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HZNP Horizon Therapeutics

Document and Entity Information

Document and Entity Information - shares3 Months Ended
Mar. 31, 2021Apr. 29, 2021
Cover [Abstract]
Document Type10-Q
Amendment Flagfalse
Document Period End DateMar. 31,
2021
Document Fiscal Year Focus2021
Document Fiscal Period FocusQ1
Title of 12(b) SecurityOrdinary shares, nominal value $0.0001 per share
Trading SymbolHZNP
Security Exchange NameNASDAQ
Entity Registrant NameHORIZON THERAPEUTICS PUBLIC LIMITED COMPANY
Entity Central Index Key0001492426
Entity Tax Identification Number00-0000000
Entity Current Reporting StatusYes
Entity Interactive Data CurrentYes
Current Fiscal Year End Date--12-31
Entity Filer CategoryLarge Accelerated Filer
Entity Small Businessfalse
Entity Emerging Growth Companyfalse
Entity Common Stock, Shares Outstanding224,768,551
Entity Shell Companyfalse
Entity File Number001-35238
Entity Incorporation, State or Country CodeL2
Entity Address, Address Line OneConnaught House, 1st Floor
Entity Address, Address Line Two1 Burlington Road
Entity Address, City or TownDublin 4
Entity Address, Postal Zip CodeD04 C5Y6
Entity Address, CountryIE
City Area Code011
Local Phone Number353 1 772 2100
Document Quarterly Reporttrue
Document Transition Reportfalse

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
CURRENT ASSETS:
Cash and cash equivalents $ 811,609 $ 2,079,906
Restricted cash3,839 3,573
Accounts receivable, net443,172 659,701
Inventories, net238,306 75,283
Prepaid expenses and other current assets334,442 251,945
Total current assets1,831,368 3,070,408
Property and equipment, net201,857 189,037
Developed technology and other intangible assets, net3,210,221 1,782,962
In-process research and development880,000
Goodwill1,076,388 413,669
Deferred tax assets, net589,618 560,841
Other assets57,158 55,699
Total assets7,846,610 6,072,616
CURRENT LIABILITIES:
Accounts payable42,986 37,710
Accrued expenses389,626 485,567
Accrued trade discounts and rebates325,232 352,463
Long-term debt—current portion16,000
Total current liabilities773,844 875,740
LONG-TERM LIABILITIES:
Long-term debt, net2,562,517 1,003,379
Deferred tax liabilities, net524,407 66,474
Other long-term liabilities131,072 101,672
Total long-term liabilities3,217,996 1,171,525
COMMITMENTS AND CONTINGENCIES
SHAREHOLDERS’ EQUITY:
Ordinary shares, $0.0001 nominal value; 600,000,000 shares authorized at March 31, 2021 and December 31, 2020; 225,027,621 and 221,721,674 shares issued at March 31, 2021 and December 31, 2020, respectively; and 224,643,255 and 221,337,308 shares outstanding at March 31, 2021 and December 31, 2020, respectively22 22
Treasury stock, 384,366 ordinary shares at March 31, 2021 and December 31, 2020(4,585)(4,585)
Additional paid-in capital4,199,823 4,245,945
Accumulated other comprehensive loss(1,253)(145)
Accumulated deficit(339,237)(215,886)
Total shareholders’ equity3,854,770 4,025,351
Total liabilities and shareholders' equity $ 7,846,610 $ 6,072,616

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / sharesMar. 31, 2021Dec. 31, 2020
Statement Of Financial Position [Abstract]
Ordinary shares, nominal value $ 0.0001 $ 0.0001
Ordinary shares, shares authorized600,000,000 600,000,000
Ordinary shares, shares issued225,027,621 221,721,674
Ordinary shares, shares outstanding224,643,255 221,337,308
Treasury stock, ordinary shares384,366 384,366

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Income Statement [Abstract]
Net sales $ 342,406 $ 355,909
Cost of goods sold100,368 97,416
Gross profit242,038 258,493
OPERATING EXPENSES:
Research and development57,693 27,209
Selling, general and administrative331,992 247,775
Impairment of long-lived assets12,371
Total operating expenses402,056 274,984
Operating loss(160,018)(16,491)
OTHER EXPENSE, NET:
Interest expense, net(13,460)(17,344)
Foreign exchange (loss) gain(848)776
Other income, net3,224 442
Total other expense, net(11,084)(16,126)
Loss before benefit for income taxes(171,102)(32,617)
Benefit for income taxes(47,751)(19,026)
Net loss $ (123,351) $ (13,591)
Net loss per ordinary share—basic and diluted $ (0.55) $ (0.07)
Weighted average ordinary shares outstanding—basic and diluted223,920,768 190,072,112
OTHER COMPREHENSIVE LOSS, NET OF TAX
Foreign currency translation adjustments $ (821) $ (325)
Pension remeasurements(287)
Other comprehensive loss(1,108)(325)
Comprehensive loss $ (124,459) $ (13,916)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in ThousandsTotalOrdinary Shares [Member]Treasury Stock [Member]Additional Paid-in Capital [Member]Accumulated Other Comprehensive Loss [Member]Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2019 $ 2,185,449 $ 19 $ (4,585) $ 2,797,602 $ (1,905) $ (605,682)
Beginning balance, shares at Dec. 31, 2019188,402,040 384,366
Issuance of ordinary shares in conjunction with vesting of restricted stock units and stock option exercises7,049 7,049
Issuance of ordinary shares in conjunction with vesting of restricted stock units and stock option exercises, shares2,560,573
Ordinary shares withheld for payment of employees’ withholding tax liability(46,664)(46,664)
Share-based compensation56,421 56,421
Currency translation adjustment(325)(325)
Net loss(13,591)(13,591)
Ending balance at Mar. 31, 20202,188,339 $ 19 $ (4,585)2,814,408 (2,230)(619,273)
Ending balance, shares at Mar. 31, 2020190,962,613 384,366
Beginning balance at Dec. 31, 20204,025,351 $ 22 $ (4,585)4,245,945 (145)(215,886)
Beginning balance, shares at Dec. 31, 2020221,721,674 384,366
Issuance of ordinary shares in conjunction with the exercise of stock options and the vesting of restricted stock and performance stock units19,843 19,843
Issuance of ordinary shares in conjunction with warrant exercises, shares3,305,947
Ordinary shares withheld for payment of employees’ withholding tax liability(128,261)(128,261)
Share-based compensation62,296 62,296
Currency translation adjustment(821)(821)
Pension remeasurements(287)(287)
Net loss(123,351)(123,351)
Ending balance at Mar. 31, 2021 $ 3,854,770 $ 22 $ (4,585) $ 4,199,823 $ (1,253) $ (339,237)
Ending balance, shares at Mar. 31, 2021225,027,621 384,366

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss $ (123,351) $ (13,591)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense70,820 65,741
Equity-settled share-based compensation61,166 56,421
Impairment of long-lived assets12,371
Amortization of debt discount and deferred financing costs773 5,569
Deferred income taxes(28,771)(2,082)
Foreign exchange and other adjustments(5,440)(190)
Changes in operating assets and liabilities:
Accounts receivable224,575 (16,869)
Inventories(13,660)(14,444)
Prepaid expenses and other current assets(65,575)(24,953)
Accounts payable993 28,551
Accrued trade discounts and rebates(28,736)(129,940)
Accrued expenses(111,963)(28,087)
Other non-current assets and liabilities3,070 11,281
Net cash used in operating activities(3,728)(62,593)
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments for acquisition, net of cash acquired(2,707,358)(105,200)
Purchases of property and equipment(18,333)(119,004)
Payments for long-term investments, net(3,808)
Change in escrow deposit for property purchase6,000
Net cash used in investing activities(2,729,499)(218,204)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from term loans1,577,612
Proceeds from the issuance of ordinary shares in connection with stock option exercises19,843 7,050
Payment of employee withholding taxes relating to share-based awards(128,261)(46,664)
Net cash provided by (used in) financing activities1,469,194 (39,614)
Effect of foreign exchange rate changes on cash, cash equivalents and restricted cash(3,998)(1,366)
Net decrease in cash, cash equivalents and restricted cash(1,268,031)(321,777)
Cash, cash equivalents and restricted cash, beginning of the period2,083,479 1,080,039
Cash, cash equivalents and restricted cash, end of the period815,448 758,262
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest18,988 26,636
Cash paid for income taxes, net of refunds received1,201 266
Cash paid for amounts included in the measurement of lease liabilities2,084 1,812
SUPPLEMENTAL NON-CASH FLOW INFORMATION:
Milestone payments for TEPEZZA intangible asset included in accrued expenses as of March 31, 2021 and March 31, 2020, respectively69,962
Purchases of property and equipment included in accounts payable and accrued expenses as of March 31, 2021 and March 31, 2020, respectively $ 10,523 $ 539

Basis of Presentation and Busin

Basis of Presentation and Business Overview3 Months Ended
Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation and Business OverviewNOTE 1 – BASIS OF PRESENTATION AND BUSINESS OVERVIEW Basis of Presentation Unless otherwise indicated or the context otherwise requires, references to “Horizon”, the “Company”, “we”, “us” and “our” refer to Horizon Therapeutics plc and its consolidated subsidiaries. On March 15, 2021, the Company completed its acquisition of Viela Bio, Inc. (“Viela”) and acquired all of the issued and outstanding shares of Viela’s common stock for $53.00 per share. The total consideration for the acquisition was approximately $3.0 billion, including cash acquired of $342.3 million. Following the completion of the acquisition, Viela became a wholly-owned subsidiary of the Company. The unaudited condensed consolidated financial statements presented herein include the results of operations of the acquired business from the date of acquisition. The unaudited condensed consolidated financial statements presented herein have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, the financial statements do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all adjustments, including normal recurring adjustments, considered necessary for a fair statement of the financial statements have been included. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. The December 31, 2020 condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP. Business Overview Horizon is focused on researching, developing and commercializing medicines that address critical needs for people impacted by rare, autoimmune and serious inflammatory diseases. The Company’s pipeline is purposeful: it applies scientific expertise and courage to bring clinically meaningful therapies to patients. Horizon believes science and compassion must work together to transform lives. The Company has two reportable segments, the orphan segment and the inflammation segment, and its portfolio is currently composed of 12 medicines in the areas of rare diseases, gout, ophthalmology and inflammation. The Viela acquisition expanded the Company’s marketed medicine portfolio by adding an additional rare disease medicine, UPLIZNA ® As of March 31, 2021, the Company’s marketed medicines consisted of the following:
Orphan
TEPEZZA ®
KRYSTEXXA ®
RAVICTI ®
PROCYSBI ®
ACTIMMUNE ®
BUPHENYL ®
QUINSAIR™ (levofloxacin) solution for inhalation
UPLIZNA (inebilizumab-cdon) injection, for intravenous use
Inflammation
PENNSAID ®
DUEXIS ®
RAYOS ®
VIMOVO ®

Summary of Significant Accounti

Summary of Significant Accounting Policies3 Months Ended
Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting PoliciesNOTE 2 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Recent Accounting Pronouncements From time to time, the Company adopts new accounting pronouncements issued by the Financial Accounting Standards Board (“FASB”) or other standard-setting bodies. In December 2019, the FASB issued Accounting Standards Update No. 2019-12, Income Taxes (Topic 740): Simplification and reduce the cost of accounting for income taxes Other recent authoritative guidance issued by the FASB (including technical corrections to the Accounting Standards Codification (“ASC”)), the American Institute of Certified Public Accountants and the Securities and Exchange Commission (“SEC”) did not, or are not expected to, have a material impact on the Company’s condensed consolidated financial statements and related disclosures. Significant Accounting Policies The Company’s significant accounting policies have not changed from those previously described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. The following accounting policy relating to intangible assets is disclosed in connection with the Viela acquisition. Intangible Assets Indefinite-lived intangible assets consist of capitalized in-process research and development (“IPR&D”). IPR&D assets represent capitalized incomplete research projects that the Company acquired through business combinations. Such assets are initially measured at their acquisition date fair values and are tested for impairment, until completion or abandonment of research and development efforts associated with the projects. An IPR&D asset is considered abandoned when research and development efforts associated with the asset have ceased, and there are no plans to sell or license the asset or derive value from the asset. At that point, the asset is considered to be impaired and is written off. Upon successful completion of each project, the Company will make a determination about the then remaining useful life of the intangible asset and begin amortization. The Company tests its indefinite-lived intangibles, including IPR&D assets, for impairment annually during the fourth quarter and more frequently if events or changes in circumstances indicate that it is more likely than not that the asset is impaired.

Net Loss per Share

Net Loss per Share3 Months Ended
Mar. 31, 2021
Earnings Per Share [Abstract]
Net Loss per ShareNOTE 3 – NET LOSS PER SHARE The following table presents basic and diluted net loss per share for the three months ended March 31, 2021 and 2020 (in thousands, except share and per share data):
For the Three Months Ended March 31,
2021
2020
Basic and diluted net loss per share calculation:
Numerator - net loss
$
(123,351
)
$
(13,591
)
Denominator - weighted average of ordinary shares outstanding
223,920,768
190,072,112
Basic and diluted net loss per share
$
(0.55
)
$
(0.07
)
Basic net loss per share is computed by dividing net loss by the weighted-average number of ordinary shares outstanding during the period. Diluted net loss per share reflects the potential dilution that could occur if securities or other contracts to issue ordinary shares were exercised, converted into ordinary shares or resulted in the issuance of ordinary shares that would have shared in the Company’s earnings. The computation of diluted net loss per share for the three months ended March 31, 2021 excluded 13.4 million shares subject to equity awards because their inclusion would have had an anti-dilutive effect on diluted net loss per share. The computation of diluted net loss per share for the three months ended March 31, 2020 excluded 9.3 million shares subject to equity awards and 14.0 million shares (based on the if-converted method) related to the Company’s 2.50% Exchangeable Senior Notes due 2022 (the “Exchangeable Senior Notes”) because their inclusion would have had an anti-dilutive effect on diluted net loss per share. On August 3, 2020, the Exchangeable Senior Notes were fully extinguished through exchanges for ordinary shares or cash redemption.

Acquisitions, Divestitures and

Acquisitions, Divestitures and Other Arrangements3 Months Ended
Mar. 31, 2021
Business Combinations [Abstract]
Acquisitions, Divestitures and Other ArrangementsNOTE 4 – ACQUISITIONS, DIVESTITURES AND OTHER ARRANGEMENTS Acquisition of Viela On March 15, 2021, the Company completed its acquisition of Viela and acquired all of the issued and outstanding shares of Viela’s common stock for $53.00 per share. The acquisition added an additional rare disease medicine, UPLIZNA, to the Company’s medicine portfolio. The Viela acquisition provides multiple opportunities to drive long-term growth and solidify the Company’s future as an innovation-driven biotech company. Viela’s mid-stage biologics pipeline, research and development (“R&D”) team and on-market medicine UPLIZNA, make it a complementary strategic fit with the Company’s pipeline, commercial portfolio and therapeutic areas of focus. Following completion of the acquisition, Viela became a wholly-owned subsidiary of the Company. The Company financed the transaction through cash on hand and $1.6 billion of aggregate principal amount of term loans pursuant to Company’s existing credit agreement, as described in Note 13. The total consideration for the acquisition was approximately $3.0 billion, including cash acquired of $342.3 million, and was composed of the following (in thousands):
E quity value (54,988,820 shares at $53.00 per share
$
2,914,407
Net settlements on the exercise of stock options
78,554
Consideration for exchange of Viela stock options
1,130
Total consideration
$
2,994,091
During the three months ended March 31, 2021, the Company incurred $28.0 million in Viela transaction costs, including advisory, legal, accounting, valuation and other Pursuant to ASC 805, Business Combinations (“ASC 805”), the Company accounted for the Viela acquisition as a business combination using the acquisition method of accounting. Identifiable assets and liabilities of Viela, including identifiable intangible assets, were recorded based on their estimated fair values as of the date of the closing of the acquisition. The excess of the purchase price over the fair value of the net assets acquired was recorded as goodwill. The valuation of assets acquired and liabilities assumed has not yet been finalized as of March 31, 2021. While all amounts remain subject to adjustments, the areas subject to the most significant potential adjustments are inventory, intangible assets, IPR&D and deferred income taxes. As a result, the Company recorded preliminary estimates for the fair value of assets acquired and liabilities assumed as of the acquisition date. Such preliminary valuation required estimates and assumptions including, but not limited to, estimating future cash flows and direct costs in addition to developing the appropriate discount rates and current market profit margins. Accordingly, the purchase price adjustments are preliminary and are subject to further adjustments as additional information becomes available and as additional analyses are performed, and such further adjustments may be material. The Company’s management believes the fair values recognized for the assets acquired and the liabilities assumed are based on reasonable estimates and assumptions. The following table summarizes the preliminary fair values assigned to the assets acquired and the liabilities assumed by the Company along with the resulting goodwill (in thousands):
Allocation
Deferred tax liabilities, net
$
(457,928
)
Accrued expenses
(73,401
)
Other long-term liabilities
(22,631
)
Accounts payable
(4,768
)
Accrued trade discounts and rebates
(1,492
)
Marketable securities
400
Property, plant and equipment
1,747
Other assets
3,253
Accounts receivable
8,053
Prepaid expenses and other current assets
16,444
Inventories
149,348
Cash and cash equivalents
342,347
In-process research and development
910,000
Developed technology
1,460,000
(Liabilities assumed) and assets acquired
2,331,372
Goodwill
662,719
Fair value of consideration paid
$
2,994,091
Inventories acquired included raw materials, work in process and finished goods for UPLIZNA. Inventories were recorded at their preliminary estimated fair values. The fair value of finished goods has been determined based on the estimated selling price, net of selling costs and a margin on the selling activities. The fair value of work in process has been determined based on estimated selling price, net of selling costs and costs to complete the manufacturing, and a margin on the selling and manufacturing activities. The fair value of raw materials was estimated to equal the replacement cost. A step-up in the value of inventory of $149.3 million was recorded in connection with the acquisition, which was composed of $10.1 million for raw materials, $119.0 million for work-in-process and $20.2 million for finished goods. During the three months ended March 31, 2021, the Company recorded inventory step-up expense of $0.9 million related to UPLIZNA based on the acquired units sold during the period. Other tangible assets and liabilities were valued at their respective carrying amounts as management believes that these amounts approximated their acquisition-date fair values. Developed technology is an intangible asset that reflects the estimated fair value of Viela’s rights to its currently marketed medicine, UPLIZNA. The preliminary estimated fair values of the developed technology represent preliminary valuations performed with the assistance of an independent appraisal firm based on management’s estimates, forecasted financial information and reasonable and supportable assumptions. The preliminary fair value of developed technology was determined using an income approach. The income approach explicitly recognizes that the fair value of an asset is premised upon the expected receipt of future economic benefits such as earnings and cash inflows based on current sales projections and estimated direct costs for UPLIZNA. Indications of value were developed by discounting these benefits to their acquisition-date fair value at a discount rate of 11.5% that reflects the return requirements of the market. Some of the most significant assumptions inherent in the development of the asset valuation include the estimated net cash flows for each year (including net sales, cost of goods sold, sales and marketing costs and R&D costs) and the discount rate. The fair value of the UPLIZNA developed technology was capitalized as of the Viela acquisition date and is subsequently being amortized over approximately 14 years. IPR&D is related to R&D projects including:
(i)
Potential regulatory approval of UPLIZNA for neuromyelitis optica spectrum disorder outside of the United States and certain other indications worldwide. As of the date of the acquisition, UPLIZNA had not been granted regulatory approval in any territory outside the United States. On March 24, 2021, the Company announced that its strategic partner Mitsubishi Tanabe Pharma Corporation, had received manufacturing and marketing approval for UPLIZNA in Japan. Refer to Note 8 for further details.
(ii)
HZN-7734, an investigational human monoclonal antibody designed to deplete plasmacytoid dendritic cells (pDCs), a cell type believed to be critical to the pathogenesis of multiple autoimmune diseases.
(iii)
HZN-4920, an investigational fusion protein designed to block a key co-stimulatory pathway involved in many autoimmune and inflammatory diseases. Each IPR&D asset is considered separable from the business as each project could be sold to a third party. The fair value of each IPR&D asset was determined using an income approach. The income approach explicitly recognizes that the fair value of an asset is premised upon the expected receipt of future economic benefits such as earnings and cash inflows based on sales projections and estimated direct costs. Indications of value are developed by discounting these benefits to their present value at a discount rate of 12.5% that reflects the return requirements of the market. Some of the most significant assumptions inherent in the development of the asset valuations include the estimated net cash flows for each year (including net sales, cost of goods sold, sales and marketing costs and R&D costs), the discount rate, the assessment of each asset’s life cycle and the potential regulatory and commercial success risk. The fair value of the various IPR&D assets was recorded as an indefinite-lived intangible asset and will be tested for impairment until completion or abandonment of R&D efforts associated with the project. The Company reviews amounts capitalized as acquired IPR&D for impairment annually and whenever events or changes in circumstances indicate that the carrying value of the assets might not be recoverable. Deferred tax assets and liabilities arise from acquisition accounting adjustments where book values of certain assets and liabilities differ from their tax bases. Deferred tax assets and liabilities are recorded at the currently enacted rates which will be in effect at the time when the temporary differences are expected to reverse in the country where the underlying assets and liabilities are located. The developed technology, IPR&D assets and inventory acquired through the Viela acquisition were located in the United States, as of the acquisition date, where a U.S. tax rate of 24.1% is being utilized and a significant deferred tax liability of $457.9 million was recorded. Goodwill represents the excess of the total consideration over the estimated fair value of net assets acquired and was recorded in the consolidated balance sheet as of the acquisition date. The goodwill was primarily attributable to the establishment of a deferred tax liability for the developed technology intangible asset and the IPR&D intangible assets. Viela’s mid-stage biologics pipeline, R&D team and on-market medicine UPLIZNA, make it a complementary strategic fit with the Company’s pipeline, commercial portfolio and therapeutic areas of focus. The Company does not expect any portion of this goodwill to be deductible for tax purposes. The following table presents the pro forma combined results of the Company and Viela for the three months ended March 31, 2021 and 2020 as if the acquisition of Viela had occurred on January 1, 2020:
For the Three Months Ended March 31,
2021
2020
As reported
Pro forma adjustments
Pro forma
As reported
Pro forma adjustments
Pro forma
Net sales
$
342,406
$
10,588
$
352,994
$
355,909
$

$
355,909
Net loss
(123,351
)
(43,556
)
(166,907
)
(13,591
)
(120,002
)
(133,593
) The pro forma combined financial information was prepared using the acquisition method of accounting and was based on the historical financial information of Horizon and Viela. In order to reflect the pro forma information as if the acquisition occurred on January 1, 2020 as required, the pro forma financial information includes adjustments to reflect incremental amortization expense to be incurred based on the current preliminary fair values of the identifiable intangible assets acquired; the incremental cost of products sold related to the fair value adjustments associated with acquisition date inventory; the additional interest expense associated with the issuance of debt to finance the acquisition; and the reclassification of transaction costs incurred during the three months ended March 31, 2021 to the three months ended March 31, 2020. Significant non-recurring pro forma adjustments include transaction costs of $86.1 million which were assumed to have been incurred on January 1, 2020 and were recognized as if incurred in the first quarter of 2020. The pro forma financial information is not necessarily indicative of what the consolidated results of operations would have been had the acquisition actually been completed on January 1, 2020. In addition, the pro forma financial information is not a projection of future results of operations of the combined company nor does it reflect the expected realization of any synergies or cost savings associated with the acquisition. Acquisition of Curzion Pharmaceuticals, Inc. On April 1, 2020, the Company acquired Curzion Pharmaceuticals, Inc. (“Curzion”), a privately held development-stage biopharma company, and its development-stage oral selective lysophosphatidic acid 1 receptor (LPAR 1 Under the terms of the acquisition agreement, the Company acquired Curzion for a $45.0 million upfront payment with additional payments contingent on the achievement of development and regulatory milestones. Pursuant to ASC 805, the Company accounted for the Curzion acquisition as the purchase of an i n-process research and development Research and Development , Refer to Note 15 for further detail on HZN-825 milestone payments. Sale of RAVICTI and BUPHENYL Rights in Japan On October 27, 2020, the Company sold its rights to develop and commercialize RAVICTI and BUPHENYL in Japan to Medical Need Europe AB, part of the Immedica Group, Acquisition of River Vision On May 8, 2017, the Company acquired 100% of the equity interests in River Vision Development Corp. (“River Vision”) for upfront cash payments totaling approximately $150.3 million, including cash acquired of $6.3 million, with additional potential future milestone and royalty payments contingent on the satisfaction of certain regulatory milestones and sales thresholds. Under the acquisition agreement for River Vision, the Company agreed to pay up to $325.0 million upon the attainment of various milestones, composed of $100.0 million related to U.S. Food and Drug Administration (“FDA”) approval and $225.0 million related to net sales thresholds for TEPEZZA. The agreement also includes a royalty payment of 3 percent of the portion of annual worldwide net sales exceeding $300.0 million (if any). The Company made the milestone payment of $100.0 million related to FDA approval during the first quarter of 2020 which is now capitalized as a finite-lived intangible asset representing the developed technology for TEPEZZA. Additionally, under the Company’s license agreement with F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc. (together referred to as “Roche”), the Company made a milestone payment of CHF5.0 million ($5.2 million when converted using a CHF-to-Dollar exchange rate at the date of payment of 1.0382), during the first quarter of 2020 which the Company also capitalized as a finite-lived intangible asset representing the developed technology for TEPEZZA. In April 2020, a subsidiary of the Company entered into an agreement with S.R. One, Limited (“S.R. One”) and an agreement with Lundbeckfond Invest A/S (“Lundbeckfond”) p In addition, during the year ended December 31, 2020, the Company recorded $120.8 million as a finite-lived intangible asset representing the developed technology for TEPEZZA, composed of $67.0 million in relation to the expected future attainment of various net sales milestones payable under the acquisition agreement for River Vision and CHF50.0 million ($53.8 million when converted using a CHF-to-Dollar exchange rate as of the date the intangible asset was recorded) in relation to the expected future attainment of various net sales milestones payable to Roche. The liabilities relating to these net sales milestones were recorded in accrued expenses on the consolidated balance sheet as of December 31, 2020. The Company paid the milestones to Roche in February 2021 and paid the applicable milestones to the former River Vision stockholders in April 2021. There are no further TEPEZZA net sales milestone obligations remaining to Roche and the former River Vision stockholders. Licensing Agreement On November 21, 2020, the Company entered into a global collaboration and license agreement with Halozyme Therapeutics, Inc. (“Halozyme”) that gives the Company exclusive access to Halozyme’s ENHANZE ® Other Arrangements On January 3, 2019, the Company entered into a collaboration agreement with HemoShear Therapeutics, LLC (“HemoShear”), a biotechnology company, to discover novel therapeutic targets for gout. The collaboration provides the Company with an opportunity to address unmet treatment needs for people with gout by evaluating new targets for the control of serum uric acid levels. Under the terms of the agreement, the Company paid HemoShear an upfront cash payment of $2.0 million with additional potential future milestone payments upon commencement of new stages of development, contingent on the Company’s approval at each stage. In June 2019, the Company incurred a $4.0 million progress payment, which was subsequently paid in July 2019. In June 2020, a $3.0 million progress payment became due, which the Company subsequently paid in July 2020. In February 2021, a $3.0 million progress payment became due and was paid during the first quarter of 2021.

Inventories

Inventories3 Months Ended
Mar. 31, 2021
Inventory Disclosure [Abstract]
InventoriesNOTE 5 – INVENTORIES Inventories are stated at the lower of cost or net realizable value. Inventories consist of raw materials, work-in-process and finished goods. The Company has entered into manufacturing and supply agreements for the manufacture of drug substance and finished goods inventories, and the purchase of raw materials and production supplies. The Company’s inventories include the direct purchase cost of materials and supplies and manufacturing overhead costs. The components of inventories as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Raw materials
$
29,861
$
11,760
Work-in-process
140,813
33,167
Finished goods
67,632
30,356
Inventories, net
$
238,306
$
75,283
Raw materials, work-in-process, and finished goods at March 31, 2021 included $10.1 million, $119.0 million, and $19.3 million, respectively, of stepped-up UPLIZNA inventory. The Company recorded $0.9 million of UPLIZNA inventory step-up expense during the three months ended March 31, 2021. Because inventory step-up expense is related to an acquisition, will not continue indefinitely and has a significant effect on the Company’s gross profit, gross margin percentage and net loss for all affected periods, the Company discloses balance sheet and income statement amounts related to inventory step-up within the notes to the condensed consolidated financial statements.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets3 Months Ended
Mar. 31, 2021
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current AssetsNOTE 6 – PREPAID EXPENSES AND OTHER CURRENT ASSETS Prepaid expenses and other current assets as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Advance payments for inventory
$
167,753
$
137,680
Deferred charge for taxes on intercompany profit
58,617
52,306
Prepaid income taxes and income tax receivable
23,456
102
Rabbi trust assets
21,709
18,423
Other prepaid expenses and other current assets
62,907
43,434
Prepaid expenses and other current assets
$
334,442
$
251,945
Advance payments for inventory as of March 31, 2021 and December 31, 2020, primarily represented payments made to the contract manufacturer of TEPEZZA drug substance.

Property and Equipment

Property and Equipment3 Months Ended
Mar. 31, 2021
Property Plant And Equipment [Abstract]
Property and EquipmentNOTE 7 – PROPERTY AND EQUIPMENT Property and equipment as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Buildings
$
128,268
$
80,341
Land and land improvements
38,880
38,076
Machinery and equipment
16,910
4,695
Software
14,487
14,618
Furniture and fixtures
12,017
5,973
Leasehold improvements
9,558
26,323
Construction in process
7,370
63,656
Other
4,917
3,146
232,407
236,828
Less accumulated depreciation
(30,550
)
(47,791
)
Property and equipment, net
$
201,857
$
189,037
Depreciation expense was $4.5 million and $7.2 million for the three months ended March 31, 2021 and 2020, respectively. In February 2020, the Company purchased a three -building campus in Deerfield, Illinois for total consideration and directly attributable transaction costs of $ million. The Deerfield campus totals 70 acres and consists of approximately 650,000 square feet of office space. In February 2021, the Company’s Lake Forest office employees moved to the Deerfield campus and the Company is marketing its Lake Forest office space for sublease . The increase in amount classified as buildings and the decrease in amount classified as construction in process is primarily due to the Deerfield campus becoming operational in February 2021. The decreases in leasehold improvements and accumulated depreciation amounts are primarily due to the Company vacating the Lake Forest office building in February 2021.

Goodwill and Intangible Assets

Goodwill and Intangible Assets3 Months Ended
Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible AssetsNOTE 8 – GOODWILL AND INTANGIBLE ASSETS Goodwill The gross carrying amount of goodwill as of March 31, 2021 and December 31, 2020 was $1,076.4 million and $413.7 million, respectively. The table below presents goodwill for the Company’s reportable segments as of March 31, 2021 (in thousands):
Orphan
Inflammation
Total
Balance at December 31, 2020
$
357,498
$
56,171
$
413,669
Acquired during the period
662,719

662,719
Balance at March 31, 2021
$
1,020,217
$
56,171
$
1,076,388
In March 2021, the Company recognized goodwill with a preliminary value of $662.7 million in connection with the Viela acquisition, which represented the excess of the purchase price over the fair value of the net assets acquired. See Note 4 for further details. As of March 31, 2021, there were no accumulated goodwill impairment losses. Intangible Assets As of March 31, 2021, the Company’s finite-lived intangible assets consisted of developed technology related to ACTIMMUNE, BUPHENYL, KRYSTEXXA, PROCYSBI, RAVICTI, RAYOS, TEPEZZA and UPLIZNA as well as customer relationships for ACTIMMUNE. The intangible assets related to PENNSAID 2%, and VIMOVO developed technology were fully amortized as of December 31, 2020. On March 15, 2021, in connection with the acquisition of Viela, the Company capitalized $1,460.0 million of developed technology related to UPLIZNA. See Note 4 for further details. In connection with the acquisition of River Vision, the Company capitalized payments of $336.0 million related to TEPEZZA developed technology during the year ended December 31, 2020. See Note 4 for further details on the River Vision acquisition. Intangible assets as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Cost
Accumulated Amortization
Net Book Value
Cost Basis
Accumulated Amortization
Net Book Value
Developed technology
$
4,587,515
$
(1,380,104
)
$
3,207,411
$
3,093,886
$
(1,313,934
)
$
1,779,952
In-process research and development (1)
880,000

880,000



Customer relationships
8,100
(5,290
)
2,810
8,100
(5,090
)
3,010
Total intangible assets
$
5,475,615
$
(1,385,394
)
$
4,090,221
$
3,101,986
$
(1,319,024
)
$
1,782,962
(1)
The Company acquired IPR&D of $910.0 million relating to Viela. On March 24, 2021, the Company announced that its strategic partner, Mitsubishi Tanabe Pharma Corporation, had received manufacturing and marketing approval of UPLIZNA in Japan. As a result, the Company transferred $30.0 million of IPR&D to developed technology. As of March 31, 2021, the remaining IPR&D relating to the Viela acquisition was $880.0 million. Amortization expense for the three months ended March 31, 2021 and 2020 was $66.4 million and $58.6 million, respectively. IPR&D is not amortized until successful completion of a project. As of March 31, 2021, estimated future amortization expense was as follows (in thousands):
2021 (April to December)
$
268,242
2022
355,047
2023
354,582
2024
353,102
2025
350,861
Thereafter
1,528,387
Total
$
3,210,221

Accrued Expenses

Accrued Expenses3 Months Ended
Mar. 31, 2021
Payables And Accruals [Abstract]
Accrued Liabilities / ExpensesNOTE 9 – ACCRUED EXPENSES Accrued expenses as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Payroll-related expenses
$
72,906
$
121,577
Accrued milestone payments
69,962
123,442
Consulting and professional services
50,635
21,893
Allowances for returns
38,089
40,918
R&D and manufacturing programs
31,376
17,289
Accrued royalties
23,839
68,006
Advertising and marketing
17,468
12,428
Pricing review liability
17,169
16,046
Accrued interest
7,784
14,207
Accrued other
60,398
49,761
Accrued expenses
$
389,626
$
485,567
As of March 31, 2021, accrued milestone payments represented the attainment in 2020 of a TEPEZZA net sales milestone payable under the acquisition agreement for River Vision. The Company paid the milestone to the former River Vision stockholders in April 2021. Refer to Note 4 for further detail.

Accrued Trade Discounts and Reb

Accrued Trade Discounts and Rebates3 Months Ended
Mar. 31, 2021
Valuation And Qualifying Accounts Disclosure [Line Items]
Accrued Liabilities / ExpensesNOTE 9 – ACCRUED EXPENSES Accrued expenses as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Payroll-related expenses
$
72,906
$
121,577
Accrued milestone payments
69,962
123,442
Consulting and professional services
50,635
21,893
Allowances for returns
38,089
40,918
R&D and manufacturing programs
31,376
17,289
Accrued royalties
23,839
68,006
Advertising and marketing
17,468
12,428
Pricing review liability
17,169
16,046
Accrued interest
7,784
14,207
Accrued other
60,398
49,761
Accrued expenses
$
389,626
$
485,567
As of March 31, 2021, accrued milestone payments represented the attainment in 2020 of a TEPEZZA net sales milestone payable under the acquisition agreement for River Vision. The Company paid the milestone to the former River Vision stockholders in April 2021. Refer to Note 4 for further detail.
Accrued Trade Discounts and Rebates [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Accrued Liabilities / ExpensesNOTE 10 – ACCRUED TRADE DISCOUNTS AND REBATES Accrued trade discounts and rebates as of , 2020 (in thousands):
March 31, 2021
December 31, 2020
Accrued government rebates and chargebacks
$
177,758
$
172,893
Accrued co-pay and other patient assistance
80,449
96,924
Accrued commercial rebates and wholesaler fees
67,025
82,646
Accrued trade discounts and rebates
$
325,232
$
352,463
Invoiced commercial rebates and wholesaler fees, co-pay and other patient assistance costs, and government rebates and chargebacks in accounts payable
2,608
1,452
Total customer-related accruals and allowances
$
327,840
$
353,915
The following table summarizes changes in the Company’s customer-related accruals and allowances from December 31, 2020 to March 31, 2021 (in thousands):
Government
Co-Pay and
Wholesaler Fees
Rebates and
Other Patient
and Commercial
Chargebacks
Assistance
Rebates
Total
Balance at December 31, 2020
$
172,893
$
96,924
$
84,098
$
353,915
Current provisions relating to sales during the three months ended March 31, 2021
146,491
199,031
63,971
409,493
Adjustments relating to prior-year sales
(3,716
)
(52
)
(758
)
(4,526
)
Payments relating to sales during the three months ended March 31, 2021
(31,764
)
(124,234
)
(10,799
)
(166,797
)
Payments relating to prior-year sales
(107,557
)
(90,728
)
(67,452
)
(265,737
)
Viela acquisition on March 15, 2021
1,411
11
70
1,492
Balance at March 31, 2021
$
177,758
$
80,952
$
69,130
$
327,840

Segment and Other Information

Segment and Other Information3 Months Ended
Mar. 31, 2021
Segment Reporting [Abstract]
Segment and Other InformationNOTE 11 The Company has two reportable segments, the orphan segment and the inflammation segment, and the Company reports net sales and segment operating income for each segment. On March 15, 2021, the Company completed its acquisition of Viela. The acquisition expanded the Company’s medicine portfolio by adding an additional rare disease medicine, UPLIZNA. The orphan segment includes the medicines TEPEZZA, KRYSTEXXA, RAVICTI, PROCYSBI, ACTIMMUNE, BUPHENYL, QUINSAIR, UPLIZNA and also the Company’s R&D programs. The inflammation segment includes the medicines PENNSAID 2%, DUEXIS, RAYOS and VIMOVO. The Company’s chief operating decision maker (“CODM”) evaluates the financial performance of the Company’s segments based upon segment operating income. Segment operating income is defined as loss before benefit for income taxes adjusted for the items set forth in the reconciliation below. Items below income from operations are not reported by segment, since they are excluded from the measure of segment profitability reviewed by the Company’s CODM. Additionally, certain expenses are not allocated to a segment. The Company does not report balance sheet information by segment as no balance sheet by segment is reviewed by the Company’s CODM. The following table reflects net sales by medicine for the Company’s reportable segments for the three months ended March 31, 2021 and 2020 (in thousands):
Three Months Ended March 31
2021
2020
KRYSTEXXA
$
106,757
$
93,248
RAVICTI
72,817
61,189
PROCYSBI
43,363
38,343
ACTIMMUNE
28,763
26,541
TEPEZZA
2,065
23,452
UPLIZNA
1,873

BUPHENYL
1,660
2,313
QUINSAIR
209
277
Orphan segment net sales
$
257,507
$
245,363
PENNSAID 2%
45,817
41,563
DUEXIS
19,465
31,346
RAYOS
15,272
18,209
VIMOVO
4,345
19,428
Inflammation segment net sales
$
84,899
$
110,546
Total net sales
$
342,406
$
355,909
The table below provides reconciliations of the Company’s segment operating income to the Company’s total loss before benefit for income taxes for the three months ended March 31, 2021 and 2020 (in thousands):
For the Three Months Ended March 31,
2021
2020
Segment operating income:
Orphan
$
1,054
$
54,356
Inflammation
42,680
51,942
Reconciling items:
Amortization and step-up:
Intangible amortization expense
(66,369
)
(58,575
)
Inventory step-up expense
(911
)

Share-based compensation
(61,166
)
(56,421
)
Acquisition/divestiture-related costs
(49,391
)
(284
)
Interest expense, net
(13,460
)
(17,344
)
Impairment of long-lived assets
(12,371
)

Depreciation
(4,451
)
(7,165
)
Restructuring and realignment costs
(6,093
)

Upfront, progress and milestone payments related to license and collaboration agreements
(3,000
)

Foreign exchange (loss) gain
(848
)
776
Drug substance harmonization costs

(290
)
Fees related to refinancing activities

(54
)
Other income, net
3,224
442
Loss before benefit for income taxes
$
(171,102
)
$
(32,617
)
The following table presents the amount and percentage of gross sales to customers that represented more than 10% of the Company’s gross sales included in its two reportable segments and all other customers as a group for the three months ended March 31, 2021 and 2020 (in thousands, except percentages):
For the Three Months Ended March 31,
2021
2020
Amount
% of
Amount
% of Gross
Sales
Sales
Customer A
$
248,740
33
%
$
246,775
31
%
Customer B
184,687
24
%
207,277
26
%
Customer C
118,037
15
%
133,876
17
%
Customer D
90,619
12
%
84,788
10
%
Other Customers
119,449
16
%
130,806
16
%
Gross Sales
$
761,532
100
%
$
803,522
100
% Geographic revenues are determined based on the country in which the Company’s customers are located. The following table presents a summary of net sales attributed to geographic sources for the three months ended March 31, 2021 and 2020 (in thousands, except percentages):
Three Months Ended March 31, 2021
Three Months Ended March 31, 2020
Amount
% of Total Net Sales
Amount
% of Total Net Sales
United States
$
340,330
99%
$
354,016
100%
Rest of world
2,076
1%
1,893
*
Net sales
$
342,406
$
355,909
*Less than 1%

Fair Value Measurements

Fair Value Measurements3 Months Ended
Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value MeasurementsNOTE 12 – FAIR VALUE MEASUREMENTS The following tables and paragraphs set forth the Company’s financial instruments that are measured at fair value on a recurring basis within the fair value hierarchy. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. The following describes three levels of inputs that may be used to measure fair value: Level 1 —Observable inputs such as quoted prices in active markets for identical assets or liabilities; Level 2 —Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and Level 3 —Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The Company utilizes the market approach to measure fair value for its money market funds. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities. Other current assets and other long-term liabilities recorded at fair value on a recurring basis are composed of investments held in a rabbi trust and the related deferred liability for deferred compensation arrangements. Quoted prices for this investment, primarily in mutual funds, are available in active markets. Thus, the Company’s investments related to deferred compensation arrangements and the related long-term liability are classified as Level 1 measurements in the fair value hierarchy. Assets and liabilities measured at fair value on a recurring basis The following tables set forth the Company’s financial assets and liabilities at fair value on a recurring basis as of March 31, 2021 and December 31, 2020 (in thousands):
March 31, 2021
Level 1
Level 2
Level 3
Total
Assets:
Money market funds
$
521,000
$

$

$
521,000
Other current assets
21,695


21,695
Total assets at fair value
$
542,695
$

$

$
542,695
Liabilities:
Other long-term liabilities
(21,695
)


(21,695
)
Total liabilities at fair value
$
(21,695
)
$

$

$
(21,695
)
December 31, 2020
Level 1
Level 2
Level 3
Total
Assets:
Money market funds
$
1,906,000


$
1,906,000
Other current assets
18,423


18,423
Total assets at fair value
$
1,924,423
$

$

$
1,924,423
Liabilities:
Other long-term liabilities
(18,423
)


(18,423
)
Total liabilities at fair value
$
(18,423
)
$

$

$
(18,423
)

Debt Agreements

Debt Agreements3 Months Ended
Mar. 31, 2021
Debt Disclosure [Abstract]
Debt AgreementsNOTE 13 – DEBT AGREEMENTS The Company’s outstanding debt balances as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Term Loan Facility due 2028
$
1,600,000

Term Loan Facility due 2026
418,026
418,026
Senior Notes due 2027
600,000
600,000
Total face value
2,618,026
1,018,026
Debt discount
(13,675
)
(10,061
)
Deferred financing fees
(25,834
)
(4,586
)
Total long-term debt
2,578,517
1,003,379
Less: current maturities
16,000

Long-term debt, net of current maturities
$
2,562,517
$
1,003,379
Term Loan Facility and Revolving Credit Facility On March 15, 2021, Horizon Therapeutics USA, Inc. (formerly known as Horizon Pharma USA, Inc.) (the “Borrower” or “HTUSA”), a wholly-owned subsidiary of the Company, borrowed approximately $1.6 billion aggregate principal amount of loans (the “Incremental Loans”) pursuant to an amendment (the “March 2021 Amendment”) to the credit agreement, dated as of May 7, 2015, by and among the Borrower, the Company and certain of its subsidiaries as guarantors, the lenders party thereto from time to time and Citibank, N.A., as administrative agent and collateral agent, as amended by Amendment No. 1, dated as of October 25, 2016, Amendment No. 2, dated March 29, 2017, Amendment No. 3, dated October 23, 2017, Amendment No. 4, dated October 19, 2018, Amendment No. 5, dated March 11, 2019, Amendment No. 6, dated May 22, 2019, Amendment No. 7, dated December 18, 2019 and the Incremental Amendment and Joinder Agreement, dated August 17, 2020 (the “Term Loan Facility”). Pursuant to Amendment No. 7, the Borrower borrowed approximately $418.0 million aggregate principal amount of loans (the “December 2019 Refinancing Loans”). Pursuant to Amendment No. 5, the Borrower received $200.0 million aggregate principal amount of revolving commitments, which was increased to $275.0 million aggregate amount of revolving commitments (the “Incremental Revolving Commitments”) pursuant to the Incremental Amendment and Joinder Agreement. The Incremental Revolving Commitments were established pursuant to an incremental facility (the “Revolving Credit Facility”) and includes a $50.0 million letter of credit sub-facility. The Incremental Revolving Commitments will terminate in March 2024. Borrowings under the Revolving Credit Facility are available for general corporate purposes. As of March 31, 2021, the Revolving Credit Facility was undrawn. As used herein, all references to the “Credit Agreement” are references to the original credit agreement, dated as of May 7, 2015, as amended through the March 2021 Amendment. The Incremental Loans were incurred as a separate class of term loans under the Credit Agreement with substantially the same terms of the December 2019 Refinancing Loans. The Borrower used the proceeds of the Incremental Loans to fund a portion of the consideration payable in the acquisition of Viela. The Incremental Loans bear interest at a rate, at Borrower’s option, equal to the London Inter-Bank Offered Rate (“LIBOR”), plus 2.00% per annum (subject to a 0.50% LIBOR floor) or the adjusted base rate plus 1.00% per annum, with a step-down to LIBOR plus 1.75% per annum or the adjusted base rate plus 0.75% per annum at the time the Company’s leverage ratio is less than or equal to 2.00 to 1.00. The adjusted base rate is defined as the greatest of (a) LIBOR (using one-month interest period) plus 1.00%, (b) the prime rate, (c) the federal funds rate plus 0.50%, and (d) 1.00%. The December 2019 Refinancing Loans were incurred as a separate new class of term loans under the Credit Agreement with substantially the same terms as the previously outstanding senior secured term loans incurred on May 22, 2019 (the “Refinanced Loans”) to effectuate a repricing of the Refinanced Loans. The Borrower used the proceeds of the December 2019 Refinancing Loans to repay the Refinanced Loans, which totaled approximately $418.0 million. The December 2019 Refinancing Loans bear interest at a rate, at the Borrower’s option, equal to LIBOR plus 2.25% per annum (subject to a 0.00% LIBOR floor) or the adjusted base rate plus 1.25% per annum, with a step-down to LIBOR plus 2.00% per annum or the adjusted base rate plus 1.00% per annum at the time the Company’s leverage ratio is less than or equal to 2.00 to 1.00. The loans under the Revolving Credit Facility bear interest, at the Borrower’s option, at a rate equal to either LIBOR plus an applicable margin of 2.25% per annum (subject to a LIBOR floor of 0.00%), or the adjusted base rate plus 1.25% per annum, with a step-down to LIBOR plus 2.00% per annum or the adjusted base rate plus 1.00% per annum at the time the Company’s leverage ratio is less than or equal to 2.00 to 1.00. The Credit Agreement provides for (i) the Incremental Loans, (ii) the December 2019 Refinancing Loans, (iii) the Revolving Credit Facility, (iv) one or more uncommitted additional incremental loan facilities subject to the satisfaction of certain financial and other conditions, and (v) one or more uncommitted refinancing loan facilities with respect to loans thereunder. The Credit Agreement allows for the Company and certain of its subsidiaries to become additional borrowers under incremental or refinancing facilities. The obligations under the Credit Agreement (including obligations in respect of the Incremental Loans, December 2019 Refinancing Loans and the Revolving Credit Facility) and any swap obligations and cash management obligations owing to a lender (or an affiliate of a lender) are guaranteed by the Company and each of the Company’s existing and subsequently acquired or formed direct and indirect subsidiaries (other than certain immaterial subsidiaries, subsidiaries whose guarantee would result in material adverse tax consequences and subsidiaries whose guarantee is prohibited by applicable law). The obligations under the Credit Agreement (including obligations in respect of the Incremental Loans, December 2019 Refinancing Loans and the Revolving Credit Facility) and any related swap and cash management obligations are secured, subject to customary permitted liens and other agreed upon exceptions, by a perfected security interest in (i) all tangible and intangible assets of the Borrower and the guarantors, except for certain customary excluded assets, and (ii) all of the capital stock owned by the Borrower and guarantors thereunder (limited, in the case of the stock of certain non-U.S. subsidiaries of the Borrower, to 65% of the capital stock of such subsidiaries). The Borrower and the guarantors under the Credit Agreement are individually and collectively referred to herein as a “Loan Party” and the “Loan Parties,” as applicable. The Borrower is permitted to make voluntary prepayments of the loans under the Credit Agreement at any time without payment of a premium , except that with respect to the Incremental Loans, a 1% premium will apply to a repayment of the Incremental Loans in connection with a repricing of, or any amendment to the Credit Agreement in a repricing of, such loans effected on or prior to September 15, 2021 The Incremental Loans will amortize in equal quarterly installments in an aggregate annual amount equal to 1% of the original principal amount thereof, with any remaining balance payable on March 15, 2028, the final maturity date of the Incremental Loans. December 2019 Refinancing Loans are due and The Credit Agreement contains customary representations and warranties and customary affirmative and negative covenants, including, among other things, restrictions on indebtedness, liens, investments, mergers, dispositions, prepayment of other indebtedness and dividends and other distributions. The Credit Agreement also contains a springing financial maintenance covenant, which requires that the Company maintain a specified leverage ratio at the end of each fiscal quarter. The covenant is tested if both the outstanding loans and letters of credit under the Revolving Credit Facility, subject to certain exceptions, exceed 25% of the total commitments under the Revolving Credit Facility as of the last day of any fiscal quarter. If the Company fails to meet this covenant, the commitments under the Revolving Credit Facility could be terminated and any outstanding borrowings, together with accrued interest, under the Revolving Credit Facility could be declared immediately due and payable. Other events of default under the Credit Agreement include: (i) the failure by the Borrower to timely make payments due under the Credit Agreement; (ii) material misrepresentations or misstatements in any representation or warranty by any Loan Party when made; (iii) failure by any Loan Party to comply with the covenants under the Credit Agreement and other related agreements; (iv) certain defaults under a specified amount of other indebtedness of the Company or its subsidiaries; (v) insolvency or bankruptcy-related events with respect to the Company or any of its material subsidiaries; (vi) certain undischarged judgments against the Company or any of its restricted subsidiaries; (vii) certain ERISA-related events reasonably expected to have a material adverse effect on the Company and its restricted subsidiaries taken as a whole; (viii) certain security interests or liens under the loan documents ceasing to be, or being asserted by the Company or its restricted subsidiaries not to be, in full force and effect; (ix) any loan document or material provision thereof ceasing to be, or any challenge or assertion by any Loan Party that such loan document or material provision is not, in full force and effect; and (x) the occurrence of a change of control. If one or more events of default occurs and continues beyond any applicable cure period, the administrative agent may, with the consent of the lenders holding a majority of the loans and commitments under the facilities, or will, at the request of such lenders, terminate the commitments of the lenders to make further loans and declare all of the obligations of the Loan Parties under the Credit Agreement to be immediately due and payable. The interest on the Incremental Loans is variable and, as of March 31, 2021 the interest rate on the Incremental Loans was 2.50% and the effective interest rate was 2.76%. The interest on the December 2019 Refinancing Loans is variable and as of March 31, 2021 the interest rate on the December 2019 Refinancing Loans was 2.13% and the effective interest rate was 2.42%. As of March 31, 2021, the fair value of the amounts outstanding under the Incremental Loans and the December 2019 Refinancing Loans were approximately $1,596.0 million and $415.9 million, respectively, categorized as a Level 2 instrument, as defined in Note 12. 2027 Senior Notes On July 16, 2019, HTUSA completed a private placement of $600.0 million aggregate principal amount of 5.5% Senior Notes due 2027 (the “2027 Senior Notes”) to several investment banks acting as initial purchasers, who subsequently resold the 2027 Senior Notes to persons reasonably believed to be qualified institutional buyers. The Company used the net proceeds from the offering of the 2027 Senior Notes, together with approximately $65.0 million in cash on hand, to redeem or prepay $625.0 million of its outstanding debt, consisting of (i) the outstanding $225.0 million principal amount of its 6.625 (ii) the outstanding $300.0 million principal amount of its 8.750 and (iii) $100.0 million of the outstanding principal amount of senior secured term loans under the Credit Agreement, as well as to pay the related premiums and fees and expenses, excluding accrued interest, associated with such redemption and prepayment. The 2027 Senior Notes are HTUSA’s general unsecured senior obligations, rank equally in right of payment with all existing and future senior debt of HTUSA and rank senior in right of payment to any existing and future subordinated debt of HTUSA. The 2027 Senior Notes are effectively subordinate to all of the existing and future secured debt of HTUSA to the extent of the value of the collateral securing such debt. The 2027 Senior Notes are unconditionally guaranteed on a senior basis by the Company and all of the Company’s restricted subsidiaries, other than HTUSA and certain immaterial subsidiaries, that guarantee the Credit Agreement. The guarantees are each guarantor’s senior unsecured obligations and rank equally in right of payment with such guarantor’s existing and future senior debt and senior in right of payment to any existing and future subordinated debt of such guarantor. The guarantees are effectively subordinated to all of the existing and future secured debt of each guarantor, including such guarantor’s guarantee under the Credit Agreement, to the extent of the value of the collateral securing such debt. The guarantees of a guarantor may be released under certain circumstances. The 2027 Senior Notes are structurally subordinated to all of the liabilities of the Company’s subsidiaries that do not guarantee the 2027 Senior Notes. The 2027 Senior Notes accrue interest at an annual rate of 5.5% payable semiannually in arrears on February 1 and August 1 of each year, beginning on February 1, 2020. The 2027 Senior Notes will mature on August 1, 2027, unless earlier exchanged, repurchased or redeemed. Except as described below, the 2027 Senior Notes may not be redeemed before August 1, 2022. Thereafter, some or all of the 2027 Senior Notes may be redeemed at any time at specified redemption prices, plus accrued and unpaid interest to the redemption date. At any time prior to August 1, 2022, some or all of the 2027 Senior Notes may be redeemed at a price equal to 100% of the aggregate principal amount thereof, plus a make-whole premium and accrued and unpaid interest to the redemption date. Also prior to August 1, 2022, up to 40% of the aggregate principal amount of the 2027 Senior Notes may be redeemed at a redemption price of 105.5% of the aggregate principal amount thereof, plus accrued and unpaid interest, with the net proceeds of certain equity offerings. In addition, the 2027 Senior Notes may be redeemed in whole but not in part at a redemption price equal to 100% of the principal amount plus accrued and unpaid interest and additional amounts, if any, to, but excluding, the redemption date, if on the next date on which any amount would be payable in respect of the 2027 Senior Notes, HTUSA or any guarantor is or would be required to pay additional amounts as a result of certain tax related events. If the Company undergoes a change of control, HTUSA will be required to make an offer to purchase all of the 2027 Senior Notes at a price in cash equal to 101% of the aggregate principal amount thereof plus accrued and unpaid interest to, but not including, the repurchase date, subject to certain exceptions. If the Company or certain of its subsidiaries engages in certain asset sales, HTUSA will be required under certain circumstances to make an offer to purchase the 2027 Senior Notes at 100% of the principal amount thereof, plus accrued and unpaid interest to the repurchase date. The indenture governing the 2027 Senior Notes contains covenants that limit the ability of the Company and its restricted subsidiaries to, among other things, pay dividends or distributions, repurchase equity, prepay junior debt and make certain investments, incur additional debt and issue certain preferred stock, incur liens on assets, engage in certain asset sales, merge, consolidate with or merge or sell all or substantially all of their assets, enter into transactions with affiliates, designate subsidiaries as unrestricted subsidiaries, and allow to exist certain restrictions on the ability of restricted subsidiaries to pay dividends or make other payments to the Company. Certain of the covenants will be suspended during any period in which the 2027 Senior Notes receive investment grade ratings. The indenture governing the 2027 Senior Notes also includes customary events of default. As of March 31, 2021, the interest rate on the 2027 Senior Notes was 5.50% and the effective interest rate was 5.76%. As of March 31, 2021, the fair value of the 2027 Senior Notes was approximately $640.5 million, categorized as a Level 2 instrument, as defined in Note 12.

Lease Obligations

Lease Obligations3 Months Ended
Mar. 31, 2021
Leases [Abstract]
Lease ObligationsNOTE 14 – LEASE OBLIGATIONS As of March 31, 2021, the Company had the following office space lease agreements in place for real properties:
Location
Approximate Square Feet
Lease Expiry Date
Dublin, Ireland
18,900
November 4, 2029
Lake Forest, Illinois
160,000
March 31, 2031
Novato, California
61,000
August 31, 2021
South San Francisco, California
20,000
January 31, 2030
Rockville, Maryland (1)
17,300
August 31, 2023 and February 28, 2025
Chicago, Illinois
9,200
December 31, 2028
Gaithersburg, Maryland (1)
7,200
June 30, 2022
Mannheim, Germany
4,800
December 31, 2022
Washington, D.C.
6,000
September 15, 2022
(1)
On March 15, 2021, the Company completed its acquisition of Viela. As part of the acquisition, the Company assumed two leases in Rockville, Maryland for both office and laboratory space and a lease in Gaithersburg, Maryland for office space. The above table does not include details of an agreement for lease entered into on October 14, 2019, relating to approximately 63,000 square feet of office space under construction in Dublin, Ireland. Lease commencement will begin when construction of the offices is completed by the lessor and the Company has access to begin the construction of leasehold improvements. The Company expects to receive access to the office space and commence the related lease in the second quarter of 2021 and incur leasehold improvement costs during 2021 in order to prepare the building for occupancy. As of March 31, 2021 and December 31, 2020, the Company had right-of-use lease assets included in other assets of $24.2 million and $34.4 million, respectively; current lease liabilities included in accrued expenses of $4.7 million and $4.1 million, respectively; and non-current lease liabilities included in other long-term liabilities of $43.9 million and $43.2 million, respectively, in its condensed consolidated balance sheets. In February 2021, the Company vacated the Lake Forest leased office building which represented a triggering event for impairment consideration of the right-of-use asset relating to this building. As a result of the Company vacating the Lake Forest office, the Company recorded an impairment charge of $12.4 million during the three months ended March 31, 2021, using an income approach based on market prices for similar properties provided by a third-party. This charge was reported within impairment of long-lived assets in the condensed consolidated statement of comprehensive loss. The Company recognizes rent expense on a monthly basis over the lease term based on a straight-line method. Rent expense was $1.6 million for the three months ended March 31, 2021 and 2020. The table below reconciles the undiscounted cash flows for each of the first five years and total of the remaining years to the lease liabilities recorded on the Company’s condensed consolidated balance sheet as of March 31, 2021 (in thousands):
2021 (April to December)
$
6,098
2022
7,063
2023
6,595
2024
6,936
2025
6,913
Thereafter
33,063
Total lease payments
66,668
Imputed interest
(18,041
)
Total lease liabilities
$
48,627
The weighted-average discount rate and remaining lease term for leases as of March 31, 2021 was 7.03% and 9.31 years, respectively.

Commitments and Contingencies

Commitments and Contingencies3 Months Ended
Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and ContingenciesNOTE 15 – COMMITMENTS AND CONTINGENCIES Purchase Commitments Under the Company’s supply agreement with AGC Biologics A/S (formerly known as CMC Biologics A/S) (“AGC Biologics”), the Company has agreed to purchase certain minimum annual order quantities of TEPEZZA drug substance. In addition, the Company must provide AGC Biologics with rolling forecasts of TEPEZZA drug substance requirements, with a portion of the forecast being a firm and binding order. At March 31, 2021, the Company had binding purchase commitments with AGC Biologics for TEPEZZA drug substance of €76.3 million ($89.5 million converted at a Euro-to-Dollar exchange rate as of March 31, 2021 of 1.1732), to be delivered through December 2023. Under the Company’s supply agreement with Catalent Indiana, LLC (“Catalent”), the Company must provide Catalent with rolling forecasts of TEPEZZA drug product requirements, with a portion of the forecast being a firm and binding order. The Company had binding purchase commitments with Catalent for TEPEZZA drug product of $6.4 million, to be delivered through March 2022. On December 17, 2020, the Company announced that it expected a short-term disruption in TEPEZZA supply as a result of recent U.S. government-mandated COVID-19 vaccine production orders pursuant to the Defense Production Act of 1950 (“DPA”) that dramatically restricted capacity available for the production of TEPEZZA at its drug product contract manufacturer, Catalent. Pursuant to the DPA, Catalent was ordered to prioritize certain COVID-19 vaccine manufacturing at Catalent, resulting in the cancellation of previously guaranteed and contracted TEPEZZA drug product manufacturing slots in December 2020, which were required to maintain TEPEZZA supply. To offset the reduced slots allowed by the DPA and Catalent, the Company accelerated plans to increase the production scale of TEPEZZA drug product. In March 2021, the FDA approved a prior approval supplement to the TEPEZZA Biologics Licensing Application (which was previously approved in January 2020), giving the Company authorization to manufacture more TEPEZZA drug product resulting in an increased number of vials with each manufacturing slot. The Company commenced resupply of TEPEZZA to the market in April 2021. Under the Company’s agreement with Bio-Technology General (Israel) Ltd (“BTG Israel”), the Company has agreed to purchase certain minimum annual order quantities and is obligated to purchase at least 80 percent of its annual world-wide bulk product requirements for KRYSTEXXA from BTG Israel. The term of the agreement runs until December 31, 2030, and will automatically renew for successive three-year f the manufacture of the is moved out of Israel, the Company may be required to obtain the approval of the Israel Innovation Authority (formerly known as Israeli Office of the Chief Scientist) (“IIA”) because certain KRYSTEXXA intellectual property was initially developed with a grant funded by the IIA. Under an agreement with Boehringer Ingelheim Biopharmaceuticals GmbH (“Boehringer Ingelheim Biopharmaceuticals”), Boehringer Ingelheim Biopharmaceuticals is required to manufacture and supply ACTIMMUNE and IMUKIN to the Company. Following the Company’s sale of the rights to IMUKIN in all territories outside of the United States, Canada and Japan to Clinigen Group plc (“Clinigen”), purchases of IMUKIN inventory are expected to be resold to Clinigen. The Company is required to purchase minimum quantities of finished medicine during the term of the agreement, which term extends to at least June 30, 2024. As of March 31, 2021, the minimum purchase commitment to Boehringer Ingelheim Biopharmaceuticals was $15.0 million (converted using a Euro-to-Dollar exchange rate of 1.1732 as of March 31, 2021) through June 2024. Excluding the above, additional purchase orders and other commitments relating to the manufacture of RAVICTI, BUPHENYL, PROCYSBI, PENNSAID 2%, DUEXIS, RAYOS, QUINSAIR and UPLIZNA of $21.0 million were outstanding at March 31, 2021. Contingencies The Company is subject to claims and assessments from time to time in the ordinary course of business. The Company’s management does not believe that any such matters, individually or in the aggregate, will have a material adverse effect on the Company’s business, financial condition, results of operations or cash flows. In addition, the Company from time to time has billing disputes with vendors in which amounts invoiced are not in accordance with the terms of their contracts. In November 2015, the Company received a subpoena from the U.S. Attorney’s Office for the Southern District of New York requesting documents and information related to its patient assistance programs and other aspects of its marketing and commercialization activities. The Company is unable to predict how long this investigation will continue or its outcome, but it anticipates that it may continue to incur significant costs in connection with the investigation, regardless of the outcome. The Company may also become subject to similar investigations by other governmental agencies. The investigation by the U.S. Attorney’s Office and any additional investigations of the Company’s patient assistance programs and sales and marketing activities may result in damages, fines, penalties or other administrative sanctions against the Company. On March 5, 2019, the Company received a civil investigative demand (“CID”) from the United States Department of Justice (“DOJ”) pursuant to the Federal False Claims Act regarding assertions that certain of the Company’s payments to pharmacy benefit managers (“PBMs”) were potentially in violation of the Anti-Kickback Statute. The CID requests certain documents and information related to the Company’s payments to PBMs, pricing and the Company’s patient assistance program regarding DUEXIS, VIMOVO and PENNSAID 2%. The Company is cooperating with the investigation. While the Company believes that its payments and programs are compliant with the Anti-Kickback Statute, no assurance can be given as to the timing or outcome of the DOJ’s investigation, or that it will not result in a material adverse effect on the Company’s business. Royalty and Milestone Agreements TEPEZZA Under the acquisition agreement for River Vision, the Company agreed to pay up to $325.0 million upon the attainment of various milestones, composed of $100.0 million related to FDA approval and $225.0 million related to net sales thresholds for TEPEZZA. The Company made the $100.0 million milestone payment related to FDA approval during the first quarter of 2020. The remaining aggregate potential milestone payments of $225.0 million are payable based on certain TEPEZZA worldwide net sales thresholds being achieved as noted in the following table:
TEPEZZA Worldwide Net Sales Threshold
Milestone Payment
>$250 million
$50 million
>$375 million
$75 million
>$500 million
$100 million The agreement also includes a royalty payment of 3 percent of the portion of annual worldwide net sales exceeding $300.0 million. S.R. One and Lundbeckfond, as two of the former River Vision stockholders, both held rights to receive approximately 35.66% of any future TEPEZZA payments. As a result of the Company’s agreements with S.R. One and Lundbeckfond in April 2020, the Company’s remaining net obligations to make TEPEZZA payments for sales milestones and royalties to the former stockholders of River Vision was reduced by approximately 70.25%, after including payments to a third party. Under the Company’s license agreement with Roche, the Company is required to pay Roche up to CHF103.0 million ($109.2 million when converted using a CHF-to-Dollar exchange rate at March 31, 2021 of 1.0598) upon the attainment of various development, regulatory and sales milestones for TEPEZZA. The Company made a milestone payment of CHF5.0 million ($5.2 million when converted using a CHF-to-Dollar exchange rate at the date of payment of 1.0382) during the first quarter of 2020. The agreement with Roche also includes tiered royalties on annual worldwide net sales between 9 and 12 percent. During the year ended December 31, 2020, the Company recorded a liability of $123.4 million in accrued expenses representing net sales milestones for TEPEZZA. The timing of the payments was dependent on when the applicable milestone thresholds were attained. In February 2021, under the license agreement with Roche, the Company made a milestone payment of CHF50.0 million ($56.1 million when converted using a CHF-to-Dollar exchange rate at the date of payment of 1.1228). As of March 31, 2021, a liability of $67.0 million was remaining in accrued expenses which represents the net sales milestones payable to the former River Vision stockholders. The Company paid the milestones to the former River Vision stockholders in April 2021. Following this payment, the Company has no further TEPEZZA net sales milestone obligations remaining to Roche and the former River Vision stockholders. Under the Company’s license agreement with Lundquist Institute (formerly known as Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center) (“Lundquist”), the Company is required to pay Lundquist a royalty payment of less than 1 percent of TEPEZZA net sales. The royalty terminates upon Under the Company’s license agreement with Boehringer Ingelheim Biopharmaceuticals, the Company is required to pay Boehringer Ingelheim Biopharmaceuticals milestone payments totaling less than $2.0 million upon the achievement of certain TEPEZZA sales milestones. Other Agreements On April 1, 2020, the Company acquired Curzion for an upfront payment of $45.0 million with additional payments of up to $15.0 million contingent on the achievement of certain development and regulatory milestones. Under separate agreements with two additional parties, the Company is also required to make contingent payments upon the achievement of certain development and regulatory milestones and certain net sales thresholds. These separate agreements also include mid to high-single-digit royalty payments based on the portion of annual worldwide net sales. During the year ended December 31, 2020, the Company committed to invest as a strategic limited partner in four venture capital funds: Forbion Growth Opportunities Fund I C.V., Forbion Capital Fund V C.V., Aisling Capital V, L.P. and RiverVest Venture Fund V, L.P. As of March 31, 2021, the total carrying amount of the Company’s investments in these funds was $17.5 million, which is included in other assets in the condensed consolidated balance sheet, and includes $3.8 million in net cash payments for investments made during the first quarter of 2021. As of March 31, 2021, the Company’s total future commitments to these funds were $51.7 million. During the three months ended March 31, 2021, the Company recorded investment income of $2.9 million in the other income, net line item of the Company’s consolidated statement of comprehensive loss related to these funds. On November 21, 2020, the Company entered into a global collaboration and license agreement with Halozyme that gives the Company exclusive access to Halozyme’s ENHANZE drug delivery technology for SC formulation of medicines targeting IGF-1R. The Company intends to use ENHANZE to develop a SC formulation of TEPEZZA. Under the terms of the agreement, the Company paid Halozyme an upfront cash payment of $30.0 million in December 2020 and agreed to pay additional potential future milestone payments of up to $160.0 million contingent on the satisfaction of certain development and sales thresholds. As of March 31, 2021, the Company had $32.1 million of non-cancellable advertising commitments due within one year, primarily related to agreements for advertising for TEPEZZA and KRYSTEXXA. Indemnification In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future, but have not yet been made. The Company may record charges in the future as a result of these indemnification obligations. In accordance with its memorandum and articles of association, the Company has indemnification obligations to its officers and directors for certain events or occurrences, subject to certain limits, while they are serving at the Company’s request in such capacity. Additionally, the Company has entered into, and intends to continue to enter into, separate indemnification agreements with its directors and executive officers. These agreements, among other things, require the Company to indemnify its directors and executive officers for certain expenses, including attorneys’ fees, judgments, fines and settlement amounts incurred by a director or executive officer in any action or proceeding arising out of their services as one of the Company’s directors or executive officers, or any of the Company’s subsidiaries or any other company or enterprise to which the person provides services at the Company’s request. The Company also has a director and officer insurance policy that enables it to recover a portion of any amounts paid for current and future potential claims. All of the Company’s officers and directors have also entered into separate indemnification agreements with HTUSA.

Legal Proceedings

Legal Proceedings3 Months Ended
Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Legal ProceedingsNOTE 16 - LEGAL PROCEEDINGS PENNSAID 2% On August 18, 2016, the Company filed suit in the United States District Court for the District of New Jersey against Actavis Laboratories UT, Inc. and Actavis plc DUEXIS On May 29, 2018, the Company received notice from Alkem Laboratories, Inc. (“Alkem”) that it had filed an Abbreviated New Drug Application (“ANDA”) with the FDA seeking approval of a generic version of DUEXIS. The ANDA contained a Paragraph IV Patent Certification alleging that the patents covering DUEXIS are invalid and/or will not be infringed by Alkem’s manufacture, use or sale of the medicine for which the ANDA was submitted. The Company filed suit in the United States District Court of Delaware against Alkem on July 9, 2018, seeking an injunction to prevent the approval of Alkem’s ANDA and/or to prevent Alkem from selling a generic version of DUEXIS. The litigation went to trial on September 14, 2020. On November 30, 2020, the District Court issued an adverse judgment against the Company, invalidating U.S Patent No. 8,607,033 and finding that Alkem’s generic product would not infringe the ‘033 patent. And following an adverse claim construction ruling, the District Court entered a judgment that the Alkem generic product would not infringe U.S. Patent No. 8,607,451, subject to the Company’s right to appeal the District Court’s claim construction ruling. On December 23, 2020, the Company initiated an appeal of the adverse judgments on the ‘033 and ‘451 patents with the Federal Circuit Court of Appeals. On September 26, 2018, the Company received notice from Teva Pharmaceuticals USA, Inc. (“Teva USA”) that it had filed an ANDA with the FDA seeking approval of a generic version of DUEXIS. The ANDA contained a Paragraph IV Patent Certification alleging that the patents covering DUEXIS are invalid and/or will not be infringed by Teva USA’s manufacture, use or sale of the medicine for which the ANDA was submitted. The Company filed suit in the United States District Court of New Jersey against Teva USA on July 2, 2020, seeking to prevent Teva USA from selling a generic version of DUEXIS. The parties are currently engaged in discovery. The court has not yet set a trial date. VIMOVO On February 18, 2020, the FDA granted final approval for Dr. Reddy’s Laboratories Inc. and Dr. Reddy’s Laboratories Ltd. (collectively, “Dr. Reddy’s”) generic version of VIMOVO. On February 27, 2020, Dr. Reddy’s launched its generic version of VIMOVO in the United States, and the Company now faces generic competition with respect to VIMOVO. The Company continues to assert claims of infringement against Dr. Reddy’s based on U.S. Patent No. 8,858,996 and U.S. Patent No. 9,161,920 in the District Court for the District of New Jersey. On November 19, 2018, the District Court granted Dr. Reddy’s summary judgment ruling that U.S Patent Numbers 9,220,698 and 9,393,208 are invalid, and on January 21, 2019, it entered final judgment against the ‘698 and ‘208 patents and U.S. Patent Number 8,945,621. On February 21, 2019, the Company appealed the adverse judgments on the ‘208 and ‘698 patents to the Federal Circuit Court of Appeals. On January 6, 2021, the Federal Circuit affirmed the District Court judgments invalidating the ‘208 and ‘698 patents. PROCYSBI On June 27, 2020, the Company received notice from Lupin Limited (“Lupin”) that it had filed an ANDA with the FDA seeking approval of a generic version of PROCYSBI. The ANDA contained a Paragraph IV Patent Certification alleging that the patents covering PROCYSBI are invalid and/or will not be infringed by Lupin’s manufacture, use or sale of the medicine for which the ANDA was submitted. The Company filed suit in the United States District Court of New Jersey against Lupin on August 11, 2020, seeking to prevent Lupin from selling a generic version of PROCYSBI.

Share-Based and Long-Term Incen

Share-Based and Long-Term Incentive Plans3 Months Ended
Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Share-Based and Long-Term Incentive PlansNOTE 17 – SHARE-BASED AND LONG-TERM INCENTIVE PLANS The Company’s equity incentive plans at March 31, 2021 included its 2011 Equity Incentive Plan, as amended, 2014 Employee Share Purchase Plan, as amended (“2014 ESPP”), Amended and Restated 2014 Equity Incentive Plan (“2014 EIP”), 2014 Non-Employee Equity Plan, as amended (“2014 Non-Employee Plan”), 2020 Employee Share Purchase Plan (“2020 ESPP”), Amended and Restated 2020 Equity Incentive Plan (“2020 EIP”) and the Viela Amended and Restated 2018 Equity Incentive Plan (“Viela 2018 EIP”). The Viela 2018 EIP was subsequently renamed the Horizon Therapeutics Public Limited Company Amended and Restated 2018 Equity Incentive Plan on April 28, 2021. On February 17, 2021, the Compensation Committee of the Company’s Board of Directors (the “Compensation Committee”) approved amending the 2020 EIP, subject to shareholder approval, including increasing the number of ordinary shares available for the grant of equity awards to the Company’s employees by an additional 7,000,000 shares. On April 29, 2021, the shareholders of the Company approved such amendment to the 2020 EIP. As of March 31, 2021, an aggregate of 2,994,723 ordinary shares were authorized and available for future issuance under the 2014 ESPP and 2020 ESPP combined, an aggregate of 8,759,022 ordinary shares were authorized and available for future grants under the 2020 EIP, an aggregate of 574,193 ordinary shares were authorized and available for future grants under the 2014 Non-Employee Plan and an aggregate of 2,359,550 ordinary shares were authorized and available for future grants under the Viela 2018 EIP. Stock Options The following table summarizes stock option activity during the three months ended March 31, 2021:
Options
Weighted Average Exercise Price
Weighted Average Contractual Term Remaining (in years)
Aggregate Intrinsic Value (in thousands)
Outstanding as of December 31, 2020
7,129,615
$
21.24
4.60
$
370,073
Assumed in acquisition (1)
1,318,053
41.23
Exercised
(661,780
)
30.06


Forfeited
(268
)
17.19


Expired
(234
)
17.32


Outstanding as of March 31, 2021
7,785,386
23.88
4.82
530,665
Exercisable as of March 31, 2021
6,771,755
$
21.40
4.28
$
478,349
Stock options typically have a contractual term of ten years from grant date.
(1)
On March 15, 2021, the Company completed its acquisition of Viela. Under the terms of the merger agreement for Viela, all outstanding Viela stock options assumed by the Company with vesting dates after June 1, 2021, were converted into stock options to purchase the Company’s ordinary shares. As of March 15, 2021, options previously exercisable for an aggregate of 2,180,159 shares of Viela’s common stock that were converted at a rate of 0.60 to 1 based on the merger agreement, into options to purchase 1,318,053 of the Company’s ordinary shares, were outstanding. Restricted Stock Units The following table summarizes restricted stock unit activity for the three months ended March 31, 2021:
Number of Units
Weighted Average Grant-Date Fair Value Per Unit
Outstanding as of December 31, 2020
5,909,120
$
27.87
Granted
1,851,309
73.82
Vested
(2,350,056
)
23.19
Forfeited
(95,177
)
56.21
Outstanding as of March 31, 2021
5,315,196
$
45.44
The grant-date fair value of restricted stock units is the closing price of the Company’s ordinary shares on the date of grant. Performance Stock Unit Awards The following table summarizes performance stock unit awards (“PSUs”) activity for the three months ended March 31, 2021:
Number of Units
Weighted Average Grant-Date Fair Value Per Unit
Average Illiquidity Discount
Recorded Weighted Average Fair Value Per Unit
Outstanding as of December 31, 2020
2,610,924
Granted
450,577
$
93.73
8.64
%
$
85.64
Forfeited
(24,450
)
93.73
9.21
%
85.10
Vested
(2,021,657
)
21.21
2.66
%
20.65
Performance Based Adjustments (1)
512,819
25.42
7.27
%
23.57
Outstanding as of March 31, 2021
1,528,213
(1)
Represents adjustment based on the net sales performance criteria meeting 162.5% of target as of December 31, 2020 for the 2020 PSUs (as defined below), the net sales performance criteria meeting 200.0% of target as of December 31, 2020 for the TEPEZZA PSUs (as defined below) and meeting total shareholder return (“TSR”) performance at 200.0% for the PSUs that were awarded to key executive participants on January 5, 2018. On January 4, 2021, the Company awarded PSUs to key executive participants (“2021 PSUs”). The 2021 PSUs utilize three long-term performance metrics, a component tied to technical operations milestones for the Company over the next two years, a component tied to research and development milestones for the Company over the next three years and a component tied to relative three-year compounded annual TSR as follows:

50% of the granted 2021 PSUs that may vest (such portion of the PSU award, the “2021 Relative TSR PSUs”) are determined by reference to the level of the Company’s relative TSR over the three-year

25% of the 2021 PSUs that may vest (such portion of the PSU award, the “2021 Tech Ops PSUs”) are determined by reference to the Company’s achievement of certain performance objectives related to technical operations.

25% of the 2021 PSUs that may vest (such portion of the PSU award, the “2021 R&D PSUs”) are determined by reference to the Company’s achievement of certain performance objectives related to research and development. On January 3, 2020, the Company awarded PSUs to key executive participants (“2020 PSUs”). The 2020 PSUs utilize two performance metrics, a short-term component tied to business performance and a long-term component tied to relative compounded annual TSR, as follows:

30% of the granted 2020 PSUs that may vest (such portion of the PSU award, the “2020 Relative TSR PSUs”) are determined by reference to the level of the Company’s relative TSR over the three-year

70% of the 2020 PSUs that may vest (such portion of the PSU award, the “2020 Net Sales PSUs”) are determined by reference to the Company’s net sales for certain components of its orphan segment. As a result of the impact of the COVID-19 pandemic on certain aspects of the Company’s business in 2020, the performance goals associated with certain of the Company’s performance-based equity awards no longer reflected the Company’s expectations, causing the awards to lose their incentive to employees. Accordingly, on July 28, 2020 the Compensation Committee approved a modification to 57% of the 2020 Net Sales PSUs awarded on January 3, 2020 that were to vest based on KRYSTEXXA 2020 net sales. Those 2020 Net Sales PSUs related to KRYSTEXXA may now be earned based on net sales of KRYSTEXXA achieved by the end of a modified 18-month performance period ending July 1, 2021 instead of a 12-month performance period ending December 31, 2020. As a result, the first one-third of any 2020 PSUs earned will vest on July 1, 2021 and the vesting of the remaining two-thirds is unchanged and will vest one-third each on January 5, 2022 and on January 5, 2023. There were 12 participants impacted by the modification. The total compensation cost resulting from the modification was approximately $12.0 million and is being recognized over the remaining requisite service period. All PSUs outstanding at March 31, 2021 may vest in a range of between 0% and 200%, with the exception of the modified KRYSTEXXA 2020 Net Sales PSUs which are capped at 150%, based on the performance metrics described above. The Company accounts for the 2020 PSUs and 2021 PSUs as equity-settled awards in accordance with ASC 718. Because the value of the 2020 Relative TSR PSUs and 2021 Relative TSR PSUs are dependent upon the attainment of a level of TSR, it requires the impact of the market condition to be considered when estimating the fair value of the 2020 Relative TSR PSUs and 2021 Relative TSR PSUs. As a result, the Monte Carlo model is applied and the most significant valuation assumptions used related to the 2021 PSUs during the three months ended March 31, 2021, include:
Valuation date stock price
$
72.54
Expected volatility
45.8
%
Risk free rate
0.2
% The value of the 2020 Net Sales PSUs related to KRYSTEXXA and 2021 Tech Ops PSUs and 2021 R&D PSUs is calculated at the end of each quarter based on the expected payout percentage based on estimated full-period performance against targets, and the Company adjusts the expense quarterly. On January 4, 2019, the Company awarded a company-wide grant of PSUs (the “TEPEZZA PSUs”). Vesting of the TEPEZZA PSUs was contingent upon receiving shareholder approval of amendments to the 2014 EIP, which approval was received on May 2, 2019. The TEPEZZA PSUs were generally eligible to vest contingent upon receiving approval of the TEPEZZA biologics license application Share-Based Compensation Expense The following table summarizes share-based compensation expense included in the Company’s condensed consolidated statements of operations for the three months ended March 31, 2021 and 2020 (in thousands):
For the Three Months Ended March 31,
2021
2020
Share-based compensation expense
Cost of goods sold
$
1,936
$
2,689
Research and development
5,616
6,376
Selling, general and administrative
53,614
47,356
Total share-based compensation expense
$
61,166
$
56,421
During the three months ended March 31, 2021 and 2020, the Company recognized $53.7 million and $14.1 million of tax benefit, respectively, related to share-based compensation resulting primarily from the fair value of equity awards at the time of the exercise of stock options and vesting of restricted stock units and PSUs. As of March 31, 2021, the Company estimates that pre-tax unrecognized compensation expense of $341.5 million for all unvested share-based awards, including stock options, restricted stock units and PSUs, will be recognized through the second quarter of 2023. The Company expects to satisfy the exercise of stock options and future distribution of shares for restricted stock units and PSUs by issuing new ordinary shares which have been reserved under the 2020 EIP and the Viela 2018 EIP. Cash Incentive Program On January 5, 2018, the Compensation Committee approved a performance cash incentive program for the Company’s executive leadership team, including its executive officers (the “Cash Incentive Program”). Participants receiving awards under the Cash Incentive Program are eligible to earn a cash bonus based upon the achievement of specified Company goals, which both performance criteria were met on or before December 31, 2018. The Company determined that the cash bonus award under the Cash Incentive Program is to be paid out at the maximum 150% target level of $14.1 million. The first and second installments were paid in January 2019 and January 2020, respectively, and the remaining installment vested and was paid in January 2021. The Company accounted for the Cash Incentive Program as a deferred compensation plan under ASC 710 and is recognizing the payout expense using straight-line recognition through the end of the 36-month vesting period. During the three months ended March 31, 2021, the Company did not record an expense related to the Cash Incentive Program as it was fully expensed as of December 31, 2020.

Income Taxes

Income Taxes3 Months Ended
Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income TaxesNOTE 18 – INCOME TAXES The Company accounts for income taxes based upon an asset and liability approach. Deferred tax assets and liabilities represent the future tax consequences of the differences between the financial statement carrying amounts of assets and liabilities versus the tax basis of assets and liabilities. Under this method, deferred tax assets are recognized for deductible temporary differences and operating loss and tax credit carryforwards. Deferred tax liabilities are recognized for taxable temporary differences. Deferred tax assets are reduced by valuation allowances when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized. Deferred tax assets and liabilities are recorded at the currently enacted rates which will be in effect at the time when the temporary differences are expected to reverse in the country where the underlying assets and liabilities are located. The impact of tax rate changes on deferred tax assets and liabilities is recognized in the period in which the change is enacted. The following table presents the benefit for income taxes for the three months ended March 31, 2021 and 2020 (in thousands):
For
2021
2020
Loss before benefit for income taxes
$
(171,102
)
$
(32,617
)
Benefit for income taxes
(47,751
)
(19,026
)
Net loss
$
(123,351
)
$
(13,591
)
During the three months ended March 31, 2021, the Company recorded a benefit for income taxes of $47.8 million. During the three months ended March 31, 2020, the Company recorded a benefit for income taxes of $19.0 million. The increase in benefit for income taxes recorded during the three months ended March 31, 2021 compared to the three months ended March 31, 2020, resulted primarily from the increase in the tax benefits recognized on share-based compensation.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)3 Months Ended
Mar. 31, 2021
Accounting Policies [Abstract]
Basis of PresentationBasis of Presentation Unless otherwise indicated or the context otherwise requires, references to “Horizon”, the “Company”, “we”, “us” and “our” refer to Horizon Therapeutics plc and its consolidated subsidiaries. On March 15, 2021, the Company completed its acquisition of Viela Bio, Inc. (“Viela”) and acquired all of the issued and outstanding shares of Viela’s common stock for $53.00 per share. The total consideration for the acquisition was approximately $3.0 billion, including cash acquired of $342.3 million. Following the completion of the acquisition, Viela became a wholly-owned subsidiary of the Company. The unaudited condensed consolidated financial statements presented herein include the results of operations of the acquired business from the date of acquisition. The unaudited condensed consolidated financial statements presented herein have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, the financial statements do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all adjustments, including normal recurring adjustments, considered necessary for a fair statement of the financial statements have been included. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. The December 31, 2020 condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP.
Recent Accounting PronouncementsRecent Accounting Pronouncements From time to time, the Company adopts new accounting pronouncements issued by the Financial Accounting Standards Board (“FASB”) or other standard-setting bodies. In December 2019, the FASB issued Accounting Standards Update No. 2019-12, Income Taxes (Topic 740): Simplification and reduce the cost of accounting for income taxes Other recent authoritative guidance issued by the FASB (including technical corrections to the Accounting Standards Codification (“ASC”)), the American Institute of Certified Public Accountants and the Securities and Exchange Commission (“SEC”) did not, or are not expected to, have a material impact on the Company’s condensed consolidated financial statements and related disclosures.
Intangible AssetsIntangible Assets Indefinite-lived intangible assets consist of capitalized in-process research and development (“IPR&D”). IPR&D assets represent capitalized incomplete research projects that the Company acquired through business combinations. Such assets are initially measured at their acquisition date fair values and are tested for impairment, until completion or abandonment of research and development efforts associated with the projects. An IPR&D asset is considered abandoned when research and development efforts associated with the asset have ceased, and there are no plans to sell or license the asset or derive value from the asset. At that point, the asset is considered to be impaired and is written off. Upon successful completion of each project, the Company will make a determination about the then remaining useful life of the intangible asset and begin amortization. The Company tests its indefinite-lived intangibles, including IPR&D assets, for impairment annually during the fourth quarter and more frequently if events or changes in circumstances indicate that it is more likely than not that the asset is impaired.

Net Loss per Share (Tables)

Net Loss per Share (Tables)3 Months Ended
Mar. 31, 2021
Earnings Per Share [Abstract]
Basic and Diluted Net Loss per ShareThe following table presents basic and diluted net loss per share for the three months ended March 31, 2021 and 2020 (in thousands, except share and per share data):
For the Three Months Ended March 31,
2021
2020
Basic and diluted net loss per share calculation:
Numerator - net loss
$
(123,351
)
$
(13,591
)
Denominator - weighted average of ordinary shares outstanding
223,920,768
190,072,112
Basic and diluted net loss per share
$
(0.55
)
$
(0.07
)

Acquisitions, Divestitures an_2

Acquisitions, Divestitures and Other Arrangements (Tables)3 Months Ended
Mar. 31, 2021
Business Combinations [Abstract]
Schedule of Total Consideration for the AcquisitionsThe total consideration for the acquisition was approximately $3.0 billion, including cash acquired of $342.3 million, and was composed of the following (in thousands):
E quity value (54,988,820 shares at $53.00 per share
$
2,914,407
Net settlements on the exercise of stock options
78,554
Consideration for exchange of Viela stock options
1,130
Total consideration
$
2,994,091
Schedule of Recognized Identified Assets Acquired and Liabilities AssumedThe following table summarizes the preliminary fair values assigned to the assets acquired and the liabilities assumed by the Company along with the resulting goodwill (in thousands):
Allocation
Deferred tax liabilities, net
$
(457,928
)
Accrued expenses
(73,401
)
Other long-term liabilities
(22,631
)
Accounts payable
(4,768
)
Accrued trade discounts and rebates
(1,492
)
Marketable securities
400
Property, plant and equipment
1,747
Other assets
3,253
Accounts receivable
8,053
Prepaid expenses and other current assets
16,444
Inventories
149,348
Cash and cash equivalents
342,347
In-process research and development
910,000
Developed technology
1,460,000
(Liabilities assumed) and assets acquired
2,331,372
Goodwill
662,719
Fair value of consideration paid
$
2,994,091
Gain (Loss) on Sale of AssetsThe following table presents the pro forma combined results of the Company and Viela for the three months ended March 31, 2021 and 2020 as if the acquisition of Viela had occurred on January 1, 2020:
For the Three Months Ended March 31,
2021
2020
As reported
Pro forma adjustments
Pro forma
As reported
Pro forma adjustments
Pro forma
Net sales
$
342,406
$
10,588
$
352,994
$
355,909
$

$
355,909
Net loss
(123,351
)
(43,556
)
(166,907
)
(13,591
)
(120,002
)
(133,593
)

Inventories (Tables)

Inventories (Tables)3 Months Ended
Mar. 31, 2021
Inventory Disclosure [Abstract]
Components of InventoriesThe components of inventories as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Raw materials
$
29,861
$
11,760
Work-in-process
140,813
33,167
Finished goods
67,632
30,356
Inventories, net
$
238,306
$
75,283

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)3 Months Ended
Mar. 31, 2021
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current AssetsPrepaid expenses and other current assets as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Advance payments for inventory
$
167,753
$
137,680
Deferred charge for taxes on intercompany profit
58,617
52,306
Prepaid income taxes and income tax receivable
23,456
102
Rabbi trust assets
21,709
18,423
Other prepaid expenses and other current assets
62,907
43,434
Prepaid expenses and other current assets
$
334,442
$
251,945

Property and Equipment (Tables)

Property and Equipment (Tables)3 Months Ended
Mar. 31, 2021
Property Plant And Equipment [Abstract]
Property and EquipmentProperty and equipment as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Buildings
$
128,268
$
80,341
Land and land improvements
38,880
38,076
Machinery and equipment
16,910
4,695
Software
14,487
14,618
Furniture and fixtures
12,017
5,973
Leasehold improvements
9,558
26,323
Construction in process
7,370
63,656
Other
4,917
3,146
232,407
236,828
Less accumulated depreciation
(30,550
)
(47,791
)
Property and equipment, net
$
201,857
$
189,037

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)3 Months Ended
Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Goodwill for Reportable SegmentsThe table below presents goodwill for the Company’s reportable segments as of March 31, 2021 (in thousands):
Orphan
Inflammation
Total
Balance at December 31, 2020
$
357,498
$
56,171
$
413,669
Acquired during the period
662,719

662,719
Balance at March 31, 2021
$
1,020,217
$
56,171
$
1,076,388
Amortizable Intangible AssetsIntangible assets as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Cost
Accumulated Amortization
Net Book Value
Cost Basis
Accumulated Amortization
Net Book Value
Developed technology
$
4,587,515
$
(1,380,104
)
$
3,207,411
$
3,093,886
$
(1,313,934
)
$
1,779,952
In-process research and development (1)
880,000

880,000



Customer relationships
8,100
(5,290
)
2,810
8,100
(5,090
)
3,010
Total intangible assets
$
5,475,615
$
(1,385,394
)
$
4,090,221
$
3,101,986
$
(1,319,024
)
$
1,782,962
(1)
The Company acquired IPR&D of $910.0 million relating to Viela. On March 24, 2021, the Company announced that its strategic partner, Mitsubishi Tanabe Pharma Corporation, had received manufacturing and marketing approval of UPLIZNA in Japan. As a result, the Company transferred $30.0 million of IPR&D to developed technology. As of March 31, 2021, the remaining IPR&D relating to the Viela acquisition was $880.0 million.
Estimated Future Amortization ExpenseAs of March 31, 2021, estimated future amortization expense was as follows (in thousands):
2021 (April to December)
$
268,242
2022
355,047
2023
354,582
2024
353,102
2025
350,861
Thereafter
1,528,387
Total
$
3,210,221

Accrued Expenses (Tables)

Accrued Expenses (Tables)3 Months Ended
Mar. 31, 2021
Payables And Accruals [Abstract]
Schedule of Accrued Liabilities / ExpensesAccrued expenses as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Payroll-related expenses
$
72,906
$
121,577
Accrued milestone payments
69,962
123,442
Consulting and professional services
50,635
21,893
Allowances for returns
38,089
40,918
R&D and manufacturing programs
31,376
17,289
Accrued royalties
23,839
68,006
Advertising and marketing
17,468
12,428
Pricing review liability
17,169
16,046
Accrued interest
7,784
14,207
Accrued other
60,398
49,761
Accrued expenses
$
389,626
$
485,567

Accrued Trade Discounts and R_2

Accrued Trade Discounts and Rebates (Tables)3 Months Ended
Mar. 31, 2021
Valuation And Qualifying Accounts Disclosure [Line Items]
Schedule of Accrued Liabilities / ExpensesAccrued expenses as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Payroll-related expenses
$
72,906
$
121,577
Accrued milestone payments
69,962
123,442
Consulting and professional services
50,635
21,893
Allowances for returns
38,089
40,918
R&D and manufacturing programs
31,376
17,289
Accrued royalties
23,839
68,006
Advertising and marketing
17,468
12,428
Pricing review liability
17,169
16,046
Accrued interest
7,784
14,207
Accrued other
60,398
49,761
Accrued expenses
$
389,626
$
485,567
Accrued Trade Discounts and Rebates [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Schedule of Accrued Liabilities / ExpensesAccrued trade discounts and rebates as of , 2020 (in thousands):
March 31, 2021
December 31, 2020
Accrued government rebates and chargebacks
$
177,758
$
172,893
Accrued co-pay and other patient assistance
80,449
96,924
Accrued commercial rebates and wholesaler fees
67,025
82,646
Accrued trade discounts and rebates
$
325,232
$
352,463
Invoiced commercial rebates and wholesaler fees, co-pay and other patient assistance costs, and government rebates and chargebacks in accounts payable
2,608
1,452
Total customer-related accruals and allowances
$
327,840
$
353,915
Customer-related Accruals and Allowances [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Schedule of Customer-Related Accruals and AllowancesThe following table summarizes changes in the Company’s customer-related accruals and allowances from December 31, 2020 to March 31, 2021 (in thousands):
Government
Co-Pay and
Wholesaler Fees
Rebates and
Other Patient
and Commercial
Chargebacks
Assistance
Rebates
Total
Balance at December 31, 2020
$
172,893
$
96,924
$
84,098
$
353,915
Current provisions relating to sales during the three months ended March 31, 2021
146,491
199,031
63,971
409,493
Adjustments relating to prior-year sales
(3,716
)
(52
)
(758
)
(4,526
)
Payments relating to sales during the three months ended March 31, 2021
(31,764
)
(124,234
)
(10,799
)
(166,797
)
Payments relating to prior-year sales
(107,557
)
(90,728
)
(67,452
)
(265,737
)
Viela acquisition on March 15, 2021
1,411
11
70
1,492
Balance at March 31, 2021
$
177,758
$
80,952
$
69,130
$
327,840

Segment and Other Information (

Segment and Other Information (Tables)3 Months Ended
Mar. 31, 2021
Segment Reporting [Abstract]
Summary of Net Sales by Medicine for Reportable SegmentsThe following table reflects net sales by medicine for the Company’s reportable segments for the three months ended March 31, 2021 and 2020 (in thousands):
Three Months Ended March 31
2021
2020
KRYSTEXXA
$
106,757
$
93,248
RAVICTI
72,817
61,189
PROCYSBI
43,363
38,343
ACTIMMUNE
28,763
26,541
TEPEZZA
2,065
23,452
UPLIZNA
1,873

BUPHENYL
1,660
2,313
QUINSAIR
209
277
Orphan segment net sales
$
257,507
$
245,363
PENNSAID 2%
45,817
41,563
DUEXIS
19,465
31,346
RAYOS
15,272
18,209
VIMOVO
4,345
19,428
Inflammation segment net sales
$
84,899
$
110,546
Total net sales
$
342,406
$
355,909
Summary of Reconciliations of Segment Operating IncomeThe table below provides reconciliations of the Company’s segment operating income to the Company’s total loss before benefit for income taxes for the three months ended March 31, 2021 and 2020 (in thousands):
For the Three Months Ended March 31,
2021
2020
Segment operating income:
Orphan
$
1,054
$
54,356
Inflammation
42,680
51,942
Reconciling items:
Amortization and step-up:
Intangible amortization expense
(66,369
)
(58,575
)
Inventory step-up expense
(911
)

Share-based compensation
(61,166
)
(56,421
)
Acquisition/divestiture-related costs
(49,391
)
(284
)
Interest expense, net
(13,460
)
(17,344
)
Impairment of long-lived assets
(12,371
)

Depreciation
(4,451
)
(7,165
)
Restructuring and realignment costs
(6,093
)

Upfront, progress and milestone payments related to license and collaboration agreements
(3,000
)

Foreign exchange (loss) gain
(848
)
776
Drug substance harmonization costs

(290
)
Fees related to refinancing activities

(54
)
Other income, net
3,224
442
Loss before benefit for income taxes
$
(171,102
)
$
(32,617
)
Schedule of Gross Sales to Customers Included in Reportable Segments and All Other Customers as a GroupThe following table presents the amount and percentage of gross sales to customers that represented more than 10% of the Company’s gross sales included in its two reportable segments and all other customers as a group for the three months ended March 31, 2021 and 2020 (in thousands, except percentages):
For the Three Months Ended March 31,
2021
2020
Amount
% of
Amount
% of Gross
Sales
Sales
Customer A
$
248,740
33
%
$
246,775
31
%
Customer B
184,687
24
%
207,277
26
%
Customer C
118,037
15
%
133,876
17
%
Customer D
90,619
12
%
84,788
10
%
Other Customers
119,449
16
%
130,806
16
%
Gross Sales
$
761,532
100
%
$
803,522
100
%
Summary of Net Sales Attributed to Geographic SourcesGeographic revenues are determined based on the country in which the Company’s customers are located. The following table presents a summary of net sales attributed to geographic sources for the three months ended March 31, 2021 and 2020 (in thousands, except percentages):
Three Months Ended March 31, 2021
Three Months Ended March 31, 2020
Amount
% of Total Net Sales
Amount
% of Total Net Sales
United States
$
340,330
99%
$
354,016
100%
Rest of world
2,076
1%
1,893
*
Net sales
$
342,406
$
355,909
*Less than 1%

Fair Value Measurements (Tables

Fair Value Measurements (Tables)3 Months Ended
Mar. 31, 2021
Fair Value Disclosures [Abstract]
Assets and Liabilities at Fair Value on Recurring BasisThe following tables set forth the Company’s financial assets and liabilities at fair value on a recurring basis as of March 31, 2021 and December 31, 2020 (in thousands):
March 31, 2021
Level 1
Level 2
Level 3
Total
Assets:
Money market funds
$
521,000
$

$

$
521,000
Other current assets
21,695


21,695
Total assets at fair value
$
542,695
$

$

$
542,695
Liabilities:
Other long-term liabilities
(21,695
)


(21,695
)
Total liabilities at fair value
$
(21,695
)
$

$

$
(21,695
)
December 31, 2020
Level 1
Level 2
Level 3
Total
Assets:
Money market funds
$
1,906,000


$
1,906,000
Other current assets
18,423


18,423
Total assets at fair value
$
1,924,423
$

$

$
1,924,423
Liabilities:
Other long-term liabilities
(18,423
)


(18,423
)
Total liabilities at fair value
$
(18,423
)
$

$

$
(18,423
)

Debt Agreements (Tables)

Debt Agreements (Tables)3 Months Ended
Mar. 31, 2021
Debt Disclosure [Abstract]
Outstanding Debt BalancesThe Company’s outstanding debt balances as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands):
March 31, 2021
December 31, 2020
Term Loan Facility due 2028
$
1,600,000

Term Loan Facility due 2026
418,026
418,026
Senior Notes due 2027
600,000
600,000
Total face value
2,618,026
1,018,026
Debt discount
(13,675
)
(10,061
)
Deferred financing fees
(25,834
)
(4,586
)
Total long-term debt
2,578,517
1,003,379
Less: current maturities
16,000

Long-term debt, net of current maturities
$
2,562,517
$
1,003,379

Lease Obligations (Tables)

Lease Obligations (Tables)3 Months Ended
Mar. 31, 2021
Leases [Abstract]
Schedule of Office Space Lease Agreements in Place for Real PropertiesAs of March 31, 2021, the Company had the following office space lease agreements in place for real properties:
Location
Approximate Square Feet
Lease Expiry Date
Dublin, Ireland
18,900
November 4, 2029
Lake Forest, Illinois
160,000
March 31, 2031
Novato, California
61,000
August 31, 2021
South San Francisco, California
20,000
January 31, 2030
Rockville, Maryland (1)
17,300
August 31, 2023 and February 28, 2025
Chicago, Illinois
9,200
December 31, 2028
Gaithersburg, Maryland (1)
7,200
June 30, 2022
Mannheim, Germany
4,800
December 31, 2022
Washington, D.C.
6,000
September 15, 2022
(1)
On March 15, 2021, the Company completed its acquisition of Viela. As part of the acquisition, the Company assumed two leases in Rockville, Maryland for both office and laboratory space and a lease in Gaithersburg, Maryland for office space.
Schedule of Operating Lease Liabilities Recorded on the Balance SheetThe table below reconciles the undiscounted cash flows for each of the first five years and total of the remaining years to the lease liabilities recorded on the Company’s condensed consolidated balance sheet as of March 31, 2021 (in thousands):
2021 (April to December)
$
6,098
2022
7,063
2023
6,595
2024
6,936
2025
6,913
Thereafter
33,063
Total lease payments
66,668
Imputed interest
(18,041
)
Total lease liabilities
$
48,627

Commitments and Contingencies (

Commitments and Contingencies (Tables)3 Months Ended
Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Summary of Remaining Aggregate Potential Milestone Payments Payable Based on Achievement of Net Sales ThresholdsThe remaining aggregate potential milestone payments of $225.0 million are payable based on certain TEPEZZA worldwide net sales thresholds being achieved as noted in the following table:
TEPEZZA Worldwide Net Sales Threshold
Milestone Payment
>$250 million
$50 million
>$375 million
$75 million
>$500 million
$100 million

Share-Based and Long-Term Inc_2

Share-Based and Long-Term Incentive Plans (Tables)3 Months Ended
Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option ActivityThe following table summarizes stock option activity during the three months ended March 31, 2021:
Options
Weighted Average Exercise Price
Weighted Average Contractual Term Remaining (in years)
Aggregate Intrinsic Value (in thousands)
Outstanding as of December 31, 2020
7,129,615
$
21.24
4.60
$
370,073
Assumed in acquisition (1)
1,318,053
41.23
Exercised
(661,780
)
30.06


Forfeited
(268
)
17.19


Expired
(234
)
17.32


Outstanding as of March 31, 2021
7,785,386
23.88
4.82
530,665
Exercisable as of March 31, 2021
6,771,755
$
21.40
4.28
$
478,349
Stock options typically have a contractual term of ten years from grant date.
(1)
On March 15, 2021, the Company completed its acquisition of Viela. Under the terms of the merger agreement for Viela, all outstanding Viela stock options assumed by the Company with vesting dates after June 1, 2021, were converted into stock options to purchase the Company’s ordinary shares. As of March 15, 2021, options previously exercisable for an aggregate of 2,180,159 shares of Viela’s common stock that were converted at a rate of 0.60 to 1 based on the merger agreement, into options to purchase 1,318,053 of the Company’s ordinary shares, were outstanding.
Summary of Restricted Stock Unit ActivityThe following table summarizes restricted stock unit activity for the three months ended March 31, 2021:
Number of Units
Weighted Average Grant-Date Fair Value Per Unit
Outstanding as of December 31, 2020
5,909,120
$
27.87
Granted
1,851,309
73.82
Vested
(2,350,056
)
23.19
Forfeited
(95,177
)
56.21
Outstanding as of March 31, 2021
5,315,196
$
45.44
Summary of Performance Stock Unit Awards (PSUs) ActivityThe following table summarizes performance stock unit awards (“PSUs”) activity for the three months ended March 31, 2021:
Number of Units
Weighted Average Grant-Date Fair Value Per Unit
Average Illiquidity Discount
Recorded Weighted Average Fair Value Per Unit
Outstanding as of December 31, 2020
2,610,924
Granted
450,577
$
93.73
8.64
%
$
85.64
Forfeited
(24,450
)
93.73
9.21
%
85.10
Vested
(2,021,657
)
21.21
2.66
%
20.65
Performance Based Adjustments (1)
512,819
25.42
7.27
%
23.57
Outstanding as of March 31, 2021
1,528,213
(1)
Represents adjustment based on the net sales performance criteria meeting 162.5% of target as of December 31, 2020 for the 2020 PSUs (as defined below), the net sales performance criteria meeting 200.0% of target as of December 31, 2020 for the TEPEZZA PSUs (as defined below) and meeting total shareholder return (“TSR”) performance at 200.0% for the PSUs that were awarded to key executive participants on January 5, 2018.
Summary of Significant Valuation Assumptions Related to 2020 PSUsAll PSUs outstanding at March 31, 2021 may vest in a range of between 0% and 200%, with the exception of the modified KRYSTEXXA 2020 Net Sales PSUs which are capped at 150%, based on the performance metrics described above. The Company accounts for the 2020 PSUs and 2021 PSUs as equity-settled awards in accordance with ASC 718. Because the value of the 2020 Relative TSR PSUs and 2021 Relative TSR PSUs are dependent upon the attainment of a level of TSR, it requires the impact of the market condition to be considered when estimating the fair value of the 2020 Relative TSR PSUs and 2021 Relative TSR PSUs. As a result, the Monte Carlo model is applied and the most significant valuation assumptions used related to the 2021 PSUs during the three months ended March 31, 2021, include:
Valuation date stock price
$
72.54
Expected volatility
45.8
%
Risk free rate
0.2
%
Summary of Share-Based Compensation ExpenseThe following table summarizes share-based compensation expense included in the Company’s condensed consolidated statements of operations for the three months ended March 31, 2021 and 2020 (in thousands):
For the Three Months Ended March 31,
2021
2020
Share-based compensation expense
Cost of goods sold
$
1,936
$
2,689
Research and development
5,616
6,376
Selling, general and administrative
53,614
47,356
Total share-based compensation expense
$
61,166
$
56,421

Income Taxes (Tables)

Income Taxes (Tables)3 Months Ended
Mar. 31, 2021
Income Tax Disclosure [Abstract]
Benefit for Income TaxesThe following table presents the benefit for income taxes for the three months ended March 31, 2021 and 2020 (in thousands):
For
2021
2020
Loss before benefit for income taxes
$
(171,102
)
$
(32,617
)
Benefit for income taxes
(47,751
)
(19,026
)
Net loss
$
(123,351
)
$
(13,591
)

Basis of Presentation and Bus_2

Basis of Presentation and Business Overview - Additional Information (Detail) $ / shares in Units, $ in ThousandsMar. 15, 2021USD ($)$ / sharesMar. 31, 2021USD ($)Segment
Basis Of Presentation [Line Items]
Number of reportable segments | Segment2
Viela Bio [Member]
Basis Of Presentation [Line Items]
Business Acquisition, Date of Acquisition AgreementMar. 15,
2021
Total consideration for acquisition $ 3,000,000 $ 2,994,091
Cash acquired from acquisition $ 342,300 $ 342,300
Ordinary Shares [Member] | Viela Bio [Member]
Basis Of Presentation [Line Items]
Share price | $ / shares $ 53

Net Loss per Share - Basic and

Net Loss per Share - Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Basic and diluted net loss per share calculation:
Numerator - net loss $ (123,351) $ (13,591)
Weighted average ordinary shares outstanding—basic and diluted223,920,768 190,072,112
Basic and diluted net loss per share $ (0.55) $ (0.07)

Net Loss per Share - Additional

Net Loss per Share - Additional Information (Detail) - shares shares in Millions3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Exchangeable Senior Notes [Member]
Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share14
Interest rate2.50%
Equity Awards [Member]
Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share13.4 9.3

Acquisitions, Divestitures an_3

Acquisitions, Divestitures and Other Arrangements - Additional Information (Detail)Mar. 15, 2021USD ($)$ / sharesNov. 21, 2020USD ($)May 08, 2017USD ($)Feb. 28, 2021USD ($)Apr. 30, 2020USD ($)Jul. 31, 2019USD ($)Mar. 31, 2021USD ($)$ / shares$ / SFrMar. 31, 2021CHF (SFr)Dec. 31, 2020USD ($)Jun. 30, 2020USD ($)Mar. 31, 2020USD ($)$ / SFrMar. 31, 2020CHF (SFr)Dec. 31, 2020USD ($)Mar. 31, 2021CHF (SFr)$ / SFrDec. 31, 2020CHF (SFr)Oct. 27, 2020USD ($)Jan. 01, 2020USD ($)Jan. 03, 2019USD ($)
Business Acquisition [Line Items]
Inventories, net $ 238,306,000 $ 75,283,000 $ 75,283,000
Upfront cash payments $ 3,000,000 $ 3,000,000
Developed technology and other intangible assets, net3,210,221,000 1,782,962,000 1,782,962,000
Payment to be made upon attainment of milestones67,000,000 67,000,000
Upfront cash payments30,000,000
River Vision [Member]
Business Acquisition [Line Items]
Developed technology and other intangible assets, net $ 110,000,000
Milestone And Royalty Payments $ 55,000,000
Roche [Member]
Business Acquisition [Line Items]
Net sales109,200,000 SFr 103,000,000
Milestone incurred $ 5,200,000 SFr 5,000,000 $ 5,200,000 SFr 5,000,000
Currency exchange rate | $ / SFr1.0382 1.0382 1.0382
TEPEZZA [Member]
Business Acquisition [Line Items]
Developed technology and other intangible assets, net120,800,000 120,800,000
Viela Bio [Member]
Business Acquisition [Line Items]
Share price | $ / shares $ 53
Cash and cash equivalents, at carrying value $ 1,600,000,000
Total consideration for acquisition3,000,000,000 $ 2,994,091,000
Cash acquired from acquisition $ 342,300,000 342,300,000
Acquisition-related costs $ 28,000,000
Acquisition-date fair value at a discount rate11.50%11.50%
Finite-lived intangible assets, remaining amortization period14 years14 years
Deferred tax liability rate24.10%24.10%
Deferred tax liability $ 457,928,000
Business Acquisition, Date of Acquisition AgreementMar. 15,
2021
Viela Bio [Member] | Research and Development Expense [Member]
Business Acquisition [Line Items]
Acquisition-date fair value at a discount rate12.50%12.50%
Viela Bio [Member] | Ordinary Shares [Member]
Business Acquisition [Line Items]
Share price | $ / shares $ 53
UPLIZNA [Member]
Business Acquisition [Line Items]
Inventory, raw materials $ 10,100,000
Inventory, work in Process, gross119,000,000
Inventories, net149,300,000
Inventory, finished goods, gross20,200,000
Inventory adjustments900,000
Curzion Pharmaceuticals Inc [Member]
Business Acquisition [Line Items]
Transaction costs $ 86,100,000
Upfront cash payment45,000,000
RAVICTI and BUPHENYL [Member]
Business Acquisition [Line Items]
Net sales $ 5,400,000
Net loss4,900,000
River Vision [Member]
Business Acquisition [Line Items]
Cash acquired from acquisition $ 6,300,000
Net sales325,000,000 $ 325,000,000
Percentage of equity interests acquired100.00%
Business Acquisition, Date of Acquisition AgreementMay 8,
2017
Upfront cash payments $ 150,300,000
Percentage of net sales in earn-out payment3.00%3.00%
Net sales minimum limit for royal payment $ 300,000,000
Payment to be made upon attainment of milestones $ 53,800,000 53,800,000 SFr 50,000,000
River Vision [Member] | U.S. Food and Drug Administration (FDA) Approval [Member]
Business Acquisition [Line Items]
Net sales100,000,000
River Vision [Member] | Net Sales Thresholds [Member] | Teprotumumab [Member]
Business Acquisition [Line Items]
Net sales $ 225,000,000 $ 225,000,000
Halozyme [Member]
Business Acquisition [Line Items]
Upfront cash payments $ 30,000,000
Potential additional contingent consideration payment $ 160,000,000
HemoShear [Member]
Business Acquisition [Line Items]
Upfront cash payment $ 2,000,000
Business combination progress payments paid under collaboration agreement. $ 4,000,000

Acquisitions, Divestitures an_4

Acquisitions, Divestitures and Other Arrangements - Schedule of Total Consideration for the Acquisitions (Detail) - Viela Bio [Member] - USD ($) $ in ThousandsMar. 15, 2021Mar. 31, 2021
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Equity value (54,988,820 shares at $53.00 per share) $ 2,914,407
Net settlements on the exercise of stock options78,554
Consideration for exchange of Viela stock options1,130
Total consideration $ 3,000,000 $ 2,994,091

Acquisitions, Divestitures an_5

Acquisitions, Divestitures and Other Arrangements - Schedule of Total Consideration for the Acquisitions ((Parenthetical) (Detail) - Viela Bio [Member]3 Months Ended
Mar. 31, 2021$ / sharesshares
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Equity value, shares | shares54,988,820
Share price | $ / shares $ 53

Acquisitions, Divestitures an_6

Acquisitions, Divestitures and Other Arrangements - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Goodwill $ 1,076,388 $ 413,669
Viela Bio [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Deferred tax liabilities, net(457,928)
Accrued expenses(73,401)
Other long-term liabilities(22,631)
Accounts payable(4,768)
Accrued trade discounts and rebates(1,492)
Marketable securities400
Property, plant and equipment1,747
Other assets3,253
Accounts receivable8,053
Prepaid expenses and other current assets16,444
Inventories149,348
Cash and cash equivalents342,347
In-process research and development910,000
Developed technology1,460,000
(Liabilities assumed) and assets acquired2,331,372
Goodwill662,719
Fair value of consideration paid $ 2,994,091

Acquisitions, Divestitures an_7

Acquisitions, Divestitures and Other Arrangements - Gain (Loss) on Sale of Assets (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Pro forma adjustments [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net sales $ 10,588
Net loss(43,556) $ (120,002)
Pro forma [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net sales352,994 355,909
Net loss(166,907)(133,593)
As reported [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net sales342,406 355,909
Net loss $ (123,351) $ (13,591)

Inventories - Components of Inv

Inventories - Components of Inventories (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials $ 29,861 $ 11,760
Work-in-process140,813 33,167
Finished goods67,632 30,356
Inventories, net $ 238,306 $ 75,283

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Dec. 31, 2020
Inventory [Line Items]
Raw materials $ 29,861 $ 11,760
Work-in-process140,813 33,167
Finished goods67,632 $ 30,356
UPLIZNA [Member]
Inventory [Line Items]
Raw materials10,100
Work-in-process119,000
Finished goods19,300
Inventory set-up expense $ 900

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Advance payments for inventory $ 167,753 $ 137,680
Deferred charge for taxes on intercompany profit58,617 52,306
Prepaid income taxes and income tax receivable23,456 102
Rabbi trust assets21,709 18,423
Other prepaid expenses and other current assets62,907 43,434
Prepaid expenses and other current assets $ 334,442 $ 251,945

Property and Equipment - Proper

Property and Equipment - Property and Equipment (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross $ 232,407 $ 236,828
Less accumulated depreciation(30,550)(47,791)
Property and equipment, net201,857 189,037
Building [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross128,268 80,341
Land and Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross38,880 38,076
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross9,558 26,323
Software [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross14,487 14,618
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross16,910 4,695
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross12,017 5,973
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross7,370 63,656
Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross $ 4,917 $ 3,146

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) $ in Thousands1 Months Ended3 Months Ended
Feb. 26, 2020USD ($)BuildingMar. 31, 2021USD ($)Mar. 31, 2020USD ($)Feb. 26, 2020aFeb. 26, 2020ft²
Property, Plant and Equipment [Line Items]
Depreciation expense $ 4,451 $ 7,165
Deerfield, Illinois [Member]
Property, Plant and Equipment [Line Items]
Purchase of building for consideration and transaction costs $ 118,500
Number of building purchased | Building3
Office space70 650,000

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)Mar. 15, 2021Mar. 31, 2021Mar. 31, 2020Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Goodwill, gross $ 1,076,400,000 $ 413,700,000
Acquired during the period662,719,000
Accumulated goodwill impairment losses0
Amortization expense of developed technology66,369,000 $ 58,575,000
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Capitalized payments of intangible assets $ 1,460,000,000
Developed Technology [Member] | TEPEZZA [Member]
Finite-Lived Intangible Assets [Line Items]
Capitalized payments of intangible assets $ 336,000,000
Viela [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired during the period662,700,000
Capitalized payments of intangible assets $ 880,000,000

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Goodwill for Reportable Segments (Detail) $ in Thousands3 Months Ended
Mar. 31, 2021USD ($)
Goodwill [Line Items]
Goodwill, beginning balance $ 413,669
Acquired during the period662,719
Goodwill, ending balance1,076,388
Orphan [Member]
Goodwill [Line Items]
Goodwill, beginning balance357,498
Acquired during the period662,719
Goodwill, ending balance1,020,217
Inflammation [Member]
Goodwill [Line Items]
Goodwill, beginning balance56,171
Goodwill, ending balance $ 56,171

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Amortizable Intangible Assets (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Cost Basis $ 5,475,615 $ 3,101,986
Accumulated Amortization(1,385,394)(1,319,024)
Net Book Value4,090,221 1,782,962
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Cost Basis4,587,515 3,093,886
Accumulated Amortization(1,380,104)(1,313,934)
Net Book Value3,207,411 1,779,952
In Process Research and Development [Member]
Finite-Lived Intangible Assets [Line Items]
Cost Basis[1]880,000
Net Book Value[1]880,000
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Cost Basis8,100 8,100
Accumulated Amortization(5,290)(5,090)
Net Book Value $ 2,810 $ 3,010
[1]The Company acquired IPR&D of $910.0 million relating to Viela. On March 24, 2021, the Company announced that its strategic partner, Mitsubishi Tanabe Pharma Corporation, had received manufacturing and marketing approval of UPLIZNA in Japan. As a result, the Company transferred $30.0 million of IPR&D to developed technology. As of March 31, 2021, the remaining IPR&D relating to the Viela acquisition was $880.0 million.

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Amortizable Intangible Assets - (Parenthetical) (Detail) - USD ($) $ in MillionsMar. 24, 2021Mar. 15, 2021Mar. 31, 2021
Viela [Member]
Finite-Lived Intangible Assets [Line Items]
Capitalized payments of intangible assets $ 880
IPR&D [Member] | Viela [Member]
Finite-Lived Intangible Assets [Line Items]
Capitalized payments of intangible assets $ 910
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Capitalized payments of intangible assets $ 1,460
Developed Technology [Member] | Viela [Member]
Finite-Lived Intangible Assets [Line Items]
Total consideration for acquisition $ 30

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets - Estimated Future Amortization Expense (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
2021 (April to December) $ 268,242
2022355,047
2023354,582
2024353,102
2025350,861
Thereafter1,528,387
Total $ 3,210,221 $ 1,782,962

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Payables And Accruals [Abstract]
Payroll-related expenses $ 72,906 $ 121,577
Accrued milestone payments69,962 123,442
Consulting and professional services50,635 21,893
Allowances for returns38,089 40,918
R&D and manufacturing programs31,376 17,289
Accrued royalties23,839 68,006
Advertising and marketing17,468 12,428
Pricing review liability17,169 16,046
Accrued interest7,784 14,207
Accrued other60,398 49,761
Accrued expenses $ 389,626 $ 485,567

Accrued Trade Discounts and R_3

Accrued Trade Discounts and Rebates - Schedule of Accrued Trade Discounts and Rebates (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Accrued Commercial Rebates and Wholesaler Fees [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Total customer-related accruals and allowances $ 67,025 $ 82,646
Accrued Co-Pay and Other Patient Assistance [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Total customer-related accruals and allowances80,449 96,924
Accrued Government Rebates and Chargebacks [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Total customer-related accruals and allowances177,758 172,893
Accrued Trade Discounts and Rebates [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Total customer-related accruals and allowances325,232 352,463
Invoiced Commercial Rebates and Wholesaler Fees, Co pay and Other Patient Assistance Costs, and Government Rebates and Chargebacks in Accounts Payable [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Total customer-related accruals and allowances2,608 1,452
Customer-related Accruals and Allowances [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Total customer-related accruals and allowances $ 327,840 $ 353,915

Accrued Trade Discounts and R_4

Accrued Trade Discounts and Rebates - Schedule of Customer-Related Accruals and Allowances (Detail) $ in Thousands3 Months Ended
Mar. 31, 2021USD ($)
Government Rebates and Chargebacks [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance $ 172,893
Current provisions relating to sales146,491
Adjustments relating to prior-year sales(3,716)
Payments relating to sales(31,764)
Payments relating to prior-year sales(107,557)
Ending Balance177,758
Government Rebates and Chargebacks [Member] | Viela [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Viela acquisition1,411
Co-Pay and Other Patient Assistance [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance96,924
Current provisions relating to sales199,031
Adjustments relating to prior-year sales(52)
Payments relating to sales(124,234)
Payments relating to prior-year sales(90,728)
Ending Balance80,952
Co-Pay and Other Patient Assistance [Member] | Viela [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Viela acquisition11
Wholesaler Fees and Commercial Rebates [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance84,098
Current provisions relating to sales63,971
Adjustments relating to prior-year sales(758)
Payments relating to sales(10,799)
Payments relating to prior-year sales(67,452)
Ending Balance69,130
Wholesaler Fees and Commercial Rebates [Member] | Viela [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Viela acquisition70
Customer-related Accruals and Allowances [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance353,915
Current provisions relating to sales409,493
Adjustments relating to prior-year sales(4,526)
Payments relating to sales(166,797)
Payments relating to prior-year sales(265,737)
Ending Balance327,840
Customer-related Accruals and Allowances [Member] | Viela [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Viela acquisition $ 1,492

Segment and Other Information -

Segment and Other Information - Additional Information (Detail) - Segment3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Segment Reporting Information [Line Items]
Number of reportable segments2
Customer Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Consolidated receivable/sales percentage to major customers100.00%100.00%
Customer Concentration Risk [Member] | Sales Revenue [Member] | Minimum [Member]
Segment Reporting Information [Line Items]
Consolidated receivable/sales percentage to major customers10.00%

Segment and Other Information_2

Segment and Other Information - Summary of Net Sales by Medicine for Reportable Segments (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Segment Reporting Information [Line Items]
Total net sales $ 342,406 $ 355,909
RAVICTI [Member]
Segment Reporting Information [Line Items]
Total net sales72,817 61,189
KRYSTEXXA [Member]
Segment Reporting Information [Line Items]
Total net sales106,757 93,248
PROCYSBI [Member]
Segment Reporting Information [Line Items]
Total net sales43,363 38,343
ACTIMMUNE [Member]
Segment Reporting Information [Line Items]
Total net sales28,763 26,541
TEPEZZA [Member]
Segment Reporting Information [Line Items]
Total net sales2,065 23,452
RAYOS [Member]
Segment Reporting Information [Line Items]
Total net sales15,272 18,209
UPLIZNA [Member]
Segment Reporting Information [Line Items]
Total net sales1,873
BUPHENYL [Member]
Segment Reporting Information [Line Items]
Total net sales1,660 2,313
QUINSAIR [Member]
Segment Reporting Information [Line Items]
Total net sales209 277
Orphan Segment Net Sales [Member]
Segment Reporting Information [Line Items]
Total net sales257,507 245,363
PENNSAID 2% [Member]
Segment Reporting Information [Line Items]
Total net sales45,817 41,563
DUEXIS [Member]
Segment Reporting Information [Line Items]
Total net sales19,465 31,346
VIMOVO [Member]
Segment Reporting Information [Line Items]
Total net sales4,345 19,428
Inflammation [Member]
Segment Reporting Information [Line Items]
Total net sales $ 84,899 $ 110,546

Segment and Other Information_3

Segment and Other Information - Summary of Reconciliations of Segment Operating Income (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Segment operating income:
Operating income $ (160,018) $ (16,491)
Amortization and step-up:
Intangible amortization expense(66,369)(58,575)
Inventory step-up expense(911)
Share-based compensation(61,166)(56,421)
Acquisition/divestiture-related costs(49,391)(284)
Interest expense, net(13,460)(17,344)
Impairment of long-lived assets(12,371)
Depreciation(4,451)(7,165)
Restructuring and realignment costs(6,093)
Upfront, progress and milestone payments related to license and collaboration agreements(3,000)
Foreign exchange (loss) gain(848)776
Drug substance harmonization costs(290)
Fees related to refinancing activities(54)
Other income, net3,224 442
Loss before benefit for income taxes(171,102)(32,617)
Orphan [Member]
Segment operating income:
Operating income1,054 54,356
Inflammation [Member]
Segment operating income:
Operating income $ 42,680 $ 51,942

Segment and Other Information_4

Segment and Other Information - Schedule of Gross Sales to Customers Included in Reportable Segments and All Other Customers as a Group (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Segment Reporting Information [Line Items]
Gross Sales, Amount $ 761,532 $ 803,522
Customer Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Gross Sales, Percentage100.00%100.00%
Customer A [Member]
Segment Reporting Information [Line Items]
Gross Sales, Amount $ 248,740 $ 246,775
Customer A [Member] | Customer Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Gross Sales, Percentage33.00%31.00%
Customer B [Member]
Segment Reporting Information [Line Items]
Gross Sales, Amount $ 184,687 $ 207,277
Customer B [Member] | Customer Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Gross Sales, Percentage24.00%26.00%
Customer C [Member]
Segment Reporting Information [Line Items]
Gross Sales, Amount $ 118,037 $ 133,876
Customer C [Member] | Customer Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Gross Sales, Percentage15.00%17.00%
Customer D [Member]
Segment Reporting Information [Line Items]
Gross Sales, Amount $ 90,619 $ 84,788
Customer D [Member] | Customer Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Gross Sales, Percentage12.00%10.00%
Other Customers [Member]
Segment Reporting Information [Line Items]
Gross Sales, Amount $ 119,449 $ 130,806
Other Customers [Member] | Customer Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Gross Sales, Percentage16.00%16.00%

Segment and Other Information_5

Segment and Other Information - Summary of Net Sales Attributed to Geographic Sources (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Segment Reporting Information [Line Items]
Total net sales $ 342,406 $ 355,909
United States [Member]
Segment Reporting Information [Line Items]
Total net sales $ 340,330 $ 354,016
United States [Member] | Geographic Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Total Net Sales, Percentage99.00%100.00%
Rest of World [Member]
Segment Reporting Information [Line Items]
Total net sales $ 2,076 $ 1,893
Rest of World [Member] | Geographic Concentration Risk [Member] | Sales Revenue [Member]
Segment Reporting Information [Line Items]
Total Net Sales, Percentage1.00%

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities at Fair Value on Recurring Basis (Detail) - Fair Value Measurements, Recurring Basis [Member] - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value $ 542,695 $ 1,924,423
Total liabilities at fair value(21,695)(18,423)
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value521,000 1,906,000
Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value21,695 18,423
Other Long-term Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities at fair value(21,695)(18,423)
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value542,695 1,924,423
Total liabilities at fair value(21,695)(18,423)
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value521,000 1,906,000
Level 1 [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value21,695 18,423
Level 1 [Member] | Other Long-term Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities at fair value $ (21,695) $ (18,423)

Debt Agreements - Outstanding D

Debt Agreements - Outstanding Debt Balances (Detail) - USD ($) $ in ThousandsMar. 31, 2021Dec. 31, 2020Jul. 16, 2019
Debt Instrument [Line Items]
Total face value $ 2,618,026 $ 1,018,026 $ 625,000
Debt discount(13,675)(10,061)
Deferred financing fees(25,834)(4,586)
Total long-term debt2,578,517 1,003,379
Less: current maturities16,000
Long-term debt, net of current maturities2,562,517 1,003,379
Term Loan Facility due 2028 [Member]
Debt Instrument [Line Items]
Total face value1,600,000
Term Loan Facility due 2026 [Member]
Debt Instrument [Line Items]
Total face value418,026 418,026
Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Total face value $ 600,000 $ 600,000

Debt Agreements - Term Loan Fac

Debt Agreements - Term Loan Facility and Revolving Credit Facility - Additional Information (Detail) - USD ($)Sep. 15, 2021Dec. 18, 2019Mar. 11, 2019Mar. 31, 2020Mar. 31, 2021Mar. 15, 2021Dec. 31, 2019
Refinancing Loans
Debt Instrument [Line Items]
LIBOR floor rate0.50%
Debt instrument variable rate2.00%
Interest rate descriptionThe Incremental Loans were incurred as a separate class of term loans under the Credit Agreement with substantially the same terms of the December 2019 Refinancing Loans.  The Borrower used the proceeds of the Incremental Loans to fund a portion of the consideration payable in the acquisition of Viela.  The Incremental Loans bear interest at a rate, at Borrower’s option, equal to the London Inter-Bank Offered Rate (“LIBOR”), plus 2.00% per annum (subject to a 0.50% LIBOR floor) or the adjusted base rate plus 1.00% per annum, with a step-down to LIBOR plus 1.75% per annum or the adjusted base rate plus 0.75% per annum at the time the Company’s leverage ratio is less than or equal to 2.00 to 1.00.  The adjusted base rate is defined as the greatest of (a) LIBOR (using one-month interest period) plus 1.00%, (b) the prime rate, (c) the federal funds rate plus 0.50%, and (d) 1.00%.
Repayment of refinanced loans, amount $ 418,000,000
Debt instrument, variable interest rate2.13%
Debt instrument, effective interest rate2.42%
Refinancing Loans | Scenario, Plan
Debt Instrument [Line Items]
Debt instrument variable rate1.75%
Refinancing Loans | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument leverage ratio2.00%
Refinancing Loans | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument leverage ratio1.00%
Refinancing Loans | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument variable rate1.00%
Refinancing Loans | London Interbank Offered Rate (LIBOR) | Scenario, Plan
Debt Instrument [Line Items]
Debt instrument variable rate0.75%
2019 Term Loan Facility [Member]
Debt Instrument [Line Items]
LIBOR floor rate0.00%
Debt instrument variable rate2.25%
Interest rate descriptionThe December 2019 Refinancing Loans were incurred as a separate new class of term loans under the Credit Agreement with substantially the same terms as the previously outstanding senior secured term loans incurred on May 22, 2019 (the “Refinanced Loans”) to effectuate a repricing of the Refinanced Loans.  The Borrower used the proceeds of the December 2019 Refinancing Loans to repay the Refinanced Loans, which totaled approximately $418.0 million.  The December 2019 Refinancing Loans bear interest at a rate, at the Borrower’s option, equal to LIBOR plus 2.25% per annum (subject to a 0.00% LIBOR floor) or the adjusted base rate plus 1.25% per annum, with a step-down to LIBOR plus 2.00% per annum or the adjusted base rate plus 1.00% per annum at the time the Company’s leverage ratio is less than or equal to 2.00 to 1.00
Percent Of Premium On Repayment Of Debt1.00%
Proceeds from debt issuances, percentage on excess cash flow50.00%
Proceeds from debt issuances, reduction percentage on excess cash flow25.00%
Proceeds from debt issuances, percentage on first lien leverage ratio0.00%
Credit agreement, descriptionThe Borrower is permitted to make voluntary prepayments of the loans under the Credit Agreement at any time without payment of a premium, except that with respect to the Incremental Loans, a 1% premium will apply to a repayment of the Incremental Loans in connection with a repricing of, or any amendment to the Credit Agreement in a repricing of, such loans effected on or prior to September 15, 2021.  The Borrower is required to make mandatory prepayments of loans under the Credit Agreement (without payment of a premium) with (a) net cash proceeds from certain non-ordinary course asset sales (subject to reinvestment rights and other exceptions), (b) casualty proceeds and condemnation awards (subject to reinvestment rights and other exceptions), (c) net cash proceeds from issuances of debt (other than certain permitted debt), and (d) 50% of the Company’s excess cash flow (subject to decrease to 25% or 0% if the Company’s first lien leverage ratio is less than 2.25:1 or 1.75:1, respectively).  The Incremental Loans will amortize in equal quarterly installments in an aggregate annual amount equal to 1% of the original principal amount thereof, with any remaining balance payable on March 15, 2028, the final maturity date of the Incremental Loans.  The principal amount of the December 2019 Refinancing Loans are due and payable on May 22, 2026, the final maturity date of the December 2019 Refinancing Loans.  
Maturity date of debt instrumentMay 22,
2026
2019 Term Loan Facility [Member] | Horizon Pharma Subsidiaries [Member]
Debt Instrument [Line Items]
Cut off percentage for defining limited liability subsidiaries, portion of capital stock held maximum65.00%
2019 Term Loan Facility [Member] | Scenario, Plan
Debt Instrument [Line Items]
Debt instrument variable rate2.00%
2019 Term Loan Facility [Member] | Scenario Forecast
Debt Instrument [Line Items]
Percent Of Premium On Repayment Of Debt1.00%
Percentage of debt instrument amortization of principal amount1.00%
2019 Term Loan Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument leverage ratio2.00%
Leverage ratio less than applicable margin1.00%
First lien leverage ratio175.00%
2019 Term Loan Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument leverage ratio1.00%
Leverage ratio less than applicable margin2.00%
First lien leverage ratio225.00%
2019 Term Loan Facility [Member] | Adjusted Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument variable rate1.25%
2019 Term Loan Facility [Member] | Adjusted Base Rate [Member] | Scenario, Plan
Debt Instrument [Line Items]
Debt instrument variable rate1.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
LIBOR floor rate0.00%
Interest rate descriptionThe loans under the Revolving Credit Facility bear interest, at the Borrower’s option, at a rate equal to either LIBOR plus an applicable margin of 2.25% per annum (subject to a LIBOR floor of 0.00%), or the adjusted base rate plus 1.25% per annum, with a step-down to LIBOR plus 2.00% per annum or the adjusted base rate plus 1.00% per annum at the time the Company’s leverage ratio is less than or equal to 2.00 to 1.00.
Minimum percentage of total commitments25.00%
Revolving Credit Facility [Member] | Adjusted Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument variable rate1.25%
Revolving Credit Facility [Member] | Adjusted Base Rate [Member] | Scenario, Plan
Debt Instrument [Line Items]
Debt instrument variable rate1.00%
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument variable rate2.25%
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) | Scenario, Plan
Debt Instrument [Line Items]
Debt instrument variable rate2.00%
Term Loan Facility [Member]
Debt Instrument [Line Items]
Debt instrument, variable interest rate2.50%
Debt instrument, effective interest rate2.76%
Horizon Pharma USA Inc [Member] | New Incremental Revolving Commitments [Member]
Debt Instrument [Line Items]
Line of credit facility borrowing capacity $ 1,600,000,000
Aggregate principal amount $ 200,000,000
Line of credit facility additional borrowing capacity $ 275,000,000
Line of credit facility termination period2024-03
Horizon Pharma USA Inc [Member] | May 2019 Refinancing Loans [Member]
Debt Instrument [Line Items]
Line of credit facility borrowing capacity $ 418,000,000
Horizon Pharma USA Inc [Member] | Letter of Credit Sub-facility [Member]
Debt Instrument [Line Items]
Line of credit facility additional borrowing capacity $ 50,000,000
Hyperion Therapeutics, Inc. [Member] | Refinancing Loans | Underwritten Public Offering
Debt Instrument [Line Items]
Debt instrument, fair value $ 415,900,000
Hyperion Therapeutics, Inc. [Member] | Term Loan Facility [Member] | Underwritten Public Offering
Debt Instrument [Line Items]
Debt instrument, fair value $ 1,596,000,000

Debt Agreements - 2027 Senior N

Debt Agreements - 2027 Senior Notes - Additional Information (Detail) - USD ($) $ in ThousandsJul. 16, 2019Mar. 31, 2020Mar. 31, 2021Dec. 31, 2020
Debt Instrument [Line Items]
Senior notes $ 2,562,517 $ 1,003,379
Outstanding principal amount $ 625,000 $ 2,618,026 $ 1,018,026
Senior Secured Term Loan [Member]
Debt Instrument [Line Items]
Outstanding principal amount $ 100,000
2027 Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate5.50%5.50%
Cash on hand $ 65,000
Debt instrument, frequency of periodic paymentsemiannually
Debt instrument redemption descriptionthe 2027 Senior Notes may be redeemed at any time at specified redemption prices, plus accrued and unpaid interest to the redemption date.  At any time prior to August 1, 2022, some or all of the 2027 Senior Notes may be redeemed at a price equal to 100% of the aggregate principal amount thereof, plus a make-whole premium and accrued and unpaid interest to the redemption date.  Also prior to August 1, 2022, up to 40% of the aggregate principal amount of the 2027 Senior Notes may be redeemed at a redemption price of 105.5% of the aggregate principal amount thereof, plus accrued and unpaid interest, with the net proceeds of certain equity offerings.  In addition, the 2027 Senior Notes may be redeemed in whole but not in part at a redemption price equal to 100% of the principal amount plus accrued and unpaid interest and additional amounts, if any, to, but excluding, the redemption date, if on the next date on which any amount would be payable in respect of the 2027 Senior Notes, HTUSA or any guarantor is or would be required to pay additional amounts as a result of certain tax related events.
Debt instrument, effective interest rate5.76%
Debt instrument, fair value $ 640,500
2027 Senior Notes [Member] | Prior to August 1, 2022 [Member]
Debt Instrument [Line Items]
Redemption price as percentage of aggregate principal amount105.50%
2027 Senior Notes [Member] | Prior to August 1, 2022 [Member] | Maximum [Member]
Debt Instrument [Line Items]
Redemption amount as percentage of aggregate principal amount40.00%
2027 Senior Notes [Member] | Prior to August 1, 2022, Some or All of Aggregate Principal Amount [Member]
Debt Instrument [Line Items]
Redemption price as percentage of aggregate principal amount100.00%
2027 Senior Notes [Member] | After August 1, 2022, in Whole But Not in Part [Member]
Debt Instrument [Line Items]
Redemption price as percentage of aggregate principal amount100.00%
2023 Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate6.625%
Outstanding principal amount $ 225,000
2024 Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate8.75%
Outstanding principal amount $ 300,000
Horizon Pharma USA Inc [Member] | 2027 Senior Notes [Member]
Debt Instrument [Line Items]
Senior notes $ 600,000
Interest rate5.50%
Maturity date of debt instrumentAug. 1,
2027
Debt instrument redemption descriptionIf the Company undergoes a change of control, HTUSA will be required to make an offer to purchase all of the 2027 Senior Notes at a price in cash equal to 101% of the aggregate principal amount thereof plus accrued and unpaid interest to, but not including, the repurchase date, subject to certain exceptions.  If the Company or certain of its subsidiaries engages in certain asset sales, HTUSA will be required under certain circumstances to make an offer to purchase the 2027 Senior Notes at 100% of the principal amount thereof, plus accrued and unpaid interest to the repurchase date.
Redemption price percentage of principal amount of debt instrument on change of control101.00%

Lease Obligations - Schedule of

Lease Obligations - Schedule of Office Space Lease Agreements in Place for Real Properties (Detail) - ft²3 Months Ended
Mar. 31, 2021Oct. 14, 2019
Dublin Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet18,900 63,000
Lease Expiry DateNov. 4,
2029
Lake Forest Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet160,000
Lease Expiry DateMar. 31,
2031
Novato Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet61,000
Lease Expiry DateAug. 31,
2021
South San Francisco Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet20,000
Lease Expiry DateJan. 31,
2030
Rockville Maryland Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet17,300
Rockville Maryland Office [Member] | Minimum [Member]
Lessee Lease Description [Line Items]
Lease Expiry DateAug. 31,
2023
Rockville Maryland Office [Member] | Maximum [Member]
Lessee Lease Description [Line Items]
Lease Expiry DateFeb. 28,
2025
Chicago Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet9,200
Lease Expiry DateDec. 31,
2028
Gaithersburg Maryland Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet7,200
Lease Expiry DateJun. 30,
2022
Mannheim Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet4,800
Lease Expiry DateDec. 31,
2022
Washington, D.C. Office [Member]
Lessee Lease Description [Line Items]
Approximate Square Feet6,000
Lease Expiry DateSep. 15,
2022

Lease Obligations - Additional

Lease Obligations - Additional Information (Detail) $ in Thousands3 Months Ended
Mar. 31, 2021USD ($)ft²Mar. 31, 2020USD ($)Dec. 31, 2020USD ($)Oct. 14, 2019ft²
Lessee Lease Description [Line Items]
Number of leases $ 2
Right-of-use assets $ 24,200 $ 34,400
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]Other assetsOther assets
Lease liability, current $ 4,700 $ 4,100
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]Accrued expensesAccrued expenses
Lease liability, noncurrent $ 43,900 $ 43,200
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]Other long-term liabilitiesOther long-term liabilities
Rent expense $ 1,600 $ 1,600
Weighted-average discount rate7.03%
Weighted-average remaining lease term9 years 3 months 21 days
Dublin Office [Member]
Lessee Lease Description [Line Items]
Approximate square feet of office space | ft²18,900 63,000
Lake Forest Office [Member]
Lessee Lease Description [Line Items]
Approximate square feet of office space | ft²160,000
Impairment charges $ 12,400

Lease Obligations - Schedule _2

Lease Obligations - Schedule of Operating Lease Liabilities Recorded on the Balance Sheet (Detail) $ in ThousandsMar. 31, 2021USD ($)
Leases [Abstract]
Operating Lease liabilities, 2021 (April to December) $ 6,098
Operating Lease liabilities, 20227,063
Operating Lease liabilities, 20236,595
Operating Lease liabilities, 20246,936
Operating Lease liabilities, 20256,913
Operating Lease liabilities, Thereafter33,063
Operating Lease liabilities,Total lease payments66,668
Operating Lease liabilities, Imputed interest(18,041)
Total lease liabilities $ 48,627

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) € in MillionsMay 08, 2017USD ($)Feb. 28, 2021USD ($)$ / SFrFeb. 28, 2021CHF (SFr)$ / SFrApr. 30, 2020Mar. 31, 2021USD ($)$ / SFr$ / €Mar. 31, 2021CHF (SFr)Mar. 31, 2021EUR (€)Jun. 30, 2020USD ($)Mar. 31, 2020USD ($)$ / SFrMar. 31, 2020CHF (SFr)Dec. 31, 2020USD ($)Mar. 31, 2021CHF (SFr)$ / SFr$ / €Dec. 31, 2020CHF (SFr)Apr. 01, 2020USD ($)
Loss Contingencies [Line Items]
Upfront cash payments $ 3,000,000 $ 3,000,000
Payment to be made upon attainment of milestones $ 67,000,000
Amount committed in investment $ 51,700,000
Net cash payments for investment3,800,000
Other Income, Net [Member]
Loss Contingencies [Line Items]
Investment income2,900,000
Other Assets [Member]
Loss Contingencies [Line Items]
Amount committed in investment17,500,000
TEPEZZA [Member]
Loss Contingencies [Line Items]
Payment to be made upon attainment of milestones123,400,000
Upfront cash payment30,000,000
Future milestone payments160,000,000
River Vision [Member]
Loss Contingencies [Line Items]
Net sales325,000,000 $ 325,000,000
Upfront cash payments $ 150,300,000
Percentage of net sales in earn-out payment3.00%3.00%
Net sales minimum limit for royal payment $ 300,000,000
Payment to be made upon attainment of milestones $ 53,800,000 SFr 50,000,000
River Vision [Member] | FDA Approval [Member]
Loss Contingencies [Line Items]
Net sales100,000,000
Upfront cash payments100,000,000
River Vision [Member] | TEPEZZA [Member]
Loss Contingencies [Line Items]
Payment to be made upon attainment of milestones67,000,000
RAVICTI, BUPHENYL, PROCYSBI, PENNSAID 2%, DUEXIS, RAYOS, QUINSAIR and UPLIZNA [Member]
Loss Contingencies [Line Items]
Purchase and other commitments outstanding purchase orders21,000,000
Teprotumumab [Member] | River Vision [Member] | Net Sales Thresholds [Member]
Loss Contingencies [Line Items]
Net sales225,000,000 $ 225,000,000
AGC Biologics A/S [Member] | TEPEZZA [Member]
Loss Contingencies [Line Items]
Minimum binding purchase commitment $ 89,500,000 € 76.3
Currency exchange rate | $ / €1.1732 1.1732
Catalent [Member] | TEPEZZA Drug Product [Member]
Loss Contingencies [Line Items]
Minimum binding purchase commitment $ 6,400,000
Bio-Technology General (Israel) Ltd [Member] | KRYSTEXXA Developed Technology [Member]
Loss Contingencies [Line Items]
Minimum binding purchase commitment $ 33,000,000
Supply agreement expiry dateDec. 31,
2030
Dec. 31,
2030
Dec. 31,
2030
Term of agreement automatically renewal period3 years3 years3 years
Written notice period for termination of agreement3 years3 years3 years
Expected early termination period of agreement due to uncertain eventJan. 1,
2024
Jan. 1,
2024
Jan. 1,
2024
Purchase commitment outstanding purchase orders $ 1,800,000
Bio-Technology General (Israel) Ltd [Member] | KRYSTEXXA Developed Technology [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Purchase obligation percentage80.00%80.00%80.00%
Boehringer Ingelheim [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Milestone incurred $ 2,000,000
Boehringer Ingelheim [Member] | ACTIMMUNE [Member]
Loss Contingencies [Line Items]
Minimum binding purchase commitment $ 15,000,000
Currency exchange rate | $ / €1.1732 1.1732
S R One And Lundbeckfond [Member] | River Vision [Member]
Loss Contingencies [Line Items]
Percentage of net sales in earn-out payment3.00%3.00%3.00%
Net sales minimum limit for royal payment $ 300,000,000
Percentage of right to receive payments35.66%
Percentage of remaining net obligations payments70.25%
Roche [Member]
Loss Contingencies [Line Items]
Currency exchange rate | $ / SFr1.0382 1.0382 1.0382
Net sales $ 109,200,000 SFr 103,000,000
Milestone incurred $ 5,200,000 SFr 5,000,000 $ 5,200,000 SFr 5,000,000
Roche [Member] | TEPEZZA [Member]
Loss Contingencies [Line Items]
Currency exchange rate | $ / SFr1.1228 1.1228 1.0598 1.0598
Milestone incurred $ 56,100,000 SFr 50,000,000
Roche [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Percentage of net sales in earn-out payment9.00%9.00%
Roche [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Percentage of net sales in earn-out payment12.00%12.00%
Lundquist Institute [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Percentage of net sales in earn-out payment1.00%1.00%1.00%
MedImmune [Member]
Loss Contingencies [Line Items]
Net sales $ 15,000,000
Upfront cash payment $ 45,000,000
TEPEZZA And KRYSTEXXA [Member]
Loss Contingencies [Line Items]
Advertising commitments $ 32,100,000

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Remaining Aggregate Potential Milestone Payments Payable Based on Achievement of Net Sales Thresholds (Detail) - River Vision [Member] - USD ($)Mar. 31, 2021Mar. 31, 2020
Loss Contingencies [Line Items]
Milestone Payment $ 325,000,000 $ 325,000,000
Net Sales Thresholds [Member] | Teprotumumab [Member]
Loss Contingencies [Line Items]
Milestone Payment225,000,000 $ 225,000,000
TEPEZZA Worldwide Net Sales Threshold >$250 million [Member] | Net Sales Thresholds [Member] | Teprotumumab [Member]
Loss Contingencies [Line Items]
Milestone Payment50,000,000
TEPEZZA Worldwide Net Sales Threshold >$375 million [Member] | Net Sales Thresholds [Member] | Teprotumumab [Member]
Loss Contingencies [Line Items]
Milestone Payment75,000,000
TEPEZZA Worldwide Net Sales Threshold >$500million [Member] | Net Sales Thresholds [Member] | Teprotumumab [Member]
Loss Contingencies [Line Items]
Milestone Payment $ 100,000,000

Share-Based and Long-Term Inc_3

Share-Based and Long-Term Incentive Plans - Additional Information (Detail) - USD ($) $ / shares in Units, $ in MillionsMar. 15, 2021Feb. 17, 2021Mar. 31, 2021Mar. 31, 2020Dec. 31, 2020Jan. 05, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options contractual term10 years
Aggregate common stock options exercisable7,785,386 7,129,615
Purchase of ordinary shares were outstanding based on merger agreement[1]1,318,053
Tax benefit (detriment) recognized from stock-based compensation expense $ 53.7 $ 14.1
Pre-tax unrecognized compensation expense for all unvested share-based awards $ 341.5
Cash Incentive Program [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period36 months
Bonus payable under cash bonus program $ 14.1
Cash bonus award maximum target level150.00%
Expense related to cash bonus program $ 0
Performance Stock Unit Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding PSU award vesting amount range150.00%
Performance Stock Unit Awards [Member] | TEPEZZA [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
PSUs outstanding68,459
Performance Stock Unit Awards [Member] | Relative TSR PSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding PSU award vesting amount range50.00%30.00%
Vesting period3 years3 years
Performance Stock Unit Awards [Member] | Tech Ops PSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding PSU award vesting amount range25.00%70.00%
Performance Stock Unit Awards [Member] | R&D PSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding PSU award vesting amount range25.00%
Minimum [Member] | Performance Stock Unit Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding PSU award vesting amount range0.00%
Maximum [Member] | Performance Stock Unit Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding PSU award vesting amount range200.00%
Viela [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate common stock options exercisable2,180,159
Purchase of ordinary shares were outstanding based on merger agreement1,318,053
Viela [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Conversion Rate $ 0.60
Viela [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Conversion Rate $ 1
2020 EIP [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase to number of ordinary shares authorized7,000,000
Common stock shares authorized8,759,022
Common stock shares available for grant8,759,022
2014 ESPP and 2020 ESPP [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares authorized2,994,723
Common stock shares reserved for future issuance2,994,723
2014 Non-Employee Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares authorized574,193
Common stock shares available for grant574,193
2018 EIP [Member] | Viela [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares authorized2,359,550
Common stock shares available for grant2,359,550
[1]On March 15, 2021, the Company completed its acquisition of Viela. Under the terms of the merger agreement for Viela, all outstanding Viela stock options assumed by the Company with vesting dates after June 1, 2021, were converted into stock options to purchase the Company’s ordinary shares. As of March 15, 2021, options previously exercisable for an aggregate of 2,180,159 shares of Viela’s common stock that were converted at a rate of 0.60 to 1 based on the merger agreement, into options to purchase 1,318,053 of the Company’s ordinary shares, were outstanding.

Share-Based and Long-Term Inc_4

Share-Based and Long-Term Incentive Plans - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands3 Months Ended12 Months Ended
Mar. 31, 2021Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options, Outstanding Beginning Balance7,129,615
Assumed in acquisition[1]1,318,053
Options, Exercised(661,780)
Options, Forfeited(268)
Options, Expired(234)
Options, Outstanding Ending Balance7,785,386 7,129,615
Options, Exercisable as of March 31, 20216,771,755
Weighted Average Exercise Price, Outstanding Beginning Balance $ 21.24
Assumed in acquisition[1]41.23
Weighted Average Exercise Price, Exercised30.06
Weighted Average Exercise Price, Forfeited17.19
Weighted Average Exercise Price, Expired17.32
Weighted Average Exercise Price, Outstanding Ending Balance23.88 $ 21.24
Weighted Average Exercise Price, Exercisable as of March 31, 2021 $ 21.40
Weighted Average Contractual Term Remaining (in years)4 years 9 months 25 days4 years 7 months 6 days
Weighted Average Contractual Term Remaining (in years) Exercisable as of March 31,20214 years 3 months 10 days
Aggregate Intrinsic Value $ 530,665 $ 370,073
Aggregate Intrinsic Value, Exercisable as of March 31, 2021 $ 478,349
[1]On March 15, 2021, the Company completed its acquisition of Viela. Under the terms of the merger agreement for Viela, all outstanding Viela stock options assumed by the Company with vesting dates after June 1, 2021, were converted into stock options to purchase the Company’s ordinary shares. As of March 15, 2021, options previously exercisable for an aggregate of 2,180,159 shares of Viela’s common stock that were converted at a rate of 0.60 to 1 based on the merger agreement, into options to purchase 1,318,053 of the Company’s ordinary shares, were outstanding.

Share-Based and Long-Term Inc_5

Share-Based and Long-Term Incentive Plans - Summary of Restricted Stock Unit Activity (Detail) - Restricted Stock Units [Member]3 Months Ended
Mar. 31, 2021$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Units, Outstanding Beginning Balance | shares5,909,120
Number of Units, Granted | shares1,851,309
Number of Units, Vested | shares(2,350,056)
Number of Units, Forfeited | shares(95,177)
Number of Units, Outstanding Ending Balance | shares5,315,196
Weighted Average Grant-Date Fair Value Per Unit, Outstanding Beginning Balance | $ / shares $ 27.87
Weighted Average Grant-Date Fair Value Per Unit, Granted | $ / shares73.82
Weighted Average Grant-Date Fair Value Per Unit, Vested | $ / shares23.19
Weighted Average Grant-Date Fair Value Per Unit, Forfeited | $ / shares56.21
Weighted Average Grant-Date Fair Value Per Unit, Outstanding Ending Balance | $ / shares $ 45.44

Share-Based and Long-Term Inc_6

Share-Based and Long-Term Incentive Plans - Summary of Performance Stock Unit Awards Activity (Detail) - Performance Stock Unit Awards [Member]3 Months Ended
Mar. 31, 2021$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Units, Outstanding Beginning Balance | shares2,610,924
Number of Units, Granted | shares450,577
Number of Units, Forfeited | shares(24,450)
Number of Units, Vested | shares(2,021,657)
Number of Units, Performance Based Adjustments | shares512,819 [1]
Number of Units, Outstanding Ending Balance | shares1,528,213
Weighted Average Grant-Date Fair Value Per Unit, Granted $ 93.73
Weighted Average Grant-Date Fair Value Per Unit, Forfeited93.73
Weighted Average Grant-Date Fair Value Per Unit, Vested21.21
Weighted Average Grant-Date Fair Value Per Unit, Performance Based Adjustments $ 25.42 [1]
Average Illiquidity discount, Granted8.64%
Average Illiquidity discount, Forfeited9.21%
Average Illiquidity discount, Vested2.66%
Average Illiquidity discount, Performance Based Adjustments7.27%[1]
Recorded Weighted Average Fair Value Per Unit, Granted $ 85.64
Recorded Weighted Average Fair Value Per Unit, Forfeited85.10
Recorded Weighted Average Fair Value Per Unit, Vested20.65
Recorded Weighted Average Fair Value Per Unit, Performance Based Adjustments $ 23.57 [1]
[1]Represents adjustment based on the net sales performance criteria meeting 162.5% of target as of December 31, 2020 for the 2020 PSUs (as defined below), the net sales performance criteria meeting 200.0% of target as of December 31, 2020 for the TEPEZZA PSUs (as defined below) and meeting total shareholder return (“TSR”) performance at 200.0% for the PSUs that were awarded to key executive participants on January 5, 2018.

Share-Based and Long-Term Inc_7

Share-Based and Long-Term Incentive Plans - Summary of Performance Stock Unit Awards Activity - (Parenthetical) (Detail) - Performance Stock Unit Awards [Member]Jan. 05, 2018Dec. 31, 2020
Tech Ops PSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of net sales performance criteria met162.50%
TEPEZZA [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of net sales performance criteria met200.00%
Key Executive PSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of net sales performance criteria met200.00%

Share-Based and Long-Term Inc_8

Share-Based and Long-Term Incentive Plans - Summary of Significant Valuation Assumptions Related to 2020 PSUs (Detail) - Performance Stock Unit Awards [Member]3 Months Ended
Mar. 31, 2021$ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Valuation date stock price $ 72.54
Expected volatility45.80%
Risk free rate0.20%

Share-Based and Long-Term Inc_9

Share-Based and Long-Term Incentive Plans - Summary of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense $ 61,166 $ 56,421
Cost of Goods Sold [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense1,936 2,689
Research and Development [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense5,616 6,376
Selling, General and Administrative Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense $ 53,614 $ 47,356

Income Taxes - Benefit for Inco

Income Taxes - Benefit for Income Taxes (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Income Tax Disclosure [Abstract]
Loss before benefit for income taxes $ (171,102) $ (32,617)
Benefit for income taxes(47,751)(19,026)
Net loss $ (123,351) $ (13,591)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands3 Months Ended
Mar. 31, 2021Mar. 31, 2020
Income Tax Disclosure [Abstract]
Benefit for income taxes $ 47,751 $ 19,026