Substance Abuse News

Researchers have produced a lasting anti-cocaine immunity in mice by giving them a safe vaccine that combines bits of the common cold virus with a particle that mimics cocaine.

In their study, published in the online edition of Molecular Therapy and funded by the National Institute on Drug Abuse, the researchers say this novel strategy might be the first to offer cocaine addicts a fairly simple way to break and reverse their habit, and it might also be useful in treating other addictions, such as to nicotine, heroin and other opiates.

Fighting Cocaine Addiction

“Our very dramatic data shows that we can protect mice against the effects of cocaine, and we think this approach could be very promising in fighting addiction in humans,” says the study’s lead investigator, Dr. Ronald G. Crystal, chairman and professor of genetic medicine at Weill Cornell Medical College.

He says the antibody immune response produced in lab mice by the vaccine binds to, and sequesters, cocaine molecules before the drug reached the brains of these animals — and prevents any cocaine-related hyperactivity. The vaccine effect lasted for at least 13 weeks, the longest time point evaluated.

“While other attempts at producing immunity against cocaine have been tried, this is the first that will likely not require multiple, expensive infusions, and that can move quickly into human trials,” Dr. Crystal says. “There is currently no FDA-approved vaccine for any drug addiction.”

“An approach that works is desperately needed for cocaine addiction, which is an intransigent problem worldwide,” he adds. “There are no therapies now.”

The novelty of this possible treatment is that it hooks a chemical that is very similar in structure to cocaine, onto components of the adenovirus, a common cold virus. In this way, the human immune system is alerted to an infectious agent (the virus) but also learns to “see” the cocaine as an intruder as well, Dr. Crystal says. Once the structure of the new intruder is recognized, natural immunity builds to cocaine particles, so any time cocaine is snorted or used in any way, antibodies to the substance are quickly produced and the cocaine molecules are engulfed by the antibodies and prevented from reaching the brain.

Engineering a New Response

“The human immune system doesn’t naturally tag cocaine as something to be destroyed — just like all small-molecule drugs are not eliminated by antibodies,” he says. “We have engineered this response so that it is against the cocaine mimic.”

In this study, a team of researchers — scientists from Weill Cornell Medical College, Cornell University in Ithaca, and the Scripps Research Institute in La Jolla, Calif. — ripped apart an adenovirus, retrieving only the components that elicit an immune response and discarding those that produce sickness. They then hooked the cocaine analog on to these proteins to make the vaccine. “We used the cocaine analog because it is a little more stable than cocaine, and it also elicits better immunity,” Dr. Crystal says.

The researchers then injected billions of these viral concoctions into “garden variety” laboratory mice (mice that are not genetically engineered). They found a strong immune response was generated against the vaccine, and that these antibodies, when put in test tubes, gobbled up cocaine.

Vaccine for Addicts

They then tested the vaccine’s effect on behavior, and found that mice that received the vaccine before cocaine were much less hyperactive while on the drug than mice that were not vaccinated. The effect was even seen in mice that received large, repetitive doses of cocaine. Proportionally, the cocaine doses reflected amounts that humans might use.

The vaccine needs to be tested in humans, of course, says Dr. Crystal, but he predicts that if it works, it will function best in people who are already addicted to cocaine and who are trying to stop using the drug. “The vaccine may help them kick the habit because if they use cocaine, an immune response will destroy the drug before it reaches the brain’s pleasure center.”

A study published in the scientific journal Addiction shows that the Mexican government’s recent efforts to control the manufacture of methamphetamine have caused a drop in methamphetamine treatment admissions in Mexico and in neighbouring Texas.

In 2005 Mexico began controlling its imports of pseudoephedrine (a precursor chemical used in the manufacture of methamphetamine), and in 2008 it became the first country in North America to ban all imports of pseudoephedrine as well as ephedrine, another important precursor chemical. Researchers estimate that the 2005 import controls caused a 12% drop in voluntary methamphetamine treatment admissions in Mexico, with similar reductions in Texas.

An even larger drop in voluntary admissions occurred following the 2007 closure of a commercial chemical company suspected of illicitly importing more than 60 tons of pseudoephedrine into Mexico. The head of the company fled Mexico but was eventually arrested in the United States. Methamphetamine treatment admissions in Mexico decreased by 56% following the closure of the company, with Texas showing similar results.

Signs of Meth Decline

All decreases in admissions appeared to be specific to methamphetamine, as researchers found no concurrent changes in cocaine, heroin, and alcohol treatment admissions during the same period. The study wound up shortly after the 2008 bans on precursor chemicals came into effect, so researchers weren’t able to examine fully the impact of those bans; however, the researchers noted that treatment admissions in Mexico showed signs of declining in the first few months following the bans.

Says lead researcher James Cunningham, a Fulbright Scholar at The University of Arizona: “These findings constitute the first evidence outside the United States that a country’s precursor chemical controls can have positive public health results both domestically and internationally.”

A new study from Karolinska Institutet presents a new technique that makes drug testing possible through exhaled air for the first time. By examining people who had received emergency care for an amphetamine overdose, the researchers found that in all cases there were traces of amphetamine and metamphetamine in the exhaled breath.

“Traditionally, drugs tests have been carried out using urine and blood samples,” says Professor Olof Beck, who led the study. “In recent years we’ve been trying to find simpler alternatives using saliva, which, unfortunately, has proved difficult. Our results open the way for a new kind of drugs test, which is simple and safe to conduct and that requires no integrity-violating monitoring or medical staff.”

Reliable Drug Tests

Drug abuse is a huge social problem and drugs tests are used widely and comprehensively by the healthcare and social services, the legal system, at workplaces and schools. Reliable drugs tests are important for making correct diagnoses and for keeping tabs on drug users to ensure that they are following prescribed treatment. Alcohol can easily be checked in a breathalyser, and the technology is available for conducting measurements in a way that doesn’t violate a person’s integrity. Measurements of other substances in the exhaled breath are available for diagnosing diseases such as asthma and diabetes.

In this present study, which is published in the latest issue of The Journal of Analytical Toxicology, scientists at Karolinska Institutet have developed a new and unique method for collecting narcotic substances from the exhaled breath. This they did by asking subjects to breathe into a specially designed mask for ten minutes, whereupon the exhaled air was collected and passed through a filter, which trapped the narcotic substances. These filters were then analysed using combined liquid chromatography and tandem mass-spectrometry, techniques that are highly sensitive and reliable.

The researchers took samples from 12 patients who had been admitted into emergency care with toxic symptoms after having taken amphetamines. The samples were taken after the effects of the drug had worn off and with the permission of the regional ethical review board in Stockholm. The ingestion of the drug was confirmed in the patient group through urine and blood samples. In all cases, the researchers were able to ascertain the presence of amphetamine and metamphetamine (a narcotics-classed central-stimulating substance similar to amphetamine) in the exhaled breath as well. The measured excretion rate was between 0.2 and 139 pg/min, which is very low compared to the blood and urine. No amphetamine or metamphetamine were detected in samples from healthy controls.

Drugs In Exhaled Breath

“The results are convincing and very promising,” says Professor Beck. “The study is the first to report the possibility of measuring drugs in the exhaled breath, and represents a unique, unexpected finding. We now have to move on to other drugs that are of interest for this type of breath test, and to develop the sampling and analysis methods. An instrument like a breathalyser for drugs would be the optimal solution for the efficient control of drug use by motorists, for example.”

The study was conducted by researchers at the clinical pharmacology division of the Department of Medicine, Solna and at the Psychiatry Unit at the Department of Clinical Science, Karolinska Institutet, and was financed by Vinnova (the Swedish Governmental Agency for Innovation Systems), the Stockholm County Council and the Swedish Research Council.

As fewer people puff on cigarettes, a new smoking trend may be gaining popularity among North American youth. A study published in the journal Pediatrics has found that almost one-quarter of young adults in Montreal had used waterpipes (also known as shishas or hookahs) in the past year.

“The popularity of waterpipes may be due in part to perceptions that they are safer than cigarettes. However, waterpipe smoke contains nicotine, carbon monoxide, carcinogens and may contain greater amounts of tar and heavy metals than cigarette smoke,” warns senior investigator Jennifer O’Loughlin, a professor at the University of Montreal Department Of Social and Preventive Medicine and a scientist at the University of Montreal Hospital Research Center.

Hookahs Popular Among Males

As part of a longitudinal cohort investigation (NDIT Study), 871 youth aged 18 to 24 completed questionnaires on their smoking habits. The research team, which included scientists from the University of Montreal, the National Institute of Public Health of Quebec and McGill University, found that 23 percent of respondents had used a waterpipe within the last 12 months and that 5 percent had used waterpipes one or more times in the past month.

The study found waterpipes to be particularly popular among young, English-speaking males who lived on their own and had a higher household income. In addition, the research team found that waterpipe users were more likely to use other psychoactive substances such as cigarettes, marijuana, illicit drugs and alcohol.

Young adults who have used cannabis or marijuana for a longer period of time appear more likely to have hallucinations or delusions or to meet criteria for psychosis, according to a report posted online today that will appear in the May print issue of Archives of General Psychiatry, one of the JAMA/Archives journals.

Previous studies have identified an association between cannabis use and psychosis, according to background information in the article. However, concerns remain that this research has not adequately accounted for confounding variables.

Cannabis Use and Psychotic Outcomes

John McGrath, M.D., Ph.D., F.R.A.N.Z.C.P., of the Queensland Brain Institute, University of Queensland, Australia, and colleagues studied 3,801 young adults born between 1981 and 1984. At a 21-year follow-up, when participants were an average age of 20.1, they were asked about cannabis use in recent years and assessed using several measures of psychotic outcomes (including a diagnostic interview, an inventory of delusions and items identifying the presence of hallucinations).

At the 21-year follow-up, 17.7 percent reported using cannabis for three or fewer years, 16.2 percent for four to five years and 14.3 percent for six or more years. Overall, 65 study participants received a diagnosis of “non-affective psychosis,” such as schizophrenia, and 233 had at least one positive item for hallucination on the diagnostic interview.

Among all the participants, a longer duration since the first time they used cannabis was associated with multiple psychosis-related outcomes. “Compared with those who had never used cannabis, young adults who had six or more years since first use of cannabis (i.e., who commenced use when around 15 years or younger) were twice as likely to develop a non-affective psychosis and were four times as likely to have high scores on the Peters et al Delusions Inventory [a measure of delusion],” the authors write. “There was a ‘dose-response’ relationship between the variables of interest: the longer the duration since first cannabis use, the higher the risk of psychosis-related outcomes.”

Not a Simple Connection

In addition, the researchers assessed the association between cannabis use and psychotic symptoms among a subgroup of 228 sibling pairs. The association persisted in this subgroup, “thus reducing the likelihood that the association was due to unmeasured shared genetic and/or environmental influences,” the authors continue.

“The nature of the relationship between psychosis and cannabis use is by no means simple,” they write. Individuals who had experienced hallucinations early in life were more likely to have used cannabis longer and to use it more frequently. “This demonstrates the complexity of the relationship: those individuals who were vulnerable to psychosis (i.e., those who had isolated psychotic symptoms) were more likely to commence cannabis use, which could then subsequently contribute to an increased risk of conversion to a non-affective psychotic disorder.”

The findings should encourage further research to elucidate the mechanisms underlying the relationship between psychosis and cannabis use, the authors conclude.

Exposure to ecstasy or cocaine during adolescence increases the “reinforcing effects” that make people vulnerable to developing an addiction. This is the main conclusion of a research team from the University of Valencia (UV), which has shown for the first time how these changes persist into adulthood.

“Although MDMA and cocaine are psychoactive substances frequently used by teenagers, very few studies have been done to analyse the short and long-term consequences of joint exposure to these drugs”, José Miñarro, lead author of the study and coordinator of the Psychobiology of Drug Addiction group at the UV, tells SINC.

Long Lasting Changes

The study, published in the journal Addiction Biology, shows for the first time that exposure to these drugs during adolescence leads to long-lasting changes that increase the reinforcing power of ecstasy or MDMA, and which last until adulthood.

Miñarro’s team studied the joint consumption of different drugs in order to carry out an in-depth examination into the effects of this interaction. The scientists administered MDMA, cocaine and saline solution to mice over an eight-day period. “The animals exhibited an increase in vulnerability to re-establishing behaviour (relapse), showing a preference for certain environments previously associated with the pleasant effects of the drug”, explains Miñarro.

The results highlight that the so-called “reinforcing effects” are greater in adult mice treated with ecstasy or cocaine during adolescence than in adolescent mice not exposed to these drugs. “Adolescence is a critical stage in development, during which time drug consumption affects plastic cerebral processes in ways that cause changes that persist right through to adulthood”, adds the scientist.

Adolescence Polyconsumption

The results of various surveys, both national and international, show that one of the most common patterns of drug use is polyconsumption. Ecstasy is regularly consumed alongside other drugs such as alcohol, cannabis and cocaine. These same surveys show that 44% of cocaine users in Spain also take ecstasy, and this consumption takes place primarily during adolescence.

The State Study on Drug Use among Secondary School Students (ESTUDES 2007, Government Delegation for the National Plan on Drugs), showed that more than 75% of secondary school students who reported taking MDMA also said they used cocaine, while only 44.3% of cocaine users said they took ecstasy.