by Kristen Philipkoski
Wired
A researcher who a year ago published startling research showing that the drug commonly known as ecstasy can cause Parkinson's-like brain damage has retracted his study.
George Ricaurte, the Johns Hopkins Medical School researcher who performed the research, said his lab did not administer ecstasy, or MDMA, but methamphetamine, to the primates in the study.
The Sept. 27, 2002 study warned that even one typical recreational dose of MDMA could cause severe brain damage. Scientists around the country applauded the study and warned young people not to experiment with ecstasy. Now Ricaurte says it was a case of mixed up bottles.
"We write to retract our report 'Severe dopaminergic neurotoxicity in primates after a common recreational dose regimen of MDMA (Ecstasy)' following our recent discovery that the drug used to treat all but one animal in that report came from a bottle that contained methamphetamine instead of the intended drug MDMA," Ricaurte said in the retraction, to be published in the Sept. 8 issue of Science.
Ricaurte's lab requested a batch of methamphetamine and a batch of MDMA from a supplier on the same day soon before the study began. The bottles were mislabeled, the retraction says.
The labeling error was discovered after Ricaurte tried repeatedly to duplicate the results he published in the September 2002 study, the retraction said. He could not achieve the same brain damage in the primates in further research, so he became suspicious that something was amiss.
He went back and inspected the bottle that originally accompanied the supposed MDMA and found that it was not methamphetamine but MDMA. The supposed bottle of MDMA was already empty, but some frozen monkey brains left over from the study remained. Inspection of them showed evidence of methamphetamine, but no ecstasy.
Ricaurte and Johns Hopkins pointed out that while this particular study is not valid, other studies showing the potential for different types of brain damage from MDMA use are still sound.
"While it is unfortunate the labeling error occurred, this in no way undermines the results of numerous previous studies performed in multiple laboratories worldwide demonstrating the serotonin neurotoxic potential of recreational doses of MDMA in various animal species, including several primate species," the university said in a statement.
But critics say this is evidence that all of Ricaurte's work should be re-evaluated.
"This (retraction) shows that Ricaurte is completely overzealous in trying to promote the harmful effects of MDMA, and he has ignored evidence to the contrary," said Rick Doblin, president of the Multidisciplinary Association for Psychedelic Studies in Sarasota, Florida.
Previous human studies had already shown that ecstasy did not lead to Parkinson's, he said.
Ricaurte also noted that some recent studies have shown preliminary evidence of Parkinson's-like brain damage as a result of MDMA, but the evidence is not conclusive.
"Until the dopamine neurotoxic potential of MDMA in primates can be examined more fully, this possibility remains uncertain," Ricaurte said in the retraction.
Even before the retraction, groups who believe his method of administration -- injection -- was not an accurate model for studying the typical MDMA dose, which is most commonly taken orally, criticized Ricaurte's research.
Doblin is sponsoring the first FDA-approved clinical trial on the potential therapeutic benefits of MDMA. He said he expects to get final approval for the study in the next two weeks.
Because ecstasy creates feelings of euphoria, warmth and empathy, many therapists believe it could have therapeutic uses for people with post-traumatic stress disorder and other psychological problems.
Wired
A researcher who a year ago published startling research showing that the drug commonly known as ecstasy can cause Parkinson's-like brain damage has retracted his study.
George Ricaurte, the Johns Hopkins Medical School researcher who performed the research, said his lab did not administer ecstasy, or MDMA, but methamphetamine, to the primates in the study.
The Sept. 27, 2002 study warned that even one typical recreational dose of MDMA could cause severe brain damage. Scientists around the country applauded the study and warned young people not to experiment with ecstasy. Now Ricaurte says it was a case of mixed up bottles.
"We write to retract our report 'Severe dopaminergic neurotoxicity in primates after a common recreational dose regimen of MDMA (Ecstasy)' following our recent discovery that the drug used to treat all but one animal in that report came from a bottle that contained methamphetamine instead of the intended drug MDMA," Ricaurte said in the retraction, to be published in the Sept. 8 issue of Science.
Ricaurte's lab requested a batch of methamphetamine and a batch of MDMA from a supplier on the same day soon before the study began. The bottles were mislabeled, the retraction says.
The labeling error was discovered after Ricaurte tried repeatedly to duplicate the results he published in the September 2002 study, the retraction said. He could not achieve the same brain damage in the primates in further research, so he became suspicious that something was amiss.
He went back and inspected the bottle that originally accompanied the supposed MDMA and found that it was not methamphetamine but MDMA. The supposed bottle of MDMA was already empty, but some frozen monkey brains left over from the study remained. Inspection of them showed evidence of methamphetamine, but no ecstasy.
Ricaurte and Johns Hopkins pointed out that while this particular study is not valid, other studies showing the potential for different types of brain damage from MDMA use are still sound.
"While it is unfortunate the labeling error occurred, this in no way undermines the results of numerous previous studies performed in multiple laboratories worldwide demonstrating the serotonin neurotoxic potential of recreational doses of MDMA in various animal species, including several primate species," the university said in a statement.
But critics say this is evidence that all of Ricaurte's work should be re-evaluated.
"This (retraction) shows that Ricaurte is completely overzealous in trying to promote the harmful effects of MDMA, and he has ignored evidence to the contrary," said Rick Doblin, president of the Multidisciplinary Association for Psychedelic Studies in Sarasota, Florida.
Previous human studies had already shown that ecstasy did not lead to Parkinson's, he said.
Ricaurte also noted that some recent studies have shown preliminary evidence of Parkinson's-like brain damage as a result of MDMA, but the evidence is not conclusive.
"Until the dopamine neurotoxic potential of MDMA in primates can be examined more fully, this possibility remains uncertain," Ricaurte said in the retraction.
Even before the retraction, groups who believe his method of administration -- injection -- was not an accurate model for studying the typical MDMA dose, which is most commonly taken orally, criticized Ricaurte's research.
Doblin is sponsoring the first FDA-approved clinical trial on the potential therapeutic benefits of MDMA. He said he expects to get final approval for the study in the next two weeks.
Because ecstasy creates feelings of euphoria, warmth and empathy, many therapists believe it could have therapeutic uses for people with post-traumatic stress disorder and other psychological problems.
