Zohydro (hydrocodone bitartrate) Development Status

Zohydro Phase 3 Clinical Development Program

We initiated a single pivotal Phase 3 efficacy trial (Study 801) in March 2010. This trial is a randomized, 12-week, double-blind, placebo-controlled trial to evaluate the safety and efficacy of Zohydro for the treatment of moderate to severe chronic lower back pain in opioid-experienced adult subjects. Our trial utilizes a protocol design that has been used successfully to demonstrate the efficacy of other extended-release opioid therapies for chronic pain. The primary efficacy endpoint in this trial is the mean change in average daily pain intensity scores between ZX002 and placebo.

To further assess the safety and tolerability of Zohydro as a chronic pain therapy, we have also initiated an open-label Phase 3 trial in opioid-experienced adult subjects with any indication appropriate for continuous, around-the-clock opioid therapy for an extended period of time (Study 802). The goal of this trial is to evaluate the safety and tolerability of Zoydro for up to 12 months of treatment.

Prior Clinical Development of Zohydro

Our licensor for Zohydro, Elan Pharma International Limited, conducted pre-clinical and clinical studies of Zohydro under an IND initiated in 2002.

Phase 1 and Phase 2 Clinical Development. In single and multiple dose pharmacokinetic evaluations, ZX002 demonstrated a consistent, controlled-release profile, dose-proportional pharmacokinetics and an acceptable safety profile.

Zohydro has also been evaluated in two separate Phase 2 pain studies. We believe this efficacy and safety information is useful in establishing proof-of-concept for Zohydro. In both Phase 2 studies, patients experienced mild to moderate adverse events, such as dizziness, sedation, nausea, vomiting and constipation, which are similar to the reported effects of opioids currently prescribed for chronic pain.