Mallinckrodt Halts Phase 2B Trial Investigating the Use of Acthar® Gel (Repository Corticotropin Injection) in Amyotrophic Lateral Sclerosis (ALS)

STAINES-UPON-THAMES, United Kingdom, July 16, 2019 /PRNewswire/ -- Mallinckrodt plc (NYSE: MNK), a leading global specialty biopharmaceutical company, today announced that it is permanently discontinuing its Phase 2B study designed to assess the efficacy and safety of Acthar^® Gel (repository corticotropin injection) as an investigational treatment for amyotrophic lateral sclerosis (ALS). The drug is not U.S. Food and Drug Administration (FDA)-approved for the ALS indication. Please see Important Safety Information for Acthar Gel below.

Mallinckrodt made the decision to halt the trial after careful consideration of a recent recommendation by the study's independent Data and Safety Monitoring Board (DSMB). The DSMB was created by the company following industry best practice to ensure the safety of patients participating in a clinical study. This oversight is accomplished through ongoing review of semi-blinded information as the study is being conducted, and is typically done when there is limited information available in the patient population being studied.

The recommendation was based on the specific concern for pneumonia, which occurred at a higher rate in the ALS patients receiving Acthar Gel compared to those on placebo; the board also mentioned other adverse events specific to this patient population. The DSMB noted the proportion of patients who have completed Week 36 – the primary endpoint target – precludes a definitive determination of a treatment effect. The lack of a clear efficacy signal for this ALS patient population combined with the potential risk of pneumonia led to the board's recommendation.

After careful analysis, Mallinckrodt agreed that the study should be permanently halted in the interest of patient safety for this fragile population, one for which pneumonia is a particularly serious condition. Enrollment in the study will cease immediately, and those patients already enrolled will be tapered off the drug before discontinuing use.

"Mallinckrodt's primary focus is on the safety of patients and, while ALS patients are among those most in need of new therapies and treatment options, we believe this is the right decision. It is critical to stress, however, that these findings do not impact the current positive benefit/risk profile of Acthar for use in current on-label indications," said Steven Romano, M.D., Executive Vice President and Chief Scientific Officer at Mallinckrodt. "Though the probability of success for the ALS population was acknowledged as being low, this study was initiated based on compelling analyses carried out following the completion of a small pilot study and we were hopeful it would have translated into a benefit for this group of patients in great need of effective therapies. We thank the DSMB, the investigators and the patients who participated in the study."

This action does not affect any other ongoing clinical studies for Acthar Gel. Mallinckrodt is committed to responsible and ethical scientific exploration that adds to the body of clinical and economic data for critical illnesses. Mallinckrodt has invested more than $500 million into Acthar Gel's modernization, specifically initiating company-sponsored clinical studies building on substantial clinical experience as well as previously completed and largely independent clinical case series and smaller trials; modernizing manufacturing; and expanding medical affairs and research activities. The company's investment into Acthar Gel and these activities remains an important focus.

About the PENNANT Trial
The Phase 2B clinical study is titled "A Multicenter, Double Blind, Placebo-Controlled Study to Assess the Efficacy and Safety of Acthar Gel in the Treatment of Subjects with Amyotrophic Lateral Sclerosis." The study targeted enrollment of patients ages 18 to 75 with ALS and symptom onset (defined as first muscle weakness or dysarthria) ≤ two years prior to the screening visit. Subjects were randomized on a 2:1 basis to receive subcutaneous (SC) Acthar Gel 0.2 mL (16 units) daily or SC matching placebo 0.2 mL daily for 36 weeks.

The efficacy of Acthar Gel was assessed using standard measures of functional decline, including change from baseline in the ALS Functional Rating Scale-Revised, assessed after 36 weeks of therapy.

About ALS
ALS is a progressive neurodegenerative disease that affects motor neuron cells in the brain and the spinal cord. Motor neurons reach from the brain and the spinal cord to the muscles throughout the body. The progressive degeneration of the motor neurons in ALS eventually leads to their demise and when the motor neurons die, voluntary and involuntary muscle movement is lost. With the progressive loss of motor neurons, people with ALS may lose the ability to speak, eat, move and breathe.¹ 

Acthar Gel (repository corticotropin injection) Indications
Acthar Gel is an injectable drug approved by the FDA for the treatment of 19 indications. Of these, today the majority of Acthar Gel 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)
• The treatment of symptomatic sarcoidosis
• 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 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)
• 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.

ABOUT MALLINCKRODT
Mallinckrodt is a global business consisting of multiple wholly owned subsidiaries that develop, manufacture, market and distribute specialty pharmaceutical products and therapies. The company's Specialty Brands reportable segment's areas of focus include autoimmune and rare diseases in specialty areas like neurology, rheumatology, nephrology, pulmonology and ophthalmology; immunotherapy and neonatal respiratory critical care therapies; analgesics and gastrointestinal products. Its Specialty Generics reportable segment includes specialty generic drugs and active pharmaceutical ingredients. To learn more about Mallinckrodt, visit www.mallinckrodt.com.

Mallinckrodt uses its website as a channel of distribution of important company information, such as press releases, investor presentations and other financial information. It also uses its website to expedite public access to time-critical information regarding the company in advance of or in lieu of distributing a press release or a filing with the U.S. Securities and Exchange Commission (SEC) disclosing the same information. Therefore, investors should look to the Investor Relations page of the website for important and time-critical information. Visitors to the website can also register to receive automatic e-mail and other notifications alerting them when new information is made available on the Investor Relations page of the website.

CAUTIONARY STATEMENTS RELATED TO FORWARD-LOOKING STATEMENTS
This release includes forward-looking statements with regard to Acthar Gel including expectations specific to this Phase 2B study, as well as its 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: clinical trial results; 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.

CONTACTS

Media
Daniel Yunger
Kekst CNC
212-521-4879
[email protected]

Investor Relations
Daniel J. Speciale, CPA
Vice President, Investor Relations and IRO
314-654-3638
[email protected]

Mallinckrodt, the "M" brand mark and the Mallinckrodt Pharmaceuticals logo are trademarks of a Mallinckrodt company. Other brands are trademarks of a Mallinckrodt company or their respective owners. © 2019 Mallinckrodt. US-1901063 7/19

¹ The ALS Association, Our Research, Focus Areas, Disease Mechanisms. http://www.alsa.org/research/focus-areas/disease-mechanisms/ Accessed June 17, 2019.

SOURCE Mallinckrodt plc