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NCT03598140 · ClinicalTrials.gov registry record · Phase 2

Sildenafil Treatment for Mild TBI

A Phase 2 study, sponsored by University of Texas Southwestern Medical Center.

Terminated
Registry status
Phase 2
Development phase
22
Enrollment target

NCT03598140: Clinical Trial Phase 2 study, sponsored by University of Texas Southwestern Medical Center.

NCT03598140 is a Phase 2 study that was terminated before completion, run by University of Texas Southwestern Medical Center. The registered enrollment target is 22 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (83% lower). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT03598140, a Phase 2 study, was terminated before completion, sponsored by University of Texas Southwestern Medical Center.

TERMINATED
Registry status
Phase 2
Development phase
22 participants
Enrollment target

Study Summary

About 300,000 people are hospitalized for traumatic brain injury (TBI) each year. After TBI, secondary brain injury escalates due in part to heightened levels of oxidant injury, inflammation, and vascular injury. Traumatic cerebral vascular injury (TCVI) may begin almost immediately after the primary injury and evolve into chronic neurodegenerative conditions. TCVI is a very complex TBI endophenotype and microvascular injuries have been described in a plethora of animal and human TBI studies. These injuries consist of endothelial injury, disruption of the blood brain barrier (BBB), a reduction of capillary density, intravascular microthrombi, and white-matter degeneration. Recently, use of magnetic resonance imaging (MRI)-Blood Oxygen Level Dependent (BOLD) combined with hypercapnia (high spatial and temporal resolution) by our research group has proven to be more sensitive at measuring alterations of cerebral blood flow (CBF) in TBI subjects. The goal of the proposed research is to test the efficacy of Viagra® (sildenafil) at normalizing CBF and improving cognitive outcomes in people that have experienced a TBI. Sildenafil is a phosphodiesterase-5 (PDE-5) inhibitor that has previously been administered as a therapy for high blood pressure and erectile dysfunction. In people that have been affected by stroke-induce neurotrauma, sildenafil improved CBF and was found to be neuroprotective. With respect to chronic TBI, previous studies have demonstrated that sildenafil therapy potentiates cardiovascular reactivity (CVR) in areas of the brain with damaged endothelium. In this proposal, the investigators will test the hypothesis that sildenafil treatment in boxers/Mixed Martial Arts (MMA) fighters soon after concussion normalizes CBF, potentiates CVR, reduces post-concussion symptoms, and improves cognition.

Primary Outcome

Prior to and after sildenafil treatment (60mg) cerebral blood flow will be measured in the athletes and healthy controls.

Interventions

  • DRUG Placebo oral capsule
  • DRUG Sildenafil Citrate

Trial Details

FieldValue
Enrollment Target 22 participants
Start Date 2018-07-25
Est. Completion 2019-05-29
Phase Phase 2

Why NCT03598140 stopped before completion

NCT03598140 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 22 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (83% lower).

The record links to 0 conditions, and to 2 interventions - of which Placebo oral capsule is the first listed.

NCT03598140 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT03598140 about?

NCT03598140 is a clinical study titled "Sildenafil Treatment for Mild TBI". About 300,000 people are hospitalized for traumatic brain injury (TBI) each year. After TBI, secondary brain injury escalates due in part to heightened levels of oxidant injury, inflammation, and vascular injury. Traumatic cerebral vascular injury (TCVI) may begin almost immediately after the primar...

What is the current status of trial NCT03598140?

This trial is currently terminated. It is a Phase 2 study. The enrollment target is 22 participants. The study started on 2018-07-25. Estimated completion is 2019-05-29.

What interventions are being tested in trial NCT03598140?

The interventions under investigation include: Placebo oral capsule (DRUG), Sildenafil Citrate (DRUG).

Who is sponsoring clinical trial NCT03598140?

This trial is sponsored by University of Texas Southwestern Medical Center, which has 837 total clinical trials registered on ClinicalTrials.gov.

How this trial's enrollment target compares

Where NCT03598140's enrollment target sits among peer trials

22 1790th of 2000 higher than 207 of 2,000 other Phase 2 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT03598140, the US trial registry maintained by the National Library of Medicine. NCT03598140 (small enrollment · none site footprint · terminated) retrieved and formatted by PlainTrial, see methodology.