Vivitrol, which is an injectable form of extended-release naltrexone, approved by the FDA last week, could be on the market as soon as June 2006.
Naltrexone has been used for several years to help reduce craving by binding to opioid receptors in the brain, blocking the neurotransmitters that are associated with alcohol dependence.
Until now it has only been available in a pill, which has to be taken daily, which produced problems of patients adhering to the daily-dose routine. The effectiveness of the Vivitrol monthly injections have been shown to last the entire month.
In clinical trials of the new month injection form of the drug, patients who received Vivitrol and psychosocial support experienced greater reduction in days of heavy drinking than those who received only psychosocial support and placebo injection.
Patients who abstained from drinking in the week prior to the treatment with Vivitrol were more likely to maintain complete abstinence over six months and experienced a greater reduction both in drinking days and heavy drinking days.
Vivitrol will be available by prescription and administered by healthcare professionals. It should not be taken by patients who have already experienced liver damage or liver failure.
Vivitrol was developed and manufactured by Alkermes, Inc. It will be marketed in the United States by Cephalon. The company expects sales of the new drug to be between $300 and $500 million annually.