This work may not be copied, distributed, displayed, published, reproduced, transmitted, modified, posted, sold, licensed, or used for commercial purposes. By downloading this file, you are agreeing to the publisher’s Terms & Conditions.


Abecarnil for the Treatment of Generalized Anxiety Disorder: A Placebo-Controlled Comparison of Two Dosage Ranges of Abecarnil and Buspirone

Mark H. Pollack, M.D., John J. Worthington, M.D., Gisele Gus Manfro, M.D., Michael W. Otto, Ph.D., and Bonnie G. Zucker

Published: April 1, 1997

Article Abstract

Background: The development of effective and well-tolerated anxiolytic agents is an area of criticalclinical importance. Abecarnil, a beta carboline, is a partial benzodiazepine-receptor agonist thathas demonstrated promise as an anxiolytic agent. In this study, we examine the efficacy, safety, anddiscontinuation-related effects of abecarnil, buspirone, and placebo in the acute and long-term treatmentof patients who have generalized anxiety disorder. Method: This is a double-blind, placebo-controlledstudy of two dosages of abecarnil and buspirone. In total, 464 patients were randomized. Aftera placebo run-in week, patients entered a 6-week double-blind treatment period, followed by an optional18-week maintenance period for treatment responders. After abrupt discontinuation of the acuteor maintenance treatment, patients entered a 3-week placebo-substitution follow-up period. Treatmentresponse was assessed with the Hamilton Rating Scale for Anxiety and the Clinical Global Impressions(CGI) Scale. Results: Compared with placebo, abecarnil showed significant anxiolytic activityearly in the treatment period, particularly in the high-dosage group, though these differences did notmaintain statistical significance at the end of the trial. Buspirone was associated with a slower onset ofaction and better symptom relief than placebo after 6 weeks of therapy. Withdrawal symptomsemerged in patients who abruptly discontinued abecarnil (particularly at the higher dosage) only inthose receiving a longer duration of treatment. Conclusion: The results of this study need to be understoodin the context of a high placebo-response rate, which hampers the ability to demonstrate significantdrug-placebo differences. This study suggests that abecarnil may be an effective anxiolytic agent;further attention is warranted to assess its spectrum of clinical effectiveness.

Some JCP and PCC articles are available in PDF format only. Please click the PDF link at the top of this page to access the full text.

Volume: 58

Quick Links: