A high-tech solution?

Will we one day be vaccinating against drugs and alcohol?

While there are some treatments available for recovering addicts, relapse rates are still predicted to be around 50 per cent, with rates for cocaine and heroin users being over 80 per cent in the first five years. So there is a push for more effective treatments. For some addictions, trials are underway with vaccines that block the actions of drugs.

The idea is that these vaccines would make the patient’s immune system generate antibodies that would stick to the drug molecules, and slow or even prevent their entry into the brain. The drug would then be broken down naturally in the body – the liver breaks down nicotine and methamphetamine and an enzyme called cholinesterase breaks down cocaine. Like pharmacological treatments, this approach would aim to treat the physical addiction rather than any psychological aspects. Patients would still experience withdrawal symptoms, but they might be less likely to relapse as the drug would be less effective in providing a high.

A nicotine vaccine failed in recent clinical trials, but that isn’t the end of the story. Researchers have found the root of the problem and believe they can now make steps to improve the vaccine. Nicotine can exist in two molecular forms, ‘left-handed’ and ‘right-handed’ – and 99 per cent of nicotine in tobacco is left-handed. The previous vaccine trial tried to create antibodies against both types. In a recent study in rats, vaccines aimed only at the left-handed form were more effective than the mixed (left- and right-handed) version.

Nicotine isn’t the only target of such drugs – scientists want to use this technique for cocaine and heroin too. One vaccine being developed for cocaine has been tested in primates, and has lowered the amount of cocaine able to bind to receptors to 20 per cent (below the 47 per cent threshold needed for experiencing a high).

Some scientists worry that a vaccine that prevents highs at low substance doses may lead the patient to increase the amount of substance they take, to overcome the vaccine. These vaccines may only be viable for people who are committed to recovery, and may need to be used in conjunction with therapy to make sure any psychological aspects of the addiction are being considered.


Further reading

About this resource

This resource was first published in ‘Addiction’ in June 2010 and reviewed and updated in September 2015.

Education levels:
16–19, Continuing professional development