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, 2022 are not necessarily indicative of the results that may be expected for the year ending December 31, 2022. The December 31, 2021 condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP.

Horizon is focused on the discovery, development and commercialization of medicines that address critical needs for people impacted by rare, autoimmune and severe 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 commercial portfolio is currently composed of 12 medicines in the areas of rare diseases, gout, ophthalmology and inflammation.

As of March 31, 2022, the Company’s commercial portfolio consisted of the following medicines:

Orphan

TEPEZZA^® (teprotumumab-trbw), for intravenous infusion

KRYSTEXXA^® (pegloticase injection), for intravenous infusion

RAVICTI^® (glycerol phenylbutyrate) oral liquid

PROCYSBI^® (cysteamine bitartrate) delayed-release capsules and granules, for oral use

ACTIMMUNE^® (interferon gamma-1b) injection, for subcutaneous use

UPLIZNA^® (inebilizumab-cdon) injection, for intravenous use

BUPHENYL^® (sodium phenylbutyrate) tablets and powder, for oral use

QUINSAIR^™ (levofloxacin) solution for inhalation

Inflammation

PENNSAID^® (diclofenac sodium topical solution) 2% w/w (“PENNSAID 2%”), for topical use

RAYOS^® (prednisone) delayed-release tablets, for oral use

DUEXIS^® (ibuprofen/famotidine) tablets, for oral use

VIMOVO^® (naproxen/esomeprazole magnesium) delayed-release tablets, for oral use