Alkermes, Inc. (NASDAQ: ALKS) today announced positive preliminary results from a phase 3 clinical trial of naltrexone for extended-release injectable suspension (XR-NTX) for the treatment of opioid dependence. The six-month phase 3 study met its primary efficacy endpoint and data showed that patients treated once-monthly with XR-NTX demonstrated statistically significant higher rates of clean (opioid-free) urine screens, compared to patients treated with placebo, as measured by the cumulative distribution of clean urine screens (p<0.0002). Based on the positive results of this phase 3 study, Alkermes plans to file a supplemental New Drug Application (sNDA) with the U.S. Food and Drug Administration (FDA) in the first half of calendar 2010. XR-NTX, marketed by Alkermes as VIVITROL®, is an opioid antagonist administered once-monthly by intramuscular injection and is approved in the U.S. for the treatment of alcohol dependence. If approved by the FDA for the treatment of opioid dependence, XR-NTX has the potential to be the first and only non-narcotic, non-addictive drug agent available in a once-monthly formulation.
In addition to meeting the primary efficacy endpoint, the six-month phase 3 study met all secondary efficacy endpoints. Data from the intent-to-treat (ITT) analysis show that the median patient taking XR-NTX had 90% opioid-free urine screens during the evaluation phase of the study and patients treated with XR-NTX demonstrated a significant reduction in opioid craving compared to placebo as measured by a visual analog scale. XR-NTX was generally well tolerated in the study and no patients on XR-NTX discontinued the study due to adverse events. The most common adverse events experienced by patients receiving XR-NTX during the study were nasopharyngitis and insomnia.
“These robust data show that XR-NTX helped opioid dependent patients become drug-free with just one injection each month,” stated Dr. Herbert Kleber, Professor of Psychiatry, Director, Division on Substance Abuse, Columbia University. “XR-NTX is a unique formulation that offers patients and physicians a once-monthly, non-addictive medication to help fight this challenging disease.”
“Medical treatment for opioid dependence is an established and growing pharmaceutical market, yet there are limitations with currently available therapies," stated Richard Pops, Chief Executive Officer of Alkermes. “We look forward to expanding our label beyond alcohol dependence to make XR-NTX available as the first and only non-narcotic, non-addictive, once-monthly treatment option for the millions of patients struggling with opioid dependence.”
Alkermes will complete the full analysis of the phase 3 trial data and plans to submit the data for publication in a peer-reviewed journal.