Mallinckrodt has reported data from a Human Abuse Liability (HAL) study in which both intact and crushed MNK-155 showed lower subjective abuse-related effects than an immediate-release hydrocodone bitartrate/acetaminophen formulation (a generic form of Vicodin®). The data was presented at PAINWeek 2014.

In the HAL study, intact and crushed MNK-155 demonstrated statistically significant (p <0.001) lower measures of drug liking, drug high and good drug effects compared with comparable doses of intact immediate-release hydrocodone bitartrate/acetaminophen when measured at the peak drug effect (Emax). It also took significantly longer for intact and crushed MNK-155 to reach peak drug effect compared with intact immediate-release hydrocodone bitartrate/acetaminophen for each of these three measures (p ≤0.029).

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 and was recently awarded patent protection covering its unique design, formulation, pharmacokinetic, and release characteristics. The NDA for MNK-155 was accepted for review by the U.S. Food and Drug Administration (FDA) in May 2014.

"All patients experience pain differently, and there is no 'one size fits all' approach to acute pain treatment. It is essential that patients who warrant treatment for legitimate acute pain have options and access to appropriate pain medications prescribed by a physician," said Dr. Lynn Webster, Vice President, Scientific Affairs, PRA HEALTH SCIENCES. "The HAL study data of MNK-155 presented at PAINWeek are encouraging and warrant further study of this formulation."

HAL studies are included in the FDA's Guidance for Industry: Abuse-Deterrent Opioids - Evaluation and Labeling (January 2013). 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.

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 orally-administered MNK-155 in 52 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
  • 22.5 mg/975 mg MNK-155 (low dose, intact)
  • 22.5 mg/975 mg immediate-release hydrocodone bitartrate/acetaminophen formulation (low dose, intact)
  • 45 mg/1950mg MNK-155 (high dose, intact)
  • 45 mg/1950mg immediate-release hydrocodone bitartrate/acetaminophen formulation (high dose, intact)
  • Crushed, encapsulated high dose MNK-155
  • Crushed, encapsulated high dose immediate-release hydrocodone bitartrate/acetaminophen formulation

The study evaluated certain 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, with intact and crushed MNK-155 demonstrating statistically significant (p <0.001) lower measures, compared with comparable doses of intact immediate-release hydrocodone bitartrate/acetaminophen when measured at the peak drug effect (Emax). It also took significantly longer for intact and crushed MNK-155 to reach peak drug effect compared with intact immediate-release hydrocodone bitartrate/acetaminophen for each of these three measures (p ≤0.029). The most common adverse events associated with the use of MNK-155 included nausea, vomiting, pruritus, headache and dizziness.

Vicodin® is a registered trademark of Abbvie Inc.