section_path: Treatment and management/Medication/Research
section_name: Research
paragraph_text: Research
  
  Anti-drug vaccines (active immunizations) for treatment of cocaine and nicotine addictions were successful in animal studies. Vaccines tested on humans have been shown as safe with mild to moderate side effects, though did not have firm results confirming efficacy despite producing expected antibodies. Vaccines which use anti-drug monoclonal antibodies (passive immunization) can mitigate drug-induced positive reinforcement by preventing the drug from moving across the blood–brain barrier. Current vaccine-based therapies are only effective in a relatively small subset of individuals. As of November 2015, vaccine-based therapies are being tested in human clinical trials as a treatment for addiction and preventive measure against drug overdoses involving nicotine, cocaine, and methamphetamine. The study shows that the vaccine may save lives during a drug overdose. In this instance, the idea is that the body will respond to the vaccine by quickly producing antibodies to prevent the opioids from accessing the brain.
  
  Since addiction involves abnormalities in glutamate and GABAergic neurotransmission, receptors associated with these neurotransmitters (e.g., AMPA receptors, NMDA receptors, and GABA receptors) are potential therapeutic targets for addictions. N-acetylcysteine, which affects metabotropic glutamate receptors and NMDA receptors, has shown some benefit involving addictions to cocaine, heroin, and cannabinoids. It may be useful as an adjunct therapy for addictions to amphetamine-type stimulants, but more clinical research is required.
  
  Current medical reviews of research involving lab animals have identified a drug class – class I histone deacetylase inhibitors – that indirectly inhibits the function and further increases in the expression of accumbal ΔFosB by inducing G9a expression in the nucleus accumbens after prolonged use. These reviews and subsequent preliminary evidence which used oral administration or intraperitoneal administration of the sodium salt of butyric acid or other class I HDAC inhibitors for an extended period indicate that these drugs have efficacy in reducing addictive behavior in lab animals that have developed addictions to ethanol, psychostimulants (i.e., amphetamine and cocaine), nicotine, and opiates. Few clinical trials involving humans with addictions and any HDAC class I inhibitors have been conducted to test for treatment efficacy in humans or identify an optimal dosing regimen.
  
  Gene therapy for addiction is an active area of research. One line of gene therapy research involves the use of viral vectors to increase the expression of dopamine D2 receptor proteins in the brain.