Clarification

The article “Buprenorphine Depot Formulation Relieves Withdrawal Symptoms” in the April 16 issue reporting on a study of the use of buprenorphine in the treatment of dependence on both cocaine and heroin contained information that the principal authors of the study believe could mislead readers.

That article reported on the results of two research studies, the first of which used an investigational depot formulation, and the second of which used oral buprenorphine in patients with dual addiction. The headline captured the focus of the first study, but not the second.

The story reported that the second study, “Randomized Trial of Buprenorphine for Treatment of Concurrent Opiate and Cocaine Dependence,” by Ivan Montoya, M.D., M.P.H., and David Gorelick, M.D., Ph.D., both of the National Institute on Drug Abuse (NIDA), and their colleagues investigated four dosing regimens of buprenorphine or placebo for 13 weeks. The study actually compared the four dosing regimens for a 10-week trial of stable dosing, followed by a three-week taper, for a total study period of 13 weeks. There was no placebo arm in the study; placebo was used in one of the four dosing regimens studied, alternating with 16 mg of buprenorphine every other day.

The story correctly reported the results of the study as group means—echoing a NIDA press release on the study—implying that the results correlated to decreases in the number of individuals using drugs and the amount of drug used.

The results reported pertained to the percentages of all urine samples in the group that were positive for drug and to urine drug concentrations across all subjects, respectively. Although both percentages declined, as group means, no inference about the status of drug use by individual subjects within a given group can be drawn. Actual amount of drug used by individuals or the group as a whole was not directly measured.

In addition, the story reported that “those taking 16 mg every other day improved slightly, but generally less than those receiving 8 mg every day.” This conclusion was drawn from graphs of the data presented in the article. However, the authors emphasized, as we noted, that this outcome was not statistically significant.▪