Radiocaine Safety Study

[18F]Radiocaine: Radiation and Radiochemical Safety

This is a Phase 1, single-center, open-label study evaluating the safety, biodistribution, and radiation dosimetry of Radiocaine™, an investigational fluorine-18-labeled PET radiotracer designed to bind voltage-gated sodium channels. The study enrolls adult volunteers and aims to inform future clinical development in molecular imaging applications. Radiocaine™ is being developed as a potential diagnostic imaging agent and imaging biomarker for the localization and quantification of sodium channel activity.

Study Overview

• Status: Recruiting
• Conditions: Healthy Subjects
• Intervention / Treatment: Diagnostic test: Intravenous Radiocaine

Detailed Description

This is a Phase 1, single-center, open-label study evaluating the safety, biodistribution, and radiation dosimetry of Radiocaine™, an investigational fluorine-18-labeled PET radiotracer designed to bind voltage-gated sodium channels.

The study will enroll six healthy adult volunteers, each of whom will receive a single intravenous dose of Radiocaine™. Serial PET/MR imaging will be performed over several hours post-injection to assess the distribution of the radiotracer in various tissues and organs. Blood and urine samples will be collected at predefined timepoints to support pharmacokinetic and dosimetry modeling. Safety assessments, including vital signs, laboratory tests, and monitoring for adverse events, will be conducted throughout the study.

The primary objectives are to:

• Evaluate the safety and tolerability of a single dose of Radiocaine™ in adults;
• Characterize the biodistribution of Radiocaine™ in key organs and tissues;
• Estimate radiation exposure (dosimetry) to inform future clinical use.

These data will guide dosing strategies, image acquisition timing, and safety parameters for future clinical studies. The results will also support the further development of Radiocaine™ as a potential diagnostic imaging agent and molecular imaging biomarker for the localization and quantification of sodium channel activity in human subjects.

This study is intended for early-stage characterization of Radiocaine™ in preparation for future clinical studies in disease-specific populations.

• Study Type: Interventional
• Enrollment (Estimated): 6
• Phase: Early Phase 1

Contacts and Locations

• Study Contact: Name: Chief Medical Officer; Phone Number: 877-310-1326; Email: info@lutrooimaging.com

Study Locations

• United States
  • California
    • Stanford, California, United States, 94305
      • Recruiting
      • Stanford University School of Medicine
      • Contact: Clinical Associate Professor of Radiology; Phone Number: (650) 724-4421; Email: srj8@stanford.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18 years and older
• Able to provide written consent
• Willing and able to undergo ECG, imaging, blood sampling, and complete self-assessment rating scales at the specified time points
• Unremarkable baseline health without report of chronic or acute pain
• Willing and able to participate in all imaging procedures and complete the self-assessment rating scales at the specified time points

Exclusion Criteria:

• Body mass index (BMI) of 32 or greater, weight >300 lbs
• Diagnosis of severe depression/anxiety (PROMIS score > 95%) or suicidal ideation
• History of opioid abuse or opioid use disorder
• History of seizures or epilepsy
• History of major Axis I or Axis II psychiatric disorder that might, in the opinion of the investigator, make it difficult for the subject to complete all the procedures (e.g. obsessive-compulsive disorder, bipolar disorder, schizophrenia, or schizoaffective disorder)
• History of cardiac arrhythmia
• History of major orthopedic surgery within the last 12 months
• Recent history (previous 6 months) of sodium channel blocker use, including, but not limited to: carbamazepine, lamotrigine, lidocaine, phenytoin, propranolol, or valproate
• Any significant systemic illness or medical condition that could lead to difficulty complying with the study protocol
• Creatinine clearance (calculated using the Cockcroft-Gault formula or measured) < 60 mL/min or serum creatinine >1.5 x ULN
• QTcF >470 msec for females and QTcF >450 msec for males on screening ECG
• MRI-incompatible implants, large tattoos, previous shrapnel injury
• Pregnancy or lactating
• History of contact sport participation, such as football, hockey, or rugby
• Known claustrophobia related to MR or PET-MRI scanners
• Recent blood donation/draw of >1 unit (previous 4 weeks)
• History of hypersensitivity to local anesthetics of the amide type
• Family or personal history of familial malignant hyperthermia

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Healthy subjects	Diagnostic test: Intravenous Radiocaine; Intravenous injection of Radiocaine

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Radiation absorbed dose/Effective dose		1 day
Adverse events	Presence/absence of adverse events	30 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Biodistribution	Biodistribution of Radiocaine	1 day

Collaborators and Investigators

• Sponsor: Lutroo Imaging LLC
• Collaborators: Stanford University

Study record dates

Study Major Dates

• Study Start (Actual): June 17, 2025
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): July 1, 2026

Study Registration Dates

• First Submitted: July 3, 2025
• First Submitted That Met QC Criteria: July 15, 2025
• First Posted (Actual): July 23, 2025

Study Record Updates

• Last Update Posted (Actual): May 11, 2026
• Last Update Submitted That Met QC Criteria: May 6, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: PET imaging; diagnostic imaging; medical imaging; Radiocaine
• Other Study ID Numbers: LTR-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No