Allopregnanolone / Traumatic Brain Injury (TBI) · Phase 2 Trial

Allopregnanolone in Chronic Complex Traumatic Brain Injury

ClinicalTrials.gov · September 8, 2026

Preliminary Why this matters to you Expert discussion

Early or partial results. Treat as a signal, not a conclusion.

AI Summary

This is a Phase 2 trial registration for allopregnanolone in chronic mild traumatic brain injury with primary endpoints of depression and pain symptoms. No results have been posted to the registry and recruitment has not yet begun; this record documents intent to study only.

What was studied

Phase 2, Interventional, Randomized, Parallel, Quadruple masking, Treatment purpose. Traumatic Brain Injury (TBI); age from 21 Years; to 62 Years. Intervention: Placebo; ALLO 50 nanomolar (nM); ALLO 150 nanomolar (nM). Compared with: Placebo intravenous infusion. n = 132. 1 site: United States.

Key findings

Safety

Efficacy, safety, tolerability, and all outcome data are unknown.

Who this may help

The source did not state who this applies to in practice.

Plain-language summary

This is a Phase 2 trial registration with no results posted; the study is not yet recruiting and has not reported efficacy or safety data.

Study design

As stated by the source record.

MethodsPrimary outcome measures: Brief Pain Inventory, Short Form (BPI-SF) Change (assessed at 6 hours, 24 hours, 7 days, and 14 days); Hamilton-Depression Inventory (HAM-D) Change (assessed at 6 hours, 24 hours, 7 days, and 14 days)

DesignPhase 2, Interventional, Randomized, Parallel, Quadruple masking, Treatment purpose

PopulationTraumatic Brain Injury (TBI); age from 21 Years; to 62 Years

Sample size132

InterventionPlacebo; ALLO 50 nanomolar (nM); ALLO 150 nanomolar (nM)

ComparatorPlacebo intravenous infusion

Setting1 site: United States

Reported figures

Quoted from the source exactly as published.

Planned enrollment132

Study phasePhase 2

Primary outcome measure 1Brief Pain Inventory, Short Form (BPI-SF) Change at 6 hours, 24 hours, 7 days, and 14 days

Primary outcome measure 2Hamilton-Depression Inventory (HAM-D) Change at 6 hours, 24 hours, 7 days, and 14 days

Recruitment statusNOT_YET_RECRUITING

Caveats

This is a registry record only; no results have been posted and the study has not yet begun recruitment.
Efficacy, safety, tolerability, and all outcome data are unknown.
No information provided on population characteristics, inclusion/exclusion criteria beyond TBI history, or dosing regimens for allopregnanolone.
Study completion date and data availability timeline are not stated in this record.

Evidence assessment

Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.

Study design

moderate

Phase 2 interventional design with placebo control; design appropriate for early efficacy signals.

Directness

moderate

Clinical outcomes (pain, depression) directly relevant; mild TBI population matches stated condition.

Consistency

insufficient

No results reported; consistency cannot be assessed from registry record alone.

Risk of bias

insufficient

Study not yet recruiting; blinding, allocation concealment, and completeness unknown.

Sample adequacy

limited

Estimated enrollment 132 participants; adequate for Phase 2 but small for definitive efficacy claim.

What is missing. This record has no key findings. That is a gap in the analysis, not a judgement about the study.

Source abstract

Registry record from ClinicalTrials.gov (NCT04003285). This is a study registration, not published results. Lead sponsor: VA Office of Research and Development. Recruitment status: NOT_YET_RECRUITING. Phase: PHASE2. Study type: INTERVENTIONAL. Enrollment: 132 participants (ESTIMATED). Conditions: Traumatic Brain Injury (TBI). Interventions: DRUG: Placebo; DRUG: Allopregnanolone; DRUG: Allopregnanolone. Primary outcome measures: Brief Pain Inventory, Short Form (BPI-SF) Change , 6 hours, 24 hours, 7 days, and 14 days; Hamilton-Depression Inventory (HAM-D) Change , 6 hours, 24 hours, 7 days, and 14 days. Brief summary: This study will determine if allopregnanolone (ALLO) improves depression and pain symptoms in patients who have a history of mild traumatic brain injury (TBI) \[primary endpoints\]. The investigators will also determine if ALLO improves functional outcome \[secondary endpoint\]. Participants in this study will receive an intravenous infusion of either ALLO or placebo. Behavioral assessments will be conducted during the infusion and at several time points post-infusion.

Follow from this

Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.

AllopregnanoloneVA Office of Research and DevelopmentNCT04003285Traumatic Brain Injury (TBI)