FDA Approves Monthly Injection for Alcohol Dependence
Topics: Addiction Medicine | Treatment Populations > Medication Assisted
Treatment

2006-05-06 | By Peggy Peck, Senior Editor, MedPage Today



CAMBRIDGE, Mass., April 13 - The FDA has approved a monthly injectable
formulation of Vivitrol (naltrexone for extended-release) for treatment of
alcohol-dependent patients, the drug marketers, Alkermes and Cephalon,
announced today.
The drug, intended for use by outpatients who are not actively drinking,
should be used in combination with psychosocial support, the announcement
said.

The companies said they will market the drug in 380 mg IM doses and expect
the product to be available by June.

"Vivitrol is the first once-a-month medication for alcohol dependence that
ensures patients get the benefit of medication over the entire month," said
Richard Rosenthal, M.D., chairman, of psychiatry at St.
Luke's-Roosevelt Hospital Center in New York, in the companies'
statement.

Vivitrol binds opioid receptors in the brain and preclinical data suggest
that binding results in blockade of neurotransmitters that promote alcohol
dependence. That blockade is thought to be the mechanism by which Vivitrol
reduces alcohol consumption in treated patients.

In a six-month phase III trial, patients treated with Vivitrol (380 mg) and
psychosocial support demonstrated a reduction in days of heavy drinking
compared with patients treated with placebo and psychosocial support.

In a subset of patients who were abstinent for a week before starting
Vivitrol treatment, the drug was associated with continued abstinence in a
significant number of patients (without relapse). Moreover, patients who
were abstinent before receiving the initial injection of Vivitrol had a
greater reduction in drinking days and heavy-drinking days.

Although Vivitrol was generally well tolerated, with the most common side
effects being nausea, vomiting, headache, fatigue, and injection site
rejections, high doses of naltrexone have been reported to cause
hepatocellular injury.

The drug was contraindicated in patients with acute hepatitis or liver
failure, and its "use in patients with active liver disease must be
carefully considered in light of its hepatotoxic effects." But the company
said that at recommended doses Vivitrol does not appear to be hepatoxic.

"Patients should be warned of the risk of hepatic injury and advised to seek
medical attention if they experience symptoms of acute hepatitis,"
the companies said.

Vivitrol is contraindicated in patients receiving opioid analgesics.
Likewise, it is contraindicated in opioid-dependent patients and patients
undergoing opioid withdrawal.