By Jacob Sullum
In October I discussed a study that found a cocaine "vaccine," which is aimed at neutralizing the drug's psychoactivity, was mostly ineffective at getting users to cut back on their consumption. On Tuesday The Washington Post ran a weirdly late story about the same study in which the lead author offers a decidedly more negative spin than he did last fall:
The vaccine, called TA-CD, shows promise but could also be dangerous; some of the addicts participating in a study of the vaccine started doing massive amounts of cocaine in hopes of overcoming its effects, according to Thomas R. Kosten, the lead researcher on the study, which was published in the Archives of General Psychiatry in October.
"After the vaccine, doing cocaine was a very disappointing experience for them," said Kosten, a professor of psychiatry and neuroscience at Baylor College of Medicine in Houston.
Nobody overdosed, but some of them had 10 times more cocaine coursing through their systems than researchers had encountered before, according to Kosten. He said some of the addicts reported to researchers that they had gone broke buying cocaine from multiple drug dealers, hoping to find a variety that would get them high.
The headline over the story misleadingly says, "Testing of Cocaine Vaccine Shows It Does Not Fully Blunt Cravings for the Drug." In fact, as I noted in my original post, the vaccine does not "blunt cravings" at all. It is not designed to do so; instead it is designed to stimulate an immune system response that causes antibodies to bond with cocaine molecules, thereby making them too big to pass the blood-brain barrier. In this study, less than two-fifths of the subjects who received the vaccine had what the researchers considered an adequate immune response, and only half of those subjects reduced their cocaine use by 50 percent or more. Among the subjects with the strongest immune responses, 45 percent of urine samples tested negative for cocaine, compared to 35 percent for the rest of the subjects (weak responders and placebo recipients). Using that measure, you could say the vaccine boosted the success rate by 28 percent, which sounds impressive. But only one out of five subjects who got the vaccine substantially reduced his cocaine use, and some ended up consuming more than they were before the study.
Even if the vaccine worked perfectly, cocaine cravings would be unaffected; they just couldn't be satisfied anymore. Hence this approach probably will appeal only to highly motivated addicts who are committed to quitting. That's assuming its use is voluntary; as I said in October, the prospect of mandatory anti-drug vaccination is not far-fetched given our government's generally coercive approach to illegal drug users. And this study suggests that such forcible treatment, even leaving aside the violation of liberty, could well leave the "patients" worse off, spending more money and consuming more cocaine while enjoying it less.
By Jacob Sullum