A few days ago I talked about a possible cousin of buprenorphine, Lofexidine, that may be hitting the market soon. Well, a new member of the opiate addiction treatment family may also be making an appearance in the near future because the phase 3 clinical trials for a drug called Vivitrol with the intent of ascertaining its efficacy in treating opioid dependence are set to begin.

What is Vivitrol?

Alkermes, Inc., is the biotech company that manufactures Vivitrol, a drug approved by the U.S. Food and Drug Administration in April 2006 for the treatment of alcohol dependence.

So Why Does Alkermes Think Vivitrol Might Work in Opiate Addiction Treatment?

Dr. Herbert Kleber is a professor of psychiatry and director of the Division on Substance Abuse at Columbia University. He says:

“Opioid dependence is a serious disease affecting millions of people yet there are few approved medications available for these patients and no approved long-acting antagonist therapies. Naltrexone, the active ingredient in VIVITROL, has been shown to effectively block the effects of opiates but patients have difficulty complying with a daily medication regimen. Therefore, I am pleased to see the development of new therapeutic options, such as VIVITROL, which could provide an important approach to long-term recovery and potentially help reduce the risk of relapse.”

The Need for Opiate Addiction Treatment

Opiate addiction is a growing problem in the United States and encompasses the physical dependence upon and nonmedical abuse of drugs ranging from heroin, which is illegal in any context, to opioid-based prescription pain relievers. There are almost 2 million people over the age of 12 in this country alone who abuse opiates, according to the 2006 U.S. National Survey on Drug Use and Health. In Europe, that number is slightly lower, ranging between 1.3 million to 1.7 million people according to the European Monitoring Centre for Drugs and Drug Addiction in 2005.

Dr. Elliot Ehrich is the Chief Medical Officer of Alkermes and says, “If approved, VIVITROL would be the first and only non-narcotic, non-addictive, long-acting medication for the treatment of opioid dependence.”

That’s if Lofexidine doesn’t get there first!
For more information on this and other studies pertaining to opiate addiction and opiate addiction treatment, check out Medical News Today.

US WorldMeds is a Kentucky-based specialty pharmaceutical company and they have recently completed Phase III clinical trials of lofexidine hydrochloride (Lofexidine) in the treatment of opiate addiction. More specifically, Lofexidine would treat the withdrawal symptoms associated with opiate detox just like buprenorphine and methadone. So is there a new treatment in the world of opiate addiction? According to Medical News Today, “opiate-dependent patients taking the drug experienced a significant reduction in withdrawal symptoms at the anticipated peak of withdrawal and stayed longer in detoxification treatment as compared to patients taking placebo.”

The Hope of a New Option for Opiate Addiction

Paul Breckinridge “Breck” Jones is the CEO of US WorldMeds. He says, “The debilitating withdrawal symptoms associated with opiate detoxification are a major reason people struggling with heroin or prescription drug addiction avoid or leave treatment. These trial results are impressive and confirm our expectations for Lofexidine. Lofexidine promises to be an important new tool for treating opiate addiction here in the US.”

The Difference Between Lofexidine and Buprenorphine

From what I can tell, the biggest difference is that Lofexidine is non-addictive and non-narcotic, unlike buprenorphine which works because it is an opiate with a high affinity for the opiate receptors that require constant engagement when you are an opiate addict. So Lofexidine is more of a treatment for the withdrawal symptoms than it is for the addiction. It eases the vomiting and nausea, stomach and muscle cramps, cold sweats and insomnia.

What This Could Mean to Opiate Addiction Treatment

Lofexidine is not yet approved by the US Food and Drug Administration (FDA) so this is purely speculation, but if the drug were to be approved, it would be the only non-narcotic treatment available for treating opiate withdrawal symptoms. According to Medical News Today,

“Lofexidine has been approved for use for 15 years in the United Kingdom (UK) to manage the often debilitating withdrawal symptoms that occur during opiate detoxification.

“Given the encouraging initial results of the Phase III clinical trial, US WorldMeds intends to submit a new drug application (NDA) for Lofexidine with the FDA for US approval. The NDA will be filed after the complete dataset from the trial, including additional efficacy and safety measures, is analyzed, and additional required studies are completed.”

What do you think?

I can’t stop thinking about it. The other day we talked about a guy on buprenorphine who saved up his pills and tried to return to maintenance after a heroin relapse by taking 11 8-milligram pills only to find himself smack in the middle of a nasty opiate withdrawal.

If he took Suboxone—a combination of buprenorphine and naloxone—without waiting for withdrawal symptoms to kick in first, then that makes sense. When you’re already strung out on prescription painkillers or heroin and are ready to detox, the doctor will most likely start you on Subutex first or wait for withdrawal to start before switching you over to Suboxone with the express purpose of helping you avoid an onslaught of withdrawal symptoms. According to the Associated Press article, this man continued to take buprenorphine after the first handful of pills and yet the symptoms still did not subside.

What The Experts Have to Say

In the article, they have this comment:

“When buprenorphine is taken soon after opiates with less opiate-receptor affinity, such as heroin and methadone, it displaces them from the receptors. Since buprenorphine is only a partial agonist, this causes a drop in the level of overall opiate activity and is experienced as opiate withdrawal. While we are aware of only three other reported cases of buprenorphine-precipitated withdrawal after heroin use, it is common in methadone patients transferring to buprenorphine therapy, particularly with higher doses of methadone (> 40 mg), a short time between the last methadone dose and the first buprenorphine dose and when higher initial buprenorphine doses are used. Withdrawal symptoms typically commence within 1–3 hours of the first buprenorphine dose and can last for several days.”

What This Case Shows About Buprenorphine

First, it shows that you can take 88 milligrams of the drug and not die. The highest dose prescribed is 32 milligrams, so that’s almost three times as much, and there was no respiratory depression to speak of. Considering that’s the problem with opiate overdose, that’s good news for those on buprenorphine who can’t be rescued from respiratory depression by naloxone. So here’s more evidence on the ceiling effect of buprenorphine, that you don’t “feel it” per se even when you increase your dose. I’ve heard people say that it doesn’t feel like they’re taking anything at all, no matter what dose they’re at.

This case also shows that repeated doses of buprenorphine doesn’t help matters any, since his withdrawal symptoms didn’t subside with multiple doses. Maybe his dose of heroin was too high. And his initial dose of buprenorphine was definitely too high. But this, too, is an interesting fact to ponder.

Okay…. Discuss!