by David A. Gorelick, MD, PhD
[Winter 1998; Vol.25 No. 3]
The Intramural Research Program (IRP; formerly known as the Addiction Research Center) of the National Institute on Drug Abuse (NIDA) is the world's foremost facility devoted to research on drug abuse. The NIDA IRP conducts research on the etiology, prevention, diagnosis, and treatment of drug abuse and its consequences; and offers research training at the pre- and post-doctoral levels. It is located on the Johns Hopkins Bayview campus in Baltimore, Maryland, has a total annual budget of more than $28 million, and employs more than 300 scientists, trainees, and other staff. The breadth of research conducted is indicated by the 7 scientific laboratories or branches into which the IRP is divided: Molecular Neurobiology, Cellular Neurobiology, Behavioral Neuroscience, Preclinical Pharmacology, Clinical Pharmacology, Neuroimaging, and Treatment. Many research projects involve collaborations among branches and with extramural colleagues, particularly with colleagues at the nearby medical schools of Johns Hopkins University and the University of Maryland at Baltimore.
Clinical research at the IRP uses its 15-bed research ward, 80-slot outpatient clinic (Archway Clinic), Brain Imaging Center (with PET scanner and cyclotron for generating radiolabelled tracers), and its facilities for measurement of EEG, evoked potentials, and cerebral blood flow, 24-hour ambulatory physiological monitoring, and computer-administered psychological and neuropsychological testing. Research is conducted by staff representing a variety of medical specialties and scientific disciplines, including psychiatry (addiction and child), neurology, endocrinology, nuclear medicine, pediatrics, psychology, pharmacology, and neurophysiology. Topics under study in the clinical research program include the genetics of drug abuse, identification of brain circuits and neurotransmitter systems involved with drug craving and use, the roles of drug craving, withdrawal, and pharmacokinetics in drug abuse and relapse, new psychosocial and pharmacological treatments, identification of predictors of treatment response and relapse, and identification and treatment of consequences of drug abuse, including HIV transmission.
A current focus of treatment research is improving care for patients addicted to cocaine, opiates or their combination through behavior therapy or cognitive-behavioral counseling. Contingency management is a form of behavior therapy that rewards abstinence by allowing outpatients to earn a voucher for each clinic visit at which they provide a drug-free urine sample. (All urine samples are collected under direct staff observation via a one-way mirror to minimize the possibility of invalid samples.) Vouchers have a monetary value and can be redeemed for purchase of goods (e.g., television, car) or services (e.g., rent deposit, insurance) that promote recovery, after discussion with the patient's drug abuse counselor. Patients receiving contingency management are significantly more successful in reducing or stopping drug use than those who receive equivalent vouchers on a non-contingent basis, i.e., just for coming to the clinic. Unfortunately, the benefits of contingency management tend to wear off once the contingency is stopped. Studies now underway are evaluating various voucher reinforcement schedules and concomitant counseling techniques to improve the treatment response. Cognitive-behavioral counseling, an adaptation of the psychotherapy approach pioneered by Aaron Beck, has shown promise in reducing HIV transmission risk behaviors, as well as drug use itself. Predictors of treatment response being evaluated include drug craving, socioeconomic status, social support network, and psychiatric comorbidity (assessed with standardized instruments such as the Addiction Severity Index and Diagnostic Interview Schedule). Future studies will evaluate potential biological predictors of treatment response and relapse, such as neurotransmitter binding in the brain (assessed by PET scanning), severity of drug withdrawal, and drug metabolism.
Clinical research volunteers are recruited and screened by a central Recruiting Unit, and receive a thorough medical and psychological evaluation to determine their eligibility for safe participation in research protocols. All clinical services are provided free of charge, including the screening tests, counseling, study medication (if any), and treatment for any research-related conditions. After completion of a clinical trial (typically 8-12 weeks), subjects are referred back to the community for further treatment. Anyone wishing to refer patients for participation in treatment protocols, or individuals interested in participating in any research study, can contact the NIDA IRP Recruiting Unit at (410) 550-1502. Physicians interested in a research fellowship can contact the NIDA IRP Personnel Office at (410) 550-1638.
Dr. Gorelick is Chief, Pharmacotherapy Section, Treatment Branch, NIDA IRP; and Adjunct Professor of Psychiatry, University of Maryland School of Medicine.