A Phase 2 interventional study of 17β-estradiol and Placebo in Chronic Musculoskeletal Pain, Sexual Assault and Posttraumatic Stress Disorder (PTSD), sponsored by University of North Carolina, Chapel Hill. Not yet recruiting. Open to female participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2026-10-09.
Sponsored by University of North Carolina, Chapel Hill · Phase 2, Interventional, and Prevention
This pilot randomized, double-blind, placebo-controlled trial evaluates the feasibility, acceptability, and tolerability of administering a single 6 mg oral dose of 17β-estradiol (E2) to individuals assigned female at birth who have experienced a sexual assault (SA) within the previous 120 hours. Thirty participants aged 18 to 45 years will be randomized 1:1 to receive either E2 or an identical-appearing placebo and followed for three months with blood collection and standardized assessments. The study will evaluate recruitment, enrollment, retention, biological responses, and preliminary clinical outcomes, including chronic musculoskeletal pain (CMSP) and posttraumatic stress disorder (PTSD), to inform the design of a future fully powered efficacy trial.
One in five U.S. females experience sexual assault in their lifetime, and CMSP and PTSD are common, costly, and difficult-to-treat outcomes. Despite the substantial public health burden of these conditions, few therapeutics exist to prevent CMSP or PTSD after SA. Preclinical and observational studies suggest that early administration of 17β-estradiol (E2) following traumatic stress may reduce the risk of developing CMSP and PTSD, with evidence indicating that the timing of E2 exposure relative to the traumatic event is critical. However, no randomized clinical trial has yet evaluated whether early E2 administration can prevent these outcomes following SA.
To address this gap, this pilot, randomized, double-blind, placebo-controlled trial will enroll 30 individuals assigned female at birth, aged 18 to 45 years, who experienced SA within the prior 120 hours. After screening and confirmation of eligibility, participants will be randomized 1:1 to receive either a single oral 6 mg dose of encapsulated E2 (three 2 mg tablets) or an identical placebo within 120 hours of the SA.
Blood samples will be collected immediately before study drug administration and again 90 to 120 minutes afterward to assess circulating E2, cortisol, inflammatory mediators (including IL-6, IL-8, IFN-γ, IL-10, and TNF-α), and RNA expression. Participants will complete standardized assessments of pain, PTSD symptoms, and related clinical outcomes at baseline and at Week 2, Week 6, and Month 3 following enrollment. The Month 3 visit will include a final blood collection.
The primary objectives of this pilot study are to evaluate the feasibility, acceptability, and tolerability of administering early E2 following SA. Secondary and exploratory objectives include characterizing the biological response to E2 administration and obtaining preliminary estimates of its effects on CMSP and PTSD symptoms. Findings from this study will inform the design and implementation of a future fully powered efficacy trial.
The selected E2 dose is based on observational findings demonstrating that peritraumatic circulating E2 concentrations above approximately 100 pg/mL are associated with a lower risk of CMSP and PTSD, together with the established safety profile of comparable oral E2 doses in other clinical settings.
2,284 studies on the registry are indexed under Stress Disorders, Post-Traumatic; 557 are open to participants now.
This study's planned enrollment of 30 is below the median of 70 across 1,897 interventional studies indexed under Stress Disorders, Post-Traumatic.
Browse Stress Disorders, Post-Traumatic studies →University of North Carolina, Chapel Hill is the lead sponsor of 1,366 studies on the registry; 133 are open to participants now.
Of its 158 completed or terminated interventional studies of FDA-regulated products, 139 (88%) have results posted.
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Exclusion Criteria:
Participants receive a single oral 6 mg dose of micronized 17β-estradiol (three encapsulated 2 mg tablets) administered within 120 hours of sexual assault.
Drug: 17β-estradiol
Participants receive a single oral dose of matching placebo administered within 120 hours of sexual assault.
Drug: Placebo
Single oral 6 mg dose micronized 17β-estradiol administered once.
Single oral dose of matching placebo administered once.
Enrollment feasibility
Number and proportion of eligible individuals who complete the Screening Consent and are enrolled in the study.
Time frame: Throughout the recruitment period, up to 18 months
Participant retention at Month 3
Proportion of enrolled participants who complete the Month 3 in-person visit, including final blood collection and study questionnaires. The prespecified retention target is at least 80%.
Time frame: 3 months after study-drug administration
Acceptability of the study intervention
Participant-reported acceptability of the study intervention, assessed using items from the Medication Acceptability Questionnaire, including overall acceptability and willingness to recommend the intervention to others.
Time frame: Enrollment Visit, following study drug administration, through Month 3
Tolerability of the study intervention
Number and proportion of participants reporting side effects or adverse events following study drug administration.
Time frame: Study drug administration through Month 3
Plasma 17β-estradiol concentration
Change in plasma 17β-estradiol concentration from pre-dose to 90-120 minutes after study-drug administration, compared between treatment groups.
Time frame: Pre-dose and 90-120 minutes post-dose
Plasma cortisol concentration
Change in plasma cortisol concentration from pre-dose to 90-120 minutes after study-drug administration and differences between treatment groups at Month 3.
Time frame: Pre-dose, 90 to 120 minutes post-dose, and Month 3
Plasma inflammatory mediator concentrations
Changes in plasma concentrations of IL-6, IL-8, IFN-γ, IL-10 and TNF-α from pre-dose to 90-120 minutes after study-drug administration and differences between treatment groups at Month 3.
Time frame: Pre-dose, 90 to 120 minutes post-dose, and Month 3
RNA expression
Changes in peripheral-blood RNA expression following study-drug administration, including differences in RNA expression profiles between treatment groups 90-120 minutes after study-drug administration and longitudinal changes from enrollment to Month-3.
Time frame: Pre-dose, 90 to 120 minutes post-dose, and Month 3
Musculoskeletal pain severity
Pain severity measured using a 0 to 10 numeric rating scale, with higher scores indicating greater pain severity. Scores and changes from baseline will be compared between treatment groups.
Time frame: Baseline, Week 2, Week 6, and Month 3
Posttraumatic stress disorder symptom severity (PCL-5)
Posttraumatic stress symptoms measured using the 20-item PTSD Checklist for DSM-5 (PCL-5). Total scores range from 0-80, with higher scores indicating greater symptom severity. Scores and changes from baseline will be compared between treatment groups.
Time frame: Baseline, Week 2, Week 6, and Month 3
No study locations are listed for this record.
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — De-identified individual participant data (IPD) underlying the results reported in published manuscripts may be shared after publication of the primary study findings. All shared data will be de-identified in accordance with applicable federal regulations and institutional policies.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: Within approximately 6 months of publication of the primary study results.
Access criteria: Requests for data access will be reviewed by the study investigators on a case-by-case basis. Qualified researchers with a methodologically sound proposal may be granted access following approval by the study investigators and, as applicable, the Institutional Review Board (IRB). Data will be shared through secure methods and may require execution of a data use agreement in accordance with institutional policies.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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