Skip to main content

National Institute on Alcohol Abuse and Alcoholism (NIAAA)

NIAAA Protocol NCIG 006: A Randomized, Double Blind, Placebo-Controlled Trial of the Safety and Efficacy of HORIZANT® (Gabapentin Enacarbil) Extended-Release Tablets for the Treatment of Alcohol Use Disorder


This large, multisite clinical trial evaluated the efficacy and safety of gabapentin enacarbil extended-release (GE-XR) (HORIZANT®), a gabapentin prodrug formulation for the treatment of alcohol use disorder (AUD). 

Study Details

Sponsor: The National Institute on Alcohol Abuse and Alcoholism’s Clinical Investigations Group (NCIG)

NCT #: 02252536

Phase:  Phase 2

Treatment Arms:  Horizant® (gabapentin enacarbil) 600mg twice a day and matching placebo

Number of Clinical Sites: 10 

Number of Participants: 346

Duration: 6 months; efficacy last 4 weeks

Population: Minimum of mild AUD; 34% women; 31% ethnic minorities

Other Study Details: Double-blind, Take Control (computerized behavioral intervention)

Top-line Results: The Horizant® and placebo groups did not differ significantly on the primary outcome measure, percentage of subjects with no heavy drinking days (28.3 vs. 21.5, respectively, p = 0.157) or on any secondary measures of drinking, craving, alcohol-related consequences, mood, sleep, or smoking. Common side-effects were fatigue, dizziness, and somnolence.

The data set was prepared by NIAAA and FastTrack Drugs and Biologics, (the Coordinating Center) and was reviewed by CSR Incorporated. 


Falk DE, Ryan ML, Fertig JB, Devine EG, Cruz R, Brown ES, Burns H, Salloum IM, Newport DJ, Mendelson J, Galloway G, Kampman K, Brooks C, Green AI, Brunette MF, Rosenthal RN, Dunn KE, Strain EC, Ray L, Shoptaw S, Ait-Daoud Tiouririne N, Gunderson EW, Ransom J, Scott C, Leggio L, Caras S, Mason BJ, Litten RZ; National Institute on Alcohol Abuse and Alcoholism Clinical Investigations Group (NCIG) Study Group. 2019. Gabapentin enacarbil extended-release for alcohol use disorder: a randomized, double-blind, placebo-controlled, multisite trial assessing efficacy and safety. Alcohol Clin Exp Res, 43(1):158-169. PMID: 30403402 

Dataset Application Procedure: 

HORIZANT® (Gabapentin Enacarbil) Extended-Release Study contains individual level data and is categorized as a controlled access data set. Only qualified research investigators who, along with their institutions, have certified their agreement with the expectations and terms of access detailed in the Gabapentin Enacarbil Data Access Application and the NIAAA Data Use Agreement will be provided access. 
To apply for access, please send the following to 

1.    A completed NCIG 006 - Gabapentin Enacarbil Data Access Application 
2.    A completed NIAAA Data Use Agreement, signed by your Authorized Institutional Official and the Principal Investigator 

NCIG 006 data use agreement                NCIG 006 data access application


Looking for U.S. government information and services?