News Release

Mallinckrodt Pharmaceutical’s MNK-155, an Extended-Release Hydrocodone/Acetaminophen Combination, Shows Efficacy in Phase 3 Acute Pain Trial

MNK-155 (hydrocodone bitartrate/acetaminophen) demonstrated significantly greater pain reduction than placebo following bunion surgery

LAS VEGAS--(BUSINESS WIRE)--Sep. 4, 2014-- Mallinckrodt (NYSE: MNK) today reported that a Phase 3 efficacy trial of investigational MNK-155 met the study’s primary endpoint of improved pain scores vs. placebo over the first 48 hours following bunionectomy (p<0.001). This difference in pain scores was statistically significant in favor of MNK-155. The data is being presented at PAINWeek 2014, a national conference on pain for frontline practitioners, held in Las Vegas, Nevada September 2-6, 2014.

MNK-155 is an investigational extended-release oral formulation of hydrocodone and acetaminophen being studied for the management of moderate to moderately severe acute pain where the use of an opioid analgesic is appropriate. MNK-155 is formulated with both immediate- and extended-release components. The release profile of MNK-155 combines Mallinckrodt-proprietary, patented technology and Depomed’s advanced Acuform® drug delivery technology. The NDA for MNK-155 was accepted for review by the U.S. FDA in May 2014 and included results from this study.

“In this study, MNK-155 showed rapid, significant and superior pain relief to placebo with a 12-hour dosing interval throughout the 48-hour study period,” said Dr. Mario Saltarelli, Chief Science Officer, Mallinckrodt Pharmaceuticals. “These positive Phase 3 findings are great news as we strive to develop new medications with less frequent dosing for patients with acute pain.”

In addition to the Phase 3 study, Mallinckrodt will present data at PAINWeek from several other MNK-155 trials, including the pharmacokinetics, safety and subjective effects of abuse-related characteristics.

Study Details

The Phase 3 trial was a multicenter, randomized, double-blind, placebo-controlled, parallel-arm study comparing the efficacy and safety of MNK-155 and placebo in 403 patients with moderate to moderately severe acute pain following a unilateral first metatarsal bunionectomy. Subjects received a single 3-tablet loading dose of MNK-155 (7.5 mg hydrocodone and 325 mg acetaminophen tablets; 22.5 mg/975 mg total dose), followed by 2 tablets every 12 hours (15 mg /650 mg total dose) over 48 hours or placebo. Rescue ibuprofen up to 400 mg every 4 hours was allowed for both the MNK-155 and placebo arms.

The primary endpoint was the summed pain intensity difference (change in pain from baseline) over 48 hours (SPID48). Secondary measures included: Cumulative SPID at 0−4, 0−8, 0−12, 0−24, and 0−36 hours; mean PID beginning 15 minutes after dosing, mean total pain relief (TOTPAR) for the time periods 0−4, 0−8, 0−12, 0−24, 0−36, and 0−48 hours; and time to perceptible, confirmed, and meaningful pain relief. The most common adverse events associated with the use of MNK-155 were nausea, dizziness, vomiting, headaches, constipation, pruritus and somnolence (sleepiness).

About Mallinckrodt

Mallinckrodt is a global specialty pharmaceutical and medical imaging business that develops, manufactures, markets and distributes specialty pharmaceutical products and medical imaging agents. Areas of focus include analgesics and central nervous system drugs for prescribing by office- and hospital-based physicians, and autoimmune and rare disease specialty areas like neurology, rheumatology, nephrology and pulmonology. The company's core strengths include the acquisition and management of highly regulated raw materials; deep regulatory expertise; and specialized chemistry, formulation and manufacturing capabilities. The company's Specialty Pharmaceuticals segment includes branded and specialty generic drugs and active pharmaceutical ingredients, and the Global Medical Imaging segment includes contrast media and nuclear imaging agents. Mallinckrodt has more than 5,500 employees worldwide and a commercial presence in roughly 65 countries. The company's fiscal 2013 revenue totaled $2.2 billion. To learn more about Mallinckrodt, visit

Source: Mallinckrodt

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