Statement on Short-Term TEPEZZA® (teprotumumab-trbw) Supply Disruption

Updated February 1, 2021

Horizon announced that it has submitted a prior approval supplement to the U.S. Food and Drug Administration (FDA) to support increased scale production of TEPEZZA® (teprotumumab-trbw) drug product for the treatment of Thyroid Eye Disease (TED).  The submission includes data to support more product output with each manufacturing slot than is currently approved by the FDA.  The Company will continue to discuss potential additional data requirements and approval timeline with the FDA.

As previously announced on Dec. 17, 2020, this increased production capacity is necessary due to government-mandated COVID-19 vaccine production orders pursuant to the Defense Production Act of 1950 (DPA) related to manufacturing that dramatically reduced the number of drug product production slots available to Horizon at Catalent Biologic, the contract manufacturer that completes the final step in the production of TEPEZZA.  Horizon is working closely with the FDA to expedite the review of the supplement, which is an important step towards resolving the shortage.

“We commend efforts to accelerate COVID-19 vaccine production, and our number one priority at this time is to end the short-term TEPEZZA supply disruption as quickly as we can in order to get patients back on therapy,” said Tim Walbert, chairman, president and chief executive officer, Horizon.  “We continue to anticipate the disruption could last through the first quarter of 2021; however, we have worked swiftly to compile and submit data from the increased scale production and appreciate that the FDA is willing to partner with us and expedite its review.”

Information for Patients
Horizon’s priority is to resume therapy for patients as quickly as possible.  Additional information about the short-term disruption in supply is available in our FAQ here.  Patients can also contact Horizon Patient Services at 1-833-469-8331.

Information for Health Care Professionals
Physicians with questions should call 1-866-479-6742 or email medicalinformation@horizontherapeutics.com.

About TEPEZZA

INDICATION

TEPEZZA is indicated for the treatment of Thyroid Eye Disease.

IMPORTANT SAFETY INFORMATION
Warnings and Precautions

Infusion Reactions:  TEPEZZA may cause infusion reactions.  Infusion reactions have been reported in approximately 4% of patients treated with TEPEZZA.  Reported infusion reactions have usually been mild or moderate in severity.  Signs and symptoms may include transient increases in blood pressure, feeling hot, tachycardia, dyspnea, headache and muscular pain.  Infusion reactions may occur during an infusion or within 1.5 hours after an infusion.  In patients who experience an infusion reaction, consideration should be given to premedicating with an antihistamine, antipyretic or corticosteroid and/or administering all subsequent infusions at a slower infusion rate.

Preexisting Inflammatory Bowel Disease:  TEPEZZA may cause an exacerbation of preexisting inflammatory bowel disease (IBD).  Monitor patients with IBD for flare of disease.  If IBD exacerbation is suspected, consider discontinuation of TEPEZZA.

Hyperglycemia:  Increased blood glucose or hyperglycemia may occur in patients treated with TEPEZZA.  In clinical trials, 10% of patients (two-thirds of whom had preexisting diabetes or impaired glucose tolerance) experienced hyperglycemia.  Hyperglycemic events should be managed with medications for glycemic control, if necessary.  Monitor patients for elevated blood glucose and symptoms of hyperglycemia while on treatment with TEPEZZA.  Patients with preexisting diabetes should be under appropriate glycemic control before receiving TEPEZZA.

Adverse Reactions

The most common adverse reactions (incidence ≥5% and greater than placebo) are muscle spasm, nausea, alopecia, diarrhea, fatigue, hyperglycemia, hearing impairment, dysgeusia, headache and dry skin.

For additional information on TEPEZZA, please see Full Prescribing Information at TEPEZZAhcp.com.

About Horizon
Horizon is focused on researching, developing and commercializing medicines that address critical needs for people impacted by rare and rheumatic diseases.  Our pipeline is purposeful:  we apply scientific expertise and courage to bring clinically meaningful therapies to patients.  We believe science and compassion must work together to transform lives.  For more information on how we go to incredible lengths to impact lives, please visit www.horizontherapeutics.com and follow us on Twitter, LinkedIn, Instagram and Facebook.

Forward-Looking Statements
This press release contains forward-looking statements, including, but not limited to, statements related to the anticipated impact of recent government orders on TEPEZZA supply, the potential approval of Horizon’s prior approval supplement to support increased scale production of TEPEZZA, the potential impact of an approval of the supplement on TEPEZZA supply, expectations regarding the length of TEPEZZA supply disruptions; and business and other statements that are not historical facts.  These forward-looking statements are based on Horizon’s current expectations and inherently involve significant risks and uncertainties.  Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties, which include, without limitation, the risk that further TEPEZZA manufacturing run cancellations, whether as a result of additional government orders or other issues at Horizon’s third party manufacturers or failed manufacturing runs could exacerbate and prolong TEPEZZA supply disruptions; uncertainty with respect to timing of the FDA’s review of Horizon’s prior approval supplement; whether the supplement is approved; uncertainty regarding the impact of the TEPEZZA supply disruption on TEPEZZA’s long-term commercial potential; impacts of the COVID-19 pandemic and actions taken to slow its spread; risks relating to Horizon’s ability to successfully implement its business strategies; risks associated with regulatory approvals; regulatory obligations and oversight, including any changes in the legal and regulatory environment in which Horizon operates and those risks detailed from time-to-time under the caption “Risk Factors” and elsewhere in Horizon’s filings and reports with the SEC.  Horizon undertakes no duty or obligation to update any forward-looking statements contained in this press release as a result of new information.

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