As expected, regulators in the USA have given the green light to Alkermes' alcoholism drug Vivitrol as a treatment for addiction to opioid drugs.

The US Food and Drug Administration has approved Vivitrol (naltrexone for extended-release injectable suspension) for the prevention of relapse to opioid dependence, following detoxification. The expanded approval means the once-a-month medication is the first non-narcotic, non-addictive drug to get the thumbs-up for this condition.

The approval comes a month after the FDA's Psychopharmacologic Drugs Advisory Committee voted 12 to 1 that Vivitrol should be approved, having been available for alcohol dependence since 2006. Janet Woodcock, director of FDA’s Center for Drug Evaluation and Research, noted that "addiction is a serious problem" in the USA, "and can have devastating effects on individuals who are drug-dependent, and on their family members and society”. She added that “this drug approval represents a significant advancement in addiction treatment".

The safety and efficacy of the drug were studied for six months, comparing Vivitrol to placebo who had completed detoxification and who were no longer physically dependent on opioids. Some 36% of the Vivitrol-treated patients were able to stay in treatment for the full six months without using drugs, compared with 23% on placebo.

Alkermes noted that in contrast to existing therapies, ie methadone and Suboxone (buprenorphine and naloxone), which are opioid narcotics themselves and considered ‘replacement therapies,’ Vivitrol blocks the opioid receptors in the brain that drive addiction, instead of activating them like the aforementioned products.

The company added that Vivitrol can be "prescribed by any physician and administered in the doctor’s office" in contrast to methadone or Suboxone which are dispensed at specific clinics or addiction specialists. It concluded by saying that the once-monthly injection "eliminates the burden or challenge of taking a daily medication by a patient seeking to overcome addiction".

The expanded approval is a major boost for Alkermes which has had trouble making money from Vivitrol for alcohol dependence, hurt by price and access problems.