Efficacy of Methylene Blue Photodynamic Therapy for Treatment of Deep Tissue Abscesses

Summary

The objective of this Phase 2 study is to evaluate the efficacy of methylene blue photodynamic therapy (MB-PDT) performed at the time of percutaneous abscess drainage for disinfection of deep tissue abscesses. The study includes three arms: (1) MB-PDT at a fixed drug/light dose plus standard of care abscess drainage , (2) MB-PDT at a patient-specific dose determined by pre-treatment optical measurements plus standard of care abscess drainage , and (3) standard of care abscess drainage. The primary endpoint is reduction in time to removal of the drainage catheter.

Conditions

• Abscess

Interventions

DRUG

Methylene Blue

Administration of 0.1 mg/mL methylene blue to the abscess cavity, followed by a 10 minute incubation interval. After this incubation interval, the methylene blue solution will be aspirated from the cavity and flushed twice with sterile saline.

DRUG

Lipid Emulsion

The abscess cavity will be filled with sterile 0.1% lipid emulsion solution to gently distend the cavity and, through efficient light scattering, to homogenize the light dose to the walls of the cavity. After laser illumination, the Intralipid will be aspirated from the cavity.

DEVICE

Insertion of optical fiber

A sterile, FDA-approved optical fiber will be advanced to the approximate center of the abscess cavity via the drainage catheter under image guidance. Following laser illumination, the fiber will be withdrawn.

DEVICE

Laser Illumination (pre-defined dose)

Laser illumination will be delivered via the optical fiber for a duration of 20 minutes. The optical power will be set such that the fluence rate at the abscess wall due to ballistic photons is 20 mW/cm2.

DEVICE

Optical Spectroscopy Measurement

The same sterile optical fiber used for treatment will be advanced through the drainage catheter/needle in order to make gentle contact with the wall of the cavity. Low-intensity, polarized white light will be delivered by a tungsten halogen lamp by the fiber, and captured by the same fiber. Light that has been de-polarized by interaction with tissue will be detected by a spectrometer and analyzed to extract tissue optical properties. Upon completion of these measurements, the fiber optic will be withdrawn, gently wiped with sterile gauze, and returned to the procedure cart.

DEVICE

Laser Illumination (patient-specific dose)

Laser illumination will be delivered via the optical fiber for a duration of 20 minutes. The optical power will be set to deliver a fluence rate of 20 mW/cm2 in 95% of the abscess wall, based upon abscess morphology and optical spectroscopy results.

PROCEDURE

Standard of care abscess drainage

Following standard practice, a drainage catheter will be placed in the abscess cavity and used to aspirate purulent fluid.

Sponsors & Collaborators

• University of Rochester

  lead OTHER

Principal Investigators

• Timothy M Baran, PhD · University of Rochester

• Ashwani K Sharma, MD · University of Rochester

• Laurie Christensen, BS · University of Rochester

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-07-15

Primary Completion

2031-06-30

Completion

2031-06-30

FDA Drug

Yes

Countries

• United States

Study Locations