Characterizing Drug Liking During Drug Administration in Peri-procedural Clinical Settings

The purpose of this study is to evaluate whether medications used in peri-procedural clinical settings can modulate drug liking.

Study Overview

• Status: Not yet recruiting
• Conditions: Drug Liking
• Intervention / Treatment: Drug: Placebo; Drug: Amisulpride

Detailed Description

Specifically, we aim to measure differences in drug liking with a VAS (0 - 100) questionnaire. Additionally, we will monitor neural activity recording a frontal electroencephalogram (EEG) to detect changes in brain signals associated with opioid drug effects. By comparing behavioral and neurophysiological data across treatment and control groups, this study seeks to explore the therapeutic potential of this medication.

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Early Phase 1

Contacts and Locations

• Study Contact: Name: Patrick L Purdon, PhD; Phone Number: 6507367331; Email: ppurdon@stanford.edu

Study Locations

• United States
  • California
    • Palo Alto, California, United States, 94304
      • Stanford Hospital
      • Contact: Patrick Principal Investigator; Phone Number: 6179706739; Email: ppurdon@stanford.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) physical status classification of I, II or III
• Candidates who are expected to receive fentanyl up to 3 mcg/kg IBW for their scheduled for surgery or procedure

Exclusion Criteria:

• Craniofacial abnormalities
• Known or suspected difficult intubation or mask ventilation
• Known or suspected need for rapid sequence induction and intubation
• Allergies or hypersensitivities to amisulpride or fentanyl
• Clinically significant pulmonary disease, such as chronic obstructive lung disease requiring long-term oxygen therapy, or other conditions that, in the study team's judgment, may increase the risk of severe respiratory depression with opioid administration
• History of long QT syndrome
• Any heart rhythm other than normal sinus rhythm (including but not limited to atrial fibrillation, atrial flutter, paced rhythms, ventricular tachycardia, or any supraventricular tachycardia)
• History of Torsades de Pointes
• History of psychosis
• History of movement disorders e.g. Parkinson's Disease
• Past chronic use of anti-psychotics
• Current use of amisulpride, droperidol, levodopa, lithium, clozapine, metoclopramide, benzodiazepines
• Current use of opioids
• History of opiate abuse within the last 3 years
• Known or suspected severe chronic pain condition that require use of opiates or limit daily activities
• History of pheochromocytoma
• History of concomitant prolactin-dependent tumors e.g. prolactinoma, breast cancer
• Pregnancy or nursing
• Failure to satisfy the investigator of fitness to participate for any other reason

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Participants receive placebo prior to fentanyl administration before their procedure.	Drug: Placebo; Matching Placebo given by single intravenous (IV) administration.
Experimental: Drug; Participants receive study drug prior to fentanyl administration before their procedure.	Drug: Amisulpride; Medication administered as a single intravenous dose.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Drug Liking Rating	Change in drug liking rating (0-100), anchored by divert "not at all=0" and "as much as possible=100".	One minute before and 1, 3, and 5 minutes after fentanyl administration

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Sedation Rating	Change in self-reported sedation rating (0-100), anchored by divert "not at all=0" and "as much as possible=100".	One minute before and 1, 3, and 5 minutes after fentanyl administration
EEG band power	Assessment of the change in power of the frontal EEG canonical frequency bands measured in decibles (dB).	From administration of the study drug to about 1 hour after.

Collaborators and Investigators

• Sponsor: Stanford University

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2026
• Primary Completion (Estimated): March 31, 2027
• Study Completion (Estimated): March 31, 2028

Study Registration Dates

• First Submitted: January 8, 2026
• First Submitted That Met QC Criteria: January 8, 2026
• First Posted (Estimated): January 16, 2026

Study Record Updates

• Last Update Posted (Estimated): January 16, 2026
• Last Update Submitted That Met QC Criteria: January 8, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Organic Chemicals; Hydrocarbons; Hydrocarbons, Cyclic; Carboxylic Acids; Hydrocarbons, Aromatic; Amides; Benzene Derivatives; Acids, Carbocyclic; Benzoates; Benzamides; Amisulpride
• Other Study ID Numbers: IRB-80824

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes