FDA has sanctioned Alkermes’ Vivitrol to treat and prevent relapse after patients with opioid dependence have undergone detoxification treatment. Vivitrol is the first non-narcotic, nonaddictive, once-monthly medication approved in this indication, according to Alkermes.
Vivitrol is an extended-release formulation of naltrexone administered by intramuscular injection once a month.
Naltrexone works to block opioid receptors in the brain. It prevents the effects of drugs like morphine, heroin, and other opioids. It was approved to treat alcohol dependence in 2006.
The safety and efficacy of Vivitrol were studied for six months, comparing Vivitrol to placebo in patients who had completed detoxification and who were no longer physically dependent on opioids. Patients treated with Vivitrol were more likely to stay in treatment and to refrain from using illicit drugs, according to the FDA. Thirty-six percent of the Vivitrol-treated patients were able to stay in treatment for the full six months without using drugs, compared with 23% in the placebo group.
Patients must not have any opioids in their system when they start taking Vivitrol; otherwise, they may experience withdrawal symptoms from the opioids. Also, patients may be more sensitive to opioids while taking Vivitrol at the time their next scheduled dose is due. If they miss a dose or after treatment with Vivitrol has ended, patients can accidentally overdose if they restart opioid use.
Side effects experienced by those using Vivitrol included nausea, tiredness, headache, dizziness, vomiting, decreased appetite, painful joints, and muscle cramps. Other serious side effects included reactions at the site of the injection, which can be severe and may require surgical intervention, liver damage, allergic reactions such as hives, rashes, swelling of the face, pneumonia, depressed mood, suicide, suicidal thoughts, and suicidal behavior.
Alkermes has one more dependence-related drug, which is at the Phase II stage. ALKS 33 is an oral opioid modulator in development for the treatment of reward disorders. In November 2009, the company initiated a mid-stage study of ALKS 33 in alcohol-dependent patients. In April 2010, Alkermes reported further development plans as a treatment of binge eating disorder and as a combination therapy with buprenorphine for the treatment of addiction and mood disorders.
Opioid modulators are thought to have a number of clinical applications including the treatment of central nervous system disorders and impulse-control disorders. ALKS 33 has been shown to be generally well tolerated and demonstrated rapid oral absorption, high plasma concentrations, and duration of action that supports once daily dosing.