Some of the most intriguing research into addiction treatment being done today is with vaccines. The idea is rather simple. Drugs of abuse pass through the blood-brain barrier because they are too small, too simple to be targeted by the immune system. So researchers have designed vaccines that take key fragments of the drug molecules and attach them to larger, more immune-provoking carriers (such as a cholera toxin or a tetanus toxin). The antibodies produced by this work-around will attack the drug and prevent it from passing through the blood-brain barrier and reaching the reward pathway in the brain. In other words, you can ingest the drug BUT WON’T GET HIGH!
Vaccines are being developed for drugs of abuse like alcohol, marijuana, heroin, methamphetamine, nicotine, and cocaine. A previous blog post, “Raising the Stakes in the War on Cocaine Addiction,” looked at the attempts to develop a cocaine vaccine by Thomas Kosten. His research has developed to the stage of clinical trials with humans, but a concern was discovered. Some of the human participants used ten times as much cocaine while attempting to override the blocking action of the cocaine vaccine. That trick could kill an individual who tried it with heroin.
Heroin has been a moving target for vaccine research because it quickly degrades into 6-acetylmorphine (6AM) and morphine. Kim Janda and his team of researchers associated with The Scripps Research Institute have developed a “dynamic vaccine” that creates antibodies against heroin and its psychoactive metabolites. You can read the academic journal article on their work found in the Proceedings of the National Academy of Sciences here or a summary of their research on The Scripps Research Institute website here or here.
There are positives and negatives to Janda’s dynamic heroin vaccine. First, while it will attach to heroin and its metabolites, it won’t work with oxycodone (OxyContin) or hydrocodone (Vicodin, Zohydro); or any other opioid. This is a trade-off because of the above-mentioned rapid degradation of heroin into its psychoactive metabolites. Second, this means the dynamic vaccine also won’t work with methadone or buprenorphine (Suboxone, Subutex), which are both opioids. So it can be used in conjunction with opioid maintenance therapy.
Although Janda’s research suggested that his vaccine helped limit heroin seeking behavior and halted the progression of compulsive heroin taking with rats, there are easy work-arounds for human beings. A human addict could ingest oxycodone or hydrocodone while taking the heroin vaccine to get high. They could even take a benzodiazepine along with their methadone or Suboxone for a nice, heroin-like buzz while taking the Janda vaccine. These limitations were acknowledged by Janda’s research team: “Although the dynamic heroin vaccine is not targeted to treat the ‘addicted’ brain, it represents a robust tool in the continuous blockade of all heroin activity.” In the concluding paragraph of the journal article, the research team said:
The prospect of heroin vaccine use in the treatment of addiction presents a high-payoff, low-risk opportunity. Drug vaccination requires minimal medical monitoring and compliance to maintain opiate resistance, allowing for greater potential worldwide accessibility. Furthermore … drug vaccines represent a low risk for long-term side effects. . . . Although it may not be a “magic bullet” against all aspects of drug addiction, the dynamic nature of our heroin vaccine represents a promising and innovative adjunct therapy in the treatment of heroin addiction.
But Janda’s research is stalled because it ran out of funding. In an interview with The Fix, he said: “We are not anywhere near human trials because nobody wants to pay for them.” Earlier funding was obtained by the Scripps Research Institute, the Pearson Center for Alcoholism and Addiction Research and the National Institute of Health (NIH). Janda and others have approached the NIH for additional funding, but so far have been unsuccessful.
Pharmaceutical companies aren’t interested either. Janda commented: “I have talked to many different companies and not one has shown any interest whatsoever. They don’t feel there is value for their company.” He doesn’t understand this from the standpoint of the greater good of society, but will attempt the route of applying for more research grants from the government. “I think we’ll probably just have to keep going it alone.”
I have mixed feelings about this vaccine, not because of the research, but because of what I know about how some addicts think. The research from the cocaine vaccine clinical trails discussed above noted how some addicts tried to test the vaccine with ten times as much cocaine as they usually ingested to get high. If heroin addicts test Janda’s heroin vaccine in a similar way, they will be risking their lives. It will be like playing Russian roulette with heroin.
There is also an “addiction” to the ritual of getting high (tying off, cooking the heroin, etc) for some addicts that the vaccine will not touch. I’ve known heroin addicts under the influence of this kind of obsession who compulsively “shoot up” water attempting to satisfy this urge. As Janda himself said, while it will blockade all heroin activity, it is not targeted to treat the “addicted brain.”
