Vivitrol Monthly Shot Approved for Opioid Dependence

Oct. 13, 2010— -- The U.S. Food and Drug Administration has given the go-ahead to a once-monthly injection to treat opioid dependence, the agency said Tuesday.

Vivitrol, a long-acting formulation of naltrexone (ReVia), is already approved as a monthly shot to treat alcohol dependence. The new indication puts Vivitrol on a list of pharmacologic treatments for addiction -- a list that already includes methadone and buprenorphine.

"We are always happy to have another addition to our arsenal of addiction treatment," said Dr. Petros Levounis of St. Luke's and Roosevelt Hospitals in New York City.

"Addiction is a serious problem in this country, and can have devastating effects on individuals who are drug-dependent, and on their family members and society," Dr. Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, said in a statement. "This drug approval represents a significant advancement in addiction treatment."

Vivitrol and naltrexone are opioid antagonists, which block the brain's opioid receptors, leaving patients at a loss of feeling if they attempt to abuse opioids.

That differs from methadone, an opioid agonist used as replacement therapy, and buprenorphine, a partial agonist that blocks most opioid receptors while giving the patient just a taste of opioid.

Vivitrol, like naltrexone and buprenorphine, can be prescribed by a primary care physician.

Earlier data reported at the American Psychological Association meeting last May found that 90 percent of patients on Vivitrol had opioid-free urine screens over a six-month period, compared with 35 percent of those on a placebo injection.

The FDA said it relied on data from other studies, which found that 36 percent of Vivitrol patients stayed on treatment for six months, compared with 23 percent of placebo patients.

The agency said serious side effects include injection site reaction that requires surgical intervention and liver damage.

Other side effects could include depression, suicide, suicidal thoughts and behaviors, although the treatment will not include any boxed warnings.

According to drug maker Alkermes, about 10,000 patients per year currently use Vivitrol to treat alcohol dependence, a treatment strategy approved in April 2006.

The drug has not had widespread uptake for that indication for a number of reasons, the company said. Many physicians are wary of treating patients with abuse disorders, and patients more often reach out for psychosocial counseling to beat their habits, such as 12-step programs.

Researchers say these factors explain the slow uptake of many of the other pharmacological treatments for addiction.

Last month, an FDA advisory committee voted 12-1 to approve Vivitrol to treat opioid abuse.