Clinical Trials

Numerous clinical trials evaluate the therapeutic potential of prazosin from Early Phase 1 through Phase 4 for conditions including post-traumatic stress disorder (PTSD), acute stress disorder, alcohol and drug dependency, nicotine addiction, COVID-19, and Alzheimer's disease. Sponsored by academic institutions such as Johns Hopkins University and Yale University, government organizations like the US Department of Veterans Affairs, and pharmaceutical companies including Otsuka Pharmaceutical, these studies encompass completed, recruiting, terminated, and withdrawn recruitment statuses.

NCT Number Recruitment Conditions Sponsor/Collaborators Start Date Phases
NCT06629090 RECRUITING
Magnetic Resonance Imaging; Cerebrovascular Circulation
University of Wisconsin, Madison
2025-12-17 PHASE2
NCT06629077 RECRUITING
Magnetic Resonance Imaging; Cerebrovascular Circulation
University of Wisconsin, Madison
2026-02-26 PHASE2
NCT04793685 RECRUITING
Alcohol Withdrawal
Yale University
2021-07-01 PHASE2
NCT07231978 COMPLETED
Healthy
Pfizer
2025-11-14 PHASE1
NCT03539614 ACTIVE_NOT_RECRUITING
Posttraumatic Stress Disorder
VA Office of Research and Development
2018-06-04 PHASE3
NCT04721353 COMPLETED
Cannabis Dependence; Posttraumatic Stress Disorder; Cannabis Use Disorder
VA Puget Sound Health Care System
2020-11-09 PHASE4
NCT06147622 COMPLETED
Alcohol Use Disorder
Kinnov Therapeutics
2024-04-23 PHASE1
NCT06287905 UNKNOWN
Morality
Sohag University
2023-02-01 PHASE4
NCT03894345 SUSPENDED
Anxiety; Anxiety Disorders
University of Manitoba
2019-05-24 PHASE1
NCT05189977 TERMINATED
Post-traumatic Stress Disorder (PTSD)
Otsuka Pharmaceutical Development & Commercialization, Inc.
2022-09-07 PHASE1
NCT02266329 COMPLETED
Posttraumatic Headache; Combat Disorders; Post Concussion Syndrome; Headache; Mild Traumatic Brain Injury; Posttraumatic Migraine
VA Office of Research and Development
2016-01-04 PHASE1; PHASE2
NCT02965027 COMPLETED
Post-Traumatic Headache
Seattle Institute for Biomedical and Clinical Research
2016-11-29 PHASE4
NCT03221751 TERMINATED
Dementia
VA Office of Research and Development
2016-12-01 PHASE4
NCT05189977 Terminated
Post-traumatic Stress Disorder (PTSD)
Otsuka Pharmaceutical Development & Commercialization Inc.|Iqvia Pty Ltd
2022-09-07 Phase 1
NCT04365257 TERMINATED
COVID-19
Johns Hopkins University
2020-05-13 PHASE2
NCT04967443 COMPLETED
Hypertension; Heart Failure
Pfizer
2021-09-22 PHASE1
NCT03710642 COMPLETED
Alzheimer's Disease; Disruptive Behavior
Alzheimer's Disease Cooperative Study (ADCS)
2018-10-23 PHASE2
NCT04108104 COMPLETED
Alcohol Use Disorder
Kinnov Therapeutics
2019-11-30 PHASE2
NCT03997864 WITHDRAWN
Posttraumatic Stress Disorder
University of Colorado, Denver
2020-02-23 PHASE4
NCT04365257 Terminated
COVID-19
Johns Hopkins University|Fast Grants
2020-05-13 Phase 2
NCT03045016 COMPLETED
Acute Stress Disorder
Hospices Civils de Lyon
2017-04-21 PHASE2
NCT02655354 COMPLETED
Posttraumatic Stress Disorder; Depression; Alcohol-Related Disorders; Suicidal Ideation; Substance-Related Disorders; Mild Cognitive Impairment; Quality of Life; Pain; Wounds and Injury; Brain Injuries; Chronic Disease
University of Washington
2015-10
NCT02431936 COMPLETED
Hypertension; Stress, Psychological; Blood Pressure
Augusta University
2015-04 PHASE2
NCT03416569 WITHDRAWN
no Condition, Basic Science
University of Maryland, Baltimore
2018-03
NCT02322047 COMPLETED
Alcohol Use Disorder; Posttraumatic Stress Disorder (PTSD)
Seattle Institute for Biomedical and Clinical Research
2015-03-03 PHASE2
NCT02226367 COMPLETED
Alcohol Use Disorders; Stress Disorders, Posttraumatic; Combat Disorders
Seattle Institute for Biomedical and Clinical Research
2015-01
NCT00585780 COMPLETED
Alcohol Dependence
Yale University
2009-09 PHASE1; PHASE2
NCT03010995 WITHDRAWN
Cigarette Smoking Toxicity; Nicotine; Acute Cardiovascular Disease
University of Louisville
2018-03-13 PHASE1
NCT02966340 COMPLETED
Alcoholism
University of Wisconsin, Madison
2016-11-01 PHASE1; PHASE2
NCT02382848 COMPLETED
Stress Disorders, Post-Traumatic; Bulimia Nervosa
Milton S. Hershey Medical Center
2015-07
NCT01923129 COMPLETED
Urinary Retention
Cedars-Sinai Medical Center
2012-11-30
NCT02199652 COMPLETED
Post Traumatic Stress Disorder; Suicidal Ideation; Nightmares
Augusta University
2014-03 PHASE4
NCT02384369 WITHDRAWN
Post-Traumatic Stress Disorders; Posttraumatic Stress Disorders; Stress Disorders, Post-Traumatic; Post-Traumatic Stress Disorders, Combat-related
Synchroneuron Inc.
2016-06 PHASE2
NCT03045016 Completed
Acute Stress Disorder
Hospices Civils de Lyon
2017-04-21 Phase 2
NCT00223717 COMPLETED
Hypertension
Vanderbilt University
2001-01 PHASE1
NCT01999530 COMPLETED
Healthy
Centre for Addiction and Mental Health
2013-11 PHASE1
NCT01916941 COMPLETED
Alcohol Use Disorder
University of New Mexico
2013-09
NCT02193256 COMPLETED
Cigarette Smoking; Alcohol Use Disorders
Yale University
2014-07 EARLY_PHASE1
NCT00744055 COMPLETED
Alcohol Dependence; Stress Disorders, Post-Traumatic
Yale University
2009-01 PHASE3
NCT02193256 Completed
Cigarette Smoking|Alcohol Use Disorders
Yale University|National Institute on Alcohol Abuse and Alcoholism (NIAAA)
2014-07 Early Phase 1
NCT00762710 COMPLETED
Alcoholism
Seattle Institute for Biomedical and Clinical Research
2008-01 PHASE2
NCT01126099 COMPLETED
Alzheimer's Disease
Seattle Institute for Biomedical and Clinical Research
2010-03
NCT01642433 TERMINATED
Nicotine Dependence
Centre for Addiction and Mental Health
2012-07 PHASE2
NCT01178138 COMPLETED
Continuous Methamphetamine Abuse
University of Arkansas
2009-12 PHASE2
NCT00990106 COMPLETED
Stress Disorders, Post-Traumatic; Combat Disorders; Sleep Disorders
Seattle Institute for Biomedical and Clinical Research
2009-09
NCT00532493 COMPLETED
PTSD; Sleep Disorders
VA Office of Research and Development
2010-01-06 PHASE3
NCT01637584 COMPLETED
Non PTSD; PTSD
University of Pittsburgh
2010-04
NCT01518972 COMPLETED
Alcohol Abuse; Posttraumatic Stress Disorder
Seattle Institute for Biomedical and Clinical Research
2009-09 PHASE2
NCT00175682 COMPLETED
Autonomic Dysreflexia
University of British Columbia
2004-12
NCT00890643 WITHDRAWN
Posttraumatic Stress Disorder
US Department of Veterans Affairs
2009-12
NCT00713739 UNKNOWN
Kidney Stones
United States Naval Medical Center, San Diego
2008-01 PHASE3
NCT00393874 COMPLETED
Anxiety Disorders; Mood Disorders; Insomnia; Nightmares
University of Pittsburgh
2006-10
NCT01178138 Completed
Continuous Methamphetamine Abuse
University of Arkansas|National Institute on Drug Abuse (NIDA)
2009-12 Phase 2
NCT01621165 WITHDRAWN
Bipolar, Mania; Bipolar, Mixed State
Mclean Hospital
2009-03
NCT00161473 COMPLETED
Alzheimer Disease; Psychomotor Agitation
University of Washington
2001-01
NCT00487032 COMPLETED
Allergic Rhinitis; Tachyphylaxis; Rhinitis Medicamentosa
Brian J Lipworth
2008-05 PHASE4
NCT00183430 TERMINATED
Post-Traumatic Stress Disorder; Sleep Initiation and Maintenance Disorders
Seattle Institute for Biomedical and Clinical Research
2003-10
NCT00240227 TERMINATED
Alcoholism; Cocaine Dependence
US Department of Veterans Affairs
2004-04
NCT00148837 COMPLETED
Hepatitis C, Chronic; Fibrosis
French National Agency for Research on AIDS and Viral Hepatitis
2004-09 PHASE2
NCT00202449 TERMINATED
Stress Disorders, Post-Traumatic; Sleep Disorders
Seattle Institute for Biomedical and Clinical Research
2004-07
NCT00753064 COMPLETED
Scorpion Envenomation
Haffkine Bio-Pharmaceutical Corporation Ltd.
2006-09 PHASE3
NCT00167687 COMPLETED
Alcoholism
University of Washington
2005-09 PHASE4
NCT00261729 COMPLETED
Sleep Disorders; Stress Disorders, Post-Traumatic
US Department of Veterans Affairs
2004-07
NCT00602186 UNKNOWN
Neurogenic Bladder
Tabriz University
2005-07 PHASE1; PHASE2
NCT00108420 COMPLETED
Stress Disorder, Post-Traumatic
US Department of Veterans Affairs
2003-10 PHASE4
NCT00450164 COMPLETED
Gastrointestinal Hemorrhage; Portal Hypertension; Cirrhosis
Fundació Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau
2000-11 PHASE4
NCT00174551 UNKNOWN
Stress Disorders, Post-Traumatic
Rainier Associates
2003-11
NCT00563602 UNKNOWN
Portal Hypertension; Complications of Cirrhosis
Fundació Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau
2007-08 PHASE4

(data from https://clinicaltrials.gov, updated on 2026-07-06)

Check the Prazosin product page for in-depth specifications, including solubility, stock solutions, MOA, and working concentrations.

Compliance for Clinical Use

Mechanism and Biochemical Profile

Prazosin acts as a selective inverse agonist at alpha-1 adrenergic receptors, binding the receptor to suppress G-protein-mediated downstream signaling cascades and block intracellular calcium mobilization. This inhibition relaxes vascular smooth muscle to cause vasodilation while blunting central hyperadrenergic activity, providing therapeutic efficacy in hypertension and addressing clinical trial endpoints related to post-traumatic stress disorder and substance use disorders.

Appendix RUO and cGMP Quality Standards

Quality Dimension RUO (Research Use Only) cGMP (Current Good Manufacturing Practice)
Clinical Applicability Prohibited in human clinical trials or medical diagnostics. Mandatory for human clinical trials (Phase I–III) and therapies.
Regulatory Status Non-regulated grade; exempt from drug manufacturing laws. Legally enforced by health authorities (e.g., FDA, EMA, NMPA).
Facility Environment Unclassified analytical or research laboratories. Validated Cleanrooms (ISO Class 5–8) with continuous monitoring.
Quality Control Basic purity and activity testing. Rigorous safety release testing (Sterility, Endotoxin, Mycoplasma).
Process Validation Basic equipment calibration; no process validation required. Full qualification (IQ/OQ/PQ) and complete batch records.
Quality Assurance Vendor self-declared without required formal QMS. Mandatory QA/QC unit, Change Control, CAPA, and vendor audits.
Regulatory Impact High risk of IND rejection if used as a critical raw material. Required for IND/NDA filings, supported by Drug Master Files (DMF).

Footnotes

Regulatory Note: Governed by FDA (21 CFR Parts 210/211/312), EMA (EudraLex Vol 4), ICH Guidelines (E6/Q7/Q9/Q10), and compendial standards (USP <71>/<85>/<1043>).

Note: Technical data last updated: Sep 1, 2026.