Mallinckrodt Rheumatoid Arthritis Phase 4 Clinical Study for H.P. Acthar® Gel (Repository Corticotropin Injection) Achieves its Enrollment Target

STAINES-UPON-THAMES, United Kingdom /PRNewswire/ -- Mallinckrodt plc (NYSE: MNK), a leading global specialty pharmaceutical company, today announced it has completed enrollment of the company's ongoing Phase 4 clinical trial of H.P. Acthar^® Gel for Rheumatoid Arthritis (RA) patients. The study is assessing the efficacy and safety of H.P. Acthar Gel in RA patients with persistently active disease. Target enrollment was 230 patients, and that goal has been exceeded.

"This is an exciting milestone achievement in this important clinical trial," said Steven Romano, MD, Executive Vice President and Chief Scientific Officer at Mallinckrodt. "As prescribers consider the potential benefit H.P. Acthar Gel may provide for appropriate RA patients with persistent disease activity, we are hopeful the findings from this study will help guide those decisions."

H.P. Acthar Gel is U.S. Food and Drug Administration (FDA)-approved as adjunctive therapy for short-term administration (to tide the patient over an acute episode or exacerbation) in rheumatoid arthritis including juvenile rheumatoid arthritis (selected cases may require low-dose maintenance therapy).

Mallinckrodt recently reported interim findings of the study at the Annual European Congress of Rheumatology (EULAR 2018). Details on that data presentation are available here. As the study continues to progress, the company plans to present additional data at future conferences.

Mark Trudeau, President and Chief Executive Officer at Mallinckrodt, said, "Our clinical programs for H.P.  Acthar Gel are conducted specifically to further establish its clinical utility in tough-to-treat patient populations, including approved, later-line indications outside infantile spasms, where the drug is considered standard of care. It is our intent to use the data from these programs to better inform prescribers, facilitating access for appropriate patients in both commercial plans and government programs."

Study Details
The study is a Phase 4, multicenter, two-part study assessing the efficacy and safety of H.P. Acthar Gel in adult subjects with rheumatoid arthritis with persistently active disease that has completed enrollment. Part 1 is an Open Label Period in which all eligible subjects receive H.P. Acthar Gel for 12 weeks. After 12 weeks of treatment with H.P. Acthar Gel, subjects will be evaluated for treatment response using the Disease Activity Score 28-joint count Erythrocyte Sedimentation Rate (DAS28-ESR). Subjects who have achieved low disease activity will enter a double-blind randomized maintenance period (Part 2) and be randomized in a 1:1 ratio to receive either H.P. Acthar Gel or matching placebo for an additional 12 weeks.

The trial is fully enrolled, and all subjects are patients with persistently active RA despite treatment with corticosteroids and conventional synthetic and/or biologic disease-modifying anti-rheumatic drugs (DMARDs) for the primary outcome. The primary endpoint in this study is the proportion of subjects with DAS28-ESR <3.2 at Week 12. The Secondary Outcome Measures include the proportion of subjects who maintained DAS28-ESR <3.2 from Week 12 through Week 24.

Find more information about the study here on the ClinicalTrials.gov website.

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ABOUT RHEUMATOID ARTHRITIS
RA is an autoimmune disease. It is a chronic condition that causes pain, stiffness, and swelling of the joints—all symptoms caused by inflammation. An estimated 1.5 million U.S. adults are living with RA.¹ Treatment is aimed at stopping inflammation to put the disease in remission and relieve symptoms.² Nonsteroidal anti-inflammatory drugs are used to ease symptoms whereas corticosteroids, disease-modifying anti-rheumatic drugs and biologics are used to slow down the disease activity.

About H.P. Acthar Gel (repository corticotropin injection) Indications 
H.P. Acthar Gel is an injectable drug approved by the FDA for the treatment of 19 indications. Of these, today the majority of Acthar use is in these indications:

• Adjunctive therapy for short-term administration (to tide the patient over an acute episode or exacerbation) in rheumatoid arthritis, including juvenile rheumatoid arthritis (selected cases may require low-dose maintenance therapy)
• Monotherapy for the treatment of infantile spasms in infants and children under 2 years of age
• Treatment during an exacerbation or as maintenance therapy in selected cases of systemic lupus erythematosus
• The treatment of acute exacerbations of multiple sclerosis in adults. Controlled clinical trials have shown H.P. Acthar Gel to be effective in speeding the resolution of acute exacerbations of multiple sclerosis. However, there is no evidence that it affects the ultimate outcome or natural history of the disease
• Inducing a diuresis or a remission of proteinuria in nephrotic syndrome without uremia of the idiopathic type or that due to lupus erythematosus
• Treatment during an exacerbation or as maintenance therapy in selected cases of systemic dermatomyositis (polymyositis)
• The treatment of symptomatic sarcoidosis
• Treatment of severe acute and chronic allergic and inflammatory processes involving the eye and its adnexa such as: keratitis, iritis, iridocyclitis, diffuse posterior uveitis and choroiditis, optic neuritis, chorioretinitis, anterior segment inflammation

IMPORTANT SAFETY INFORMATION
Contraindications

• Acthar should never be administered intravenously
• Administration of live or live attenuated vaccines is contraindicated in patients receiving immunosuppressive doses of Acthar
• Acthar is contraindicated where congenital infections are suspected in infants
• Acthar is contraindicated in patients with scleroderma, osteoporosis, systemic fungal infections, ocular herpes simplex, recent surgery, history of or the presence of a peptic ulcer, congestive heart failure, uncontrolled hypertension, primary adrenocortical insufficiency, adrenocortical hyperfunction or sensitivity to proteins of porcine origins

Warnings and Precautions

• The adverse effects of Acthar are related primarily to its steroidogenic effects
• Acthar may increase susceptibility to new infection or reactivation of latent infections
• Suppression of the hypothalamic-pituitary-axis (HPA) may occur following prolonged therapy with the potential for adrenal insufficiency after withdrawal of the medication. Adrenal insufficiency may be minimized by tapering of the dose when discontinuing treatment. During recovery of the adrenal gland patients should be protected from the stress (e.g. trauma or surgery) by the use of corticosteroids. Monitor patients for effects of HPA suppression after stopping treatment
• Cushing's syndrome may occur during therapy but generally resolves after therapy is stopped. Monitor patients for signs and symptoms
• Acthar can cause elevation of blood pressure, salt and water retention, and hypokalemia. Blood pressure, sodium and potassium levels may need to be monitored
• Acthar often acts by masking symptoms of other diseases/disorders. Monitor patients carefully during and for a period following discontinuation of therapy
• Acthar can cause GI bleeding and gastric ulcer. There is also an increased risk for perforation in patients with certain gastrointestinal disorders. Monitor for signs of bleeding
• Acthar may be associated with central nervous system effects ranging from euphoria, insomnia, irritability, mood swings, personality changes, and severe depression, and psychosis. Existing conditions may be aggravated
• Patients with comorbid disease may have that disease worsened. Caution should be used when prescribing Acthar in patients with diabetes and myasthenia gravis
• Prolonged use of Acthar may produce cataracts, glaucoma and secondary ocular infections. Monitor for signs and symptoms
• Acthar is immunogenic and prolonged administration of Acthar may increase the risk of hypersensitivity reactions. Neutralizing antibodies with chronic administration may lead to loss of endogenous ACTH activity
• There is an enhanced effect in patients with hypothyroidism and in those with cirrhosis of the liver
• Long-term use may have negative effects on growth and physical development in children. Monitor pediatric patients
• Decrease in bone density may occur. Bone density should be monitored for patients on long-term therapy
• Pregnancy Class C: Acthar has been shown to have an embryocidal effect and should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus

Adverse Reactions

• Common adverse reactions for Acthar are similar to those of corticosteroids and include fluid retention, alteration in glucose tolerance, elevation in blood pressure, behavioral and mood changes, increased appetite and weight gain
• Specific adverse reactions reported in IS clinical trials in infants and children under 2 years of age included: infection, hypertension, irritability, Cushingoid symptoms, constipation, diarrhea, vomiting, pyrexia, weight gain, increased appetite, decreased appetite, nasal congestion, acne, rash, and cardiac hypertrophy. Convulsions were also reported, but these may actually be occurring because some IS patients progress to other forms of seizures and IS sometimes mask other seizures, which become visible once the clinical spasms from IS resolve

Other adverse events reported are included in the full Prescribing Information.
Please see full Prescribing Information.

CAUTIONARY STATEMENTS RELATED TO FORWARD-LOOKING STATEMENTS

This release includes forward-looking statements concerning H.P. Acthar Gel including expectations with regard to the study described in this release, as well as future research plans and potential impact on patients. The statements are based on assumptions about many important factors, including the following, which could cause actual results to differ materially from those in the forward-looking statements: satisfaction of regulatory and other requirements; actions of regulatory bodies and other governmental authorities; changes in laws and regulations; issues with product quality, manufacturing or supply, or patient safety issues; and other risks identified and described in more detail in the "Risk Factors" section of Mallinckrodt's most recent Annual Report on Form 10-K and other filings with the SEC, all of which are available on its website. The forward-looking statements made herein speak only as of the date hereof and Mallinckrodt does not assume any obligation to update or revise any forward-looking statement, whether as a result of new information, future events and developments or otherwise, except as required by law.

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CONTACTS

Investor Relations
Daniel J. Speciale, CPA
Investor Relations and Strategy Officer
314-654-3638
daniel.speciale@mnk.com

Media
Rhonda Sciarra
Senior Communications Manager
908-238-6765
rhonda.sciarra@mnk.com

Meredith Fischer
Chief Public Affairs Officer
314-654-3318
meredith.fischer@mnk.com

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