DUBLIN, IRELAND–(Marketwired – May 11, 2016) – Horizon Pharma plc (NASDAQ: HZNP), a biopharmaceutical company focused on improving patients’ lives by identifying, developing, acquiring and commercializing differentiated and accessible medicines that address unmet medical needs, today announced it received a Notice of Allowance from the United States Patent and Trademark Office (USPTO) for U.S. patent application number 13/379,704 (U.S. publication number 2012-0301454), entitled “Methods and Kits for Predicting Infusion Reaction Risk and Antibody-Mediated Loss of Response by Monitoring Serum Uric Acid During Pegylated Uricase Therapy” that covers Horizon’s U.S. approved medicine KRYSTEXXA® (pegloticase).

The Notice of Allowance concludes the substantive examination of the patent application and will result in the issuance of a U.S. patent after administrative processes are completed. The U.S. patent scheduled to issue from this application will expire June 25, 2030.

About KRYSTEXXA
KRYSTEXXA (pegloticase) is a PEGylated uric acid specific enzyme and the first and only FDA-approved medicine indicated for the treatment of chronic gout in adult patients refractory to conventional therapy, which occurs when uric acid build up in the blood remains high and inflammation persists even after treatment with conventional therapies. According to estimates, chronic refractory gout impacts approximately 50,000 people in the United States. For more information, please see www.KRYSTEXXA.com.

IMPORTANT SAFETY INFORMATION

Important Limitations of Use:
KRYSTEXXA is not recommended for the treatment of asymptomatic hyperuricemia.

WARNING: ANAPHYLAXIS AND INFUSION REACTIONS

• Anaphylaxis and infusion reactions have been reported to occur during and after administration of KRYSTEXXA.
• Anaphylaxis may occur with any infusion, including a first infusion, and generally manifests within 2 hours of the infusion.
• However, delayed-type hypersensitivity reactions have also been reported.
• KRYSTEXXA should be administered in healthcare settings and by healthcare providers prepared to manage anaphylaxis and infusion reactions.
• Patients should be premedicated with antihistamines and corticosteroids.
• Patients should be closely monitored for an appropriate period of time for anaphylaxis after administration of KRYSTEXXA.
• Monitor serum uric acid levels prior to infusions and consider discontinuing treatment if levels increase to above 6 mg/dL, particularly when 2 consecutive levels above 6 mg/dL are observed.

CONTRAINDICATIONS

• Glucose-6-phosphate dehydrogenase (G6PD) Deficiency: Before starting KRYSTEXXA, confirm patients are not G6PD deficient. Patients at higher risk for G6PD deficiency (e.g., those of African and Mediterranean ancestry) should be screened because of the risk of hemolysis and methemoglobinemia, however any patient could be affected.

WARNINGS AND PRECAUTIONS

• Anaphylaxis: Anaphylaxis occurred in patients treated with KRYSTEXXA. Anaphylaxis may occur with any infusion, including a first infusion, and generally manifests within 2 hours of the infusion. However, delayed-type hypersensitivity reactions have also been reported. KRYSTEXXA should be administered in healthcare settings and by healthcare providers prepared to manage anaphylaxis. Patients should be premedicated with antihistamines and corticosteroids. Patients should be closely monitored for an appropriate period of time for anaphylaxis after administration of KRYSTEXXA.
• Infusion Reactions: Infusion reactions occurred in patients treated with KRYSTEXXA. KRYSTEXXA should be administered in a healthcare setting and by healthcare providers prepared to manage infusion reactions. Patients should be premedicated with antihistamines and corticosteroids. Monitor patients closely for signs and symptoms of infusion reactions. In the event of an infusion reaction, the infusion should be slowed, or stopped and restarted at a slower rate. If a severe infusion reaction occurs, discontinue infusion and institute treatment as needed. The risk of an infusion reaction is higher in patients who have lost therapeutic response.
  • Monitor serum uric acid levels prior to infusions and consider discontinuing treatment if levels increase to above 6 mg/dL, particularly when 2 consecutive levels above 6 mg/dL are observed.
  • Concomitant use of KRYSTEXXA and oral urate-lowering agents may blunt the rise of serum uric acid levels. It is recommended that patients discontinue oral urate-lowering agents and not institute therapy with oral urate-lowering agents while taking KRYSTEXXA.
• Gout Flares: An increase in gout flares is frequently observed upon initiation of antihyperuricemic therapy, including treatment with KRYSTEXXA. If a gout flare occurs during treatment, KRYSTEXXA need not be discontinued. Gout flare prophylaxis with a nonsteroidal anti-inflammatory drug (NSAID) or colchicine is recommended starting at least 1 week before initiation of KRYSTEXXA therapy and lasting at least 6 months, unless medically contraindicated or not tolerated.
• Congestive Heart Failure: KRYSTEXXA has not been formally studied in patients with congestive heart failure, but some patients in clinical trials experienced exacerbation. Exercise caution when using KRYSTEXXA in patients who have congestive heart failure, and monitor patients closely following infusion.
• Re-treatment: No controlled clinical data is available on the safety and efficacy of re-treatment with KRYSTEXXA after stopping treatment for longer than 4 weeks. Patients receiving re-treatment may be at increased risk for anaphylaxis and infusion reactions and should be monitored carefully.

ADVERSE REACTIONS
The most commonly reported serious adverse reactions in the pivotal trial with the approved regimen of 8 mg KRYSTEXXA administered every 2 weeks were gout flares, infusion reactions, and anaphylaxis. Most common adverse reactions: gout flares (77%), infusion reactions (26%), nausea (12%), contusion or ecchymosis (11%), nasopharyngitis (7%), constipation (6%), chest pain (6%), anaphylaxis (5%), and vomiting (5%). In addition to events occurring in greater than 5%, exacerbation of pre-existing congestive heart failure occurred in 2%.

Please see the Medication Guide and Prescribing Information, including Boxed Warning, located at www.krystexxa.com for more information.

About Horizon Pharma plc
Horizon Pharma plc is a biopharmaceutical company focused on improving patients’ lives by identifying, developing, acquiring and commercializing differentiated and accessible medicines that address unmet medical needs. The Company markets nine medicines through its orphan, rheumatology and primary care business units. Horizon’s global headquarters are in Dublin, Ireland. For more information, please visit www.horizonpharma.com. Follow @HZNPplc on Twitter or view careers on our LinkedIn page.

Forward-Looking Statements
This press release contains forward-looking statements, including statements regarding the potential issuance of a patent based on the Notice of Allowance from the U.S. Patent and Trademark Office, the expected terms of the patent, if issued, and potential patent protection for KRYSTEXXA. These forward-looking statements are based on management expectations and assumptions as of the date of this press release, and actual results may differ materially from those in these forward-looking statements as a result of various factors. These factors include risks regarding whether the administrative processes required for the issuance of the patent as indicated in the Notice of Allowance will be completed in a timely matter or at all, whether the patent, if issued as indicated in the Notice of Allowance, will provide sufficient protection and market exclusivity for KRYSTEXXA, whether any patent covering KRYSTEXXA may be challenged, invalidated, infringed or circumvented by third parties and other factors described in Horizon’s filings with the United States Securities and Exchange Commission, including those factors discussed under the caption “Risk Factors” in those filings. Forward-looking statements speak only as of the date of this press release and Horizon does not undertake any obligation to update or revise these statements, except as may be required by law.