 and 2019, respectively.

In April 2006, the Company entered into a separate collaboration agreement with Astellas for the development and commercialization of roxadustat for the treatment of anemia in Europe, the Middle East, the Commonwealth of Independent States and South Africa (“Europe Agreement”). Under the terms of the Europe Agreement, Astellas paid license fees and other upfront consideration totaling $320.0 million (such amounts were fully received as of February 2009). The Europe Agreement also provides for additional development and regulatory approval milestone payments up to $425.0 million, comprised of (i) up to $90.0 million in milestone payments upon achievement of specified clinical and development milestone events (such amounts were fully received as of 2012), (ii) up to $335.0 million in milestone payments upon achievement of specified regulatory milestone events. Under the Europe Agreement, Astellas committed to fund 50% of joint development costs for Europe and North America, and all territory-specific costs. The Europe Agreement also provides for tiered payments based on net sales of product (as defined) in the low 20% range.

During the third quarter of 2021, the European Commission approved EVRENZO^® (roxadustat) for the treatment of adult patients with symptomatic anemia associated with CKD. Astellas has launched EVRENZO in Germany, the United Kingdom, the Netherlands, and Austria. This approval triggered a total of $120.0 million milestone payable to the Company by Astellas under the Europe Agreement. Accordingly, the consideration of $120.0 million associated with these milestones was included in the transaction price and allocated to performance obligations under the Europe Agreement, all of which was recognized as revenue during the year ended December 31, 2021 from performance obligations satisfied.

During the second quarter of 2019, the Company received positive topline results from analyses of pooled major adverse cardiovascular event (“MACE”) and MACE+ data from its Phase 3 trials evaluating roxadustat as a treatment for dialysis and non-dialysis CKD patients, enabling Astellas to prepare for a Marketing Authorization Application (“MAA”) submission to the European Medicines Agency in the second quarter of 2020, following the Company’s NDA submission to the FDA that was accepted for review in February 2020. The Company evaluated the two regulatory milestone payments associated with the planned MAA submission and concluded that these milestones became probable of being achieved in the second quarter of 2019. Accordingly, the total consideration of $130.0 million associated with these milestones was included in the transaction price and allocated to performance obligations under the Europe Agreement in the second quarter of 2019, of which $128.8 million was recognized as revenue during the year ended December 31, 2019 and immaterial amounts for the years ended December 31, 2021 and 2020, from performance obligations satisfied or partially satisfied. According to the Europe Agreement, these milestone payments are billable to Astellas upon the submission of an MAA, therefore this $130.0 million was an unbilled contract asset as of December 31, 2019, and billed to Astellas upon the submission of an MAA in the second quarter of 2020 with the total $130.0 million received during the same quarter.

The aggregate amount of the considerations received under the Europe Agreement through December 31, 2021 totals $660.0 million, excluding drug product revenue that is discussed separately below.

Under the Europe Agreement, Astellas has an option to purchase roxadustat bulk drug product in support of commercial supplies. The Company fulfilled an inventory transfer obligation under the terms of the Europe Agreement in the fourth quarter of 2020. During the first quarter of 2021, the Company entered into an Astellas EU Supply Agreement (“EU Supply Agreement”) under the Europe Agreement to define general forecast, order, supply and payment terms for Astellas to purchase roxadustat bulk drug product from FibroGen in support of commercial supplies. The Company transferred bulk drug product to Astellas as pre-commercial supply for process validation purposes during the first quarter and commercial product during the fourth quarter of 2021. The Company recognized the related fully burdened manufacturing costs of $1.0 million as drug product revenue during the year ended December 21, 2021, and recorded the consideration of $25.9 million from these inventory transfers as deferred revenue as of December 31, 2021. See details under Drug Product Revenue section below.

For each of the Astellas agreements, the Company has evaluated the promised services within the respective arrangements and has identified performance obligations representing those services and bundles of services that are distinct.

Promised services that were not distinct have been combined with other promised services to form a distinct bundle of promised services, with revenue being recognized on the bundle of services rather than the individual services. There are no right-of-return provisions for the delivered items in the Astellas agreements.

As of December 31, 2021, the transaction price for the Japan Agreement, excluding manufacturing services that is discussed separately below, included $40.1 million of non-contingent upfront payments, $65.0 million of variable consideration related to payments for milestones considered probable of being achieved, and $11.9 million of variable consideration related to co-development billings. The transaction price for the Europe Agreement, excluding manufacturing services that is discussed separately below, included $320.0 million of non-contingent upfront payments, $340.0 million of variable consideration related to payments for milestones considered probable of being achieved, and $219.9 million of variable consideration related to co-development billings.

For revenue recognition purposes, the Company determined that the term of each collaboration agreement with Astellas begins on the effective date and ends upon the completion of all performance obligations contained in the 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 requirement to continue funding development for a substantive period of time and loss of product rights, along with non-refundable upfront payments already remitted by Astellas, create significant disincentive for Astellas to exercise its right to terminate the agreements.

For the Astellas agreements, the Company allocated the transaction price to the various performance obligations based on the relative SSP of each performance obligation, with the exception of co-development billings allocated entirely to co-development services performance obligations.

For the technology license under the Japan Agreement and the Europe Agreement, SSP was determined primarily by using the discounted cash flow (“DCF”) method, which aggregates the present value of future cash flows to determine the valuation as of the effective date of each of the agreements. The DCF method involves the following key steps: 1) the determination of cash flow forecasts and 2) the selection of a range of comparative risk-adjusted discount rates to apply against the cash flow forecasts. The discount rates selected were based on expectations of the total rate of return, the rate at which capital would be attracted to the Company and the level of risk inherent within the Company. The discounts applied in the DCF analysis ranged from 17.5% to 20.0%. The Company’s cash flow forecasts were derived from probability-adjusted revenue and expense projections by territory. Such projections included consideration of taxes and cash flow adjustments. The probability adjustments were made after considering the likelihood of technical success at various stages of clinical trials and regulatory approval phases. SSP also considered certain future royalty payments associated with commercial performance of the Company’s compounds, transfer prices and expected gross margins.

The promised services that were analyzed, along with their general timing of satisfaction and recognition as revenue, are as follows:

Manufacturing rights. In the case of the Japan Agreement, the Company retained manufacturing rights largely because of the way the parties chose for FibroGen to be compensated under the agreement. At the time the agreement was signed, the Company believed that it was more advantageous upon commercialization to have a transfer price revenue model in place as opposed to a traditional sales-based model. The manufacturing process does not require specialized knowledge or expertise uniquely held by FibroGen, and notwithstanding contractual restrictions, Astellas could employ manufacturing services from readily available third parties in order to benefit from the license. Therefore, along with the foregoing paragraph, the Company determined that the license in Japan is a distinct performance obligation despite the retention of manufacturing rights by the Company.

In summary, the Company concludes that item (1) represents a performance obligation. The portion of the transaction price allocated to this performance obligation based on a relative SSP basis is recognized as revenue in its entirety at the point in time the license transfers to Astellas.

Items (2)-(5) are bundled into a single performance obligation that is distinct given the fact that all are highly interrelated during the development period (pre-commercial phase of development) such that satisfying them independently is not practicable. Revenue is recognized over time based on progress toward complete satisfaction of the performance obligation. The Company uses an input method to measure progress toward the satisfaction of the performance obligation, which is based on costs of labor hours or full time equivalents and out-of-pocket expenses incurred relative to total expected costs to be incurred. The measure of progress is updated each reporting period.

Under the Japan Amendment, the drug product revenue represents variable consideration and is estimated based on the quantity of product shipped, actual listed price for roxadustat issued by the Japanese Ministry of Health, Labour and Welfare and possible future changes to the listed price, adjusted for the timing of and estimated bulk product strength mix intended to be manufactured by Astellas, estimated cost to convert the API to bulk drug product tablets, and estimated yield from the manufacture of bulk product tablets, among others.

Under the Europe Agreement, the drug product revenue amount represents variable consideration and is estimated based on the quantity of product transferred and an estimated price. The estimated price is based on the contractual transfer price percentage applied on the estimated weighted average net sales price per strength, which is estimated to be realized by Astellas from the end sale of roxadustat in its approved territories.

Effective July 30, 2013, the Company entered into a collaboration agreement with AstraZeneca for the development and commercialization of roxadustat for the treatment of anemia in the U.S. and all other countries in the world, other than China, not previously licensed under the Astellas Europe and Astellas Japan Agreements (“U.S./RoW Agreement”). It also excludes China, which is covered by a separate agreement with AstraZeneca described below. Under the terms of the U.S./RoW Agreement, AstraZeneca paid upfront, non-contingent, non-refundable and time-based payments totaling $374.0 million (such amounts were fully received as of June 2016). Under the U.S./RoW Agreement, the Company is also eligible to receive from AstraZeneca an aggregate of approximately $875.0 million in potential milestone payments, comprised of (i) up to $65.0 million in milestone payments upon achievement of specified clinical and development milestone events, (ii) up to $325.0 million in milestone payments upon achievement of specified regulatory milestone events, (iii) up to $160.0 million in milestone payments related to activity by potential competitors and (iv) up to approximately $325.0 million in milestone payments upon the achievement of specified commercial sales events.

Under the U.S./RoW Agreement, the Company and AstraZeneca will equally share in the development costs of roxadustat not already paid for by Astellas, up to a total of $233.0 million (i.e. the Company’s share of development costs is $116.5 million, which was reached in 2015). Development costs incurred by FibroGen during the development period in excess of the $233.0 million (aggregated spend) are fully reimbursed by AstraZeneca. AstraZeneca will pay the Company tiered royalty payments on AstraZeneca’s future net sales (as defined in the agreement) of roxadustat in the low 20% range. In addition, the Company will receive a transfer price for shipment of commercial product based on a percentage of AstraZeneca’s net sales (as defined in the agreement) in the low- to mid-single digit range.

As mentioned above, during the second quarter of 2019, the Company received positive topline results from analyses of pooled MACE and MACE+ data from its Phase 3 trials for roxadustat, enabling the Company’s NDA submission to the FDA. The Company evaluated the regulatory milestone payment associated with this planned NDA submission and concluded that this milestone became probable of being achieved in the second quarter of 2019. Accordingly, the consideration of $50.0 million associated with this milestone was included in the transaction price and allocated to performance obligations under the combined arrangement in the second quarter of 2019, of which $42.4 million was recognized as revenue during the year ended December 31, 2019 and immaterial amounts were recognized as revenue during the years ended December 31, 2021 and 2020, from performance obligations satisfied or partially satisfied. This milestone was fully received in April 2020.

The aggregate amount of the considerations received under the U.S./RoW Agreement through December 31, 2021 totals $439.0 million, excluding drug product revenue that is discussed separately below. In 2020, the Company entered into Commercial Supply Agreement under the U.S./RoW Agreement with AstraZeneca to define general forecast, order, supply and payment terms for AstraZeneca to purchase roxadustat bulk drug product from FibroGen in support of commercial supplies. The Company shipped bulk drug product to AstraZeneca as commercial supply during 2020, and the first and second quarter of 2021. In August 2021, the FDA Issued a complete response letter regarding roxadustat’s NDA for the treatment of anemia due to CKD in adult patients, stating that it could not be approved in its present form. The Company evaluated the impact of these developments in revising its estimates of variable consideration associated with drug product revenue and updated the estimated transaction price, and recorded $11.2 million as deferred revenue as of December 31, 2021. See details under Drug Product Revenue section below.

Effective July 30, 2013, the Company (through its subsidiaries affiliated with China) entered into a collaboration agreement with AstraZeneca for the development and commercialization (but not manufacture) of roxadustat for the treatment of anemia in China (“China Agreement”). Under the terms of the China Agreement, AstraZeneca agreed to pay upfront consideration totaling $28.2 million (such amounts were fully received in 2014). Under the China Agreement, the Company is also eligible to receive from AstraZeneca an aggregate of approximately $348.5 million in potential milestone payments, comprised of (i) up to $15.0 million in milestone payments upon achievement of specified clinical and development milestone events, (ii) up to $146.0 million in milestone payments upon achievement of specified regulatory milestone events, and (iii) up to approximately $187.5 million in milestone payments upon the achievement of specified commercial sales and other events. The China Agreement is structured as a 50/50 profit or loss share (as defined), which was amended under the China Amendment discussed below in the third quarter of 2020, and provides for joint development costs (including capital and equipment costs for construction of the manufacturing plant in China), to be shared equally during the development period.

In December 2019, roxadustat has been included on the updated National Reimbursement Drug List (“NRDL”) released by China’s National Healthcare Security Administration for the treatment of anemia in CKD, covering patients who are non-dialysis dependent as well as those who are dialysis-dependent. The inclusion on the NRDL triggered a total of $22.0 million milestones payable to the Company by AstraZeneca. Accordingly, the total consideration of $22.0 million associated with these milestones was included in the transaction price and allocated to performance obligations under the combined arrangement, of which $18.7 million was recognized as revenue during the year ended December 31, 2019. This milestone payment was received during the first quarter of 2020. The Company continued to recognize related revenue during the years ended December 31, 2021 and 2020, from performance obligations satisfied or partially satisfied, and the amounts were not material.

The aggregate amount of the considerations received for milestone and upfront payments under the China Agreement through December 31, 2021 totals $77.2 million.

In July 2020, FibroGen Cayman, FibroGen Beijing, and FibroGen International (Hong Kong) Limited (collectively, “FibroGen China”) and AstraZeneca (together with FibroGen China, the “Parties”) entered into the China Amendment, effective July 1, 2020, relating to the development and commercialization of roxadustat in China. While the responsibilities of the Parties under the China Agreement remain largely the same, certain changes were made.

Under the China Amendment, in September 2020, FibroGen Beijing and AstraZeneca completed the establishment of a jointly owned entity, Falikang, which performs roxadustat distribution, as well as conduct sales and marketing through AstraZeneca.

Under the China Amendment, the interim period is defined as the period from April 1, 2020 to the time when Falikang is fully operational. Falikang became fully operational in January 2021. The calculation for profit or loss share related to sales of roxadustat in China has changed for the period from April 1, 2020 onwards. With effect from April 1, 2020, the Parties have changed the method under which commercial expenses incurred by AstraZeneca are calculated and billed. AstraZeneca’s co-promotion expenses for their sales and marketing efforts are now subject to a cap of a percentage of net sales. Once AstraZeneca has been fully reimbursed for their sales and marketing costs under the cap, AstraZeneca will bill the co-promotion expenses based on actual costs on a prospective basis. In addition, the China Amendment has allowed for a higher cost of manufacturing incurred by FibroGen Beijing to be included in the profit or loss share calculation, subject to an annual cap, among other changes.

As a result, the interim period during the year ended December 31, 2020 primarily included the following activities:

Since Falikang became fully operational in January 2021, substantially all direct roxadustat product sales to distributors in China are made by Falikang, while FibroGen Beijing continues to sell roxadustat product directly in a few provinces in China. FibroGen Beijing manufactures and supplies commercial product to Falikang based on a gross transaction price, which is adjusted for the estimated profit share. In addition, AstraZeneca now bills the co-promotion expenses to Falikang and to FibroGen Beijing, respectively, for its services provided to the respective entity. Development costs continue to be shared 50/50 between the Parties.

During the year ended December 31, 2021, the Company recognized $35.6 million of net product revenue from the sales to Falikang, as described in details under Product Revenue, Net section below.

In addition to sales to Falikang, during the year ended December 31, 2021, the Company recognized $12.1 million of net product revenue from sales directly to distributors in a few provinces in China, as described as direct sales under Product Revenue, Net section below.

The Company evaluated whether the U.S./RoW Agreement and the China Agreement should be accounted for as a single or separate arrangements and concluded that the agreements should be accounted for as a single arrangement with the presumption that two or more agreements executed with a single customer at or around the same time should be presumed to be a single arrangement. The key points the Company considered in reaching this conclusion are as follows:

Accordingly, as the agreements are being accounted for as a single arrangement, upfront and other non-contingent consideration received and to be received has been and will be pooled together and allocated to each of the performance obligations in both the U.S./RoW Agreement and the China Agreement based on their relative SSPs.

For each of the AstraZeneca agreements, the Company has evaluated the promised services within the respective arrangements and has identified performance obligations representing those services and bundled services that are distinct.

Promised services that were not distinct have been combined with other promised services to form a distinct bundle of promised services, with revenue being recognized on the bundle of services rather than the individual promised services. There are no right-of-return provisions for the delivered items in the AstraZeneca agreements.

As of December 31, 2021, the transaction price for the U.S./RoW Agreement and the China Agreement, excluding manufacturing services that is discussed separately below, included $402.2 million of non-contingent upfront payments, $114.0 million of variable consideration related to payments for milestones considered probable of being achieved, $610.9 million of variable consideration related to co-development billings, offset by $7.0 million of variable consideration related to profit share under the China Amendment.

For the AstraZeneca agreements, the Company allocated the transaction price to the various performance obligations based on the relative SSP of each performance obligation, with the exception of co-development billings and commercial sale of product. Co-development billings under the U.S./RoW Agreement were allocated entirely to the U.S./RoW co-development services performance obligation, and co-development billings under the China Agreement were allocated entirely to the combined performance obligation under the China Agreement. Commercial sale of product under the U.S./ROW Agreement is entirely allocated to the manufacturing commercial supply of products performance obligation, and commercial sale of product under the China Agreement is allocated entirely to the combined China performance obligation.

For revenue recognition purposes, the Company determined that the terms of its collaboration agreements with AstraZeneca begin on the effective date and end upon the completion of all performance obligations contained in the agreements. 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 requirement to continue funding development for a substantive period of time and the loss of product rights, along with non-refundable upfront payments already remitted by AstraZeneca, represent substantive termination penalties that create significant disincentive for AstraZeneca to exercise its right to terminate the agreement.

For the technology license under the AstraZeneca U.S./RoW Agreement, SSP was determined based on a two-step process. The first step involved determining an implied royalty rate that would result in the net present value of future cash flows to equal to zero (i.e. where the implied royalty rate on the transaction would equal the target return for the investment). This results in an upper bound estimation of the magnitude of royalties that a hypothetical acquirer would reasonably pay for the forecasted cash flow stream. The Company’s cash flow forecasts were derived from probability-adjusted revenue and expense projections. Such projections included consideration of taxes and cash flow adjustments. The probability adjustments were made after considering the likelihood of technical success at various stages of clinical trials and regulatory approval phases. The second step involved applying the implied royalty rate, which was determined to be 40%, against the probability-adjusted projected net revenues by territory and determining the value of the license as the net present value of future cash flows after adjusting for taxes. The discount rate utilized was 17.5%.

The promised services that were analyzed, along with their general timing of satisfaction and recognition as revenue, are as follows:

Items (2)-(4) are bundled into a single performance obligation that is distinct given the fact that all are highly interrelated during the development period (pre-commercial phase of development) such that delivering them independently is not practicable. Revenue is recognized over time based on progress toward complete satisfaction of the performance obligation. The Company uses an input method to measure progress toward the satisfaction of the performance obligation, which is based on costs of labor hours or full time equivalents and out-of-pocket expenses incurred relative to total expected costs to be incurred. The measure of progress is updated each reporting period.

The promised services that were analyzed are consistent with the U.S./RoW Agreement, except for license to the Company’s technology existing at the effective date of the agreement, described as follows:

For the China Agreement, the Company retained manufacturing rights as an essential part of a strategy to pursue domestic regulatory pathway for product approval, which requires the regulatory licensure of the manufacturing facility in order to commence commercial shipment. The prospects for the collaboration as a whole would have been substantially different had manufacturing rights been provided to AstraZeneca. The Company holds the rights to manufacture commercial drug product in China. Therefore, AstraZeneca cannot benefit from the license on its own or together with other readily available resources. Accordingly, all the promises identified, including the license, co-development services and manufacturing of commercial supplies, under the China Agreement have been bundled into a single performance obligation and amounts of the transaction price allocable to this performance obligation are deferred until control of the manufactured commercial drug product has begun to transfer to AstraZeneca.

In accordance with the China Amendment, once Falikang is fully operational, which commenced in January 2021, substantially all product sales will be made by Falikang directly to the distributors in China, while the Company continues to sell directly in a few provinces in China. Revenue is recognized at a point in time when control of roxadustat commercial product is transferred to Falikang. For the Company’s direct sales of commercial drug 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.

In July 2021, FibroGen exclusively licensed to Eluminex Biosciences (Suzhou) Limited (“Eluminex”) global rights to its investigational biosynthetic cornea derived from recombinant human collagen Type III.

Under the terms of the agreement with Eluminex (the “Eluminex Agreement”), Eluminex will make an $8.0 million upfront payment to FibroGen. In addition, FibroGen may receive up to a total of $64.0 million in future manufacturing, clinical, regulatory, and commercial milestone payments for the biosynthetic cornea program, as well as $36.0 million in commercial milestones for the first recombinant collagen III product that is not the biosynthetic cornea. FibroGen will also be eligible to receive mid single-digit to low double-digit royalties based upon worldwide net sales of cornea products, and low single-digit to mid single-digit royalties based upon worldwide net sales of other recombinant human collagen type III products that are not cornea products.

The Company accounted for this agreement under ASC 606 and identified one performance obligation at inception of the agreement related to the granting of the license rights to the investigational biosynthetic cornea derived from recombinant human collagen Type III. The Company based its assessment on the determination that Eluminex can benefit from the granted license on its own by developing and commercializing the underlying product using its own resources. All components of the transaction price in the agreement were allocated to the single performance obligation. Additionally, the Company will be responsible for supplying the cornea product at 110% of its product manufacturing costs until its manufacturing technology is fully transferred to Eluminex. Supply of the cornea product will be managed by a separate agreement and is considered a separate performance obligation.

During the year ended December 31, 2021, the $8.0 million upfront license payment was recognized as license revenue for the performance obligation satisfied. This amount was recorded as an unbilled contract asset as of December 31, 2021 in the prepaid expenses and other current assets in the consolidated balance sheets. The remaining future variable consideration related to future manufacturing, clinical, regulatory milestone payments as described above were fully constrained because the Company cannot conclude that it is probable that a significant reversal of the amount of cumulative revenue recognized will not occur, given the inherent uncertainties of success with these future milestones. For commercial milestones and royalties, the Company determined that the license is the predominant item to which the royalties or sales-based milestones relate and revenue will be recognized when the corresponding milestones and royalties are earned.

License Revenue and Development Revenue Recognized Under the Collaboration Agreements and License Agreement

License amounts identified below are included in the “License revenue” line item in the consolidated statements of operations. All other elements identified below are included in the “Development and other revenue” line item in the consolidated statements of operations.

Amounts recognized as license revenue and development revenue under the Japan Agreement with Astellas were as follows (in thousands):

		Years Ended December 31,
Agreement	Performance Obligation	2021		2020		2019
Japan	License revenue	$	—	$	14,323	$	11,935
	Development revenue	$	248	$	1,220	$	1,222

The transaction price related to consideration received and accounts receivable has been allocated to each of the following performance obligations under the Japan Agreement with Astellas, along with any associated deferred revenue as follows (in thousands):

Japan Agreement	Cumulative Revenue Through December 31, 2021		Deferred Revenue at December 31, 2021		Total Consideration Through December 31, 2021
License	$	100,347	$	—	$	100,347
Development revenue		16,598		—		16,598
Total license and development revenue	$	116,945	$	—	$	116,945

The revenue recognized under the Japan Agreement for the year ended December 31, 2021 included immaterial revenue resulting from changes to estimated variable consideration in the current year relating to performance obligations satisfied or partially satisfied in previous periods. The Company does not expect material variable consideration from estimated future co-development billing beyond development period in the transaction price related to the Japan Agreement.

Amounts recognized as license revenue and development revenue under the Europe Agreement with Astellas were as follows (in thousands):

		Years Ended December 31,
Agreement	Performance Obligation	2021		2020		2019
Europe	License revenue	$	108,434	$	—	$	117,470
	Development revenue	$	21,679	$	17,954	$	28,172

The transaction price related to consideration received and accounts receivable has been allocated to each of the following performance obligations under the Europe Agreement with Astellas, along with any associated deferred revenue as follows (in thousands):

Europe Agreement	Cumulative Revenue Through December 31, 2021		Deferred Revenue at December 31, 2021		Total Consideration Through December 31, 2021
License	$	596,385	$	—	$	596,385
Development revenue		270,641		—		270,641
Total license and development revenue	$	867,026	$	—	$	867,026

The revenue recognized under the Europe Agreement for the year ended December 31, 2021 included an increase in revenue of $1.0 million resulting from changes to estimated variable consideration in the current year relating to performance obligations satisfied or partially satisfied in previous periods. The remainder of the transaction price related to the Europe Agreement includes $12.9 million of variable consideration from estimated future co-development billing and is expected to be recognized over the remaining development service period.

Amounts recognized as license revenue and development revenue under the U.S./RoW and China Agreements with AstraZeneca were as follows (in thousands):

		Years Ended December 31,
Agreement	Performance Obligation	2021		2020			2019
U.S. / RoW and China	License revenue	$	—	$	—		$	47,681
	Development revenue		48,345		61,508			84,629
	China performance obligation	$	—	$	(90	)	$	90

The transaction price related to consideration received and accounts receivable has been allocated to each of the following performance obligations under the U.S./RoW Agreement and China Agreement, along with any associated deferred revenue as follows (in thousands):

U.S. / RoW and China Agreements	Cumulative Revenue Through December 31, 2021		Deferred Revenue at December 31, 2021			Total Consideration Through December 31, 2021
License	$	341,844	$	—		$	341,844
Co-development, information sharing & committee services		603,119		—			603,119
China performance obligation *		35,568		171,516			207,084
Total license and development revenue	$	980,531	$	171,516	**	$	1,152,047

The revenue recognized under the U.S./RoW Agreement and China Agreement for the year ended December 31, 2021 included a reduction in revenue of $4.8 million resulting from changes to estimated variable consideration in the current year relating to performance obligations satisfied or partially satisfied in previous periods. The remainder of the transaction price related to the U.S./RoW Agreement and China Agreement includes $30.9 million of variable consideration from estimated future co-development billing and is expected to be recognized over the remaining development service period, except for amounts allocated to the China performance obligation. The amount allocated to the China performance obligation is expected to be recognized as the Company transfers control of the commercial drug product to Falikang.

Amounts recognized as revenue under the Eluminex were as follows (in thousands):

Product revenue, net from the sales of roxadustat commercial product in China was as follows (in thousands):

	Years Ended December 31,
	2021			2020			2019
Direct Sales:
Gross revenue	$	13,727		$	89,027			2,803
Price adjustment		(982	)		—			(936	)
Non-key account hospital listing award		95			(9,325	)		—
Contractual sales rebate		(832	)		(6,189	)		(149	)
Other discounts and rebates		(21	)		(923	)		(18	)
Sales returns		83			(92	)		—
Direct sales revenue, net		12,070			72,498			1,700

Sales to Falikang:
Gross transaction price		97,531			—			—
Profit share		(34,759	)		—			—
Net transaction price		62,772			—			—
Increase in deferred revenue		(27,204	)		—			—
Sales to Falikang revenue, net		35,568			—			—
Total product revenue, net	$	47,638		$	72,498		$	1,700

Product revenue from direct roxadustat product sales to distributors in China is recognized in an amount that reflects the consideration that the Company expects to be entitled to in exchange for those products, net of sales rebates and discounts.

The total discounts and rebates were $1.7 million, $16.4 million and $1.1 million for the years ended December 31, 2021, 2020 and 2019, respectively. The discounts and rebates for the years ended December 31, 2021 and 2019 primarily consisted of $1.0 million and $0.9 million, respectively, of price adjustments recorded based on government-listed price guidance and estimated channel inventory levels. The discounts and rebates also consisted of the contractual sales rebate calculated based on the stated percentage of gross sales by each distributor in the distribution agreement entered between FibroGen and each distributor. The contractual sales rebate was $0.8 million, $6.2 million and $0.1 million, respectively, for the years ended December 31, 2021, 2020 and 2019. In addition, in the second quarter of 2020, the Company amended the agreement with its pharmaceutical distributors, which triggered accounting modifications particularly related to the non-key account hospital listing award. For the year ended December 31, 2020, the non-key account hospital listing award was $9.3 million, which was recorded as a reduction to the revenue and calculated based on eligible non-key account hospital listings to date achieved by each distributor with certain requirements met during the period. All other rebates and discounts, including sales return allowance were immaterial for the periods presented.

The rebates and discounts that the Company’s pharmaceutical distributors have earned are eligible to be applied against future sales orders, 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 in the same period that the related revenue is recorded. Due to the distributor’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 calculated at the individual distributor level. The following table includes a roll-forward of the related contract liabilities (in thousands):

As of December 31, 2021 and 2020, the total contract liabilities was $3.2 million and $15.1 million, respectively, which was included in accrued and other current liabilities in the consolidated balance sheet. As of December 31, 2021 and 2020, the total rebates and discounts reflected as reductions to gross accounts receivable for direct sales was $1.1 million and $0.5 million, respectively.

Since Falikang became fully operational in January 2021, substantially all direct roxadustat product sales to distributors in China are made by Falikang. FibroGen Beijing manufactures and supplies commercial product to Falikang. The net transaction price for FibroGen Beijing’s product sales to Falikang is based on a gross transaction price, which is adjusted to account for the 50/50 profit share for the period.

The roxadustat sales to Falikang marked the beginning of the Company’s China performance obligation under the Company’s agreements with AstraZeneca. Product revenue is based on the transaction price of the China performance obligation. Revenue is recognized when control of the product is transferred to Falikang, in an amount that reflects the allocation of the transaction price to the performance obligation satisfied during the reporting period. Any net transaction price in excess of the revenue recognized is added to the deferred balance to date, and will be recognized over future periods as the performance obligations are satisfied. During the year ended December 31, 2021, following updates to its estimates, the Company deferred $27.2 million from the net transaction price to Falikang, which was included in the related deferred revenue of the China performance obligation.

The following table includes a roll-forward of the related deferred revenue that is considered as a contract liability (in thousands):

Deferred revenue includes amounts allocated to the China performance obligation under the AstraZeneca arrangement as revenue recognition associated with this unit of accounting is tied to the commercial launch of the products within China and to when the control of the manufactured commercial products is transferred to AstraZeneca. As of December 31, 2021, approximately $10.6 million of the deferred revenue related to the China unit of accounting was included in short-term deferred revenue, which represents the amount of deferred revenue associated with the China unit of accounting that is expected to be recognized within the next 12 months, associated with the commercial sales in China.

The reductions to gross accounts receivable related to product revenue to Falikang was $13.4 million as of December 31, 2021.

	Years Ended December 31,
	2021			2020		2019
Astellas	$	3,186		$	4,281	$	(36,324	)
AstraZeneca		(2,224	)		4,625		—
Drug product revenue	$	962		$	8,906	$	(36,324	)

During the second quarter of 2020, the Company fulfilled shipment obligations under the terms of Japan Amendment with Astellas, and recognized related drug product revenue of $8.2 million in the same period.

During the years ended December 31, 2021, 2020 and 2019, the Company updated its estimate of variable consideration related to the API shipments fulfilled under the terms of the Japan Amendment with Astellas in 2018 and 2020, and recorded an adjustment to the drug product revenue of $2.1 million, $(4.0) million and $(36.3) million for the years ended December 31, 2021, 2020 and 2019, respectively. Specifically, the change in estimated variable consideration was based on the API held by Astellas at the period end, adjusted to reflect the changes in the estimated bulk product strength mix intended to be manufactured by Astellas, estimated cost to convert the API to bulk product tablets, and estimated yield from the manufacture of bulk product tablets, among others.

During the fourth quarter of 2021, the Company transferred bulk drug product for commercial purposes under the terms of the Europe Agreement and the EU Supply Agreement with Astellas, and recognized the related fully burdened manufacturing costs of $1.0 million as drug product revenue, and recorded $8.3 million as deferred revenue as of December 31, 2021, due to a high degree of uncertainty associated with the final consideration. During the first quarter of 2021, the Company transferred bulk drug product from process validation supplies for commercial purposes under the terms of the Europe Agreement and the EU Supply Agreement with Astellas. The Company recorded the consideration of $11.8 million from this inventory transfer as deferred revenue as of December 31, 2021, due to a high degree of uncertainty associated with the final consideration. During the fourth quarter of 2020, the Company transferred bulk drug product from process validation supplies for commercial purposes under the terms of the Europe Agreement with Astellas. As a result, the Company recorded $6.0 million as deferred revenue as of December 31, 2020, due to a high degree of uncertainty associated with the final consideration. The Company recognized royalty revenue of $0.2 million from this deferred revenue during the year ended December 31, 2021. The remainder of the deferred revenue will be recognized as and when uncertainty is resolved.

During the fourth quarter of 2021, the Company updated its estimate of variable consideration related to the bulk drug product inventory transfers fulfilled under the terms of the Europe Agreement and the EU Supply Agreement with Astellas, and recorded an unbilled contract asset of $49.8 million, which was offset by related deferred revenue under the Europe Agreement and EU Supply Agreement. Specifically, the change in estimated variable consideration was based on the bulk drug product held by Astellas at the period end, adjusted to reflect the changes in the estimated transfer price, among others.

During the first half of 2021 and during the year ended December 31, 2020, the Company shipped bulk drug product to AstraZeneca as commercial supply under the terms of the Master Supply Agreement. Based on the complete response letter issued by the FDA in August 2021, the Company evaluated the impact of these developments in revising its estimates of variable consideration associated with drug product revenue. As a result, the Company updated the estimated transaction price for these shipments, and recorded $11.2 million as deferred revenue as of December 31, 2021.

The following table includes a roll-forward of the above-mentioned deferred revenues that are considered as contract liabilities related to drug product (in thousands):

	Balance at December 31, 2020			Additions			Recognized as Revenue		Balance Presented Net Against Contract Asset		Balance at December 31, 2021
Astellas - Japan Agreement	$	—		$	(1,974	)	$	—	$	—	$	(1,974	)
Astellas - Europe Agreement		(5,984	)		(69,874	)		179		49,788		(25,891	)
AstraZeneca - U.S. Agreement		—			(11,171	)		—		—		(11,171	)
Drug product revenue - deferred revenue	$	(5,984	)	$	(83,019	)	$	179	$	49,788	$	(39,036	)