This was also the first double-blind clinical trial to include women. Women and men responded equally well to LAAM, and high doses were found to be safe for both male and female heroin addicts.
LAAM was approved by the Food and Drug Administration as an opiate treatment medication in 1993 and was, at that time, the first new drug treatment medication approved in more than two decades. LAAM’s main advantage over methadone, widely used in heroin treatment, is that its effects last long enough so that it need be taken only three times per week. Methadone needs to be taken daily, requiring either a daily trip to a clinic or take-home dosages.
"This study reinforces the fact that heroin addiction can be treated effectively," said Dr. Alan I. Leshner, director of the National Institute on Drug Abuse, National Institutes of Health, which supported this research. "When higher doses of LAAM are used in combination with other drug abuse treatment methods, such as behavioral therapies and psychosocial care, we may see even more positive outcomes for persons who are opioid dependent."
The 17-week study was conducted with 180 heroin-dependent volunteers (70 females, 110 males) by researchers at the Behavioral Pharmacology Research Unit of the Johns Hopkins University Bayview Medical Center in Baltimore, Md. None of the volunteers was concurrently in a treatment program. Upon admission to the study, patients were randomly assigned to a high-, medium-, or low-dose LAAM therapy group.
LAAM reduced heroin use in a dose-related pattern. Before assignment to the high-dose group, patients reported using heroin an average of 29 of the past 30 days. After 16 weeks of LAAM treatment, these same patients reported using heroin an average of 2.5 of the past 30 days, a reduction of nearly 90 percent. Patients assigned to the medium-dose treatment group reported using heroin an average of 4.1 days and those in the low-dose group an average of 6.3 days. These self-report findings were corroborated through urine testing. In addition, patients taking high-doses of LAAM were twice as likely to achieve four weeks of full abstinence compared to patients taking lower doses of LAAM.
Both men and women showed the same general positive relationship between dose level and treatment effectiveness. However, six of the eight women who left treatment reported feeling overmedicated. The researchers suggest that adjusting LAAM doses for weight variation may decrease the overmedication and promote patient retention.
"This study is important because the effectiveness of the most widely used heroin-dependence medication, methadone, has not been fully realized because of a lack of information regarding effective doses," said Dr. George Bigelow, director of the Pharmacology Research Unit at Johns Hopkins
University. "The completion of this dose-comparison study of LAAM will allow clinicians to base their dosing decisions on empirical data and may help to increase LAAM’s therapeutic effectiveness."
This research was funded by the National Institute on Drug Abuse, NIH, whose Medications Development Division has coordinated federal efforts to develop medications to augment behavioral and psychotherapies also used in comprehensive drug treatment programs.
NIDA supports more than 85 percent of the world’s research on the health aspects of drug abuse and addiction and carries out a large variety of programs to disseminate research information. Further information on NIDA’s research and activities can be found on the NIDA Home Page at http://www.nida.nih.gov.