News Release
                    
                Mallinckrodt Pharmaceuticals Reports Human Abuse Liability (HAL) Data for MNK-795, an Extended-Release Oxycodone/Acetaminophen Combination
                
      HAL study compares abuse-related characteristics of MNK-795 with
      Percocet®
    
    LAS VEGAS--(BUSINESS WIRE)--Sep. 4, 2013--
      Mallinckrodt
      (NYSE: MNK) today reported data from a Human Abuse Liability (HAL) study
      comparing certain abuse-related characteristics of MNK-795 with those of
      Percocet (an immediate-release oxycodone/acetaminophen formulation). In
      the HAL study, intact and crushed MNK-795 had statistically
      significant (p <0.001) lower measures of drug liking, drug
      high, and good drug effects than comparable doses of Percocet when
      measured at the peak drug effect (Emax). The data are being
      presented at PAINWeek, a national conference on pain for frontline
      practitioners, taking place in Las Vegas September 4-7, 2013.
    
      MNK-795 is an investigational, extended-release, oral formulation of
      oxycodone and acetaminophen that has been studied for the management of
      moderate to severe acute pain where the use of an opioid analgesic is
      appropriate. In July, the U.S. Food and Drug Administration (FDA)
      accepted for filing the New Drug Application for MNK-795 and granted
      priority review.
    
      The problems of potential misuse and abuse of opioid pain medications
      are a key focus for the FDA with regard to evaluation of new medications
      for potential use in pain management. Included in the FDA’s Guidance
      for Industry: Abuse-Deterrent Opioids – Evaluation and Labeling
      (January 2013), HAL studies are relatively new for investigational pain
      medications. These studies are an important tool for the FDA to assess
      the relative abuse potential of a new drug. For drugs with
      abuse-deterrent properties, a HAL study assesses the impact of the
      potentially abuse-deterrent formulation on measures that predict how
      probable it is that the medication will be attractive to abusers. The
      industry guidance recommends that a Visual Analog Scale (VAS) be used to
      measure drug liking, drug high, good drug effects, and other qualities,
      as it appears to correlate most directly with potential for abuse.
    
      “These results are significant in the field of acute pain management, as
      MNK-795 is the first oxycodone/acetaminophen combination reported to
      meet all three of these endpoints (drug liking, drug high, and good drug
      effects) in a human abuse liability or HAL study,” said Lynn Webster,
      M.D., co-founder and chief medical director of Lifetree Clinical Research®,
      who led the study. “Oxycodone and acetaminophen combinations are widely
      used for managing acute pain, but are commonly abused. There is a real
      need for improved formulations that address patient and physician
      concerns about these kinds of medications.”
    
      HAL Study Details
    
      The HAL study was a single-center, randomized, double-blind,
      double-dummy, active- and placebo-controlled, 7-way crossover study
      assessing the abuse potential of MNK-795 in 55 healthy male and female
      non-dependent recreational opioid users. During the seven treatment
      periods, subjects received a single treatment with one of the seven
      study drugs:
    
      - 
        Placebo
      
 
      - 
        15 mg/650 mg MNK-795 (low dose, intact)
      
 
      - 
        15 mg/650 mg Percocet (low dose, intact)
      
 
      - 
        30 mg/1300mg MNK-795 (high dose, intact)
      
 
      - 
        30 mg/1300mg Percocet (high dose, intact)
      
 
      - 
        Crushed, encapsulated high dose MNK-795
      
 
      - 
        Crushed, encapsulated high dose Percocet
      
 
    
      The study evaluated the subjective effects that have been associated
      with drug abuse. The primary outcome measures were 100-point VAS of
      subject-reported drug liking, drug high, and good drug effects. The most
      common adverse events associated with the use of MNK-795 included
      nausea, vomiting, and pruritus (itching).
    
      Percocet is a registered trademark of Endo Pharmaceuticals Inc.
    
      ABOUT MALLINCKRODT
    
      Mallinckrodt is a leading global specialty pharmaceuticals business that
      develops, manufactures, markets, and distributes specialty
      pharmaceutical products and medical imaging agents. The Company’s
      Specialty Pharmaceuticals segment includes branded and generic drugs,
      and the Global Medical Imaging segment includes contrast media and
      nuclear imaging agents. Mallinckrodt has approximately 5,500 employees
      worldwide with direct sales in roughly 50 countries and distribution in
      approximately 40 other countries. The Company’s 2012 revenue totaled
      $2.1 billion. To learn more about Mallinckrodt, visit www.mallinckrodt.com.
    
      FORWARD-LOOKING STATEMENTS
    
      Any statements contained in this communication that do not describe
      historical facts may constitute forward-looking statements as that term
      is defined in the Private Securities Litigation Reform Act of 1995. Such
      forward-looking statements include, but are not limited to, statements
      about future financial condition and operating results, economic,
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      Any forward-looking statements contained herein are based on our
      management's current beliefs and expectations, but are subject to a
      number of risks, uncertainties and changes in circumstances, which may
      cause actual results or Company actions to differ materially from what
      is expressed or implied by these statements. The factors that could
      cause actual future results to differ materially from current
      expectations include, but are not limited to, our ability to receive
      procurement and production quotas granted by the U.S. Drug Enforcement
      Administration, our ability to obtain and/or timely transport
      molybdenum-99 to our technetium-99m generator production facilities,
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Source: Mallinckrodt
      Mallinckrodt
Lynn Phillips, 314-654-3263
Manager, Media
      Relations
lynn.phillips@mallinckrodt.com
or
Meredith
      Fischer, 314-654-6595
Senior Vice President, Communications
meredith.fischer@mallinckrodt.com
or
John
      Moten, 314-654-6650
Vice President, Investor Relations
john.moten@mallinckrodt.com