NCT06261905

Vitamin D in OUD: Exploration of Alterations on the Dopamine D2/D3 Receptor System

Exploration of Baseline Alterations on the Dopamine D2/D3 Receptor System and the Effects of Vitamin D in Opioid Use Disorder: an [11C]-PHNO Study

• Status: Completed
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 5 (actual)
• Sponsor: Yale University · Academic / Other
• Sex: All
• Age: 18 Years – 50 Years
• Healthy volunteers: Accepted

Summary

The research team is investigating Opioid Use Disorder (OUD), a disorder characterized by dysregulated dopaminergic tone, to evaluate the mechanisms of adjunctive treatment with calcitriol. The investigators will recruit 12 subjects with OUD and 12 healthy subjects to participate in a double-blind, randomized study design where subjects will complete up to 2 Positron Emission Tomography (PET) scans using \[11C\]-PHNO. The investigators will compare subjects in differences between their own study days and in differences between healthy control subjects and subjects with OUD.

Detailed description

Previous research has indicated that Dopamine (DA) may play a role in withdrawal and dependence in Opioid Use Disorder (OUD). The present study will investigate dopamine receptor availability in 12 subjects with OUD compared with 12 HC subjects using \[11C\](+)-PHNO and the impact of calcitriol on these receptors. Research has indicated that a common feature in substance use disorders (SUD) is a hypo-dopaminergic state. Further, preclinical and observational research has pointed to a possible benefit of calcitriol in individuals who have OUD and our research group has previously shown the potential benefits of calcitriol on addressing this hypo-dopaminergic state. If successful, the results of this research study may improve the standard treatment for OUD through calcitriol supplementation. Specifically, the present study seeks to address the following aims: Specific Aim 1: As part of a between-subject study design, to determine whether acute calcitriol (vs. placebo) administration is associated with greater dopamine (DA) release in the caudate, putamen, ventral striatum (VST), and substantia nigra / ventral tegmental area (SN/VTA) of subjects with OUD compared to healthy control subjects (HCs). Specific Aim 2: As part of a within-subject, two-day study design, to determine whether acute calcitriol (vs. placebo) administration is associated with greater dopamine (DA) release in the caudate, putamen, ventral striatum (VST), and substantia nigra / ventral tegmental area (SN/VTA) of subjects with OUD. Specific Aim 3: To determine whether acute calcitriol (vs. placebo) administration is associated with higher spontaneous eyeblink rate, a non-PET indicator of higher dopamine activity, among subjects with OUD. Specific Aim 4: To determine whether acute calcitriol (vs. placebo) administration is associated with better performance on neurocognitive measures (e.g., the Continuous Performance Task or CPT-IP and the Probabilistic Reversal Learning Task or PRLT) among subjects with OUD.

Conditions

• Opioid Use Disorder

Interventions

Type	Name	Description
DRUG	[11C]-PHNO	PHNO is used as a tracer for in-vivo imaging.
DIETARY_SUPPLEMENT	Calcitriol	Calcitriol is an active form of Vitamin D and is given in 3 0.5mcg capsules per dose.
OTHER	Placebo Control	A placebo is an inert capsule, which contains no active ingredients. The placebo will be given in 3 0.5mcg capsules per dose.
PROCEDURE	PET Scan	A high resolution PET Scan performed using a NeurExplorer CT scanner.

Timeline

• Start date: 2024-03-13
• Primary completion: 2025-02-18
• Completion: 2025-02-18
• First posted: 2024-02-15
• Last updated: 2025-11-14

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study