NCT01437046

Doxazosin an a1 Antagonist for Alcohol Dependence

• Status: Completed
• Phase: EARLY_Phase 1
• Study type: Interventional
• Enrollment: 41 (actual)
• Sponsor: Brown University · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Not accepted

Summary

Norepinephrine system represents an important treatment target for alcohol dependence (AD) and the α1 -blocker prazosin may reduce alcohol drinking in rodents and alcoholic patients. The α1 -blocker doxazosin demonstrates a more favorable pharmacokinetic profile than prazosin, but has never been studied for AD. A double-blind placebo-controlled randomized clinical trial was designed in AD individuals seeking outpatient treatment. Doxazosin or matched placebo was titrated to 16 mg/day (or maximum tolerable dose). Drinks per week (DPW) and heavy drinking days (HDD) per week were the primary outcomes. Family history density of alcoholism (FHDA), severity of AD and gender were a priori moderators.

Detailed description

Pre-clinical and clinical evidence has clearly demonstrated that the noradrenergic (NE) system is involved in the neurobiology of AD, thus representing an interesting new pharmacotherapy target and the theoretical rationale for this proposal. Consistent with the concept that the NE system may represent a new pharmacological target for AD, recent studies have shown that the prototype alpha-1 NE receptor antagonist prazosin reduces alcohol drinking in different animal models. Furthermore, clinical evidence has also confirmed that prazosin appears to be efficacious in reducing alcohol consumption in alcohol-dependent individuals. While prazosin has a significant side effect profile and must be taken three times a day, no other α1-blockers have been investigated in alcohol research. Prazosin is a short-acting α1-blocker approved to treat hypertension (HTN) and benign prostatic hyperplasia (BPH). After the approval of prazosin in the 70's, other selective α1-blockers have been developed to treat HTN and/or BPH. Among them, doxazosin has shown a more manageable and safer profile than prazosin. In fact, doxazosin is a long-acting α1-blocker, thus it is taken only once/day. Doxazosin is also less likely to give hypotensive side-effects. Thus, doxazosin is more commonly used in clinical practice to treat HTN and/or BPH, than short-acting α1-blockers, such as prazosin. Poor adherence to medications and/or side-effects represent important factors limiting the effectiveness of pharmacotherapies for patients with AD. If effective for AD, doxazosin may represent a simple, manageable and safe medication, which might be more easily transferable to clinical practice. However, doxazosin has never been tested in AD. This project is a 10-week, double-blind, placebo-controlled, between-subject randomized clinical trial with doxazosin (16mg once/day) in alcohol dependent (AD) individuals. This study attempts to address whether doxazosin is an effective and safe pharmacotherapy for AD.

Conditions

• Alcohol Dependence
• Anxiety

Interventions

Type	Name	Description
DRUG	Doxazosin	Doxazosin were prepared as opaque capsules by a compounding pharmacy and inserted into blister packs. Consistent with the recommended titration, doxazosin was titrated up to 16 mg daily (or maximum tolerable dose) during the first 4 weeks. A 1-week downward titration for safety reasons was also planned. Study medication adherence was assessed by self-report and pill count. Additionally, capsules contained 25mg riboflavin as a marker of adherence through urine sample.
DRUG	Placebo	Matched placebo were prepared as opaque capsules by a compounding pharmacy and inserted into blister packs. Consistent with the recommended titration, doxazosin or matched placebo was titrated up to 16 mg daily (or maximum tolerable dose) during the first 4 weeks. A 1-week downward titration for safety reasons was also planned. Study medication adherence was assessed by self-report and pill count. Additionally, capsules contained 25mg riboflavin as a marker of adherence through urine sample.

Timeline

• Start date: 2011-11-01
• Primary completion: 2013-08-01
• Completion: 2015-03-01
• First posted: 2011-09-20
• Last updated: 2025-08-18

Locations

2 sites across 1 country: United States